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- Kleyheeg, Erik, et al.
(författare)
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A Comprehensive Model for the Quantitative Estimation of Seed Dispersal by Migratory Mallards
- 2019
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Ingår i: Frontiers in Ecology and Evolution. - : Frontiers Media S.A.. - 2296-701X. ; 7, s. 1-14
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Tidskriftsartikel (refereegranskat)abstract
- Long-distance seed dispersal is an important ecosystem service provided by migratory animals. Plants inhabiting discrete habitats, like lakes and wetlands, experience dispersal limitation, and rely heavily on zoochory for their spatial population dynamics. Granivorous waterbirds may disperse viable seeds of wetland plants over long distances during migration. The limited knowledge of waterbird migration has long hampered the evaluation of the importance of waterbirds in seed dispersal, requiring key metrics such as realistic dispersal distances. Using recent GPS tracking of mallards during spring migration, we built a mechanistic seed dispersal model to estimate realistic dispersal distances. Mallards are abundant, partially migratory ducks known to consume seeds of >300 European plant species. Based on the tracking data, we informed a mallard migration simulator to obtain a probabilistic spring migration model for the mallard population wintering at Lake Constance in Southern Germany. We combined the spring migration model with seed retention curves to develop seed dispersal kernels. We also assessed the effects of pre-migratory fasting and the availability of suitable deposition habitats for aquatic and wetland plants. Our results show that mallards at Lake Constance can disperse seeds in the northeastern direction over median distances of 293 and 413 km for seeds with short and long retention times, respectively, assuming a departure immediately after foraging. Pre-migratory fasting strongly affected the dispersal potential, with only 1-7% of ingested seeds left for dispersal after fasting for 12 h. Availability of a suitable deposition habitat was generally <5% along the migratory flyway. The high probability of seed deposition in a freshwater habitat during the first stopover, after the mallards completed the first migratory flight, makes successful dispersal most likely to happen at 204-322 km from Lake Constance. We concluded that the directed long-distance dispersal of plant seeds, realized by mallards on spring migration, may contribute significantly to large scale spatial plant population dynamics, including range expansion in response to shifting temperature and rainfall patterns under global warming. Our dispersal model is the first to incorporate detailed behavior of migratory waterbirds and can be readily adjusted to include other vector species when tracking data are available.
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| 2. |
- Poen, Marjolein J, et al.
(författare)
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Lack of virological and serological evidence for continued circulation of highly pathogenic avian influenza H5N8 virus in wild birds in the Netherlands, 14 November 2014 to 31 January 2016.
- 2016
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Ingår i: Eurosurveillance. - 1025-496X .- 1560-7917. ; 21:38, s. 11-21
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Tidskriftsartikel (refereegranskat)abstract
- In 2014, H5N8 clade 2.3.4.4 highly pathogenic avian influenza (HPAI) viruses of the A/Goose/Guangdong/1/1996 lineage emerged in poultry and wild birds in Asia, Europe and North America. Here, wild birds were extensively investigated in the Netherlands for HPAI H5N8 virus (real-time polymerase chain reaction targeting the matrix and H5 gene) and antibody detection (haemagglutination inhibition and virus neutralisation assays) before, during and after the first virus detection in Europe in late 2014. Between 21 February 2015 and 31 January 2016, 7,337 bird samples were tested for the virus. One HPAI H5N8 virus-infected Eurasian wigeon (Anas penelope) sampled on 25 February 2015 was detected. Serological assays were performed on 1,443 samples, including 149 collected between 2007 and 2013, 945 between 14 November 2014 and 13 May 2015, and 349 between 1 September and 31 December 2015. Antibodies specific for HPAI H5 clade 2.3.4.4 were absent in wild bird sera obtained before 2014 and present in sera collected during and after the HPAI H5N8 emergence in Europe, with antibody incidence declining after the 2014/15 winter. Our results indicate that the HPAI H5N8 virus has not continued to circulate extensively in wild bird populations since the 2014/15 winter and that independent maintenance of the virus in these populations appears unlikely.
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| 3. |
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| 4. |
- van Toor, Mariëlle L., et al.
(författare)
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Migration distance affects how closely Eurasian wigeons follow spring phenology during migration
- 2021
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Ingår i: Movement Ecology. - : Springer. - 2051-3933. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The timing of migration for herbivorous migratory birds is thought to coincide with spring phenologyas emerging vegetation supplies them with the resources to fuel migration, and, in species with a capital breedingstrategy also provides individuals with energy for use on the breeding grounds. Individuals with very long migrationdistances might however have to trade of between utilising optimal conditions en route and reaching the breeding grounds early, potentially leading to them overtaking spring on the way. Here, we investigate whether migrationdistance afects how closely individually tracked Eurasian wigeons follow spring phenology during spring migration.Methods: We captured wigeons in the Netherlands and Lithuania and tracked them throughout spring migration toidentify staging sites and timing of arrival. Using temperature-derived indicators of spring phenology, we investigatedhow maximum longitude reached and migration distance afected how closely wigeons followed spring. We furtherestimated the impact of tagging on wigeon migration by comparing spring migratory timing between tracked individuals and ring recovery data sets.Results: Wigeons migrated to locations between 300 and 4000 km from the capture site, and migrated up to1000 km in a single day. We found that wigeons migrating to more north-easterly locations followed spring phenology more closely, and increasingly so the greater distance they had covered during migration. Yet we also found thatdespite tags equalling only around 2% of individual’s body mass, individuals were on average 11–12 days slower thanring-marked individuals from the same general population.Discussion: Overall, our results suggest that migratory strategy can vary dependent on migration distance withinspecies, and even within the same migratory corridor. Individual decisions thus depend not only on environmentalcues, but potentially also trade-ofs made during later life-history stages.
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