Wind and rain inflenced our ringing activities more than our AI precautions did. In the end we 'lost' two nights and spent two nights on the beach - to avoid the wind. We only managed one night on what is one of our more productive sites.
To cut a long story short our captures were the worst on record for over a decade. Having taken, and expected to use, a large number of the 2500 rings taken we only managed 152 new birds, 9 UK recaptures and one Norwegian ringed bird! In any previous year we would have caught this number in a couple of hours.
Why was this? Obviously the first thing that springs to mind is AI (storm petrels being essentially pelagic may hide mass deaths at sea), however some live sampling of petrels at Mousa returned that all were negative for AI. The next option is the reported and unusally high sea temperatures. The thinking here is that the food source of plankton/krill is considerably further north in cooler waters and that petrels staying with their food source are then much (much) further from land precluding succesful breeding. As such many have not attempted breeding and are therefore not coming to land (to be caught). Let's hope this is the case, next year may be able to answer this question.
However, out of this the lower catch rate there were other benefits. Currently we are trying to build a mechanism for being able to sex storm petrels (nearly all are not). So, with lower numbers, we were able to take a full set of biometrics, photograph, examine for brood patches and take feather samples (under license) on virtually all birds to collect data which may eventually lead to guidelines for phenotypically assigning sex to storm petrels.
An envelope containing plucked feathers and an underwing photograph of the same bird to determine the extent of underwing 'white'.
The Team this Year.
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