Thursday, 29 October 2015

Oxwich Marsh 25 - 28 October 2015: autumn thrushes

Late October has seen unsettled, but not particularly wild weather, with varying wind speed and short periods of rain.  In the calmer periods we have been able to get a couple of ringing sessions in. During the first of these a light to moderate south-easterly wind meant we restricted our netting to areas of sheltered scrub, while during the second session a light south-westerly wind allowed us to ring in the open reedbed.  We were hoping (in particular) to catch some redwing, as large numbers are moving through at present.

The combined results of the two sessions were as follows:

Species
New
Re-trapped
Total
Wren
5
0
5
Dunnock
1
1
2
Robin
0
4
4
Blackbird
3
0
3
Song Thrush
2
1
3
Redwing
62
0
62
Cetti's Warbler
0
1
1
Chiffchaff
1
0
1
Goldcrest
16
2
18
Firecrest
1
0
1
Long-tailed Tit
7
1
8
Coal Tit
0
1
1
Blue Tit
21
13
34
Great Tit
3
5
8
Chaffinch
8
1
9
Greenfinch
4
0
4
Goldfinch
8
4
12
Reed Bunting
9
5
14
Total:
151
39
190

The highlights over the combined visits were an excellent catch of 62 redwing, continued good numbers of goldcrest (taking us to 135 individuals captured this year), a first winter male firecrest (the third of 2015) and a steady, light stream of reed buntings.

The redwing were moving over the marsh in large numbers on the morning of 28 October, and the use of the much vaunted Latvian lure proved very effective.  Flocks of 60-80 birds were regularly seen milling around before moving away west.  Birds were trapped over a period of three hours, with the period between 15 minutes before dawn and two hours after dawn being the most productive.

It may be of some interest to note that while the first twenty or so redwings we trapped this autumn were roughly evenly split between first winter and adult birds, the last 60 have been approximately 2:1 (1st winter to adult).  Wing length varied between 111 mm and 126 mm and weight from 54.2 g to 69.9 g on 28 October.  Very few were carrying visible fat, with a maximum score of 2 recorded (based on the British Working Group (BWG) fat scoring system).

Reed bunting is one of the target species at the marsh.  We will probably ring in the region of 140 birds this year (124 to date), as well as processing birds ringed in 2014 and before (we have caught a further 24 birds ringed in previous years in 2015).  It has been nice to get some recent news of reed buntings controlled at other sites, albeit these have been from the north side of the Burry Inlet (Cefn Sidan) by Paul Aubrey and at Nitten Field, Mewslade by Barry Stewart.  Hardly international movements.  However it is very clear that numbers in the marsh fluctuate, sometimes unexpectedly, and it will be very interesting to build up a data set on them over the coming years.

During the first of the two sessions we were visited by former Wicken Fen ringer David Butler and family.  Luckily their arrival corresponded with a varied catch, allowing the children to see a number of species (mainly tits and finches) up close, and also the firecrest just prior to its release.

Many thanks to Wayne Morris, Emma Cole, Paul Aubrey and Dan Rouse for their help on Sunday, and to Charlie Sargent and Darren Hicks for running the Wednesday session.  Some really good late autumn results.

A photo of one of the redwings is below

Owain Gabb
29/10/2015


1 comment:

  1. Thanks Owain and team for your generous time and hospitality, we all had a great experience, the children especially enjoyed seeng the birds up close and I enjoyed reminiscing about how painful Blue Tits can be and seeing a Firecrest in the hand. Regards, David

    ReplyDelete