Remember there are whimbrels! (sung to the humble tune of the wombles)Everyone knows about whimbrels... right? They are fictional furry creatures that live in burrows, helping the environment by collecting and recycling rubbish in useful and ingenious ways... and they live on Wimbledon common...oh no wait, that’s the Wombles. Whimbrels are not like that at all, they are wading birds, very much more like a smaller, darker version of the more familiar curlew, however, they are a lot more often overlooked.
Why do we overlook whimbrels?The whimbrels long beak, is used to pick and probe for crustaceans, beetles, flies, spiders, leatherjackets, worms and some plant material such as berries. They breed on moorland, often in slightly harsher and wilder areas than the curlew. Whimbrels breed only in the very far north of the UK, on Orkney and Shetland, where the whimbrel arrival heralds the start of spring, and their distinctive 7 note call is often the best clue to its presence. They may be seen further south outside the breeding season during migration, on estuaries, saltmarsh, coastal lagoons and rocky shores. However, most will not linger, as they migrate to their wintering grounds in Africa.
Not so numerous Numenius phaeopus Once upon a time, well since the 1930s, whimbrels had increased in number and expanded their range, but recently this has been reversed, and evidence has now emerged of large declines on sites throughout Shetland. On the core breeding areas of Fetlar and Unst since the 1980s/early 1990s there's been a terrifying 71% decline on Fetlar, 36% decline on Unst, and a 40% decline across Shetland as a whole.
Still whimbreling aroundIt was however heartening to hear of an ancient whimbrel that was found on Shetland recently, some 24 years after it was ringed by Durham University! It is probably at least 26 years old, and must have flown an astonishing distance on it’s many migrations. It could be giving Great Uncle Bulgaria a run for his money.
Why oh why whimbrel?The reasons for their serious decline are currently unknown, however, there have been significant changes in abundance and behaviour of predator species. For example, great skuas population and range is increasing, this in turn is also displacing Arctic skuas, which nest alongside whimbrel and provide extra defence against predation by the great skuas. It is also possible that a reduction in sandeel stocks means that Arctic skuas are now relying more on eggs and chicks of whimbrel and other waders as food.
The north sea is experiencing major regime changes, and instability in the food web, which is ultimately being driven by climate change. Whimbrel are at the southern edge of their breeding range in the UK, making the population potentially vulnerable to the effects of climate change. As so little is known about the causes of whimbrel declines research is urgently required, before too few birds remain to enable research of any value.
Whimbrel whimsy comes trueAdvocacy work to retain suitable habitat, and working with farmers in areas with breeding populations, are important conservation measures until research can provide more answers. However, lack of knowledge on causes of decline means there is limited basis for advocating appropriate management interventions, or to use the decline to help with policy initiatives (eg climate change, marine issues).
The desperate need for research into these declines has sparked an exciting new project on whimbrel, which has commenced this year! The project aims to compare breeding success and causes of breeding failure during the current period of decline, with these same factors during the mid-1980s when the population was increasing, and between areas currently with and without declines.
How will we find this out ?Research began in May 2010 on the islands of Fetlar and Unst, the core breeding areas within the Shetland Isles during the 1980s which held >40% of the population. Nests are located and monitored until chicks hatch or the nest fails, and adults are caught and colour-ringed to allow individual broods to be monitored following hatching until they fledge or fail. Where possible, causes of nest failure or chick mortality will be determined. Catching adults will also allow assessment of evidence for changes in body condition, and colour-ringing will enable annual survival rates to be assessed.
Further work proposed would entail analysing the data to establish the full extent to which whimbrel declines are related to changes in the abundance of skua species. Overall, the research will establish whether management solutions are feasible. This work may provide valuable input to policy on climate change, and the marine environment if declines are found to be associated with changes in skua populations and foraging behaviour.
Out on a whim-brelI think we need to increase the whimbrel profile somewhat - and perhaps the wombles offer a good model for fame. We ought to create a children’s TV show about a family of whimbrels on Shetland, call it The Whimbrel Whimsy and be done with it! I think the main the character should be called Tang Whaup, which is by far the best historic name I could find. Any takers?