Phylosc's, Acro's and lovely lady Sylvia

Adam Homer writes:

The numbers of warblers ringed at Stanford Reservoir, Northants has increased significantly over the last 5 years. An annual habitat management plan allows us to control tall scrub which then allows low scrub and vegetation such as Brambles, Hawthorn, Sedge and Phragmites to regenerate. This as we all know is very important habitat for breeding birds such as warblers.

A site that is as far inland from any coastal observatory that you could get, Stanford Ringing Group prides itself on the numbers of warblers caught annually. Over 3,600 warblers were ringed in 2014 and already this year we have ringed nearly 3,800 and we still have October to catch a few more Blackcap and Chiffchaff.



With all these warblers ringed and eventually setting off on their migration we do receive a few reports of birds controlled (caught by another ringer >5km from ringing site) and we occasionally control birds ringed at other sites. Every spring we also retrap some of our returning warblers and to me that is what bird ringing is all about. That a small bird such as a Garden Warbler or Willow Warbler can fly a round trip of 3,000 miles and return to the site it has been breeding at for 10 years in a row is amazing!

Garden Warbler taken by Lee Barber (tail obscured)

One of these record-breakers was once again retrapped this year. It was a Garden Warbler that was ringed as an adult female on 2 July 2005. She then disappeared for two years, returning in 2008 and retrapped every year since. I was on holiday when she returned this year and was caught during two of our CES sessions. On 8 August she became the longest known BTO-ringed Garden Warbler at 10yrs and 37 days, breaking the longevity record for this species by 7 days*.

			Year
	2011	2012	2013	2014	2015
Garden Warbler	84	42	66	108	116
Blackcap	710	205	402	1665	1608
Lesser Whitethroat	50	26	56	81	109
Whitethroat	491	261	480	455	469
Sedge Warbler	259	67	145	140	190
Grasshopper Warbler	17	3	2	1	1
Reed Warbler	287	87	242	246	314
Willow Warbler	192	224	178	215	215
Chiffchaff	379	178	388	717	741

 

As you can see from the table above, the numbers of warblers, particularly Blackcap and Chiffchaff, have increased significantly with Garden Warbler and Lesser Whitethroat also showing a positive upward trend.

*Eds - The longevity records will be updated when all the 2015 data has been sent to the Ringing Scheme and fully processed. This longevity record will then replace the previous longevity record... unless another ringer catches an older bird or Stanford Ringing Group catch this Garden Warbler again a few days older.