Monday, 26 May 2014

CES3 at WWT Llanelli

We thought we might have mixed fortunes with the weather this morning, the forecasters were all different so we really were not sure what to expect. Because we have other commitments with other CES and RAS in the week we decided to go for it. As it happened it was almost perfect, it was calm most of the morning, overcast until about 10.30 then the sun started to break out from behind the clouds.

The first three birds caught at 0630 were a re-trap Blue Tit and Robin and a new juvenile Blackbird.

The next round didn't produce a bird which was worrying then on round three we caught a Lesser Whitethroat. It was last years bird, a male and had a CP so hopefully it bred successfully.  It was also a new ringing tick for me. The last Lesser Whitethroat to be caught were 2 x Juveniles on 27/06/2011 and an adult on 31/05/2010. So this was a very special bird for us today.

On CES 3 last year we had a flock of Long Tailed Tits fly into the nets. The same happened today, catching a flock of 11 birds with another 2 about an hour later

Both pictures show a juvenile next to an adult. The juvenile being the bird with the brown coloured head. The weights of the Juv's varied from 7.2gms to 8.9gms less than out heaviest Wren today at 10.1gms. Such handsome birds.

The adult Blackcap was the only one we caught but there were many about singing in the trees. The Chiffchaffs were also singing away but they were not moving around.

Around the site there are pieces of roofing felt that have been placed to attract slow worms. Under one of these were two Common Shrews. They are one of Britain's smallest mammals. They have a massive appetite and can eat there own body weight of insects and worms every day. Shrews and other small rodents are the staple diet of Owls.

It was a good day today and by the end of the session we caught 34 birds compared with 18 for CES last Year It was also the highest number of birds since CES 3 in 2012. We are hoping the increased numbers are as a result of all the tree coppicing and trimming done by WWT in the winter to reduce the height of the trees surrounding our nets.

                                 2014 New                          Retrap                 2013New                Retrap
Blue Tit                       4                                   1
Robin                          1                                   2                             2
Blackbird                    2
Blackcap                                                          1                                                                1
Songthrush                 1                                                                  1
Lesser Whitethroat     1
Long Tailed Tit          12                                   1                             8                                 3
Great Tit                     1
Wren                           2                                   1                                                                1
Dunnock                     3                                   1

Totals                        27                                    7                           11                                5

Thanks to Heather Coats for coming along today.

Saturday, 24 May 2014

Oxwich Marsh 24 May 2014

A late change in the weather forecast allowed us to fit a session in this morning at Oxwich.  The rain held off until around 11:45, and an early moderate north-westerly breeze gradually lessened. 

The number of birds captured (45) was fairly typical of the last few sessions.  The breakdown was as follows:

Species New Re-trapped Total
Kingfisher 1 0 1
Dunnock 3 1 4
Robin 4 1 5
Blackbird 0 1 1
Sedge Warbler 1 0 1
Reed Warbler 1 0 1
Whitethroat 1 0 1
Willow Warbler 0 1 1
Blue Tit 1 0 1
Great Tit 2 1 3
Chaffinch 1 1 2
Greenfinch 9 4 13
Goldfinch 3 1 4
Siskin 0 6 6
Reed Bunting 1 0 1
Total: 27 17 45

The highlights were the second kingfisher of the year (a female), the first whitethroat captured in 2014 (a drab female that showed a well developed brood patch), a returning willow warbler (first captured in 2013), our first fledged greenfinches of the year and singles of both reed and sedge warbler.

The kingfisher was trapped over the bridge in the reedbed, and was sexed on the basis of the colour of the lower mandible.  In females two thirds of the lower mandible is orange, with the distal third (the third towards the head) being dark brown or black.

Female kingfisher

The reed bunting was an interesting bird, as it showed a lot of black around the head.  In the field, many birdwatchers might assume this bird was a male.  In the hand it was confirmed as a female, as it had a well developed brood patch, and a wing length towards the bottom end of the range shown by reed buntings (70mm).  A picture is opposite.
News had come in in the week of two birds that were controlled at the marsh earlier in the year.  The first, a siskin, was nice if unremarkable.  It had been ringed in Cradley, Herefordshire in March 2013, and was controlled (re-trapped) at Oxwich in March 2014.

The other control was of a dunnock.  This bird was ringed on 28 September 2009 in Creeting St Mary, Suffolk.  It was a first-winter bird when ringed, so fledged during the summer of 2009.  It was controlled at Oxwich on 1 March 2014.  During this time it had moved a distance of approximately 364km (approximately west).    As of 1 March 2014 it was therefore approximately in excess of 4.5 years of age. A nice, and unexpected ringing return for a common and widespread species.

A picture of the female whitethroat is opposite.  This was a very drab bird.  There does not appear to be territory immediately adjacent to the ringing rides this year, and as such early season captures have not occurred. 
Drinker moth caterpillar.

Many thanks to Charlie Sargent for help and company this morning.  Apologies for not letting everyone know about the session in advance, it was a very late call based on a change in the weather forecast.
Owain Gabb
24/05 /2014

Sunday, 18 May 2014

Oxwich Marsh and Margam Park 17 May 2014

Oxwich Marsh

A beautiful day at Oxwich.  Virtually windless for the first few hours, bright, sunny and warm.  While the weather conditions were very pleasant, they were not ideal for ringing however, as the nets became more visible in the sunshine.  This appears to have limited the catch, with only 39 birds trapped.  However, it did result in some good invertebrate activity, with numerous butterflies and dragonflies on the wing.  The catch was as follows:

Species New Re-trapped Total
Swallow 1 0 1
Wren 2 0 2
Robin 4 1 5
Blackbird 1 0 1
Sedge Warbler 2 0 2
Reed Warbler 3 0 3
Blackcap 1 0 1
Willow Warbler 1 2 3
Blue Tit 0 1 1
Chaffinch 1 0 1
Greenfinch 1 5 6
Goldfinch 1 3 4
Siskin 3 4 7
Reed Bunting 0 2 2
Total: 21 18 39
The only unexpected bird of the day was a swallow.  It was caught in a net in the reedbed that was close to, but not over, a channel.  The bird showed a cloacal protrusion (CP), so was a male.  However, we also measured the tail feathers, as these can be used to confirm sex in adult birds when this is not apparent from their breeding condition.  Adult males have a tail fork (the distance between the shortest and longest tail feathers) of >51mm, and females 35-58mm.  Total tail length in adult males is 93-132mm, and in females 76-112.  The total tail length of our birds (106mm) fell into the zone of overlap between sexes, but the tail fork was 60mm, suggesting a male (as confirmed by the CP).
Young birds were a feature of the catch, with the first juvenile chaffinch of the year being particularly welcome.  Juvenile siskins, robins and a blackbird were also noted.  There was also the first strong evidence of local breeding in goldfinch, as a female with a very clear brood patch (score 4) was noted.  The early trickle of reed and sedge warbler is good news, as August and September result in the largest captures of these species.

The 2014 totals for the site are as follows:

Species New Re-trapped Total
Kingfisher 1 0 1
Great Spotted Woodpecker 1 8 9
Swallow 1 0 1
Wren 7 11 18
Dunnock 6 16 22
Robin 6 9 15
Stonechat 2 0 2
Blackbird 3 0 3
Cetti's Warbler 2 3 5
Grasshopper Warbler 1 0 1
Sedge Warbler 6 0 6
Reed Warbler 6 2 8
Blackcap 10 0 10
Wood Warbler 1 0 1
Chiffchaff 8 0 8
Willow Warbler 9 4 13
Goldcrest 2 1 3
Coal Tit 2 0 2
Blue Tit 70 103 173
Great Tit 15 61 76
Magpie 1 0 1
Chaffinch 52 9 61
Greenfinch 155 37 192
Goldfinch 183 40 223
Siskin 59 46 105
Bullfinch 3 2 5
Reed Bunting 71 42 113
Total: 683 394 1077

Many thanks to Charlie Sargent and Keith Vaughton for their help and company this morning.  Some further photos of birds and other wildlife recorded are below

Owain Gabb

Sedge warbler

Small copper

Hairy dragonfly

Garden tiger caterpillar

Margam Park

Heather Coats, Chris Newberry and I were joined by Wayne Morris of the Cardiff Ringing Group. It was a warm, sunny morning with the only clouds in the sky rising from the nearby steelworks. We erected one hundred and two metres of net in three areas, one close to the pond and two along fence lines at opposite ends of the site.

Our total for the day was :
Species                  New            Retrap
Robin                        3                     1
Blackcap                   4
Chiffchaff                                         1
Willow Warbler         4
Blackbird                   3                     1
Wren                         1                     1
Dunnock                    1

A comparison of the tails of two Willow Warblers.

While on site we checked the nestboxes we had erected earlier in the year only to find that the only occupants were Common Wasps (Vespula vulgaris) the nest of one may be seen below.

Cedwyn Davies

Friday, 16 May 2014

CES2 at WWT Llanelli

It was CES 2 yesterday and we usually compare the results from each CES with the corresponding one from the previous year. This naturally gives us a quick indication of what is happening or not happening as the case may be.

At the start of the CES at 6.00am yesterday there was some cloud, there was no wind and we had almost near perfect conditions. Unfortunately the sun got up, and all but 2 of our nets were in full sun. They became easily visible and catch rates plummeted. By the end of the session we caught 24 birds compaired with 19 birds in 2013.

2014          New               Retrap                    2013                    New                Retrap

Dunnock      2                        1                       Dunnock                                       2
Blackbird     1                        3                       Blackbird                                       3
Backcap       1                        1                       Blackcap                                       2
Wren            2                        3                       Wren                    4                       1
Bullfinch      1                                                 Bullfinch                3
Jay               2                        1                       Long Tailed Tit                              1
Gtreat Tit      3                                                Chiffchaff                                       2
Blur Tit         3                                                Goldfinch               1

Total             15                       9                                                    8                      11

It was a disappointment that we only had two migrants the male and female Blackcap, however last year in the same period we only had 2 migrants, two retrap Chiffchaff's. We could hear and see a few Chiffchaff which stayed at the top of the trees, singing away. The numbers were an improvement on last year so this is two CES results where one way or another it has been a more productive day.

We all catch the odd Jay but yesterday we had 3 in the net and one of these was caught again later on.

It is not often you say the bird of the day was a Blackbird. The one above was a retrap and looking back in our records it was first ringed as a 5M on the 14/06/2006. It was therefore born in 2005 and this year it starts its 10th  year of life.

Thursday, 15 May 2014

RAS at Cwm Clydach

In a previous blog I talked about our Constant Effort Site (CES) at WWT Llanelli. A RAS is another programme initiated by the BTO and it means Retrapping Adults for Survival. Its aim is to catch or re-sight at least 50 birds of a predetermined single species during the breeding season. See link below for a full BTO description.

The species we have been targeting at Cwm Clydach is the Pied Flycatcher. Ringing Pied Flycatchers started way back in 1986 with 36 boxes. Today they have gone up to about 250 boxes which we monitor every Wednesday during the breeding season and record all the weekly results right up to the day of the last bird fledging. These results include any species of bird that uses the nest boxes. Besides the Pied Flycatchers we have Blue Tit, Great Tit and Nuthatch.

A few Pied Flycatcher facts from our data.

  • The peak number of Pied Flycatcher nests to the egg stage was 111 in 1997. 
  • Last year out of the 250 boxes we only got 21 nests to the egg stage which is an indicator of how productivity has become. This bird currently has an Amber status which reflects our concerns for this species. 
  • The oldest returning bird we have recorded was 8 years old. The oldest recorded Pied Flycatcher nationally was 9 years 0 months and 7 days. If our bird had returned last summer we may have held the record for the oldest bird recorded. Sadly it didn't, it may not have died and we are hoping that maybe this year it will turn up, however, realistically this is probably not going to happen. 
  • A Pied Flycatcher ringed as a nestling in 2008 was picked up in Liberia, West Africa, the first British ringed Pied Flycatcher to be found there.
  • Our site was registered as an official RAS in 1998 with the BTO.
The pictures below I took yesterday as I was checking all my boxes.

Last week there were only 4 Pied Flycatcher eggs in this nest which were cold and covered. This week the seven eggs shown were warm and uncovered suggesting incubation has started. Incubation is between 13-15 days and fledging 16-17 days

We have blue Tit boxes at various stages and incubation appears to have started in this box. Many of our other boxes have Pulli at various stages as well.

These Great Tit Pulli are only a day or so old. The nests in both the Tit boxes have been lined with sheep's wool.

Finally these Nuthatch Pulli will probably be Feather Small by next Wednesday and fledge the nest a week or so later.

RSPB Cwm Clydach is about 7 miles from Swansea