|WHAT IS ALREADY HAPPENING||WHAT COULD HAPPEN|
- Poor breeding success, reduced survival and population declines of black-legged kittiwakes in recent years have been strongly linked to climate change, in particular to warmer winters and reductions in availability and nutritional quality of their fish prey (e.g. sandeels). Evidence suggests other species may have been similarly affected.
- In 2006 and 2007 poor breeding success at some colonies of kittiwakes and other species such as puffins coincided with a dramatic increase in the number of snake pipefish being brought back to feed chicks. Snake pipefish are virtually indigestible and can choke young chicks. No link has been established between climate change and the sudden occurrence of snake pipefish in UK waters in 2003.
- Colonial breeding may make it more difficult for some species to adapt to climate-induced changes in prey availability.
- Continued poor breeding success and reduced survival will lead to further declines in some seabird populations in the short and long term.
- Long-term climate change will result in the northwards contraction of the range of some species and consequently a decline in population size.
- Anticipated sea-level rise and increased storminess may reduce available breeding habitat for shoreline-nesting species (e.g. terns) and wash away nests.
|what is happening now||what could happen in the future|
|Amount of evidence||moderate||low|
|Level of agreement or consensus||high||moderate|
|Level of confidence||medium||low|
- Too little is known about seabirds, their diet, fish abundance and plankton ecology in areas outside the North Sea, particularly off the west coast of Scotland. Survey coverage should be improved in this area. Better survey coverage of e.g. seabird demography and phenology would also be extremely valuable, and would allow the generality of findings from a few highly detailed studies to be assessed.
- The response of seabird prey, i.e. mostly small fish such as sandeels, to climate change is not at all well understood. We need to know why recruitment of sandeels and possibly other species seems to be negatively affected by warmer winters. Likewise, we need to know whether the recent population explosion of snake pipefish is linked to climate change.
- A better understanding is needed of how individuals respond to climate change. Seabird populations consist of very long-lived individuals, and their ability to cope with climate change at the population level will to a large extent be determined by how individuals respond. The options for micro-evolutionary change may also be constrained by social interactions among individuals. Resolving these questions will require detailed long-term studies of marked individuals.
A potential major decline in breeding seabirds would be likely to affect the ecotourism industry, particularly in Scotland.
Seabird Colony Team Leader, Joint Nature Conservation Committee (JNCC), Dunnet House, 7 Thistle Place, Aberdeen AB10 1UZ.
Senior Scientific Officer, Coastal Seas Ecology Group Centre for Ecology and Hydrology (CEH), Hill of Brathens, Banchory, AB31 4BW.