Avon BTO

Monday, March 02, 2009

The breeding season beckons

To date we have got records for 343 tetrads. In the last week 14 new tetrads have been entered- there are another 28 I am waiting for, and I will be jogging a few observers for their records soon. Paper records are starting to roll in, and I will do a summary of this winter for anyone interested. All being well we will have covered all but a dozen of our 400 tetrads this winter.
I have a number of impressions- how few BH there have been, how very thin MP are spread, how low GR counts are, how amazingly widespread RN and BZ are ( 75% of tetrads in some 10k squares), how few, by contrast, PE are seen. It will be fascinating to see the statistics. I am working on three main figures for each species for each 10k square- % distribution, max number/tetrad and overall rate/hour. Another interesting figure is average species per tetrad, which is running at around 35, and, with 400 tetrads is a fairly powerful figure to play with, and also average maximum numbers per tetrad, which varies between 500 and 1100, averaging around 700; That gives a figure of c280,000 birds counted for the region- how that translates into actual population estimate is another matter!

For the breeding season I have prepared a Breeding Status list for each 10KM square, which I will send out to those doing tetrads in them, and to others who did them last season because this is where Roving Records come into their own. We need to ensure confirmed breeding status for every species that is possible, and also to ensure that those species that are non breeing are identified as M (migrant) or U (summering/non-breeders). My lists make it clear what needs to be done, and anyone can contribute information at any time for any area of the region for which they have evidence. Also there is a new facility on the website, Any Square summary- which allows you to see the maximum breeding status of every species in any square you are interested in.
Incidentally Proved breeding records for early nesters for March can be entered and will be used.


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