01 October 2015

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.

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