The effects of disturbance caused by boating on survival and behaviour of velvet scoter Melanitta fusca ducklings
Mikola, J.; Miettinen, M.; Lehikoinen, E.; Lehtilä, K. (1994). The effects of disturbance caused by boating on survival and behaviour of velvet scoter Melanitta fusca ducklings. Biol. Conserv. 67: 119-124. https://dx.doi.org/10.1016/0006-3207(94)90356-5
In: Biological Conservation. Elsevier: Barking. ISSN 0006-3207; e-ISSN 1873-2917, more
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Keywords |
Countries > Developed countries > British isles > European union countries > Oecd countries > Commonwealth of nations > Uk > Great britain > Scotland Interspecific relationships > Predation Scotland Finland [Marine Regions] Marine/Coastal |
Authors | | Top |
- Mikola, J.
- Miettinen, M.
- Lehikoinen, E.
- Lehtilä, K.
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Abstract |
We studied the consequences of human disturbance and gull predation on brood survival of velvet scoter Melanitta fusca in the Archipelago of South-West Finland in 1990 and 1991. Each brood was exposed to disturbance by boats on average 8.5 times a day in 1990 and 3.5 times a day in 1991. Disturbance lengthened the swimming distances of ducklings and reduced the time used for feeding. Broods disturbed more frequently than average were smaller than those disturbed less frequently. At least 60% of ducklings died before the age of three weeks. The common predators of ducklings in the study area are the herring gull Larus argentatus and the great black-backed gull Larus marinus. The daily predation rate by gulls on velvet scoter ducklings was 4.7%, which means that 56% of ducklings are caught by gulls during the first three weeks. The frequency of gull attacks was 3.5 times higher in disturbed than in undisturbed situations. |
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