Wednesday 17 December 2014

Woodcock Breeding

Following Tony's recent post on Woodcock this winter, I have more information on the 2014 breeding season. I have been in touch with Francois Gossmann who is the French Woodcock expert and his view is that although juvenile numbers are down this winter this does not represent a significant breeding failure and is part of the yearly fluctuation that happens due to the variation in weather conditions in Russia over the breeding season. This summer conditions in much of the area in Russia where Woodcock breed was dry, this impacted on the avialability of worms that are so vital for feeding broods.
I have also been in touch with Vadim Vitovsky a Russian biologist who studies Woodcock in the St Petersburg area. Each autumn they catch and ring Woodcock and have found that body mass this year was about 10% lower than normal reflecting poor feeding conditions, however Vadim also said that this was not an unusual occurrence.

Looking at the data on adult/ juvenile ratios from a selection of our ringers working in areas where there are few breeding Woodcock we can get a reasonable picture of what is happening with migrant woodcock for the past 4 years.

2011/12    65% juvenile  (sample 249)
2012/13    73% juvenile  (sample 178)
2013/14    70% juvenile  (sample 195)
2014/15    62% juvenile  (sample 144)  up to 12/12/14

Now that the Woodcock Network has a way of monitoring yearly breeding success we can keep shooter informed and urge them to use restraint on years when there has been lower breeding success. I have written a piece on this which will be published in 'Shooting Times' this week.

This is all possible due to the dedication of our Woodcock ringers who venture out on cold wet and windy winter nights to ring and gather this valuable information. People often question the need for ringing, but ringing Woodcock demonstrates the value of gathering biometric data across the country which can be used to the benefit of the species.

Since the Woodcock Network started ringing in 2008 we have learned that Woodcock are much more abundant than previously thought with our ringers seeing high numbers on sites throughout the country. What has also emerged is that migrant Woodcock are highly loyal to their wintering haunts. Since starting to ring Woodcock on my site in West Wales I have seen my re-trap level of birds ringed over previous winters grow each year.

2008/9     5.4%       of all adults caught
2009/10  11.3%       "         "            "
2010/11  29.4%       "         "            "
2011/12  30.5%       "         "            "
2012/13  47.0 %      "         "            "
2013/14  43.0%       "         "            "
2014/15  75.0%       "         "            "  up to 12/12/14

We are keen to get more ringers working on Woodcock so that we can improve our understanding of this secretive species. If you need advice on catching techniques please give me a call on 01974 272654.

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