There is no doubt what the headline species, in terms of numbers has been so far this year, and that is Willow Warbler. We have continued to catch good numbers this week, with another 37 added which brings the total this year to 222. This is already by far the best annual total for the site ever, which surely must indicate a good breeding season for the species.
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Juvenile Willow Warbler - one of 19 caught today |
Grasshopper Warbler numbers have also started to build this week with 69 new birds added. The total of 31 birds ringed on 23rd included six adults, which were the first of the year. Adult and juvenile Grasshopper Warblers undergo a partial post juvenile or post nuptial moult. In juvenile birds this is not really obvious as all the feathers are fresh, but in adults it results in a mixture of new, fresh feathers and very tatty, worn feathers. There seems to be no strategy as to what feathers are replaced, as throughout the body, head, wing and tail feathers, random feathers can be replaced. The Images below illustrate this.
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Adult Grasshopper Warbler crown, note mixture of new (fresh) and old (worn) feathers |
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Very worn wing feathers of the adult Grasshopper Warbler |
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Very worn tail feathers of adult Grasshopper Warbler |
Of the other key warbler species, Sedge Warbler numbers are on a par with the record numbers of 2011 and 2013, and Reed Warbler numbers are the highest of the last five years. Garden Warbler numbers are also on a par with the record year of 2011 and Blackcap numbers are significantly higher than at this point in any of the last five years. Chiffchaff and Whitethroat are also high and are the second highest totals in the last five years for both species. Cetti's Warbler numbers are also the highest of the last five years, although the numbers have slowed in recent days as the breeding birds have moved away from the ringing area and into the reed beds.
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Table summarising key species total up to 23rd August in the last five years |
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Graph illustrating key species totals over the last five years. |
Other notable species ringed this week were the second Lesser Whitethroat and Treecreeper of the year. Both species are only ever trapped in small numbers at The Haven.
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Juvenile Lesser Whitethroat - the second of the year |
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Treecreeper - the second of the year |
We had ringed over 220 birds by the end of the session 23rd August. Sedge Warbler (still no Aquatics) was the most numerous species with 69 birds ringed, followed by Reed Warbler (46), Blackcap (35) and Grasshopper Warbler (31).
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