| 1. |
- Allen, Andrew, et al.
(författare)
-
Habitat-performance relationships of a large mammal on a predator-free island dominated by humans
- 2017
-
Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 7, s. 305-319
-
Tidskriftsartikel (refereegranskat)abstract
- The demographic consequences of changes in habitat use driven by human modification of landscape, and/or changes in climate, are important for any species. We investigated habitat-performance relationships in a declining island population of a large mammal, the moose (Alces alces), in an environment that is predator-free but dominated by humans. We used a combination of demographic data, knowledge of habitat selection, and multiannual movement data of female moose (n = 17) to understand how space use patterns affect fecundity and calf survival. The calving rate was 0.64 and was similar to calving rates reported in other populations. Calf survival was 0.22 (annually) and 0.32 (postsummer), which are particularly low compared to other populations where postsummer survival is typically above 0.7. Home ranges were mainly composed of arable land (>40%), and selection for arable land was higher in winter than in summer, which contrasts with previous studies. Females that spent more time in broadleaf forest in the summer prior to the rut had higher fecundity rates, while more time spent in arable land resulted in lower fecundity rates. Females that spent more time in thicket/scrubland habitats during winter had lower calf survival, while females that had higher use of mixed forests tended to have higher calf survival. The dominance, and subsequent use, of suboptimal foraging habitats may lead to poor body condition of females at parturition, which may lower calf body weights and affect the mother's ability to lactate. In addition, our results indicated that the growing season has advanced significantly in recent decades, which may be causing a mismatch between parturition and optimal resource availability. These effects may exacerbate the female's ability to meet the energetic demands of lactation. Therefore, the observed low calf survival appears to be caused by a combination of factors related to current land use and may also be due to changing vegetation phenology. These results have important implications for the management of species in human-dominated landscapes in the face of climate change, and for an increased understanding of how species may adapt to future land use and climate change.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Bader, Pekka, et al.
(författare)
-
Häckande kustfåglar på Holmöarna
- 2006
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Öar och skär i Norra Kvarken hyser ett rikt kustfågelliv och mångfalden av arter och antalet individerär intressant ur ett nationellt perspektiv. Stora delarna av Holmöarna avsattes 1980 till naturreservat,bland annat med utgångspunkt från områdets rika kustfågelfauna. Svärta och tobisgrissla ärtvå arter som förekommer i nationellt betydelsefulla antal i Holmöarkipelagen.Häckande skärgårdsfåglar bedöms vara en bra indikator för miljötillståndet och den biologiska mångfalden i skärgårdsmiljö. År 2000 påbörjades på allvar diskussionen om hur kustfågelfaunan på Holmöarna, men även i hela Norra Kvarken, på bästa sätt skulle följas upp och övervakas i ett långsiktigt perspektiv. Ett övervakningsprogram för häckande kustfågel ska kunna ligga till grund förbedömning av de nationella och regionala miljömålen samt bedömning av gynnsam bevarandestatus i Natura 2000 habitat. Ett nära samarbete kring dessa frågor finns med Finland inom Kvarken Miljö II, ett Interreg IIIA-projekt.Rapporten omfattar tre artiklar med fokus på häckande kustfågel i Holmöarkipelagen:Den första artikeln är en redovisning av de inventeringar som har genomförs i fyra områdenlängs Holmöarnas östra sida under perioden 2000-2003. Inventeringarna genomfördes av StoraFjäderäggs fågelstation i samarbete med och finansierat av Länsstyrelsen i Västerbotten och Umeåkommun. Utvärderingen av inventeringsresultaten gjordes av Pekka Bader och Joakim Lessmann.Den andra artikeln har författats av Lars Edenius och är en statistisk utvärdering av de inventeringarsom genomfördes under åren 2000-2003. Dessutom diskuteras i artikeln kustfåglars värde som indikatorför miljöförändringar i skärgårdsmiljö och där lämnas även ett förslag till upplägg av ett övervakningsprogramav häckande kustfågel på Holmöarna.Den sista artikeln, som är skriven av Lars Edenius, är en utvärdering av en metodstudie för inventeringav svärta som genomfördes inom Interregprojektet Kvarken Miljö II sommaren 2004.Kvalitetssäkring och harmonisering av inventeringsmetoder mellan Sverige och Finland görs i syfteatt i framtiden kunna etablera ett gemensamt övervakningsprogram för bland annat svärta i NorraKvarken.
|
|
| 6. |
|
|
| 7. |
- De Jong, Adriaan, et al.
(författare)
-
Tracing the origin of vagrant Siberian songbirds with stable isotopes: the case of Yellow-browed Warbler (Abrornis inornatus) in Fennoscandia
- 2019
-
Ingår i: Ornis Fennica. - 0030-5685. ; 96, s. 90-99
-
Tidskriftsartikel (refereegranskat)abstract
- Vagrant birds are mesmerizing birdwatchers worldwide, but the nature of vagrancy and the true origin of the vagrants are poorly known. To Western Europe, the massive Siberian land mass delivers most of the vagrant songbirds, e.g. Yellow-browed Warbler (YBW) (Abrornis inornatus, formerly Phylloscopus inornatus). In this study we used stable hydrogen isotope ratios in tail feathers (delta H-2(f)) from two ringing stations in northern Fennoscandia in an attempt to link vagrant YBW to potential regions of origin. We could do this thanks to a collection of samples from nestling and breeding adult YBW in Central Siberia. Compared with the nestling samples, the Fennoscandian delta H-2(f) data indicated origins in the western and/or southern parts of the breeding range. The assignment map created in IsoMAP showed high probabilities of origins in the Komi Republic, N/NW of the Ural Mountains. Although our study rules out a large proportion of the YBW breeding range, our method could not pin-point a precise region of origin. The main reason for this is the similarity of environmental hydrogen isotope ratios across longitudes in Eurasia. For increased precision, we propose a multi-method approach (e.g. stable isotopes and genetics) based on significantly more data from across the vast and challenging Siberian territory. More international collaboration will be vital for this endeavour.
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Edenius, Lars, et al.
(författare)
-
Bird communities of two forest types in Chitwan Valley, Nepal
- 2020
-
Ingår i: Ornithological science. - : Ornithological Society of Japan. - 1347-0558. ; 19, s. 29-40
-
Tidskriftsartikel (refereegranskat)abstract
- Maintaining biological diversity is an important objective at Chitwan National Park (CNP), the most visited national park in Nepal. Given human uses and manipulations of forests both in and around CNP, developing forest management guidelines that can both support human use of trees and sustain the biological diversity of the forests is a high priority. In Febniary 2009 we measured bird communities with point counts, woodpecker abundance with playback, and collected vegetation data in Sal Shorea robusta and riverine forests in CHP and a nearby community forest to provide basic data on bird-habitat associations with an emphasis on woodpeckers. Riverine forest had over twice the density of trees per ha (many small trees), higher tree species richness, and greater basal area than Sal forest. Sal forest had more large trees than riverine forest. We detected 71 bird species during the point counts in the study forests, 18 more during playback sessions, and an additional 12 species that were more associated with adjacent habitats (e.g., wetlands or flying overhead) for a total of 101 species. Among resident species, 31% were primary or secondary tree-cavity nesters. On average for point counts, we detected 29.5 bird species (2.2 woodpeckers) on transects located in riverine forest and 23.3 bird species (1.8 woodpeckers) in Sal forests, but the difference was not statistically significant. While riverine forest had several commonly occurring species not detected in Sal forest, the opposite was not the case. The regression of woodpecker species richness against large tree density in both Sal and riverine forests was positive, but not statistically significant. As a method of sampling woodpeckers, playback resulted in approximately twice the number of individuals and species compared to detection from point counts.
|
|
