Sunday, 31 July 2011

Bullfinch Bonanza at Botley Wood

An early morning ringing session on 29th July, did not produce the same number of birds as would be expected at Titchfield Haven, but the aim of the session was to try to catch any remaining Common Nightingales before they departed. Well, I failed on that count but still managed a total of 27 birds of 9 species. The species captured included 5 Robins, 2 Blackcaps, both juveniles, 3 Goldcrests, 2 Chiffchaff and a Nuthatch, but the most numerous was the Bullfinch, with 8 different birds captured. I have never had a ringing session where bullfinch was the most numerous species, and to make it even more interesting, the haul included a range of different ages and both sexes.

Male birds are stunning, with their bright pinkish-red underparts and their glossy black primaries, crown and tail. The mantle and back is ash grey, and the rump is white and is most obviously visible in flight.

Male Bullfinch

Females have the same glossy black primaries, crown and tail, but lack the pinkish-red underparts, instead they are brownish in colouration.

Female Bullfinch

Juveniles on the other hand lack the black crown, until they have undergone their post juvenile moult, which is usually completed by September/October.

Juvenile Bullfinch

The moult strategy for Bullfinch's is fairly straight forward, with adults undergoing a complete moult of all their feathers, whereas juveniles have a partial moult and therefore do not replace their wing and tail feathers. In the image below, all of the feathers are of the same generation, with no retained juvenile feathers visible.

Adult Bullfinch Wing

In the image below, a retained juvenile carpel covert and the alula covert can be seen to have a brownish fringe. I have inset a close up of these to feathers in the top right corner for ease of viewing. This bird would have been hatched in the summer of 2010, and is showing retained juvenile feathers, these will be moulted out following completion of its post nuptial moult in the next few months.

Second Calendar Year Bullfinch

The image below is a fully juvenile wing, prior to the start of its post juvenile moult. The brownish colouration to the tips of the greater coverts is clearly visible, in contrast to the greyish tone in the image above.

Juvenile Bullfinch

One of the male birds captured was a re-trap, which was originally captured on 6th June 2010 at the same site. This bird was originally aged as a second calendar year bird, which would have originally been hatched in the summer of 2009. 

All in all a good mornings ringing and I suspect that it will be a while before I catch 8 Bullfinch's in a single session again.

Wednesday, 27 July 2011

Bird Ringing - Titchfield Haven 26th July 2011

A pre-work ringing session on Tuesday 26th produced another 116 new birds, with the majority being Reed and Sedge Warblers. Amongst the Sedge Warblers was our second British control of the year, so we will look forward to news of that one. In addition to the Sedge and Reed's we also caught another 28 new Grasshopper Warblers, taking our total to 227 for the year, and once again they were all juveniles. An interesting range of colour morphs though, with at least half of them having bright yellow underparts.

Sylvia Warblers were also more evident than previously, with 4 Garden Warblers, 4 Common Whitethroats and 2 Blackcaps captured, along with 9 Willow Warblers. But the surprise was our first Reed Bunting of the year. We usually catch this species in the winter when they are attracted to the feeding stations, but this unsuspecting juvenile was obviously caught out by our nets.

Juvenile Reed Bunting

This individual still had the spotted head plumage of a juvenile bird, and unfortunately it had not moulted in its crown and head feathers so could not be sexed.

Juvenile Reed Bunting

Adults undergo a summer complete moult, and a partial late winter moult of the head and throat, whereas juveniles do not generally moult their wing and tails feathers, which subsequently become more worn through the winter.

Sunday, 24 July 2011

Bird Ringing, Titchfield Haven - 23rd and 24th July 2011

Two ringing sessions this weekend and a total of 326 birds captured. As with last weekend the most notable species was Grasshopper Warbler, 47 captured on Saturday and a further 25 on Sunday. So added to the 127 that we have already ringed during July, that is an unprecedented 199 birds before the end of July, and interestingly not a single adult bird. Hopefully that is a good sign and the adults are still nesting whilst the juveniles head south.

Other species captured included Garden Warblers, Common Whitethroats and Blackcaps in low numbers a handful of Eurasian Reed Warblers, and a marked increase in the numbers of Sedge and Willow Warblers. Sedge Warbler was the most numerous species captured on both days, and in contrast to the Grasshopper Warblers, included both adult and juvenile birds. Adult and juvenile Sedge Warblers undergo a complete moult on their wintering grounds and therefore can be aged very easily during the autumn migration. Juvenile birds have an olive-brown/straw ground colour to their plumage, with fine spotting on the sides of the breast, in addition there is a paler stripe through the centre of the crown.

Juvenile Sedge Warbler

Their plumage overall is very fresh, and this is usually very evident, particularly the wing tips and the tail feathers.

Fresh Plumage of Juvenile Sedge Warbler Wing

Adult birds have a generally darker brown colouration to the upper-parts, with pale almost white underparts, which lack any spotting, and a dark crown without any hint of a stripe. The plumage is generally very abraded, having been with the bird since the previous winter.

Adult Sedge Warbler

The tips of the wing and tail feathers are usually very worn, and this is usually very obvious, as in the picture below.

Worn Wing Feathers of Adult Sedge Warbler

The Sedge Warbler is one of the commonest birds that we ring and subsequently generates a good number of recoveries. Of the birds ringed last autumn we have had news of six foreign recoveries, four from France, one from Senegal and one from Mauretania. The four French birds were recaptured between nine and 22 days after the original capture date and had travelled between 304 and 401 kilometres to the south and east. The  birds captured in Senegal and Mauretania were captured 171 and 129 days later, 4054km and 4059km south-south west, respectively.

The peak month for Willow Warbler migration is August and so it was no surprise to see the numbers start to increase. Only two birds were captured on Saturday, but on Sunday we captured 9 birds.

Head of Juvenile Willow Warbler

Juvenile Willow Warblers have strongly and evenly, yellow coloured underparts and a bold yellow supercilium. Whereas adult birds tend to have generally white underparts that are streaked yellow.

Juvenile Willow Warbler

As we carried out our ringing activities this weekend, we were aware that we were being watched, and sure enough sat in the Willows by the ringing station was a female Eurasian Sparrowhawk. A pair of birds raised a brood here this year, and the female has taken to sitting by the ringing when she returns from hunting, even though the young have now left the nest. She was paying particular interest to recently released birds so we had to be very careful about where we released them, in order to ensure that she did not catch a bird just after we had just released it.

Female Eurasian Sparrowhawk

A couple of times she sat forward as if about to launch, but soon settled back into her resting position. We will have to keep an eye on her during the autumn.

Wednesday, 20 July 2011

Blue-cheeked Bee-eaters in Turkey - May 2011

With yet more wet and windy weather over the weekend there was unfortunately no opportunity for bird ringing, so I thought it was time to delve in the archives and another post from my Turkey trip in May 2011. This time, rather than post images of a selection of species, I thought I would focus on one species, and undoubtedly one of the trip favourites for many. Bee-eaters generally are popular species due to their bright and sometimes iridescent colouration, and the fact that they tend to nest in colonies, therefore can be seen in large numbers and are very approachable.

Blue-cheeked Bee-eaters - Turkey 2011

During this trip we encountered several, often large flocks of European Bee-eaters on migration, but it wasn't until our last full days birding that we saw Blue-cheeked Bee-eaters. And what a fantastic sight they were!

Blue-cheeked Bee-eater - Turkey 2011

We were taken to the outskirts of a small village called Ilhan Koyu, where there was a known mixed colony of European and Blue-cheeked Bee-eaters. The birds were nesting on a mound at the back of a farm, very close to the farm buildings, and were obviously used to human activity.

Blue-cheeked Bee-eater - Turkey 2011

There were only a few pairs of European Bee-eaters present, but at least 20 pairs of Blue-cheeked Bee-eaters. The Blue-cheeked's lack the bright yellow throat, red-brown crown and back and blue underparts, instead being predominantly green, with a red-brown throat patch and  smaller yellow chin.

Blue-cheeked Bee-eater - Turkey 2011

In flight both species have rusty-red under-wings, but the Blue-cheeked has an even width black trailing edge to the wing, and a longer and narrower tail projection.

Blue-cheeked Bee-eater - Turkey 2011

It was great to spend time photographing the two Bee-eaters species, and also listen to, and compare their calls, I will have to keep my ears tuned in for the the next time a Blue-cheeked Bee-eater flies overhead in Hampshire!

Blue-cheeked Bee-eaters - Turkey 2011

Friday, 15 July 2011

Grasshopper Warblers are on the Move

My first ringing session of the autumn at Titchfield Haven this week, and was somewhat surprised by the numbers of some of the birds we were catching. Our ringing site is set within an area of damp scrub, and adjacent to an area of grazed pasture, reedbed and the lower reaches of the River Meon. Typically, as you can probably image, it is a great site for warblers, in particular Reed and Sedge, but over the last few years it has also been an excellent site for catching large numbers of migrating Grasshopper Warblers. Our highest total for this species is over 550 birds in one autumn, with the earliest capture date being the 15th July. Well on Thursday 14th July, we caught just over 70 birds, of which 36 of them were Grasshopper Warblers, but even more surprising was that prior to this session 35 had already been captured that week. So in our first weeks trapping of the season we have captured over 70 Grasshopper Warblers already.

Juvenile Grasshopper Warbler

Grasshopper Warblers are a relatively easy species to identify having generally brownish upperparts, and variably coloured underparts which range from white to bright yellow. The crown, back and rump are faintly tipped white, and the under-tail coverts are diffusely streaked down the centre.

Grasshopper Warbler Under-tail Coverts 

Ageing Grasshopper Warblers in the autumn is very straight forward; juvenile birds have very fresh plumage, and the primaries are not worn or bleached............. 

Fresh Primaries of Juvenile Wing 

                               ...................whereas adult birds show varying amounts of old and new feathers, with the old features being very worn and bleached. 

Abraded Wing of Adult Bird

Adult Grasshopper Warblers undergo a partial summer moult, which is why they show both old and new feathers in the autumn. There does not seem to be a pattern to this moult strategy with feathers being replaced anywhere on the body and within the wings and tail.

Worn and Fresh Feathers of Adult Bird

Both adult and Juvenile birds undergo a complete moult on there wintering grounds, and therefore cannot be aged when they return in the spring.

Partial Albino Wing of Juvenile Grasshopper Warbler

The most interesting bird captured on the 14th July was a Grasshopper Warbler with the outer five primaries on each wing pure white. I have seen many partially albino birds over the years, but usually there are just a few random body feathers or a white head, and the most common species has been the Blackbird. Last year I captured a Song Thrush and a Blackcap that both had varying degrees of albino in their primary feathers, but I have never seen a Grasshopper Warbler with all white primaries like this.

Partial Albino Wing of Grasshopper Warbler

Friday, 8 July 2011

Tiger and Hawk Moths (and others) in Cornwall - July 2011

Another weekend in Cornwall, and with no chance of doing any bird ringing, and not much happening on the birding front, it was again time to get out the moth trap. It always makes the neighbours chuckle when I run the moth trap in Boscastle as it reminds them of a film that was partly filmed in the village, called Saving Grace, it was about a woman growing cannabis, and using lights that were very reminiscent to my moth trap...worth a look if you get a chance. Obviously I am only interested in the moths!

We were in Cornwall for two nights, and the weather looked good, so I thought I would try both nights, and was rewarded with 38 and 40 species, respectively. Most of the species caught were run-of-the-mill species that I normally catch at home, such as Heart and Dart, Dark Arches and Spectacle, but included a few more unusual species for me such as Grey Arches, Plain Golden Y and True Lover's Knot.

Spectacle, Boscastle - July 2011

The haul included colourful individuals such as Garden Tiger, a species which can be very abundant, but I have only ever caught five in one night. The adult moth has one generation, flying in July and August; they fly late at night and are readily attracted to light.

Garden Tiger Moth, Boscastle - July 2011

Three species of Hawkmoth were also in the trap, Eyed, Poplar and Elephant. All three species are common but the pink and olive green Elephant Hawkmoth is the most distinctive. The adults have a long flight season which extends from May through to early August. The pupae are most often found on Great or Rosebay Willowherb.

Elephant Hawkmoth, Boscastle - July 2011

Two species that I had only previously encountered once before, were Broad-barred White and Marbled Coronet. Broad-barred White is a resident species which usually inhabits vegetated coastal dunes, shingle and disturbed rough grassland, so not really sure what its doing on the cliffs in northern Cornwall.

Broad-barred White, Boscastle - July 2011

Marbled Coronet is classified as a Local species of open grassland on calcareous soils, especially on the coast. The species flies from May through to early July, and in total I captured three over the two nights, so obviously a more common species in Boscastle than in my Hampshire garden, where I have caught just one in 12 years.

Marbled Coronet, Boscastle - July 2011

Another species captured was the Drinker moth, with two caught on the second night. The female, pictured below, is larger than the male and is usually coloured deep yellow through to very pale buff. Males are usually warm reddish brown in colouration, with yellowish patches, but the species is variable.

Drinker Moth , Boscastle - July 2011

Surprisingly, the majority of the moths captured were larger macro moths, although some micro species were captured. Celypha striana and Chrysoteuchia culmella were relatively abundant with double figures captured and a single Diamond-back Moth was in the trap. But another micro species and one that I don't see very often was Udea prunalis. This is a common species that is normally associated with blackthorn, with the larvae feeding on the leaves of Woundwort, Dog's Mercury and Honeysuckle.

Udea prunalis, Boscastle - July 2011

Not all of the moth species encountered over the weekend were in the moth trap, a stroll around the cliffs produced several Scarlet Tigers. A copulating pair of moths was located in the cliff top grassland. This is another species which is classified as having a Local distribution and is associated with marshy ground, river banks and water meadows.

Scarlet Tiger, Boscastle - July 2011

Most of the moths encountered were high up on the cliff tops and not in the river valley, which is apparently their preferred habitat. The food plant of the larvae is Comfrey, Nettle, Bramble and Meadowsweet.

Scarlet Tiger, Boscastle - July 2011

Other selected species recorded included Buff Arches, Lackey, Purple Clay, Cabbage Moth, Ingrailed Clay, Purple Bar, Sharp-angled Peacock and Dot Moth.

Sunday, 3 July 2011

Bird Ringing in Mid - Late June 2011

Not much to report on the bird ringing front in the latter half of June, but a session on the Leckford Estate in Hampshire was interesting. The bird ringing session was part of an educational wildlife day that included moth trapping, plant and invertebrate identification. I was doing the bird ringing demonstration, along with two helpers, to over 50 eager visitors. I did the same event last year and only managed to catch 11 birds, but the number was not important as I caught a juvenile Common Kingfisher, so I was invited back again to see if I could repeat the feat.

The visitors were not due to arrive at the ringing area until around 10:30 and would remain until around 14:30, but we had to arrive early in order to cut in net rides and put the nets up. In terms of the number of birds and the mix of species, the day surpassed the previous years total with 37 birds captured of 14 species, Blackcap, Great, Blue, Marsh and Long-tailed Tits, Robin and Eurasian Treecreeper were all on the list.

Eurasian Treecreeper, Hampshire June 2011

The Eurasian Treecreeper was a juvenile bird, which had yet to undergo its post-juvenile moult. Both adult and juvenile birds undergo a complete moult and therefore cannot be aged, once they have completed it. 

Head of Eurasian Treecreeper June 2011

During the session two European Reed Warblers and nine Sedge Warblers were also captured. Five of the Sedge Warblers were recently  fledged birds and had not even fully grown their wing feathers, but the most interesting bird of the nine was the adult male that I had captured the previous year. Other species included a pair of Eurasian Bullfinch's and a couple of Chiffchaff, but once again it was the juvenile Common Kingfisher that stole the show.

Common Kingfisher, Hampshire - June 2011

Most peoples view of a Common Kingfisher is a turquoise flash as one quickly flies off down a river or stream, so you can image the response to seeing one in the hand. Adult birds can be sexed by the presence of red at the base of the lower mandible, in females and an all dark lower mandible in males, although this feature is generally unreliable in juveniles.

Common Kingfisher, Hamphire  - June 2011

I think overall the day was again a success, and everybody certainly enjoyed the Kingfisher, hopefully I will be invited back next year, but will I be able to catch another?

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