Monday, 31 August 2015

Oxwich Marsh 29-30 August 2015: a pair of number two's.............

A blustery Saturday, followed by a calm, cloudy Sunday.  

The Saturday was the main session due to people's availability.  We erected 500 feet of net in scrub (200 feet) and along a dry bund through reedbed with patches of ruderal vegetation and stands of bracken (300 feet).

I did a short (2 hour) supplementary session on the Sunday, as the forecast was perfect for catching birds, with very low wind speed and dull, overcast conditions.  The net was limited to 300 feet on the bund. 

It appears likely, based on the results from Sunday (25 birds) that a lot of birds moved on during Saturday night.

The combined total for the two days is below

Species New Re-trapped        Total
Tree Pipit 1 0 1
Wren 2 1 3
Robin 3 0 3
Blackbird 1 0 1
Cetti's Warbler 1 0 1
Grasshopper Warbler 2 0 2
Sedge Warbler 12 1 13
Reed Warbler 19 1 20
Whitethroat 1 1 2
Blackcap 5 0 5
Chiffchaff 3 1 4
Willow Warbler 5 0 5
Blue Tit 2 3 5
Great Tit 0 1 1
Nuthatch 1 0 1
Chaffinch 1 1 2
Reed Bunting 3 0 3
Total: 62 10 72

The highlights of the catch were the second tree pipit of the year, the second nuthatch of the year (and since ringing at the marsh recommenced at Oxwich in February 2013) and grasshopper warblers nine and ten of 2015.  It was also good to catch a reasonable number of reed warblers.

At least 6 tree pipits were heard over the morning, and one was captured and one escaped from a net on approach on the Sunday.  A good still morning with plenty of net and personnel at present might see us catch a few birds.  The individual captured was a first winter, and showed pale fringes to the tertials and a mixture of adult and juvenile feathers in the coverts. The nuthatch was a female, but was not aged due to the fact that following post juvenile moult no differences between adult and first winter birds are currently known.  It was sexed based on the relatively dull colouration of the undertail coverts and flanks.

The grasshopper warblers were a first winter and an adult.  The fresh plumage of the juvenile contrasted markedly to the heavily worn wing and tail feathers of the adult bird.

Many of the warblers were carrying significant fat indicating active migration.  Two of the sedge warblers had a fat score of seven, where only a small amount of the breast muscle remains visible and much of the remainder of the bird is covered in fat.  The heaviest sedge warbler on the weekend was 18.2g, which was approximately 7g more than the lightest.

Nuthatch (female)

Tree pipit (with ticks around the bill and above the eye)
Thanks to the Saturday team of Darren Hicks, Wayne Morris and Cedwyn Davies.

Owain Gabb
31/08/2015

Sunday, 30 August 2015

A Surprise for CES 12 at WWT



When a CES project has been going for 14 years, the ringers have a good idea about what species will turn up in the nets. Therefore it was a surprise to have a juvenile male Green woodpecker for CES 12 on Saturday 30th August! We had heard them on previous sessions but didn't expect to catch one. More predictable were adult Chiff chaffs in wing moult, getting ready for their migration to North Africa. Although numbers were low, the ratio of adults to young birds (5/12) continue to show that it has been a good breeding season.


SPECIES
NEW
RETRAP
TOTAL
Blackcap
2

2
Blackbird

1
1
Blue tit

1
1
Bullfinch

1
1
Cetti's warbler
1

1
Chiff chaff
3

3
Dunnock

1
1
Green woodpecker
1

1
Robin

1
1
Treecreeper
1

1
Wren

4
4
Total
8
9
17


The Cetti's warbler was the sixth new bird of this species for this year and the fourth juvenile.
 We watched dragonflies between net rounds.

Cetti's Warbler

Chiffchaff

Migrant Hawker

Thanks to Paul Aubrey for his assistance, company and photographs.


                                                                                                                 Heather Coats

Monday, 24 August 2015

Oxwich Marsh 23 August 2015: first swallow roost of the year

Another unsettled period of weather drew to a close yesterday.  However three days of heavy rain left its mark in the marsh, with water levels in the rides higher than at any time during the preceding winter.  

Despite this, however, we put out nets in the fen meadow to catch roosting swallows, and an additional (optimistic) three nets on a raised earth bund to see what was moving between the bracken on either side.  We only left these latter nets up for about an hour.

Sunset was around 20:20, but the swallows didn't come in until almost an hour later, and the flock took a long time to build.  The house martins that had been so numerous in the area when we arrived at 18:00 had long disappeared, but as usual there were a few sand martins mixed in.

The catch was as follows:

Species New Re-trapped Total
Sand Martin 4 0 4
Swallow 86 0 86
Wren 0 1 1
Sedge Warbler 1 1 2
Reed Warbler 4 1 5
Whitethroat 1 1 2
Blackcap 0 1 1
Blue Tit 0 3 3
Great Tit 0 1 1
Total: 96 9 105

Of 86 swallows captured, 15 were adults.  A few swallows came in early, and we took full biometrics on them, but after dark we only recorded detailed information from the adults (age, wing length, total tail, tail fork and weight).    The swallow flock was not as large as at this time last year, when the equivalent session resulted in 128 swallows and one sand martin being captured.  The sand martins are always a pleasant bonus: we had one adult and three juveniles during this session.  All the late swallows and the sand martins were over-nighted in purpose built boxes, and released at dawn the following day.

A second bonus was that the bund nets paid off with a little bit of warbler action.  Nothing unexpected, but enough to keep things interesting, with four new reed warblers alone making the effort worthwhile.  However, all silver linings have their cloud, and the capture of no fewer than six dor beetles and a common pipistrelle (which was duly extracted by a gloved Paul) along with the swallows provided it.  The beetles are very difficult to extract and frequently get very tangled.

A team tonight of Phil Mead, Heather Coats, Darren Hicks, Wayne Morris, Paul Aubrey and Keith Vaughton made the session go very smoothly.

Some pictures taken by Paul are below.

Owain Gabb
24/08/2015


L-R: Phil, Darren and Wayne, with Keith in the foreground

Taking a swallow wing length
One of the 72 young swallows ringed last night

Thursday, 20 August 2015

Less birds allows more time for scoring.

CES 11 at WWT Llanelli

           The weather was good for ringing on Monday - overcast and calm - however we had the smallest catch this season at 23 birds. The total for the year is still up on last year. Once again we had more juvenile birds (18) than adults (5) but not so many of the migrant species as last session.

SPECIES
NEW
RETRAP
TOTAL
Song thrush
1

1
Robin

2
2
Dunnock
1

1
Great tit
3
2
5
Blue tit
1

1
Long-tailed tit
2

2
Wren
1
1
2
Blackcap
2
1
3
Chiff chaff
4

4
Bullfinch
1
1
2
Total
16
7
23

                     There was time to look closely at wing moult and practice moult scores!
                     
              My thanks to Paul Aubrey, Phil Mead and Dan Rouse for company and assistance.


                                                                                       Heather Coats

Tuesday, 18 August 2015

Oxwich Marsh 18 August 2015: chats, warblers and a pipit

An extra session to make the most of the settled weather (until today anyway) proved a good decision.  Although the catch was modest, probably reflecting the fact that birds have no current reason to stop off at the site when the conditions are so good for migration, we had some real quality. The breakdown was as follows:

Species New Re-trapped Total
Kingfisher 1 0 1
Tree Pipit 1 0 1
Wren 3 0 3
Dunnock 0 2 2
Whinchat 1 0 1
Stonechat 1 0 1
Cetti's Warbler 1 1 2
Grasshopper Warbler 1 0 1
Sedge Warbler 5 2 7
Reed Warbler 9 0 9
Whitethroat 6 1 7
Blackcap 2 3 5
Chiffchaff 2 0 2
Willow Warbler 6 0 6
Blue Tit 6 6 12
Great Tit 0 7 7
Greenfinch 5 2 7
Siskin 1 0 1
Bullfinch 2 0 2
Reed Bunting 1 2 3
Total: 54 26 80

The highlights were the first whinchat for the site, a juvenile bird, the eighth unique grasshopper warbler of 2015, a young stonechat, and the first tree pipit of the year.  The eighteenth unique Cetti's warbler of 2015 was a bonus - it was a bird in entirely juvenile plumage.

Only a short write up, as it is difficult to fit everything in on a week day!

Thanks to the team today: Heather Coats, Dan Rouse, Keith Vaughton, Paul Aubrey and Mike Shewring (who joined us for the first time).

Some pictures of the birds are below.

Owain Gabb
18/08/2015

Tree pipit. This shot shows the short, stout bill (in comparison to meadow pipit) well (Pic: Paul Aubrey).

Male siskin.  This bird was well advanced in its post juvenile moult, and was replacing its central and outer tail feathers for good measure (Pic: Paul Aubrey).

A young whinchat.  Always nice when something unexpected turns up - albeit we did run a net through some warm bracken patches with a view to catching stonechats (pic: Keith Vaughton)

Whinchat (Keith Vaughton)

Whinchat (Keith Vaughton)

Sunday, 16 August 2015

Oxwich Marsh 15 August 2015: an autumn redstart

A predominantly bright day, with a gradually strengthening westerly wind.  In addition to 560 feet of standard nets in a mixture of scrub, reed bed and ruderal (with scattered scrub) habitats, we also put a series of two-shelf nets along an earth bund through an area of dry reedbed with stands of bracken and scattered rosebay willowherb.  The latter proved very successful, as the bund separated two areas of similar habitat, and birds regularly moved across it: it was also relatively exposed, and the birds were moving below the height of the marginal vegetation.

The catch was as follows:

Species New Re-trapped Total
Great Spotted Woodpecker 0 3 3
Wren 3 0 3
Dunnock 1 2 3
Robin 1 3 4
Redstart 1 0 1
Blackbird 0 2 2
Cetti's Warbler 0 3 3
Grasshopper Warbler 2 0 2
Sedge Warbler 12 1 13
Reed Warbler 8 1 9
Whitethroat 5 0 5
Blackcap 1 1 2
Willow Warbler 6 0 6
Blue Tit 13 8 21
Great Tit 1 5 6
Chaffinch 1 2 3
Greenfinch 23 3 26
Siskin 0 1 1
Reed Bunting 0 1 1
Total: 78 36 114

The features of the catch were:
  • A female common redstart, the first of this species to be captured at the marsh since ringing recommenced in February 2013;
  • The sixth and seventh grasshopper warblers of the year, both of which were young birds undergoing post juvenile moult;
  • A good day for whitethroats, with five young birds captured;
  • A steady catch of reed and sedge warblers.  We are awaiting a real fall of both species - and are behind the game with regard to sedge warbler in comparison with 2014;
  • The continued good catches of greenfinches.  All were juveniles, with some not having started their post juvenile moult.  All appeared healthy, with no evidence of trichomonosis at present, which is good news.
  • The lack of blackcaps.  A week ago 240 feet of net returned 23 blackcaps.  This week, more than twice the amount of net returned only two birds.  
Ageing of female common redstarts is difficult, as adults undergo a complete summer moult and young birds a partial post juvenile moult.  It follows that both adults and juveniles of both sexes have fresh plumage in the autumn (albeit juveniles may show a little more wear to the primaries and tail feathers and a moult limit in the greater coverts).  In males, clear moult limits in the greater coverts in 1st winter birds, the extent and purity of the white tipping on the throat feathers and of the white band above the eyes can all be used to determine age,

Photographs are below.

A first winter lesser whitethroat from earlier in the week.  Aged on the basis of the uniform olive colour of the iris and the pattern of the 5th tail feather (Owain Gabb)

A female redstart.  Tentatively aged as a first winter. (Keith Vaughton)

Female common redstart (Keith Vaughton)

Great spotted woodpecker.  The darker red coming through on the hind crown indicates this is a male (the juvenile red feathering on the rest of the crown is being moulted out).


Thanks to Val Wilson, Heather Coats, Wayne Morris, Cedwyn Davies and Keith Vaughton for company and assistance on Saturday.

Particular thanks to Val for scribing and to Cedwyn for taking the initiative to set the two-shelf nets. The redstart, grasshopper warblers and all but one of the whitethroats came from them.

More information on trichomonosis can be found here:
http://www.bto.org/volunteer-surveys/gbw/gardens-wildlife/garden-birds/disease/trichomonosis

Owain Gabb
15/08/2015