Geoscience Reference
In-Depth Information
intensity of swan grazing and movements of the
foraging birds. Swan grazing typically occurs from
May to September and involves several flocks
(Trump, 1996), so a more comprehensive IBM
which covers an entire year and involves larger
areas of river catchment is required if the model is
to be applied effectively. Elsewhere, the versatility
of IBMs has been demonstrated by their use in
predicting the effects of environmental change
on a range of animal populations, including
river-feeding swans, coastal wading birds and
invertebrate-feeding fish (Stillman and Goss-
Custard, 2010; West
et al
., 2011). IBMs can
also be used in freshwater ecosystems to model
resource-consumer interactions. Such models
could be used in a decision-support role and
should be of particular interest to those with
wildlife, environmental and fisheries interests
involved in river conservation and management.
conservation of natural habitats and of wild fauna and
flora.
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, Environment Agency,
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O'Hare MT, Stillman RA, McDonnell J, Wood LR
(2007) Effects of mute swan grazing on a keystone
macrophyte.
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Stillman RA (2008) MORPH - an individual-based model
to predict the effect of environmental change on
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Acknowledgements
The authors thank the Freshwater Biological
Association for access to the river. Kevin Wood was
supported by a Centre for Ecology and Hydrology
Algorithm (Natural
88
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2926-
35.
van Gils JA, Beekman JH, Coehoorn P, Corporaal E,
Dekkers T, Klaassen M, van Kraaij R, de Leeuw R, de
Vries PP (2008) Longer guts and higher food quality
increase energy intake in migratory swans.
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West AD, Stillman RA, Drewitt A, Frost NJ, Mander M,
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WaderMORPH - a user-friendly individual-based
model to advise shorebird policy and management.
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Environment
Research
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