Thursday, 31 March 2016

Oxwich Marsh 31 March 2016: interesting recaptures

An overnight frost made for a cold start at the marsh. We put out 340 feet of net, most of which was across the open reed bed. The catch was very modest and is detailed in the table below:

Species
Ringed
Recaptured
Total
Sparrowhawk
0
1
1
Great Spotted Woodpecker
0
1
1
Wren
0
1
1
Dunnock
0
2
2
Chiffchaff
0
1
1
Goldcrest
1
0
1
Blue Tit
1
2
3
Great Tit
0
2
2
Chaffinch
1
0
1
Goldfinch
4
0
4
Siskin
3
2
5
Reed Bunting
1
4
5
Total:
11
16
27

Despite the low numbers there were several interesting features, however. The first was a chiffchaff initially ringed on the marsh in early April 2015, recaptured later the same month (by which time it could be sexed as a male), and then recaptured again this morning. Nice to see a returning bird, and hopefully we can recapture it again later in the season to prove local breeding.

The second was evidence that we are getting a lot better at ageing reed buntings. At this time of year the degree of feather wear in both adult and first winter reed buntings is considerable, but the breadth and shape of the tail feathers and tertials can still give a good indication of age. We tend to enter all but the most extreme birds as being of unknown age from early in the new year onward, but also record our assessment of what age each bird is likely to be based on our experience. Due to the number of reed buntings we have been recapturing from previous years (we have ringed 326 at the marsh since February 2013), we are now able to regularly truth our judgements through corss-referencing IPMR, and are becoming gradually more confident in our ageing of birds later into the winter.  We correctly identified three birds as adults and one as a first winter this morning, which was pleasing.

Sparrowhawk (Keith Vaughton)
The highlight of the day, however, was a male sparrowhawk. This bird has now been captured four times at the marsh. It was initially ringed as a juvenile male in August 2014, recaptured twice in the autumn of the same year, and is now in its third calendar year.

It is interesting to note the deeper, more orange-yellow iris that the bird has developed with age. The bird had some retained secondaries, lesser coverts and rump feathers, allowing it to be aged as a 7 (second winter  male).

Thanks to this morning's team of Paul Aubrey, Keith Vaughton and Emma Cole.

Further pictures of the sparrowhawk from when it was captured this morning and on initial capture in 2014 are below.

Owain Gabb
31/03/2016

Sparrowhawk (Keith Vaughton)

The same bird in 2014 (when juvenile)

Friday, 25 March 2016

Oxwich Marsh 25 March 2016: changing seasons

Settled weather allowed us to complete two sessions this week. The numbers of birds in the marsh remains modest, and the catches reflect this. It appears that the large flocks of finches present in January and February have now dispersed, while the first spring migrants are coming through.

The combined total from the two days is below:

Species
New
Recaptures
Total
Great Spotted Woodpecker
0
1
1
Wren
0
3
3
Dunnock
1
2
3
Robin
0
1
1
Chiffchaff
3
0
3
Goldcrest
1
0
1
Blue Tit
4
5
9
Great Tit
1
1
2
Chaffinch
2
1
3
Greenfinch
1
1
2
Goldfinch
10
2
12
Siskin
20
8
28
Reed Bunting
3
2
5
Total:
46
27
73

A view back towards the marsh from Oxwich Point. The marsh is tucked between the dunes and the woodland behind
The highlights have been good numbers of siskin (we have now exceeded the total of unique birds captured in 2015 and 2014) and a few spring chiffchaffs, some of which are carrying a little fat and one of which showed a pollen horn.  The numbers of greenfinches at the marsh appears considerably lower than in previous years: in March 2014 we captured 91, in March 2015 75 but in March 2016 only 5 birds.

The totals for the year to date (at the end of the first quarter) are as follows:

Unique Birds
Water Rail
1
Jack Snipe
5
Snipe
6
Great Spotted Woodpecker
4
Wren
10
Dunnock
13
Robin
7
Blackbird
3
Chiffchaff
6
Goldcrest
9
Long-tailed Tit
1
Coal Tit
4
Blue Tit
91
Great Tit
37
Treecreeper
1
Chaffinch
77
Greenfinch
32
Goldfinch
122
Siskin
89
Lesser Redpoll
1
Reed Bunting
33

Thanks to all who have made it along for the last couple of sessions: Keith Vaughton, Paul Aubrey, Wayne Morris, Dan Rouse, Val Wilson and Gareth Watkins.

Owain Gabb
25/03/2016

Saturday, 19 March 2016

Oxwich Marsh 19 March 2016: Gower Society grant funding .... and a water rail for good measure

This morning saw overcast skies and a light easterly wind.  We put up 480 feet of net: a 60 foot net by our bird feeders, a triangle of 40 foot nets to try to capture pipits and a complicated arrangement of five 60 foot nets to see if we could capture reed buntings, snipe and anything else that was using some rushy ground near to one of the main pools in the marsh.

The (modest) catch of 32 birds was as follows:

Species
New Birds
Recaptured
Total
Water Rail
1
0
1
Snipe
1
0
1
Wren
0
1
1
Dunnock
1
3
4
Robin
2
2
4
Chiffchaff
1
0
1
Goldcrest
2
0
2
Blue Tit
1
1
2
Great Tit
2
0
2
Chaffinch
1
0
1
Goldfinch
2
0
2
Siskin
4
2
6
Reed Bunting
4
1
5
Total:
22
10
32

Water rail (Owain Gabb)
The highlight of the morning was the first water rail captured on the Marsh since we began ringing in February 2013.  The bird showed a slate-grey throat, breast and underparts, a dark orange eye, and flesh brown tarsus. Based on these criteria we concluded it was in excess of one year old (Age 6 in ringing code). The length of the wing (113 mm) indicated it was a female.

Chiffchaff (Paul Aubrey)

Other highlights of the morning were the first chiffchaff of the spring (albeit we captured two birds in January so not the first of the year), and a common snipe. The latter may be the last we capture before they return in the autumn, as there are now few snipe left on the marsh. We only saw one other snipe this morning, which evaded the nets, and the settled weather may have led to a clear out overnight (as 4-5 birds were present yesterday).

There is either small-scale passage of reed buntings taking place at present or the breeding birds have returned to the marsh: possibly both apply, albeit there was no singing apparent. Whatever the explanation, this morning we saw more reed buntings (and also robins) than in recent weeks.  Although there was lots of singing among other species, the only birds we captured that were showing clear brood patches and cloacal protrusions were the dunnocks.

Finally, there seems to have been some turnover of siskins at the marsh, as while in recent weeks we have been capturing mainly ringed birds, today saw a reversal of this trend.

The best news of the morning was that we had secured grant funding from the Gower Society for the second year running.  This will go a long way to covering our costs and will enable us to keep up the effort of 2015. We are very grateful to the Society for their continued support.

Many thanks to those who made it out this week: Heather Coats, Paul Aubrey, Darren Hicks, Val Wilson, Dan Rouse and Hannah Meinertzhagen.  Thanks in particular to Darren for assisting with the set up of the nets we put up near the pool - an unsociable hours initiative.

Owain Gabb
19/03/2016

Oxwich Bay at dawn (Owain Gabb)