Monday, February 1st, 2016
On the Trail of Filey Rails
Currently almost all ringing effort in Filey has been centred on passerines or near-passerines, with occasional wader and storm petrel ringing. To try and gain a more holistic view and gather important data on other species particularly wildfowl and rails (both of which receive relatively limited ringing data in Britain) we decided to put out some walk-in-traps at wetland sites within the bird observatory. These traps are relatively unobtrusive and are tucked away into reedbeds and areas of rush growth, the birds simply walk in and are held by a one-way door, before being rung then released back on site.
Species like Water Rail are incredibly secretive and have limited amounts of information on their migration patterns documented. Small scale movements, either in response to environmental conditions or post natal dispersal needs additional information. Other gaps in our knowledge of these birds include whether the winter migrants which return to central Europe from Britain do so on a loop migration or use alternative strategies. To find answers to this and other similar knowledge gaps we need to ring more birds and gather more data, subsequently if we can contribute to this and allow more recoveries we may help in the conservation and knowledge about species like this.
Currently within the bird observatory we appear to have quite good numbers of wintering Water Rails with birds spread across numerous sites. Filey Dams for example currently has at least 3 wintering birds. A much higher turnover of birds could potentially use sites within Filey, meaning Filey could potentially be an important staging point for migrant birds (as well as our resident breeders) dispersing into the wider vale of Pickering and York areas (or beyond). A trip to Filey dams around dusk is likely to result in the pig like squealing of rails in the reedbed to the left of the main hide, where an adult female has set up her winter territory. At least another bird occasionally goes into the reedbed which creates quite a commotion, when these territorial birds meet.
An often overlooked relative of the Water Rail is the Moorhen, like its smaller relative the largely sedentary British population is joined by immigrants from other parts of north-west Europe. With numbers augmented during the winter the Filey wintering population of this species is often very impressive. Also like its smaller relative very little ringing data is collected nationally per year in comparison to other species. Ringing in Filey gives us an excellent opportunity to study this species as both birdwatchers and ringers. Initially the project looked at establishing whether or not moorhens were easy enough to catch to study.
Fortunately we have found them to be relatively straightforward, so the next stage in accordance with the BTO is making them easy for bird watchers to identify as individuals. This will be done with the use of darvic rings which are more easily read in the field compared to traditional metal rings. Hopefully this will help aid our recovery information and gain more of an understanding where the birds in Filey originate from and where they go, how long they live, breeding strategy and causes of morality. It is likely that colour ringed (darvic ringed) birds will start to appear on the Dams next winter as we will soon be finishing ringing to allow them the opportunity to breed undisturbed from March onwards.