Hampshire Atlas – Winter Pilot Survey
In the winter of 2005/06, some 40 intrepid volunteers made a fairly intensive Atlas-type survey of a single 10-km square. The 10-km square was SU52, the area bounded roughly by Marwell – Cheesefoot- Cheriton- Corhampton. We chose this square partly because it is the nearest square to the centre of the county, partly because it’s a square not normally well covered, and partly because it’s fairly typical of much of Hampshire.
The purpose of the exercise was to test some of the methodologies that may be used in the forthcoming national & county Atlas projects (starting in November 2007). Members of a "Tetrad Team" of observers confined each of their visits to a specific tetrad (2km x 2km square), and they recorded birds seen in each 20-minute period. Two visits, mostly of 3 hours, were made to each of the 25 tetrads in the 10-km square. People in a "Rover Team" team had a much more flexible brief, and went wherever they chose within the 10-km square, for whatever length of time, and making as many visits as they wished.
First, some statistics:
Tetrad Team Rover Team Total
Number of observers 22 11 33
Number of visits 49 66 115
Number of hours 142 154 296
Number of species 74 77 81
It definitely was intensive coverage, and I’ll doubt we’ll be able to do that for every square in the main Winter Atlas!
I guess the most interesting thing, was that the overall total and range of species was very similar for both rovers and tetrad people. This wasn’t too surprising given the total time spent, and that both teams spent roughly the same time overall. The results from tetrad people, gave a better picture of bird distributions, whereas the rovers were much better able to seek out specialist species like wetland birds and owls
What about the species ?
Well, there were no great surprises. Water birds were of course hard to come by, with only a tiny bit of water in the whole square. The rover team were able to concentrate a bit more time on this aspect, and were able to record a few species not encountered by the tetrad team - singles of Mandarin, Tufted Duck, Green Sandpiper and Kingfisher. Of the widespread birds, Woodpigeons were of course the most numerous, and on their second visit, over 8,000 were recorded by the tetrad counters. Specialist farmland birds included plenty of Yellowhammers, but relatively few Grey Partridge, very few Corn Buntings, and no Tree Sparrows at all. Skylarks flocks were relatively few in number, perhaps because the square is relatively well-wooded. But pleasingly, and presumably for the same reason, farmland Woodlarks were reported from several widely spread locations. Of the finches, Bramblings were more numerous than Greenfinches and Linnets, and there was a scattering of Reed Bunting and Redpoll. There were several small flocks of Fieldfare, but Redwing were decidedly scarce. Some lucky participants were able to see flocks of Golden Plover, and other "nice" sightings included Peregrine, Red Kite, Lesser Spotted Woodpecker, and Hawfinch.
There is a lot of interest in the detail, and a fuller report appeared in the 2006 Hampshire Bird Report.