As I mentioned in a previous post, the autumn migration is pretty much over and so with very few birds passing through the ringing area at Titchfield Haven, it was time to call it a day, well season. Overall it was an interesting year that was made all the more frustrating by some very variable weather conditions, but whilst there were some very low totals for some species, others had a record year.
Selected Annual Ringing Totals Titchfield Haven 2012 |
The season finished with a total of 2579 birds ringed between early July and the end of October 2012, with the most numerous species ringed being sedge warbler (635), followed by blackcap (371), grasshopper warbler (360), reed warbler (304) and chiffchaff (291). I have previously discussed what a fantastic year 2011 was totals wise, and the following graph and table illustrate this.
Five Year Totals for Selected Species |
During 2011, 1436 sedge warblers were ringed in the autumn period, during 2012 only 635 were ringed, 44% of the 2011 total. Grasshopper warbler followed a similar pattern, with the 2012 total being only 38% of the 2011 total. The totals for whitethroat, garden warbler and chiffchaff were equally low with the 2012 totals being 22%, 27% and 34% of 2011 totals, respectively.
Five Year Totals for Selected Species (the figures in red represent the highest annual total for that species) |
But whilst the totals for many species were much lower, common redstart and firecrest had their highest ever totals this year with five and seven, respectively ringed. Blackbird and song thrush totals were the highest for over 10 years, although the numbers of birds ringed were still fairly low. Overall the 2012 total was the lowest autumn total at Titchfield Haven since 2006.
Annual Titchfield Haven Ringing Totals 2008 - 2012 |
Given the above results it would appear that several bird species suffered poor breeding success during the summer of 2012. It is considered that the poor weather conditions throughout the breeding season may have been a contributing factor, but poor weather over the Mediterranean during the spring migration may have meant that less adult birds returned to breed. The recently published State of UK's Birds 2012 report details that the number of breeding birds in the UK has declined by 44 million since 1966. Changes in land use and management, and loss and fragmentation of habitat have been cited as some of the reasons for the decline, along with cold and wet weather. Given the apparent effect the weather this summer has had on breeding birds, the declines of some species could be much faster if the trend of colder and wetter summers continues.
Interesting reading Trevor - Thanks
ReplyDeleteAndrew