diressta

Artikler i internasjonale fagfellevurderte journaler

Aynekulu, E., Denich, M., Tsegaye, D., Aerts, R., Neuwirth, B. and Boehmer, H.J. 2011. Dieback affects forest structure in a dry Afromontane forest in northern Ethiopia. Journal of Arid Environments doi:10.1016/j.jaridenv.2010.12.013.

Diress Tsegaye, Stein R. Moe, Paul Vedeld and Ermias Aynekulu. 2010. Land-use/cover dynamics in Northern Afar rangelands, Ethiopia. Agriculture Ecosystems & Environment 139 (1-2): 174-180.

DiressTsegaye, Mitiku Haile, and Stein R. Moe. 2010.The effect of land use on the recruitment and populatioon structure of the important food and fodder plant, Dobera glabra (Forssk.) Poir., in northern Afar. Journal of Arid Environments 74 (9): 1074-1082

Diress Tsegaye, Stein R. Moe, and Mitiku Haile. 2009. Livestock browsing, not water limitations, contributes to recruitment failure of Dobera glabra in Semiarid Ethiopia. Rangeland Ecology & Management 62 (6): 540-549.

Ermias Aynekulu, Manfred Denich, and Diress Tsegaye. 2009. Regeneration response of Juniperus procera and Olea europaea subsp cuspidata to Exclosure in a Dry Afromontane Forest in Northern Ethiopia. Mountain Research and Developmen29 (2): 143–152.

Diress Tsegaye, Nyariki, D.M. & Farah, K.O. 2000. Changing Land-use Systems and Socio-economic Roles of Vegetation in Semi-arid Africa: The case of the Afar and Tigrai of Ethiopia. J. Soc. Sci. 4:199-206.

Diress Tsegaye, Farah, K.O. & Nyariki, D.M. 1999. Influence of Settlements on Land Use and Vegetation in the Rangelands of Northeastern Ethiopia: Application of Aerial Photographic Technique. J. Hum. Ecol. 10: 349-356.

Submittede artikler

Diress Tsegaye, Stein R., Moe, Mitiku Haile. Seed predation and moisture limit germination of recalcitrant Dobera glabra (Salvadoraceae) seeds in the Afar rangelands, Ethiopia.

PhD oppgave

Diress Tsegaye. Afar pastoralists in a changing rangeland environment. 2010. PhD thesis, Department of Ecology and Natural Resources Management, Norwegian University of Life Sciences, Norway.

Masteroppgave

Diress Tsegaye, Kassim O. Farah, and Dickson M. Mbuvi. 1999. Impact of land use on vegetation resources with emphasis on woody vegetation in the semi-arid area of Aba'ala district, North Afar, Ethiopia. M.Sc. thesis, Department of Range management, University of Nairobi, Kenya.

Bøker

Aregay Waktola and Diress Tsegaye. 2005 (Under review for publication). Research methods: A textbook on concepts, principles and processes. Faculty of Dryland Agriculture and Natural Resources, Mekelle University.

Mitiku, H., Tsegaye, D. & Tegegene, T. (eds.). 2004. Research and development experiences of the Dryland Husbandry Project in Ethiopia. Dryland Husbandry Project, Mekelle University, Mekelle, Ethiopia. ISBN: 9781904855408. Pp. 174.

Ahmed, A.G.M., Alemayehu, A., Babiker, M. & Tsegaye, D. 2002. Post-drought recovery strategies among the pastoral households in the horn of Africa: A review. - Development Research Report Series no.3, Organization for Social Science Research in Eastern and Southern Africa (OSSREA) and Institute for Development Anthropology (IDA), Broadening Access and Strengthening Input Market Systems-Collaborative Research Support Program (BASIS-CRSP), USA. Addis Ababa. ISBN 1608-8875. Pp. 80.

Mitiku, H., Tegegne, T., Alemayehu, A., Tsegaye, D. & Merha, Z. (eds.). 1999. Proceedings of the National Workshop on "Challenges and Opportunities for Research and Development in Pastoral/agropastoral Areas of Ethiopia" 16-18 December 1998. - Dryland Husbandry Project, Mekelle University, Ethiopia.

• Alemu, Diress Tsegaye; Rizzi, Jonathan; Bayr, Ulrike; Debella-Gilo, Misganu; Adade, Richard & Aheto, Denis W. [Vis alle 7 forfattere av denne artikkelen] (2026). Mapping Potential Mangrove Forest Restoration Areas in Coastal Ghana Using Multi-Model Habitat Suitability Analysis. Land. 15(9). doi: 10.3390/land15091581. Fulltekst i vitenarkiv Vis sammendrag

  Extensive ecosystem degradation along the coastal areas of Ghana highlights the need for targeted landscape restoration. This study identified areas with high restoration potential by evaluating environmental, climatic, and anthropogenic determinants of mangrove distribution. We tested multiple habitat suitability models, including Random Forest (RF), Generalized Additive Model (GAM), Generalized Linear Model (GLM), Maximum Entropy (MaxEnt), and an ensemble approach. Mangrove occurrence records were compiled from field observations, drone-derived data, and publicly available biodiversity and mapped datasets. The ensemble GAM-RF model emerged as the most robust model, with the highest predictive performance. Hydrological and topographic factors were the strongest predictors of mangrove habitat suitability, particularly proximity to rivers and the coastline, low-elevation terrain (<5 m asl), and temperature-related bioclimatic variables, while precipitation metrics and anthropogenic proxies played secondary roles. Using the ensemble approach, the estimated potentially suitable habitat ranged from 417 to 1313 km2, indicating that substantial areas remain available for mangrove restoration. These findings align with ongoing national and international restoration initiatives, including the coastal restoration plan, and have important implications for coastal protection, carbon sequestration, fisheries habitat, and local livelihoods. Our findings demonstrate that multi-model habitat suitability analyses can guide spatially targeted, and evidence-based restoration planning.

• Alem, Habtamu; Alemu, Diress Tsegaye; Issifu, Ibrahim; Nortey, Daniel D.N.; Bana, Linda & Aheto, Denis W. [Vis alle 7 forfattere av denne artikkelen] (2026). Institutional capacity and divergent resilience pathways in coastal Ghana's mangrove social-ecological systems: Evidence from the Western Region and Lower Volta Delta. Ocean and Coastal Management. ISSN 0964-5691. 282. doi: 10.1016/j.ocecoaman.2026.108370. Fulltekst i vitenarkiv Vis sammendrag

  Mangrove condition reflects interactions among ecological pressures, livelihood dependence, institutional arrangements, and biophysical constraints on regeneration. This study compares seven purposively selected rapid-appraisal sites in Ghana's Greater Amanzule Wetlands in the Western Region and the Lower Volta Delta. Evidence combines May 2025 site appraisals, 14 semi-structured interviews, three group discussions, spatial and secondary ecological information, and historical livelihood context from GLSS7 (2016–2017). Institutional functioning was assessed descriptively through rule recognition and participation, monitoring and responses to violations, and collective action, without assigning unsupported site-level scores. Visible disturbance was lower in the Western sites, with a median score of 2 (range 2–3), than in the Lower Volta sites, where the median was 4. Stakeholder accounts also indicated more consistently recognised rules and participation in the Western system, while implementation was described as less consistent in the Lower Volta. Monitoring responsibilities, frequency, and responses to violations were insufficiently documented in both systems, preventing comparison of monitoring effectiveness. Because governance evidence was primarily regional and sites were purposively selected, these findings represent a descriptive association between two coastal systems, not seven independent institutional observations or a causal institutional effect. Hydrology, hydroperiod, sediment supply, salinity, geomorphology, and the scale of pressure also condition disturbance and regeneration opportunities. Effective responses should therefore combine participatory rule implementation, collective action, transparent monitoring arrangements, livelihood measures, and restoration strategies matched to local biophysical conditions and the geographical scale of dominant stressors.

• Chala, Desalegn; Alemu, Diress Tsegaye; Alem, Habtamu; Asalf, Belachew; Eshetu_Moges, Melesse & Abate, Nega Tassie [Vis alle 14 forfattere av denne artikkelen] (2026). Beyond Removal: Strategies for Sustainable Control of Water Hyacinth in Tropical Freshwater Ecosystems. Environmental Management. ISSN 0364-152X. 76(6). doi: 10.1007/s00267-026-02494-1. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Water hyacinth is among the world’s most damaging aquatic invasive plants, forming dense mats that disrupt ecosystem functioning, fisheries, navigation, and livelihoods across tropical and subtropical freshwater systems. Its rapid spread is driven by clonal propagation, short life cycles, and prolific seed production, particularly under nutrient-enriched conditions. Although mechanical, chemical, and biological control methods are widely applied, their long-term effectiveness remains uncertain when underlying eutrophication persists. Here, we present a large-scale, one-time water hyacinth removal campaign in Lake Tana, Ethiopia’s largest lake and a UNESCO Biosphere Reserve, as a representative nutrient-rich tropical freshwater system. Using high-resolution satellite imagery, we quantified coverage one month before removal, one month after removal, and one year later. We integrated SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis with a socio-ecological system map to assess mitigation mechanisms and identify sustainable management pathways capable of providing long-term solutions to halt water hyacinth proliferation in freshwater bodies. The campaign removed over 75% (~1271 ha) of water hyacinth, yet within one year the plant resurged to levels ~18% higher than pre-removal. This rebound highlights the ecological resilience of water hyacinth and the limitations of short term, noncontinuous control strategies. Our analysis identifies unmanaged catchment nutrient inputs as the primary driver of proliferation. Lake Tana serves as a model system demonstrating that water hyacinth functions less as a traditional invader and more as a bioindicator of eutrophication. We propose a transferable conceptual and methodological framework combining continuous removal, catchment-based nutrient management, and circular bioeconomy approaches, offering globally relevant lessons for sustainable management of nutrient-enriched tropical freshwater systems.

• Kapfer, Jutta; Pedersen, Christian; Alemu, Diress Tsegaye & Sickel, Hanne (2026). Short-Term Changes in High-Latitude Grassland Vegetation and Floral Reward Availability. Applied Vegetation Science. ISSN 1402-2001. 29(2). doi: 10.1111/avsc.70072. Fulltekst i vitenarkiv Vis sammendrag

  Aim Four different grassland types of varying land-use intensity and history were investigated for changes in plant species composition and richness over a 7- to 10-year period. Shifts in species occurrence frequencies and species-specific indicator values for nectar production were analyzed to assess how vegetation changes may influence the availability of floral rewards. Location Norwegian mainland. Methods We utilized survey (2004–2008) and resurvey (2011–2018) data from the Norwegian Monitoring Program for Agricultural Landscapes, examining vegetation in managed and unmanaged grasslands from 538 permanent vegetation plots within 97 monitoring squares across Norway. Using species-specific indicator values for nectar production, we tested how compositional changes in vascular plant communities are reflected in the occurrence frequency and cover of pollen- and nectar-providing plants. Results Grassland species composition has slightly shifted toward communities more dominated by later successional species, particularly those associated with shadier and wetter conditions. Major changes in the occurrence frequencies of individual species suggest a decline in pollen and nectar production. Specifically, 29 of 40 species (72.5%) that showed significant decreases in frequency were flowering plants important for pollinators. Across all grassland types, the average cover of pollen- and nectar-producing plants has declined over time, indicating a reduction in floral resources available to pollinating insects. Conclusions Our findings indicate a gradual transition in grassland habitats toward conditions that may be less favorable to pollinators, as reflected by changes in species occurrence frequencies and plant cover. Additionally, plant species associated with moist environments are likely to increase in abundance under continued climate change. This study highlights the value of systematic grassland monitoring within agricultural landscapes as an effective tool for detecting vegetation changes, even over short time spans. Such monitoring supports timely decision-making and the implementation of targeted management strategies to preserve ecologically and economically important habitat types.

• Berg, Sveinung Krokann; Alemu, Diress Tsegaye & Dramstad, Wenche (2025). Kulturarv i jordbrukslandskapet – kulturarvskategorier og forvaltningsnivå. Kart og Plan. ISSN 0047-3278. 118(3-4), s. 258–272. doi: 10.18261/kp.118.3-4.5. Fulltekst i vitenarkiv Vis sammendrag

  Å ivareta velferdsgoder er en sentral oppgave i helhetlig arealplanlegging og arealforvaltning. Jordbrukslandskapet leverer fellesgoder eller såkalte økosystemtjenester som bidrag til menneskelig velferd. I denne artikkelen ser vi på jordbrukets bidrag til kulturelle økosystemtjenester og hvordan kulturarvsverdier inngår i dette. Kulturelle økosystemtjenester bidrar til stedsidentitet, estetiske verdier og friluftsliv og betegnes gjerne som opplevelses- og kunnskapstjenester. At store deler av kulturarvsverdien ligger på jordbruksareal som antas å være ute av drift, tilsier en utvikling som kan få konsekvenser for forvaltningen av kulturarven. Vi foreslår derfor en nyansert forvaltning av kulturarv i jordbrukslandskapet, basert på tre kategorier kulturarv, og kobler disse til hvilket forvaltningsnivå som synes nødvendig for å ivareta kulturhistoriske elementer på ulike nivåer.

• Dramstad, Wenche; Alemu, Diress Tsegaye; Krøgli, Svein Olav; Pedersen, Christian & Aune-Lundberg, Linda (2025). Beyond provisioning: Unveiling ecosystem services of agricultural landscapes. Norsk Geografisk Tidsskrift. ISSN 0029-1951. 79(2), s. 101–107. doi: 10.1080/00291951.2025.2517600. Fulltekst i vitenarkiv Vis sammendrag

  The study focuses on ecosystem services, historical aspects, and natural diversity. Specifically, it assesses possible proxies for investigating a set of cultural ecosystem services from the Norwegian agricultural landscape. Agricultural areas on the Norwegian land cover map surrounded by a 100  m wide buffer zone were analyzed for recorded historical buildings, cultural heritage sites, red-listed vascular plant species (defined as being at varying degrees at risk of extinction), and red-listed nature types (defined as endangered or vulnerable). The results indicate significant contributions from agricultural landscapes with respect to historical buildings, cultural heritage sites, and red-listed plant species. Regarding red-listed nature types, the contributions were diverse. The ecosystem proxies investigated showed increasing distribution trends with increasing proportions of agricultural landscapes in the spatial units, with a sharp increase with smaller area sizes. However, for cultural heritage sites the trend was different when the proportion of the agricultural landscape was below 25%; it showed a very slow increase. In conclusion, the study highlights the agricultural landscape’s diverse contributions to the investigated ecosystem services in Norway, prompting the need for further research on additional ecosystem services to ensure the continued delivery of environmental and social well-being.

• Gebrekidan, Mebrat Teklemariam; Bekele, Afework; Alemu, Diress Tsegaye; Tilahun, Hailu; Beyene, Getacher & Bogale, Bezawork Afework (2025). Phytoplankton Community and Physico-chemical Parameters Influence on the Seasonal Visits of Lesser Flamingos (Phoeniconaias minor) in Chelekleka Wetland, Central Ethiopia. Tropical Conservation Science (TCS). 18. doi: 10.1177/19400829251314991. Fulltekst i vitenarkiv Vis sammendrag

  Background and Research Aims Lesser flamingo (Phoeniconaias minor) is an intra-African migratory bird species recorded mainly in alkaline lakes of the Great Rift Valley. Temporal patterns of Lesser flamingo visits may be related to the abundance and availability of their primary phytoplankton food items, and phytoplankton growth and composition may also be influenced by water quality parameters. This study aims to investigate the relationship between Lesser flamingo abundance and the physico-chemical characteristics of the wetland and its phytoplankton community dynamics. Methods We measured the abundance of Lesser flamingos using the ground vantage point counting method. We assessed water physico-chemical characteristics using field measurements of temperature, dissolved oxygen, pH, electrical conductivity and turbidity, and laboratory sample analyses for phosphorus, ammonia, nitrate, silica, alkalinity and chlorophyll a. We also measured phytoplankton diversity and abundance in the laboratory. Results The physico-chemical characteristics of the Chelekleka wetland showed a favorable environment for biological productivity and physiological activities of aquatic organisms. High phytoplankton richness (83 taxa) and abundance were recorded in the wetland. Lesser flamingo abundance varied significantly in response to the abundance of preferred phytoplankton prey items, which could be attributed to the effect of aquatic grazers and changes in the physico-chemical characteristics of the wetland. Conclusion Water physico-chemical characteristics influence the abundance and availability of phytoplankton in the seasonally flooded wetland, which in turn influences the seasonal visitation and abundance of Lesser flamingos foraging on phytoplankton prey. Implications for Conservation We recommend that the local government and other relevant stakeholders implement integrated wetland conservation practices to alleviate wetland degradation and conserve the ecosystem and its associated wildlife.

• Kufa, Chala Adugna; Bekele, Afework; Atickem, Anagaw Meshesha; Chala, Desalegn; Alemu, Diress Tsegaye & Ergon, Torbjørn [Vis alle 8 forfattere av denne artikkelen] (2025). Mapping suitable habitat and Anthropocene refugia for Ethiopian Guerezas: Insights for their conservation. Global Ecology and Conservation. 59. doi: 10.1016/j.gecco.2025.e03547. Fulltekst i vitenarkiv Vis sammendrag

  Ethiopia is home to two subspecies of Colobus guereza, C. g. guereza and C. g. gallarum. Whereas C. g. guereza is listed as Least Concern by IUCN, the conservation status of C. g. gallarum is unclear, but according to a recent assessment, it will most likely be listed as Vulnerable, because of habitat loss due to agricultural expansion. We used climate data to model the habitat suitability for both taxa in a comparative study to identify suitable habitats within and outside of protected areas that may serve as Anthropocene refugia. Our ensemble models estimated 168,731 km2 as climatically suitable habitat for C. g. guereza and 69,542 km2 for C. g. gallarum with an overlap between the two taxa of 17.2 %. Areas that qualified as refugia, i.e., areas covered by forest, were 47,101 km2 (only 27.9 % of the total suitable habitat) and 8430 km2 (12.1 % of the suitable habitat) for C. g. guereza and C. g. gallarum, respectively. Of these, 39.8 % (C. g. guereza) and 53.7 % (C. g. gallarum) are within Ethiopia’s current protected area network. Given that potential Anthropocene refugia are found only partly within protected areas, conservation management should include this information when developing conservation strategies for both taxa. As the majority of suitable habitats for the two colobus taxa exist in non-forested regions, afforestation in these areas would be highly beneficial and is strongly recommended.

• Disasa, Behailu Etana; Atickem, Anagaw Meshesha; Fashing, Peter; Alemu, Diress Tsegaye; Beenhouwer, Matthias De & Lens, Luc [Vis alle 8 forfattere av denne artikkelen] (2024). Mammalian community responses in relation to anthropogenic disturbances and resource gradients in the shade coffee forest ecosystem of Southwestern Ethiopia. Global Ecology and Conservation. 53. doi: 10.1016/j.gecco.2024.e02991. Fulltekst i vitenarkiv Vis sammendrag

  Understanding the effects of variation in resource availability and habitat disturbance on the ecology of mammals is vital for successful conservation management. In this study, we examined how human disturbances, resource availability and elevation gradients influence mammal assemblages in both managed coffee forest and natural forest of the Belete-Gera National Forest Priority Area, southwestern Ethiopia. We surveyed mammals using motion-detecting infrared camera traps in 90 locations for a total of 4142 camera days. We measured distance from main roads and settlements as disturbance factors, and distance from water sources, key grazing sites, and forest edges and woody plant diversity as resource variables. We assessed the mammal assemblages in coffee forest and natural forests using generalized linear models. Further, we used linear modelling to compare the relationships of mammal detection rates by feeding guilds and body size to resource variables. In total, we recorded 8815 videos identifying 23 different mammal species. The mammal assemblages in coffee forests were negatively associated with increasing distances from key grazing sites, water sources, and elevation. In contrast, the association with increasing distance from the road and woody plant diversity was positive. In addition, herbivores and large (25–200 kg) and very large (≥200 kg) mammals, were all negatively associated with increasing distance from the natural forest edges. With the conversion of natural forest to coffee forest and the intensification of coffee forest management, sustainable management of key grazing sites, water sources, and diverse woody plant species will be essential to the conservation of mammals. In addition, to ensure mammal conservation, adjacent natural forests around coffee forests should also be protected.

• Ahmed, Ahmed Seid; Atickem, Anagaw Meshesha; Bekele, Afework; Alemu, Diress Tsegaye; Stenseth, Nils Christian & Zinner, David J. [Vis alle 8 forfattere av denne artikkelen] (2024). New records of the Ethiopian long-eared bat Plecotus balensis in central Ethiopia. Journal of Wildlife and Biodiversity (JWB). 8(2), s. 179–192. doi: 10.5281/zenodo.11099537. Fulltekst i vitenarkiv Vis sammendrag

  The diversity of bats in Ethiopia comprises at least 80 species, among them the Ethiopian long-eared bat that was described in 2000. It is most likely endemic to the highlands of Ethiopia. However, knowledge of the distribution of the species is limited. During a bat survey in 12 regions of central Ethiopia stretched over 700 km along the Ethiopian Rift, we trapped long-eared bats at sites in three regions and confirmed the species' identity by molecular analysis. All occurrence sites of P. balensis were above 2500 m, confirming this taxon as a high-altitude species. Two of the regions are additions to the known range of P. balensis but it is most likely present in more high-altitude areas of Ethiopia than currently known. Additional surveys in so far unsampled areas are therefore indicated.

• Argaw, Hailu Tilahun; Bekele, Afework; Atickem, Anagaw Meshesha; Stenseth, Nils Christian; Alemu, Diress Tsegaye & Bogale, Bezawork Afework (2024). Habitat suitability and distribution patterns of Rouget's rail (Rougetius rougetii Guérin-méneville, 1843) in Ethiopia. Ecology and Evolution. 14(9), s. 1–10. doi: 10.1002/ece3.70276. Fulltekst i vitenarkiv Vis sammendrag

  Geographical distribution and diversity patterns of bird species are influenced by climate change. The Rouget's rail (Rougetius rougetii) is a ground-dwelling endemic bird species distributed in Ethiopia and Eritrea. It is a near-threatened species menaced by habitat loss, one of the main causes of population declines for bird species. The increasing effects of climate change may further threaten the species’ survival. So far, the spatial distribution of this species is not fully documented. With this study, we develop current potential suitable habitat and predict the future habitat shift of R. rougetii based on environmental data such as bioclimatic variables, population density, vegetation cover, and elevation using 10 algorithms. We evaluated the importance of environmental factors in shaping the bird's distribution and how it shifts under climate change scenarios. We used 182 records of R. rougetii from Ethiopia and nine bioclimatic, population density, vegetation cover, and elevation variables to run the 10 model algorithms. Among 10 algorithms, eight were selected for ensembling models according to their predictive abilities. The current suitable habitats for R. rougetii were predicted to cover an area of about 82,000 km2 despite being highly fragmented. The model suggested that temperature seasonality (bio4), elevation, and mean daily air temperatures of the driest quarter (bio9) contributed the most to delimiting suitable areas for this species. R. rougetii is sensitive to climate change associated with elevation, which leads shrinking distribution of suitable areas. The projected spatial and temporal pattern of habitat loss of R. rougetii suggests the importance of climate change mitigation and implementing long-term conservation and management strategies for this threatened endemic bird species.

• Alemu, Diress Tsegaye; Pedersen, Christian; Krøgli, Svein Olav; Bryn, Anders; Potthoff, Kerstin & Dramstad, Wenche (2024). Grazing and recreation: Spatial cooccurrences and conflicting aims in Norwegian mountain landscapes. CATENA. ISSN 0341-8162. 244, s. 1–10. doi: 10.1016/j.catena.2024.108271. Fulltekst i vitenarkiv Vis sammendrag

  Mountain areas in Norway provide important resources for livestock grazing. These resources are crucial for agricultural production in a country with limited agricultural land and a climate and topography that restrict production of feed and food. A key contributor in the harvest of these resources has been mountain summer farming and outfield grazing in general. However, the use of mountainous grazing resources has been declining strongly for several decades with the regrowth of formerly open areas as a consequence. In contrast, recreational use, number of holiday cabins and associated infrastructure is rapidly increasing. Conflicts between recreational and agriculture use have received increasing attention in different media. We investigated the spatial patterns of cabin development and key grazing areas in Norwegian mountain areas, analysing data on livestock, cabins, and associated infrastructure. We found a large number of cabins and associated infrastructure within high-quality grazing areas indicating that the quality of grazing has not been adequately considered in the location of new cabins. Taking into consideration that cabin development seems not to decrease, the reduced availability of grazing resources may result in an increasing level of conflict and also impact food security in the long run.

• Eftestøl, Sindre; Alemu, Diress Tsegaye; Flydal, Kjetil & Colman, Jonathan Edward (2023). Effects of Wind Power Development on Reindeer: Global Positioning System Monitoring and Herders’ Experience. Rangeland Ecology & Management. ISSN 1550-7424. 87, s. 55–68. doi: 10.1016/j.rama.2022.11.011. Fulltekst i vitenarkiv
• Størdal, Ingvild; Uleberg, Embla Vildalen; Alemu, Diress Tsegaye & Colman, Jonathan Edward (2023). Restoration of seagrass habitats: Effects of artificial and natural sediments on the development of transplanted eelgrass (Zostera marina). Aquatic Botany. ISSN 0304-3770. 188. doi: 10.1016/j.aquabot.2023.103677. Fulltekst i vitenarkiv Vis sammendrag

  Near-shore areas face multiple stressors, effects of climate change, coastal construction and contamination. Although capping the seabed in these areas with mineral masses can reduce the impact of legacy contaminants in sediment, it can also result in the loss of flora and sessile fauna, both of which are vital components of near-shore ecosystems. Eelgrass (Zostera marina) is essential to marine near-shore areas as it supports biodiversity and mitigates the effects of climate change. Therefore, it would be beneficial to modify the top layer of caps to facilitate the reestablishment of these ecosystems when capping near-shore areas. This study describes results from an in situ, six-month field experiment conducted to compare increase in leaf length over the growing season and survival of eelgrass transplanted in two commercially available substrates (Natural sand and Crushed stone) and indigenous sediment (i.e., indigenous control sediment) in a capping project in Horten Inner harbour, Norway. Similar leaf length increase was found in Natural sand and Indigenous control sediment, both significantly higher compared to Crushed stone substrate. Survival was highest in our case in the Indigenous control sediment (120 %), with no significant difference between Crushed stone (20 %) and Natural sand substrates (25 %). These findings emphasize the importance of selecting appropriate substrate for successful seagrass restoration.

• Gutema, Tariku Mekonnen; Mersha, Alemneh; Aticho, Abebayehu; Gemeda, Dessalegn Obsi; Diriba, Shiferaw & Alemu, Tibebu [Vis alle 11 forfattere av denne artikkelen] (2023). Wildlife roadkill in Southwestern Ethiopia: Hotspots, drivers, and victim species. Heliyon. 9(9). doi: 10.1016/j.heliyon.2023.e19783. Fulltekst i vitenarkiv Vis sammendrag

  Wildlife-vehicle collision (WVC) is one of the major causes of wildlife mortality and a concern for conservationists worldwide. The study of roadkill data that can be used to develop appropriate measures and strategies for both wildlife conservation and traffic safety to mitigate the WVC and animals' mortality. Extensive studies have been conducted in the developed countries on the identification of WVC hotspots and its potential impact; however, less attention is given in developing countries. Because of this, the problem is not well understood in developing countries. This study was intended to identify victim species, hotspot areas for roadkill, and factors that contribute to WVC in Jimma Zone, along three roads leading from Jimma City. Data were collected using a citizen science approach and a skilled man power road survey (March–September 2022) to document the number and type of species killed. Three road segments (135 km in total) were surveyed weekly as a baseline for future research. All statistical analyses were carried out using R-software. In the present study, a total of 84 roadkill specimens were collected from 16 different mammal species, of which 85.7% were medium-sized carnivores. The findings showed that Jackals (Canis mesomalis and Canis adustus) were the most frequently killed species (25%, n is 21), followed by Civettictis civetta (22.62%, n is 19). The study revealed that the major factors causing collisions include habitat type (forest cover) and wildlife behavior (nocturnal or diurnal). Further, the study revealed that the majority of WVC occurred at night (dusk) and at dawn in areas that are covered with dense forests. To minimize the potential risks of WVC and animals’ mortality, we suggest putting warning signs in hotspot areas where roadkill usually occur frequently. In addition, we recommend creating awareness among drivers, traffic police, and all communities about the negative impacts and consequences of collisions on the ecological and economic value of wildlife.

• Gutema, Tariku Mekonnen; Atickem, Anagaw; Tsegaye, Diress; Chala, Desalegn; Bekele, Afework & Sillero-Zubiri, Claudio [Vis alle 11 forfattere av denne artikkelen] (2022). Home range, habitat use, and activity patterns of African wolves (Canis lupaster) in the Ethiopian highlands. Global Ecology and Conservation. 40. doi: 10.1016/j.gecco.2022.e02324. Fulltekst i vitenarkiv Vis sammendrag

  African wolves (Canis lupaster) and Ethiopian wolves (C. simensis) occur often sympatrically across habitats in the Ethiopian Highlands, with recent studies finding evidence for interspecific competition. However, unlike the well-studied Ethiopian wolf, comparatively little is known about the ecology of the African wolf in the Ethiopian Highlands. To address this empirical gap, we collected data on home range size, habitat use, and activity patterns of radio-collared African wolves at the Guassa Menz Community Conservation Area (GCCA) and Borena Saynt Worehimenu National Park (BSNP). We followed the African wolves (5 in GCCA, 6 in BSNP) for 16 months and had 659 ± 83 encounters with each individual. The mean 95% kernel density estimate home range size of African wolves was higher in BSNP (4.5 ± 1.5 km2) than at GCCA (2.2 ± 0.7 km2). In 55% (n = 3934) of the encounters the wolves were found to be solitary, whereas in other encounters we found them in groups of two to seven. At both sites, the African wolves were more often found in areas close to human settlements than in more intact habitat, and they were mainly active at dawn and dusk. These results show flexibility in African wolf socioecology in response to habitat fragmentation and anthropogenic disturbance. We recommend further studies on major causes of spatial and temporal niche partitioning of Ethiopian wolves and African wolves in the Ethiopian Highlands.

• Aynekulu, Ermias; Sileshi, Gudeta W.; Rosenstock, Todd S.; Noordwijk, Meine van; Alemu, Diress Tsegaye & Koala, Jonas [Vis alle 10 forfattere av denne artikkelen] (2021). No changes in soil organic carbon and nitrogen following long-term prescribed burning and livestock exclusion in the Sudan-savanna woodlands of Burkina Faso. Basic and Applied Ecology. ISSN 1439-1791. 56, s. 165–175. doi: 10.1016/j.baae.2021.07.007. Fulltekst i vitenarkiv Vis sammendrag

  Fire and overgrazing reduce aboveground biomass, leading to land degradation and potential impacts on soil organic carbon (SOC) and total nitrogen (TN) dynamics. However, empirical data are lacking on how prescribed burning and livestock exclusion impact SOC in the long-term. Here we analyse the effects of 19 years of prescribed annual burning and livestock exclusion on tree density, SOC and TN concentrations in the Sudanian savanna ecoregion at two sites (Tiogo and Laba) in Burkina Faso. Results revealed that neither livestock exclusion nor prescribed burning had significant impact on SOC and TN concentrations. The results at both sites indicate that 19 years of livestock and fire exclusion did not result in a significant increase in tree density compared to grazing and annual prescribed burning. The overall mean (± SEM) of SOC stocks in the 0–50 cm depth increment in the unburnt (53.5 ± 4.7 Mg C ha−1) and annually burnt (56.4 ± 4.3 Mg C ha−1) plots at Tiogo were not statistically different. Similarly, at Laba there was no significant difference between the corresponding figures in the unburnt (37.9 ± 2.6 Mg ha−1) and in the annually burnt plots (38.6 ± 1.9 Mg ha−1). Increases in belowground inputs from root turnover may have countered changes in aboveground biomass, resulting in no net change in SOC and TN. We conclude that, contrary to our expectation and current policy recommendations, restricting burning or grazing did not result in increase in SOC stocks in this dry savanna ecosystem.

• Disasa, Behailu Etana; Atickem, Anagaw Meshesha; Tsegaye, Diress; Bekele, Afework; Beenhouwer, Matthias De & Hundera, Kitessa [Vis alle 9 forfattere av denne artikkelen] (2021). Traditional shade coffee forest systems act as refuges for medium- and large-sized mammals as natural forest dwindles in Ethiopia. Biological Conservation. ISSN 0006-3207. 260. doi: 10.1016/j.biocon.2021.109219. Fulltekst i vitenarkiv Vis sammendrag

  Ethiopian shade coffee plantations are well documented to be bird-friendly and act as refuges for disappearing tree species. The extent to which these plantations support mammal conservation, as well as mammal sensitivity to coffee intensification, remain little studied. We studied the distribution and diversity of mammals under three coffee management systems of differing intensities (i.e., semi-forest, semi-plantation, and plantation) and in nearby natural forests in Belete-Gera Forest Priority Area, southwestern Ethiopia. We detected mammals using 30 infrared camera traps at 90 stations for a total of 4142 camera days. We used the Shannon-Wiener diversity index for diversity analysis, generalized linear mixed model for comparison of independent detection, and non-metric multidimensional scaling to show the mammalian community composition. We recorded 8815 digital videos and a total of 23 mammal species. The overall species richness, diversity, and detection of mammals did not differ between the two traditional shade coffee management systems and the natural forest but was lower in the plantation coffee system. The mammal community composition also shows variation in resilience to coffee management intensity, with primates appearing to be generally more tolerant to management intensification. We ultimately show that traditionally managed Ethiopian shade coffee farms shelter diverse mammal communities, comparable to those in nearby natural forests. Therefore, supporting traditional coffee management practices and certifying them as mammal-friendly should be implemented as strategies for the conservation of mammals, as natural forests continue to decline in Ethiopia.

• Tamrat, Misganaw; Atickem, Anagaw Meshesha; Tsegaye, Diress; Fashing, Peter; Evangelista, Paul & Bekele, Afework [Vis alle 7 forfattere av denne artikkelen] (2021). Swayne's hartebeest (Alcelaphus buselaphus swaynei): Home range and activity patterns in Maze National Park, Ethiopia. Journal of Mammalogy. ISSN 0022-2372. 102(2), s. 396–403. doi: 10.1093/jmammal/gyaa185. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Home range and activity patterns of animals are important elements for wildlife management and conservation practices. We examined seasonal home range and daily activity patterns of the endangered Swayne’s hartebeest (Alcelaphus buselaphus swaynei) in Maze National Park, Ethiopia. We tracked two groups of Swayne’s hartebeests in open grassland for 1 year. Each group’s daily activities (0700–1900 h) and GPS locations were recorded at 15-min intervals on 5 days every month. Activities were grouped into five behavioral categories: feeding, resting, traveling, vigilance, and other. In addition, we carried out nocturnal monitoring during full moon periods to further document movements patterns. We produced 95% and 50% kernel density estimates (KDE) of home range sizes for each group. Home range estimates did not vary across seasons. Feeding and traveling peaked during the early morning and late afternoon, whereas resting occurred most frequently during the midday hours in both seasons. The proportion of time spent feeding was higher during the dry season, whereas a greater proportion of time was spent resting during the wet season. Vigilance behavior occurred consistently throughout the day during both seasons. Time spent feeding and traveling did not vary significantly between seasons. Activity patterns of Swayne’s hartebeests are strongly influenced both by time of day and season, while home range size is less influenced by seasonality and may instead reflect temporal variation in food availability. Our findings will help to inform management strategies and conserve one of the last two extant populations of Swayne’s hartebeests.

• Tröger, Carolin; Alemu, Diress Tsegaye & Hohmann, Ulf (2021). Roe deer population trend after reintroduction of Eurasian lynx within the Palatinate Forest: a first insight into a long-term study. European Journal of Ecology. 7(2), s. 71–87. doi: 10.17161/eurojecol.v7i2.15426. Fulltekst i vitenarkiv Vis sammendrag

  After becoming extinct approximately 250 years ago in the Palatinate Forest, the first Eurasian lynx (Lynx lynx) were reintroduced within this area in 2016, with 20 lynx reintroduced in the following five years. We observed the roe deer population within the Palatinate Forest before (2016) and during (2017–2019) the lynx reintroduction by estimating the population and evaluating the hunting bag. The roe deer population estimation based on the distance sampling method was conducted on ten defined transects with an average length of 48 km from 2016 to 2019, observing a 6,000 km transect length for 120 nights overall. An average of 6.54 ± 1.28 roe deer km-² was estimated over the course of the four years (2016 – 2019). Since we suspect that our estimations might underestimate the roe deer population within the Palatinate Forest, hence we preferred to use the roe deer count index for further analysis. Over the first four years (2016–2019), significant differences were neither found in the roe deer count index nor for the hunting bag in relation to the reintroduction of the lynx. The data and findings presented in this study provide a first insight into a long-term observation of a predator-prey system within the Palatinate Forest, with roe deer not having experienced a natural predator over a long time. In order to make coherent interpretations, long-term data is needed to estimate the population trends of both species within the Palatinate Forest.

• Eftestøl, Sindre; Tsegaye, Diress; Flydal, Kjetil & Colman, Jonathan Edward (2021). Cumulative effects of infrastructure and human disturbance: a case study with reindeer. Landscape Ecology. ISSN 0921-2973. 36, s. 2673–2689. doi: 10.1007/s10980-021-01263-1. Fulltekst i vitenarkiv Vis sammendrag

  Context Within Rangifer ranges, many studies focus on expanding infrastructure and human activity negatively influencing habitat use. Little documentation exists on how disturbances act in synergy (i.e. cumulative effects), nor methods to test such effects. Objectives (1) Investigate how cumulative disturbance at different distances affects reindeer habitat use and (2) at what disturbance levels and distances loss of habitat functionality occurs. Methods Disturbance intensity levels for trails and infrastructure were based on expected amount of human activity, on a scale from 1 to 6. To test cumulative disturbance, we adapted the multi-grain method and summed-up disturbance intensity levels within “disturbance distance intervals” (0–0.25, 0.25–1, 1–2 km, etc. instead of 0–0.25, 0–1, 0–2 km, etc.), and tested reindeers’ avoidance using GPS data for 2011–2018. Results We found decreased habitat use within 0.25 km with increasing cumulative disturbance for snow free and winter seasons. For spring, a similar effect occurred up to 1 km. Reductions in use in areas with highest cumulative disturbance within these zones were between 92 and 98%. Strongest avoidance during spring supports previous studies. Comparatively, the multi-grain approach showed negative effects up to 3 km. Conclusions Our approach provides novel results and precisely estimates where cumulative effects actually occur. Reindeer in our study tolerate low intensities of human disturbance, while further increase in disturbance intensity reduces habitat functionality. We suggest clustering future human developments within areas of high disturbance, i.e. where functional habitat use is already lost or highly reduced. Our method can be used for other areas and species.

• Tamrat, Misganaw; Atickem, Anagaw Meshesha; Tsegaye, Diress; Nguyen, Nga; Bekele, Afework & Evangelista, Paul [Vis alle 8 forfattere av denne artikkelen] (2020). Human-wildlife conflict and coexistence: A case study from Senkele Swayne's Hartebeest Sanctuary in Ethiopia. Wildlife Biology. ISSN 0909-6396. 2020(3). doi: 10.2981/wlb.00712. Fulltekst i vitenarkiv Vis sammendrag

  Human–wildlife conflict presents major challenges to both wildlife managers and rural livelihoods. Here, we investigated human–wildlife conflict in and around Senkele Swayne's Hartebeest Sanctuary (SSHS). We estimated the densities of wild animals within SSHS and conducted questionnaire interviews about livestock predation and crop raiding patterns with individuals in 378 households occurring <3000 m outside the Sanctuary's borders. Respondents reported that hyenas Crocuta crocuta and African wolves Canis anthus were the only livestock predators and were responsible for combined losses of ∼ 10% (29 207 USD) of their livestock over a three-year period. Hyenas predated cattle, goats, sheep, donkeys and horses, whereas African wolves targeted only goats and sheep. Hyena predation occurred both inside and outside SSHS, whereas African wolf predation occurred mainly near the inside periphery of the sanctuary. Most (58%) of the respondents experienced crop raiding of their farms by Swayne's hartebeest Alcelaphus buselaphus swaynei, warthogs Phacochoerus africanus and/or crested porcupines Hystrix cristata. Nearly two-thirds (64%) of the crop raiding occurred 1–1500 m from the sanctuary. Potatoes and maize were the most commonly raided crops. Local communities used guarding, patrolling, loud noises, smoky fires, flashes of light, fences and trenches as deterrence methods. Of the crop raiding species, only Swayne's hartebeests were regarded positively, while warthogs and crusted porcupines were viewed negatively by respondents. We conclude that although SSHS is of critical conservation value to the Swayne's hartebeest, the surrounding communities endure significant livestock predation and crop raiding by wild animals sheltered in the sanctuary. The survival of this relict population of Swayne's hartebeest in the sanctuary remains at risk unless the human–wildlife conflict in surrounding areas is resolved. This calls for site-specific measures in consultation with the local community.

• Reimers, Eigil; Eftestøl, Sindre; Alemu, Diress Tsegaye & Granum, Knut (2020). Reindeer fidelity to high quality winter pastures outcompete power line barrier effects. Rangifer. ISSN 0333-256X. 40(1), s. 27–40. doi: 10.7557/2.40.1.4968. Fulltekst i vitenarkiv Vis sammendrag

  We investigated barrier effects of a 66 kV power line established in 1966 before and after the line was upgraded to 132 kV in 2004 over a period of 44 years (1974-2017) in the North Ottadalen wild reindeer area (3245 km2 ) of which 1038 km2 are in use as winter pastures. The power line transects a peninsula (135 km2 ) with high quality winter pastures in the southeast periphery. The reindeer population originated from a nucleus herd of 402 animals of domestic origin released in the area in 1964-1965 and 100 resident wild animals. Yearly winter survey started in 1974 and reindeer were first surveyed south of the 66 kV power line in 1982. Comparing the number of animals recorded in the peninsula vs. the number of individuals expected relative to available grazing area during the three periods (1974-2004, 1982-2004 and 2005-2017), the number of animals recorded in the peninsula was 3.6–4.9 times higher than expected. Since the upgrade of the power line, a substantial part of the reindeer population grazed in the peninsula every year. We therefore conclude that there was no long-term barrier effect from the original power line and no barrier effects at all from the upgrade. However, during the first 5 surveys of this study, there were no animals in the peninsula. Therefore, even if there are several possible reasons for this, we cannot exclude the possibility of short-term barrier effects resulting from the construction of the original power line. Our results support recent studies that report no effects from existing power lines and contrast some previous findings that have reported strong longterm barrier and avoidance effects of such infrastructure for Rangifer migration and grazing behaviour.

• Tamrat, Misganaw; Atickem, Anagaw Meshesha; Tsegaye, Diress; Evangelista, Paul; Bekele, Afework & Stenseth, Nils Christian (2020). The effect of season and post-fire on habitat preferences of the endangered Swayne's hartebeest (Alcelaphus buselaphus swaynei) in Maze National Park, Ethiopia. BMC Ecology. 20. doi: 10.1186/s12898-020-0275-3. Fulltekst i vitenarkiv Vis sammendrag

  Background: The availability of preferred habitats determines the spatial and temporal distribution of herbivores in savanna ecosystems. Understanding habitat preference of a targeted wildlife species is crucial for developing efective conservation strategies. Habitat preference of large grazers in connection to grass height and post-fre efect has been debated for the last century. Here, we examined the efects of season, grass height and burning on the habitat preference on Swayne’s hartebeest (Alcelaphus buselaphus swaynei) in Maze National Park. Data for seasonal habitat selection were collected using both direct observation along established transect lines and pellet counting using permanently established plots. Every month, we measured grass height commonly preferred by Swayne’s hartebeest in grassland habitat. Starting from the frst week of burning, we recorded the abundance of Swayne’s hartebeest in both burned and unburned grassland patches. Results: From detected pellets, 94.3% were recorded in the grassland habitat indicating that other habitat types are less used despite their extensive cover>50% of the Park. During wet and early dry seasons, Swayne’s hartebeest exclusively preferred grassland habitat. We found that 85.2% (n=1079) and 85.3% (n=593) of individuals observed in areas with a grass height below 30 cm during wet and early-dry seasons, respectively; while 70.9% (n=2288) preferred grass height below 30 cm during the dry season. The density of Swayne’s hartebeest in burned grassland area was higher than unburned grassland areas up to 150 days since burning. However, in unburned grassland areas, the density was initially low but showed increasing trend for consecutive days, reaching similar density with burned areas after 150 days since burning. Conclusion: Swayne’s hartebeest exclusively preferred grassland habitat, particularly during wet and early-dry seasons, shortest available grass height in all seasons and were attracted to burned grassland areas. Our results suggested that fre played an important role in maintaining habitat quality in grassland, and that management should continue using controlled burning as a tool for the conservation of Swayne’s hartebeest. However, we remain cautious of our fndings given the paucity of information regarding other confounding factors and the absence of longterm data on fre disturbance.

• Gutema, Tariku Mekonnen; Atickem, Anagaw Meshesha; Alemu, Diress Tsegaye; Bekele, Afework; Sillero-Zubiri, Claudio & Marino, Jorgelina [Vis alle 10 forfattere av denne artikkelen] (2019). Foraging ecology of African wolves (Canis lupaster) and its implications for the conservation of Ethiopian wolves (Canis simensis). Royal Society Open Science. 6(9), s. 1–9. doi: 10.1098/rsos.190772. Fulltekst i vitenarkiv Vis sammendrag

  African wolves (AWs) are sympatric with endangered Ethiopian wolves (EWs) in parts of their range. Scat analyses have suggested a dietary overlap between AWs and EWs, raising the potential for exploitative competition, and a possible conservation threat to EWs. However, in contrast to that of the well-studied EW, the foraging ecology of AWs remains poorly characterized. Accordingly, we studied the foraging ecology of radio-collared AWs (n = 11 individuals) at two localities with varying levels of anthropogenic disturbance in the Ethiopian Highlands, the Guassa-Menz Community Conservation Area (GMCCA) and Borena-Saynt National Park (BSNP), accumulating 845 h of focal observation across 2952 feeding events. We also monitored rodent abundance and rodent trapping activity by local farmers who experience conflict with AWs. The AW diet consisted largely of rodents (22.0%), insects (24.8%), and goats and sheep (24.3%). Of the total rodents captured by farmers using local traps during peak barley production (July to November) in GMCCA, averaging 24.7 ± 8.5 rodents/hectare/day, 81% (N = 3009) were scavenged by AWs. Further, of all the rodents consumed by AWs, most (74%) were carcasses. These results reveal complex interactions between AWs and local farmers, and highlight the scavenging niche occupied by AWs in anthropogenically altered landscapes in contrast to the active hunting exhibited by EWs in more intact habitats. While AWs cause economic damage to local farmers through livestock predation, they appear to play an important role in scavenging pest rodents among farmlands, a pattern of behaviour which likely mitigates direct and indirect competition with EWs. We suggest two routes to promote the coexistence of AWs and EWs in the Ethiopian highlands: local education efforts highlighting the complex role AWs play in highland ecosystems to reduce their persecution, and enforced protection of intact habitats to preserve habitat preferred by EWs.

• Eftestøl, Sindre; Flydal, Kjetil; Tsegaye, Diress & Colman, Jonathan Edward (2019). Mining activity disturbs habitat use of reindeer in Finnmark, Northern Norway. Polar Biology. ISSN 0722-4060. 42(10), s. 1849–1858. doi: 10.1007/s00300-019-02563-8. Fulltekst i vitenarkiv
• Flydal, Kjetil; Tsegaye, Diress; Eftestøl, Sindre; Reimers, Eigil & Colman, Jonathan Edward (2019). Rangifer within areas of human influence: understanding effects in relation to spatiotemporal scales. Polar Biology. ISSN 0722-4060. 42(1), s. 1–16. doi: 10.1007/s00300-018-2410-6. Fulltekst i vitenarkiv
• Gebremichael, Gelaye; Alemu, Diress Tsegaye; Bunnefeld, Nils; Zinner, Dietmar & Atickem, Anagaw Meshesha (2019). Fluctuating asymmetry and feather growth bars as biomarkers to assess the habitat quality of shade coffee farming for avian diversity conservation. Royal Society Open Science. 6(8), s. 1–12. doi: 10.1098/rsos.190013. Fulltekst i vitenarkiv Vis sammendrag

  Shade coffee farming has been promoted as a means of combining sustainable coffee production and biodiversity conservation. Supporting this idea, similar levels of diversity and abundance of birds have been found in shade coffee and natural forests. However, diversity and abundance are not always good indicators of habitat quality because there may be a lag before population effects are observed following habitat conversion. Therefore, other indicators of habitat quality should be tested. In this paper, we investigate the use of two biomarkers: fluctuating asymmetry (FA) of tarsus length and rectrix mass, and feather growth bars (average growth bar width) to characterize the habitat quality of shade coffee and natural forests. We predicted higher FA and narrower feather growth bars in shade coffee forest versus natural forest, indicating higher quality in the latter. We measured and compared FA in tarsus length and rectrix mass and average growth bar width in more than 200 individuals of five bird species. The extent of FA in both tarsus length and rectrix mass was not different between the two forest types in any of the five species. Similarly, we found no difference in feather growth between shade coffee and natural forests for any species. Therefore, we conclude our comparison of biomarkers suggests that shade coffee farms and natural forests provide similar habitat quality for the five species we examined.

• Gutema, Tariku Mekonnen; Atickem, Anagaw Meshesha; Bekele, Afework; Sillero-Zubiri, Claudio; Kasso, Mohammed & Alemu, Diress Tsegaye [Vis alle 10 forfattere av denne artikkelen] (2018). Competition between sympatric wolf taxa: an example involving African and Ethiopian wolves. Royal Society Open Science. 5(5), s. 1–9. doi: 10.1098/rsos.172207. Fulltekst i vitenarkiv Vis sammendrag

  Carnivore populations are declining globally due to range contraction, persecution and prey depletion. One consequence of these patterns is increased range and niche overlap with other carnivores, and thus an elevated potential for competitive exclusion. Here, we document competition between an endangered canid, the Ethiopian wolf (EW), and the newly discovered African wolf (AW) in central Ethiopia. The diet of the ecological specialist EW was dominated by rodents, whereas the AW consumed a more diverse diet also including insects and non-rodent mammals. EWs used predominantly intact habitat, whereas AWs used mostly areas disturbed by humans and their livestock. We observed 82 encounters between the two species, of which 94% were agonistic. The outcomes of agonistic encounters followed a territory-specific dominance pattern, with EWs dominating in intact habitat and AWs in human-disturbed areas. For AWs, the likelihood of winning encounters also increased with group size. Rodent species consumed by EWs were also available in the human-disturbed areas, suggesting that these areas could be suitable habitat for EWs if AWs were not present. Increasing human encroachment not only affects the prey base of EWs, but also may impact their survival by intensifying competition with sympatric AWs.

• Skatter, Hans Gaute; Charlebois, ML; Eftestøl, Sindre; Tsegaye, Diress; Colman, Jonathan Edward & Kansas, JL [Vis alle 8 forfattere av denne artikkelen] (2017). Living in a burned landscape: woodland caribou (Rangifer tarandus caribou) use of postfire residual patches for calving in a high fire - low anthropogenic Boreal Shield ecozone. Canadian Journal of Zoology. ISSN 0008-4301. 95(12), s. 975–984. doi: 10.1139/cjz-2016-0307. Fulltekst i vitenarkiv
• Tsegaye, Diress; Colman, Jonathan Edward; Eftestøl, Sindre; Flydal, Kjetil; Røthe, Gunnlaug & Rapp, Kåre (2017). Reindeer spatial use before, during and after construction of a wind farm. Applied Animal Behaviour Science. ISSN 0168-1591. 195, s. 103–111. doi: 10.1016/j.applanim.2017.05.023. Fulltekst i vitenarkiv Vis sammendrag

  The Fakken Wind farm (WF) was built in 2010–12 on the Fakken peninsula on the south-east corner of the island of Vannøy. Field and GPS sampling was conducted to test the interaction between reindeer spatial use and the WF with associated infrastructure for the period 2007–2015. “Before data” for both direct observations and GPS-positions confirmed that the site where the WF was built was an important winter grazing area for reindeer. Testing data from before, during and after construction of the WF showed that the overall use on the island and for the WF area did not change during the study period. The reindeer density did not vary significantly among the periods, both for the WF and power line areas. We found no avoidance responses on reindeer spatial use towards the WF during the operation periods for direct observation data. However, we found some significant changes in reindeer area use that may be related to disturbance from human activities for the calving period during construction in WF zone 1 and road zone 1 (GPS-data), and for the power line area during construction in summer and autumn (direct observational data). Our study site represents an area where coexistence of reindeer husbandry and wind energy development is possible, with negligible effects on reindeer spatial use during and after WF development. We recommend that new WFs should be built close to existing infrastructure and limit an increase in human accessibility to remote areas where reindeer are less accustomed to human activity.

• Aynekulu, Ermias; Mekuria, Wolde; Alemu, Diress Tsegaye; Feyissa, Kenea; Angassa, Ayana & Leeuw, Jan de [Vis alle 7 forfattere av denne artikkelen] (2017). Long-term livestock exclosure did not affect soil carbon in southern Ethiopian rangelands. Geoderma. ISSN 0016-7061. 307, s. 1–7. doi: 10.1016/j.geoderma.2017.07.030. Fulltekst i vitenarkiv
• Colman, Jonathan Edward; Bergmo, Tine; Tsegaye, Diress; Flydal, Kjetil; Eftestøl, Sindre & Lilleeng, Marte Synnøve [Vis alle 7 forfattere av denne artikkelen] (2017). Wildlife response to infrastructure: the problem with confounding factors. Polar Biology. ISSN 0722-4060. 40, s. 477–482. doi: 10.1007/s00300-016-1960-8. Fulltekst i vitenarkiv
• Meaza, Hailemariam; Tsegaye, Diress & Nyssen, Jan (2016). Allocation of degraded hillsides to landless farmers and improved livelihoods in Tigray, Ethiopia. Norsk Geografisk Tidsskrift. ISSN 0029-1951. 70(1), s. 1–12. doi: 10.1080/00291951.2015.1091033. Fulltekst i vitenarkiv
• Eftestøl, Sindre; Alemu, Diress Tsegaye; Flydal, Kjetil & Colman, Jonathan Edward (2016). From high voltage (300 kV) to higher voltage (420 kV) power lines: reindeer avoid construction activities. Polar Biology. ISSN 0722-4060. 39(4), s. 689–699. doi: 10.1007/s00300-015-1825-6. Fulltekst i vitenarkiv
• Rannestad, Ole Tobias; Alemu, Diress Tsegaye; Munishi, Pantaleo K. T. & Moe, Stein Ragnar (2015). Bird Abundance, Diversity and Habitat Preferences in the Riparian Zone of a Disturbed Wetland Ecosystem – the Kilombero Valley, Tanzania. Wetlands (Wilmington, N.C.). ISSN 0277-5212. 35(3), s. 521–532. doi: 10.1007/s13157-015-0640-8. Fulltekst i vitenarkiv
• Colman, Jonathan Edward; Alemu, Diress Tsegaye; Flydal, Kjetil; Rivrud, Inger Maren; Reimers, Egill & Eftestøl, Sindre (2015). High-voltage power lines near wild reindeer calving areas. European Journal of Wildlife Research. ISSN 1612-4642. 61(6), s. 881–893. doi: 10.1007/s10344-015-0965-x. Fulltekst i vitenarkiv
• Reimers, Eigil; Tsegaye, Diress; Colman, Jonathan Edward & Eftestøl, Sindre (2014). Activity patterns in reindeer with domestic vs. wild ancestry. Applied Animal Behaviour Science. ISSN 0168-1591. 150, s. 74–84. doi: 10.1016/j.applanim.2013.10.010. Fulltekst i vitenarkiv
• Eftestøl, Sindre; Tsegaye, Diress; Herfindal, Ivar; Flydal, Kjetil & Colman, Jonathan Edward (2014). Measuring effects of linear obstacles on wildlife movements: accounting for the relationship between step length and crossing probability. European Journal of Wildlife Research. ISSN 1612-4642. 60(2), s. 271–278. doi: 10.1007/s10344-013-0779-7. Fulltekst i vitenarkiv
• Colman, Jonathan Edward; Eftestøl, Sindre; Alemu, Diress Tsegaye; Flydal, Kjetil & Mysterud, Atle (2013). Summer distribution of semi-domesticated reindeer relative to a new wind-power plant. European Journal of Wildlife Research. ISSN 1612-4642. 59(3), s. 359–370. doi: 10.1007/s10344-012-0682-7. Fulltekst i vitenarkiv
• Reimers, Eigil; Nieminen, Mauri & Tsegaye, Diress (2013). Antler casting in relation to parturition in semi-domesticated female reindeer. Rangifer. ISSN 0333-256X. 33(1), s. 17–24. doi: 10.7557/2.33.1.2722. Fulltekst i vitenarkiv
• Tsegaye, Diress; Vedeld, Pål & Moe, Stein Ragnar (2013). Pastoralists and livelihoods: A case study from northern Afar, Ethiopia. Journal of Arid Environments. ISSN 0140-1963. 91, s. 138–146. doi: 10.1016/j.jaridenv.2013.01.002. Fulltekst i vitenarkiv Vis sammendrag

  The changing contexts in the drylands of Africa in which pastoralists operate pose potential negative effects for the livelihood sustenance of pastoralists. We examined present livelihood adaptations among Afar pastoralists in north eastern Ethiopia through a household survey. With an average per capita income of 1.20 USD a day (PPP-adjusted in 2006), all households surveyed in the study area fall below the international 2 USD a day poverty line. Most Afar pastoralists have become increasingly involved in farming and non-farming/non-pastoral activities, but do not display a total detachment from traditional mobile herding. Pastoral households are still less likely to diversify their livelihoods, while semi-pastoral and agro-pastoral households keep livestock more as an additional insurance against failure in other livelihood activities such as farming. This indicates combining livestock production and farming has improved or at least constrained declines in livelihood outcomes. Our quantitative findings are congruent with the general patterns of pastoral livelihood contraction occurring in the region even if a substantial group of pastoralists continue to engage in keeping livestock. These findings are highly relevant in a management context, suggesting more encompassing, and locally adapted policy and development strategy rather than a wholesale abandonment of support to pastoral livelihood styles.

• Colman, Jonathan Edward; Alemu, Diress Tsegaye; Pedersen, Christian; Eidesen, Ruben; Arntsen, Herbjørg & Holand, Øystein [Vis alle 9 forfattere av denne artikkelen] (2012). Behavioral Interference Between Sympatric Reindeer and Domesticated Sheep in Norway. Rangeland Ecology & Management. ISSN 1550-7424. 65(3), s. 299–308. doi: 10.2111/REM-D-11-00094.1. Fulltekst i vitenarkiv Vis sammendrag

  Interspecific interaction among sympatric ungulates is important in management and conservation. We investigated behavioral interference between sympatric wild or semidomestic reindeer (Rangifer tarandus tarandus) and sheep (Ovis aries) in two field studies and one enclosure experiment. For free-ranging wild and semidomestic reindeer, interference between the two species increased with decreasing distances, occurring only at less than 200 m and 30 m, for wild and semidomestic reindeer, respectively, and neither species consistently dominated the other. In a controlled, duplicated experiment we tested interference and confrontations at the feeding patch level among semidomestic reindeer and sheep within 40 × 50 m enclosures. When new reindeer or sheep were introduced into enclosures already occupied by reindeer, new reindeer resulted in significantly more interference and confrontations among individuals compared to new sheep; i.e., intraspecific interference was more prevalent than interspecific interference at equal densities. For all study areas, confrontations decreased with time after “first encounter,” indicating cohabituation. A sympatric use of pastures was not visually disruptive for recorded grazing behavior for either species.

• Colman, Jonathan Edward; Lilleeng, Marte Synnøve; Tsegaye, Diress; Vigeland, Magnus Dehli & Reimers, Eigil (2012). Responses of wild reindeer (Rangifer tarandus tarandus) when provoked by a snow-kiter or skier: A model approach. Applied Animal Behaviour Science. ISSN 0168-1591. 142(1-2), s. 82–89. doi: 10.1016/j.applanim.2012.08.009. Fulltekst i vitenarkiv
• Abebe, Shiferaw; Lye, Kåre & Tsegaye, Diress (2012). Functional distances of woody species, proxy of ecological elasticity and provision for forest management. Journal of Horticulture and Forestry. 4, s. 136–147. doi: 10.5897/JHF12.002. Fulltekst i vitenarkiv
• Colman, Jonathan Edward; Eftestøl, Sindre; Tsegaye, Diress; Flydal, Kjetil & Mysterud, Atle (2012). Is a wind-power plant acting as a barrier for reindeer Rangifer tarandus tarandus movements? Wildlife Biology. ISSN 0909-6396. 18(4), s. 439–445. doi: 10.2981/11-116. Fulltekst i vitenarkiv
• Tsegaye, Diress; Moe, Stein Ragnar & Haile, M. (2011). Seed predation and moisture limit germination of recalcitrant Dobera glabra (Salvadoraceae) seeds in the Afar rangelands, Ethiopia. Journal of Arid Environments. ISSN 0140-1963. 75(10), s. 903–908. doi: 10.1016/j.jaridenv.2011.04.031. Fulltekst i vitenarkiv
• Aynekulu, Ermias; Denich, Manfred; Tsegaye, Diress; Aerts, Rien; Neuwirth, B. & Boehmer, H. J. (2011). Dieback affects forest structure in a dry Afromontane forest in northern Ethiopia. Journal of Arid Environments. ISSN 0140-1963. 75(5), s. 499–503. doi: 10.1016/j.jaridenv.2010.12.013. Fulltekst i vitenarkiv
• Tsegaye, Diress; Moe, Stein Ragnar; Vedeld, Paul & Aynekulu, Ermias (2010). Land-use/cover dynamics in Northern Afar rangelands, Ethiopia. Agriculture, Ecosystems & Environment. ISSN 0167-8809. 139(1-2), s. 174–180. doi: 10.1016/j.agee.2010.07.017. Fulltekst i vitenarkiv Vis sammendrag

  This study uses a combination of remote sensing data, field observations and information from local people to analyze the patterns and dynamics of land-use/cover changes for 35 years from 1972 to 2007 in the arid and semi-arid Northern Afar rangelands, Ethiopia. A pixel-based supervised image classification was used to map land-use/cover classes. People's perceptions and ecological time-lines were used to explain the driving forces linked to the changes. A rapid reduction in woodland cover (97%) and grassland cover (88%) took place between 1972 and 2007. Bushland cover increased more than threefold, while the size of cultivated land increased more than eightfold. Bare land increased moderately, whereas bushy grassland and scrubland remained stable. According to accounts from local people, major events that largely explain the changes include: (1) severe droughts in 1973/74 and 1984/85; (2) increase in dry years during the last decade; and (3) immigration and increased sedentarization of pastoralists. If the present land-use/cover change were to continue, coupled with a drier climate, people's livelihoods will be highly affected and the pastoral production system will be under increasing threat. (C) 2010 Elsevier B.V. All rights reserved.

• Tsegaye, Diress; Haile, Mitiku & Moe, Stein Ragnar (2010). The effect of land use on the recruitment and population structure of the important food and fodder plant, Dobera glabra (Forssk.) Poir., in northern Afar, Ethiopia. Journal of Arid Environments. ISSN 0140-1963. 74(9), s. 1074–1082. doi: 10.1016/j.jaridenv.2010.03.003. Fulltekst i vitenarkiv Vis sammendrag

  Dobera glabra (Forssk.) Poir, is a drought-tolerant evergreen woody species that is important for food security of pastoral Afar people in north-eastern Ethiopia. We examined population structure and abundance of D. glabra in the Afar rangelands, which have been subjected to considerable land-use changes. Factors determining the abundance of seedlings, shrubs and trees were analyzed using generalized linear models with land-use type, landform, aspect, elevation and soils as explanatory variables. The relative abundances of seedlings, shrubs and trees were 11%, 71% and 18%, respectively, which indicates poor recruitment. Land-use changes are a major reason for the low recruitment of seedlings, due to the clearance of land for cultivation, or increases in browsing pressure caused by pastoral sedentarization. Although the overall abundance of D. glabra was low, the 'little disturbed' areas had a relatively high abundance of shrubs compared to 'moderately disturbed', 'disturbed', and 'highly disturbed' areas. Some soil parameters were related to abundance, but there was no clear evidence that environmental variables contributed to the decline of D. glabra. In order to preserve this important species, we propose management strategies that focus on protection of certain areas in combination with planting in the home gardens of settled Afar pastoralists. (C) 2010 Elsevier Ltd. All rights reserved.

• Tsegaye, Diress; Moe, Stein Ragnar & Haile, Mitiku (2009). Livestock browsing, not water limitations, contributes to recruitment failure of Dobera glabra in semiarid Ethiopia. Rangeland Ecology & Management. ISSN 1550-7424. 62(6), s. 540–549. doi: 10.2111/08-219.1. Fulltekst i vitenarkiv Vis sammendrag

  The study used nursery and field experiments to investigate why recruitment of Dobera glabra (Forssk) Poir., a native food source for both humans and livestock, often fails in the semiarid rangelands of Afar, Ethiopia. We hypothesized that soil water limitations and browsing by livestock would be the primary mechanisms accounting for the failure of natural regeneration. We used three sets of experiments-1) seedling performance in response to shade and watering in a nursery, 2) field regeneration with and without browsing, and 3) regeneration beneath trees with and without browsing-to examine regeneration success. Seedlings were established in plots from seeds sown directly into the soil for nursery and field experiments, but natural germination occurred beneath trees. Survival and relative growth rates (RGR) were used to monitor seedling performance. Seedlings that received neither shade nor watering treatments had lower seedling survival (53 +/- 15%) as compared with other treatment combinations. Highest seedling survival was recorded under shade and 1 d watering . wk(-1) treatment combinations (92 +/- 1%). However, shade treatments had a minimal increase on seedling RGR. Water limitation is not a crucial limiting factor for D. glabra recruitment, as 53% of the seedlings survived without both shade and supplemental water for 1 yr. Field experiments, however, demonstrated that browsing greatly reduced seedling survival (below 15%) and suppressed growth of surviving seedlings, suggesting that browsing is the major factor preventing natural recruitment. Natural recruitment of D. glabra is unlikely with the existing continuous and intensive grazing/browsing in Afar rangelands, where the mobility of pastoralists is restricted. We suggest that planting nursery-raised seedlings in home gardens of settled pastoralists and establishment of grazing reserves in some key range sites that contain D. glabra could help offset the recruitment failure of native food species D. glabra in Afar rangelands.

• Aynekulu, Ermias; Denich, Manfred & Alemu, Diress (2009). Regeneration response of Juniperus procera and Olea europaea subsp cuspidata to exclosure in a dry Afromontane forest in northern Ethiopia. Mountain Research and Development Journal. ISSN 0276-4741. 29(2), s. 143–152. doi: 10.1659/mrd.1076. Fulltekst i vitenarkiv Vis sammendrag

  The Afromontane forests of northern Ethiopia have been degraded and fragmented for centuries. Recently, efforts have been made to restore these forests by protecting them from livestock interference. In this study, the natural regeneration of Juniperus procera Hochst. ex Endl. and Olea europaea L. subsp cuspidata (Wall. ex G. Don) Cif. is investigated under protected conditions after 3 years of enclosure and under open management systems in a dry Afromontane forest in northern Ethiopia. Data on the floristic and structural compositions of the vascular plants were collected using 32 randomly selected plots (20 m 3 20 m), while nested plots (10 m 3 10 m) were used to investigate the seedling bank at the protected and adjacent open sites. The results reveal that there was a significantly higher regeneration of O. europaea on the protected site than on the open site (P = 0.01). However, there was no significant difference between the 2 sites for J. procera (P = 0.16). Thus, protecting the degraded forest in northern Ethiopia seems to be an appropriate management option for the regeneration of O. europaea. The regeneration status of J. procera at both sites is poor, which indicates that protecting the forest from livestock and human disturbance is unlikely to lead to regeneration of this species. Further investigation of other factors that hinder the regeneration of J. procera is therefore recommended.

• Alemu, Diress Tsegaye; Nyariki, Dickson M. & Farah, Kassim O. (2000). Changing Land-use Systems and Socio-economic Roles of Vegetation in Semi-arid Africa: The case of the Afar and Tigrai of Ethiopia. Journal of Social Sciences. ISSN 0971-8923. 4, s. 199–206. Fulltekst i vitenarkiv
• Alemu, Diress Tsegaye; Farah, Kassim O. & Nyariki, Dickson M. (1999). Influence of Settlements on Land Use and Vegetation in the Rangelands of Northeastern Ethiopia: Application of Aerial Photographic Technique. Journal of Human Ecology. ISSN 0970-9274. 10, s. 349–356. Fulltekst i vitenarkiv

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• Pedersen, Christian & Alemu, Diress Tsegaye (2026). Fuglenes bestandsutvikling i det norske jordbrukslandskapet 2000–2023. NIBIO POP. ISSN 2464-1170. 12(1). Fulltekst i vitenarkiv Vis sammendrag

  Fuglebestandene i det norske jordbrukslandskapet går tilbake. Nye tall fra 3Q-programmet viser en nedgang på rundt 25 prosent siden 2000. Utviklingen tyder på at endringer i arealbruk og driftsformer påvirker leveområdene til mange arter, og viser behovet for målrettede tiltak for et mer variert jordbrukslandskap.

• Stokstad, Grete & Alemu, Diress Tsegaye (2025). Arealer ute av drift: Utvikling i ulike deler av landet og over tid. Fulltekst i vitenarkiv
• Pedersen, Christian & Alemu, Diress Tsegaye (2025). NIBIOs ferske farmland bird index (FBI). Fulltekst i vitenarkiv
• Pedersen, Christian; Krøgli, Svein Olav; Karan, Shivesh; Dale, Svein; Stokstad, Grete & Alemu, Diress Tsegaye (2025). Impact of Land Use Diversity and Agricultural Practices on Farmland Bird Populations: Insights from Norway's Monitoring Programme. Fulltekst i vitenarkiv Vis sammendrag

  Over recent decades, farmland and meadow-breeding bird populations in Europe have markedly declined, attributed to factors like agricultural intensification and land abandonment. Parts of the Norwegian Monitoring Programme for Agricultural Landscapes explore the correlation between land use and bird species, aiming to understand how spatial heterogeneity and land use diversity affect the richness, abundance, and distribution of farmland birds. Between 2000 and 2023, we saw declining populations and reduced distributions of several farmland bird species within the monitoring squares. Additionally, we found that both spatial heterogeneity of land use and high land type diversity positively influenced farmland birds. This gives important insight on how to design biodiverse agricultural landscapes. We also examined the impact of agricultural intensity on 25 farmland bird species, using livestock density and pasture size as indicators. Larger pastures generally benefited a wide range of farmland bird species. Different bird species responded variably to livestock numbers, but high livestock density led to a decrease in overall farmland bird abundance. Many countries subsidize sustainable farming to protect biodiversity. We studied Norwegian agri-environmental schemes' impact on farmland and meadow-breeding birds. We found that bird observations rose when these measures were in place but often declined once the support ended. Furthermore, the schemes were geographically limited and relatively few farmers participated. While short-term benefits were evident, long-term effects remain uncertain, highlighting the need for improved conservation strategies. Emphasizing the importance of spatially heterogeneous agricultural landscapes with high land type diversity and natural areas, the study indicates the type of agricultural landscapes we should be aiming for to maintain and restore biodiversity.

• Dramstad, Wenche; Fjellstad, Wendy Jane & Alemu, Diress Tsegaye (2025). Indicators to monitor the success of agri-environmental policies for pollinators. Fulltekst i vitenarkiv
• Ødmann, Andrea; Alemu, Diress Tsegaye; Utsi, Tove Aagnes & Wagner, Gabriela (2025). A new reindeer herd and a new windfarm: a coincidence for adaptation through increased herding activity or crisis? doi: https:/nibio.pameldingssystem.no/reindriftskonferansen-2025. Fulltekst i vitenarkiv
• Alemu, Diress Tsegaye & Dramstad, Wenche (2025). Mange arter er fortsatt tilstede. NIBIO POP. ISSN 2464-1170. 11(14). Fulltekst i vitenarkiv Vis sammendrag

  Effektivisering og intensivering av jordbruket har vært nødvendig for å nå målet om økt matproduksjon, fø en voksende befolkning og avverge sult, men fikk samtidig negative effekter for naturmangfoldet. Mange av artene som i dag finnes på rødlista er imidlertid fortsatt til stede i landskapet. Det innebærer et potensial for en positiv utvikling for disse artene, om forholdene legges til rette for det.

• Ødmann, Andrea; Alemu, Diress Tsegaye; Utsi, Tove Aagnes & Wagner, Gabriela (2025). A new reindeer herd and a new windfarm: a coincidence for adaptation through increased herding activity or crisis? Rangifer. ISSN 0333-256X. s. 54–54. Fulltekst i vitenarkiv
• Dramstad, Wenche & Alemu, Diress Tsegaye (2024). Noe spennende her? Fulltekst i vitenarkiv
• Alemu, Diress Tsegaye; Krøgli, Svein Olav & Dramstad, Wenche (2024). Red-listed plants persisting in the agricultural landscape. Fulltekst i vitenarkiv
• Dramstad, Wenche & Alemu, Diress Tsegaye (2024). Insektenes landskap - hva betyr noe? Fulltekst i vitenarkiv
• Bryn, Anders; Alemu, Diress Tsegaye; Pedersen, Christian; Krøgli, Svein Olav; Potthoff, Kerstin & Dramstad, Wenche (2024). Beitebruk og fritidsboliger: arealbruk i endring. Fulltekst i vitenarkiv
• Dramstad, Wenche; Alemu, Diress Tsegaye; Aune-Lundberg, Linda; Krøgli, Svein Olav & Pedersen, Christian (2023). Naturmangfold og kulturarv i jordbrukslandskapet. Fulltekst i vitenarkiv
• Reimers, Eigil; Flydal, Kjetil; Korslund, Lars; Eftestøl, Sindre; Colman, Jonathan Edward & Alemu, Diress Tsegaye (2015). Power lines, reindeer and UV. Biological Conservation. ISSN 0006-3207. 184, s. 471–471. doi: 10.1016/j.biocon.2014.12.026. Fulltekst i vitenarkiv
• Ali, Shaukat; Yue, Tao; Tse, T. & Wong, Eric (2014). Assessing the Modeling of Aspect State Machines for Testing From the Perspective of Modelers. Fulltekst i vitenarkiv Vis sammendrag

  Aspect state machines (ASMs) are extended UML state machines that use stereotypes from a UML profile called AspectSM. ASMs were specifically developed to support model-based robustness testing at Cisco Systems Norway, Inc. In our previous experiments, we empirically evaluated ASMs from the perspectives of readability, comprehensibility, understandability, modeling errors, and modeling effort and the results showed that ASMs are significantly better than the standard UML state machines for modeling robustness behavior for testing. However, a fundamental question still remained to be answered about how modelers/testers modeling ASMs feel about their use. With this in mind, we report results from a series of controlled experiments that were conducted to evaluate subjective opinions of modelers/testers from various perspectives using several questionnaires. The results of the experiment showed that the participants found it difficult to apply AspectSM and weren't confident about their solutions. We further observed that the participants' understandability and experience of applying AspectSM improved after performing various modeling activities. Although, our results seem very generic, but notice that these results provide preliminary evidence about these observations, which is missing in the Aspect-Oriented Modeling literature.

• Rubab, Iram; Ali, Shaukat; Briand, Lionel & Tse, T. (2014). Model-Based Testing of Obligations. Fulltekst i vitenarkiv Vis sammendrag

  Obligations are mandatory actions that users must perform, addressing access control requirements. To ensure that such obligations are implemented correctly, an automated and systematic testing approach is often recommended. One such approach is Model-Based Testing (MBT) that allows defining cost-effective testing strategies to support rigorous testing via automation. In this paper, we present MBT for obligations by extending the Unified Modeling Language (UML) via a profile called the Obligations Profile. Based on the profile, we define a modeling methodology based on the concepts of Obligations Class Diagrams (OCDs) and Obligations State Machines (OSMs), which are standard UML Class Diagrams and UML State Machines with stereotypes from the Obligations Profile. Our methodology, using OCDs and OSMs, is automatically enforced by the validation of constraints defined in the profile. To assess the completeness and applicability of the profile and methodology, we modeled 47 obligations from four different systems. The results of our experiment show that we successfully modeled all the obligations and used 75% of the stereotypes that we defined in the profile. In addition, using OCDs and OSMs, we automatically generate executable test cases using a standard state machine structural coverage criterion and common test data generation strategies. The effectiveness of generated test cases is assessed using mutation analysis on two systems, using mutation operators specifically designed for obligation faults. Test case executions killed 75% of the mutants and a careful analysis further suggests that more sophisticated testing strategies must be defined to further improve testing effectiveness.

• Yue, Tao; Ali, Shaukat; Tse, T. & Wong, Eric (2014). Exploring Model-Based Repositories for a Broad Range of Industrial Applications and Challenges. Fulltekst i vitenarkiv Vis sammendrag

  Nowadays, systems are becoming increasingly complex and large and the process of developing such large-scale systems is becoming complicated with high cost and enormous effort required. Such a complicated process has a prominent challenge to ensure the quality of delivered artifacts. Therefore there is clearly a need to facilitate reuse of developed artifacts (e.g., requirements, architecture, tests) and enable automated analyses such as risk analyses, prioritizing test cases, change impact analysis, with the objective to reduce cost, effort and improve quality. Model-based engineering provides a promising mechanism to facilitate reuse and enable automation. The key idea is to use models as the backbone of structuring repositories that contain reusable artifacts (e.g., test cases, requirements). Such a backbone model is subsequently used to enable various types of automation such as model-based testing and automated rule verification. In this paper, we report 12 industrial projects from five differ-ent industry domains that all require the construction of model-based reposito-ries to enable various types of automation. We believe using models as the backbone to structure repositories for the purpose of enabling different types of automation in different contexts is a new and non-conventional model-based development research approach. This exploratory paper will serve the basis for future research to derive a generic model-based repository.

• Colman, Jonathan Edward; Tröger, Carolin; Eftestøl, Sindre & Tsegaye, Diress (2012). The Strip Transect Method (STM) versus the Plot Sampling Method (PSM); what provides the best data in the least amount of time? Fulltekst i vitenarkiv
• Eftestøl, Sindre; Colman, Jonathan Edward; Tsegaye, Diress & Flydal, Kjetil (2012). Are consecutive GPS positions the best method for testing reindeers’ speed of movement when crossing linear structures? Fulltekst i vitenarkiv
• Colman, Jonathan Edward; Eftestøl, Sindre; Bergmo, Tine; Moe, Stein Ragnar; Flydal, Kjetil & Tsegaye, Diress (2012). Avoidance and barrier effects of a 420 kV power line on range use and migration patterns of semi-domestic reindeer. Fulltekst i vitenarkiv
• Colman, Jonathan Edward; Lin, Wenjiao; Moe, Stein Ragnar & Tsegaye, Diress (2012). The influence of reindeer grazing and trampling on newly seeded fields in northern Norway. Fulltekst i vitenarkiv
• Jaastad, Gunnhild; Hatteland, Bjørn Arild; Trandem, Nina; Dramstad, Wenche; Alemu, Diress Tsegaye & Sigsgaard, Lene (2026). Landskapsblikk på plantevern i frukt - Rapport frå forprosjektet Landskapsperspektiv på plantevern for berekraftig utvikling i norsk fruktproduksjon. NIBIO. ISSN 9788217039983. Fulltekst i vitenarkiv Vis sammendrag

  Endringar i driftsform, teigstruktur og landskap i fruktproduksjonen har skapt behov for betre kunnskap om korleis insekt responderer på ulike landskapstypar. I dette forprosjektet (2022-2023) undersøkte me korleis landskapet rundt fruktfelt kan påverka førekomst av skadeinsekt, nyttedyr og omfanget av fruktskadar. Fire fruktbruk i Sørfjorden vart studerte. To ligg i fragmenterte landskap med mange arealbrukstypar, og to i meir samanhengande fruktområde. Landskapet vart kartlagt ved hjelp av AR5 (arealressurskart i målestokk 1:5000 buffersoner) og registrering av overgangar mellom arealbrukstypar. Insekt vart samla inn med bankehåv og feromonfeller, og skadar på frukt vart registrert rett før hausting. Analysane viste store skilnader mellom felt innanfor 50 m radius rundt midtpunktet i felta, medan dei likna meir kvarandre når ein såg på arealbruk innanfor 500 m radius. Dette støttar at val av skala er avgjerande i studiar av landskapseffektar. Fangsten av skadeinsekt var låg, og det vart ikkje funne klare koplingar mellom landskap og skadeomfang. Nebbteger var det viktigaste nyttedyret, med varierande førekomst mellom felt, men utan eintydig samanheng med graden av fragmentering. Skadar på frukt var generelt låge. Prosjektet konkluderer med at metodar som kombinerer buffersoner, arealbrukstypar, kantregistrering og diversitetsanalysar er eigna for å vurdere landskapet frå eit insektperspektiv. Eit forprosjekt kan ikkje ta høgde for kompleksiteten i interaksjonar mellom bruk og storleik av areal, planter og skade- og nytteinsekt, men det kan fanga opp trendar, vurdera metodar og leggja grunnlag for relevante forskingsspørsmål. Det har vore ambisjonsnivået i dette prosjektet. For å avgjere om landskapet bør påverke val av plantevernstrategi, trengst det fleire undersøkingar i fleire felt over fleire år og meir detaljert informasjon om drift og vegetasjon. Dette ynskjer me å undersøkja i eit hovudprosjekt.

• Mathiesen, Henrik Forsberg; Krøgli, Svein Olav; Aune-Lundberg, Linda; Fadnes, Kjetil Damsberg; Tenge, Ingrid Midtsundstad & Pedersen, Christian [Vis alle 8 forfattere av denne artikkelen] (2025). Jordbruksareal ute av drift. Kunnskapsgrunnlag. NIBIO. ISSN 9788217038993. Fulltekst i vitenarkiv Vis sammendrag

  NIBIO lager årlig en oversikt over maskinelt høstbart og totalt jordbruksareal som kan være ute av drift. I denne rapporten sammenfatter vi data og analyser for perioden 2018 til og med 2024. This report compares mapped agricultural land with the agricultural area listed in applications for agricultural production subsidies between 2018-2024. The study shows that 13 percent of Norway’s agricultural land was apparently not being used for agriculture. The report discusses trends and reasons behind an apparent high level of farmland abandonment.

• Lebesbye, Einar Lyche; Colman, Jonathan Edward; Helle, Anders Gunnar & Alemu, Diress Tsegaye (2024). Assessing the ecological effects of the Lista wind power park on vegetation and cervids. Norges miljø- og biovitenskapelige universitet (NMBU). Fulltekst i vitenarkiv Vis sammendrag

  Land-based wind power is considered one of the most applicable sources of renewable energy for the future. While cost effective, the knowledge of ecological consequences associated with construction and operation is limited. This thesis investigates how vegetation and cervid animals at Lista Wind Park were affected by its construction and operation. Vegetation data in revegetated and control plots were compared over a twelve-year period and tested for variation in species richness, species diversity and foliar coverage. Dispersal of alien species, as a result of infrastructure construction, was also investigated. Cervid habitat use was mapped one year before, during construction and several different years after the wind park was set into operation. This data was considered unreliable due to inconsistency in sampling circumstances and lack of calibration between observers, and not analysed further. Rather, inter-observer discrepancies in species identification were investigated. Vegetation in revegetated plots seems to converge towards control plots after twelve years. Differences in species richness, species diversity and foliar cover are no longer significant. However, models fail to account possible variations due to climate. The construction of the wind park resulted in dispersal of alien species. In general, experienced observers had trouble identifying species though photographs of feces, only being certain in ca. 50% of the cases. In cases where observers were certain, species ID was different compared to another observer in 19% of the cases. More studies are needed to determine land-based wind powers ecological consequences, especially on cervids.

• Colman, Jonathan Edward; Eftestøl, Sindre; Flydal, Kjetil; Rapp, Kåre; Røthe, Gunnlaug & Tsegaye, Diress (2012). VindRein-KraftRein - Essand – Vannøy – Fosen – Setesdal aust- og vesthei – Kjøllefjord – Berlevåg og Sørøya. Årsrapport 2011. Biologisk inst.. Fulltekst i vitenarkiv
• Kebebew, F.; Tsegaye, Diress & Synnevåg, Gry (2001). Traditional coping strategies of the Afar and Borana pastoralists in response to drought. Dryland Coordination Group. Fulltekst i vitenarkiv

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