The wind was too high to attempt catching again, but I filled the feeders up anyway - the fat ball that went up after dark on thursday had been completely consumed by friday lunchtime!
The wash trip a few weekends ago was a good success - 177 Oystercatchers on the Saturday morning (all of a good mass) and 2 oystercatchers and a knot on Sunday. These Oystercatchers were not in such good condition, weighing far less (although obviously the sample size was small and a pair of Peregrines had chased most of the birds off the beach by the time we fired). We also found a dead oystercatcher on the beach with the sharpest keel imaginable! It displayed arrested moult (where the bird has stopped growing feathers half way through its moult and instead retains its old ones) - leaving us in little doubt that this bird had starved to death.
There has been interesting research on waders collected by ringers* during harsh winters. Some waders (such as Grey Plover) weigh less on capture compared to a 'normal' year - they appear to be struggling to find food resources enough to put on enough weight. Other waders (e.g. Dunlin) instead increase their mass in colder weather - if they put on more mass then they are at a lower risk of starvation.
I am looking for some wader and/or seabird ringing for this spring/summer - please let me know if you've heard of anything. Must not be too expensive and preferably last more than a month.
*from WWRG - I'm not sure exactly who but I'm sure it includes the Clarks, Phil Ireland and Jen Smart amongst others
Monday, 7 February 2011
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