Thursday, 27 June 2013

End of the year report.

No I'm not going crazy. I know it's only June, but for the birds using the nest boxes at Linacre this year, it is the end of the breeding season. I went down last night to ring the last 2 remaining broods, 1 of 7 Blue Tits and 1 of 5 Great Tits, so I thought I'd give you a round up of this year's highs and lows.

Thankfully this year, the highs have far outweighed the lows. Over the last month or so we've had 28 tit boxes and 2 owl boxes used, which is a 33% occupancy rate. Of the 28 tit boxes used, 25 were successful and only 3 failed before the young birds could be ringed. Obviously, not all the birds have fledged yet, so there could still be some more deaths before the birds fledge.

Blue Tits used 19 boxes, 18 of which were successful and brood sizes ranged from 3-12 chicks, with the mean being 7. Great Tits used 9 boxes, 7 of which were successful, again with a  range of  3- 7 chicks, the mean being 5. A total of 166 tit pulli have been ringed from the boxes (129 Blue Tits and 37 Great Tits), which is 20 more than last year.

Two of the three owl boxes were used by Mandarin Ducks this year. As a group, we managed to ring both female birds. Both boxes contained between 10 eggs and, after fledging, just 2 eggs were found in one box and one dead chick was found in the other, giving a successful fledging rate of 80% and 90% respectively. At least 2 broods have been spotted on the reservoirs already this year, and we look forward to seeing if the female bird will breed again in the boxes in 2014. The third owl box wasn't used for breeding this year, but a Tawny Owl was present in it in April, so again, fingers are crossed for next year. The Kestrel box was occupied by Grey Squirrels again this year!

Away from the boxes, the only open nest found was that of a Song Thrush. Four eggs were found on 12th May (see here). Four chicks were seen later in the month and three were ringed in early June (see here). The nest is now empty, so hopefully the birds fledged successfully.

The final nest that we managed to monitor and ring birds from was a Little Owl nest found in a tree by the entrance. The first reports of Little Owl came in summer last year, and a pair was spotted in the same set of trees throughout the Spring. In May we checked out a possible nest site and ringed the female bird (see here), and then one chick from the nest on 16th June (see here).

Nests that were seen, but not ringed, included 2 Great-crested Grebes and 1 Little Grebe, but I'll update these as the summer progresses. Now all we want is to recapture some of this year's birds over the winter period and, hopefully, using the boxes again next year.

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