2012 has been a difficult year for many CES sites, the weather making the 12 visits required hard to achieve and catches lower than normal.
At Heysham we did achieve the 12 visits, largely because we are normally able to pick any day of the week, unlike ringers who may be confined to weekends. Catches were not particularly low either (for this site) at 134 new-for-year birds.
Birds captured in all 12 visits have ranged between 85 and 146 over the last 13 years. These overall numbers are terribly low for the effort involved and are way below the recommended level of 250 new-for-year birds, but the BTO tell us that it is still a viable site producing useful data so please 'Keep Going'. I am often amused by comments in CES News where ringers complain of poor catches in a visit that are more than our yearly catch - the chance would be a fine thing!
Numbers of local breeding birds such as Blackbird, Dunnock and Wren were up this year with plenty of young captured. Blackcap numbers were reasonable with 4 birds being retrapped indicating breeding on the site. Bullfinch are always caught in reasonable numbers and this year was average. Common Whitethroat were down with only a single young bird caught as were Lesser Whitethroat (7 were caught, of which 4 were juveniles, with no retraps). This latter species normally breeds on the site and more are trapped. Chiffchaff, at 14, were up on last year.
ajd
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