Avon BTO

Friday, May 30, 2008

Breeding season so far

A brief summary of the tetrad and Roving records inpout so far . There are some 50 paper forms not included.
There are returns for 17 10km squares ( not ST37), and the number of species reflects the number of tetrads surveyed. 146 species have been seen, with an average of 68. 99 of them were possible breeding species (of which 58 have been confirmed as breeding in at least one square).ST57 has 70 btreeding species, ST58 69. 12 species have been proved in every square, a further 10 in 16/17, and 19 in only one square. It is important that birds that are not yet breeding (?Little Egret ? Siskin) or that have ceased to breed (? Redshank, ?Snipe ? Wheatear ?Redstart) are not put in the possible breeders (ie observed in possible breeding habitat) unless you are pretty sure that are breeding.

One point checking through the records. Occasionally observers say they have recorded for Two hours, but only enter totals for a single hour. This creates problems, because this survey is designed to be compararble fwith the last breeding survey which only asked for ONE hour to be spent in a tetrad twice- but the recording was presence absence not counting. Because the total species seen increases with time spent, and the requirement to count increases the time needed, the First hour species list will be compared with the last breeding Atlas- but the two hours together can be compared with this winter Atlas.

Please enter all first counts that have been recorded, and good luck with the second ones.


Post a Comment

<< Home