Gloucestershire Naturalists' Society

Ashleworth CES Diary 2007 - Mervyn Greening

5 May

The CES year has begun, and the pre dawn meetings at the end of Dirty Lane are re-instated. Five o'clock this morning, and the weather was cold, overcast and with a light breeze. The breeze had dried the dew off the grass, so snorkelling gear was not required, but I’m sure that those of us who forgot their winter coats regretted it. All the equipment had been put in two weeks ago so all we had to do was yomp across the fields and put the nets up.

Catching was slow until the temperature rose a little just before the end of the session, and the largest catch was recorded in the final round. 36 birds caught of which 34 were processed. (2 were released un-ringed, due to their legs being covered in Knemadoptic mange - a chaffinch and a bullfinch.) This total puts the visit exactly on the 10 year mean of 34.1 (range = 21 – 48 with 1999 and 2005 being exceptionally high with 48 and 45, and 2006 and 2002 being the lowest with 21 and 26). The feeling is that there are more birds here than for the past couple of years, but the cold reduced the catch a little. Several Redstarts were singing, along with our Sedge warblers, and for the third year in succession Whitethroats are singing in the catching site. 11 species trapped is slightly higher than usual for the first visit, but this included singles of Great Spotted woodpecker, Treecreeper and Song Thrush, all of which are not regular.

Sedge Warbler numbers are up on 2006 with 15 different adults being handled so far (c.f. 9 by this time last year). This includes 8 on the pre-CES visit and 11 on this visit, with 4 being re-handled from a previous visit. (Are the birds back slightly earlier, or are there more birds on site? More birds were sexed on this visit than is usual, so perhaps the birds are breeding slightly earlier.) So far 7 new adults for the site have been ringed, and 8 birds from previous years have returned, 3 from ’06, 1 from ’05 3 from ’04, and 1 from ’03. Interestingly 2 of the birds from ’04 have not been re-trapped previously - both ringed as 3J juveniles in July, so were hatched on this site. The three birds from 2006 were first ringed as adults, again in July, suggesting that they were adults prospecting a new site, possibly having failed as breeders elsewhere. (See previous notes on this subject) The birds from ’05 and ’03 are well known to us. The ’03 bird (R294620) having been caught 6 times in ’03, 4 times in ’04, 4 in ’05 and 3 in ’06, and twice so far this year. It is very site faithful having been caught in the same net 16 times; it is also always one of the earliest birds to be caught. As a male, presumably it is a good idea to get back early and get a prime position in the site, which the area around net two seems to be. The 05 bird (T321447) on the other hand, has done something strange, and moved to the other end of the site, from where previously caught.

Capture list: Lesser Whitethroat (3,0), Reed Bunting (1,2), Dunnock (1,4), Whitethroat (1,0), Long-tailed Tit (2,1), Treecreeper (1,0), Bullfinch (1,1), Sedge Warbler (4,6), Chaffinch (2,0), Great Spotted Woodpecker (1,0), Song Thrush(1,0).

Species Observed: Grey Heron, Mute Swan, Canada Goose, Greylag Goose, Shelduck, Mallard, Lapwing, Lesser Black-backed Gull, Cuckoo, Green Woodpecker, Great spotted Woodpecker, Skylark, Swallow, Robin, Redstart, Song Thrush, Blackbird, Sedge Warbler, Lesser Whitethroat, Whitethroat, Chiffchaff, Willow Warbler, Long-tailed Tit, Chaffinch, Bullfinch, Carrion Crow, Wren, Treecreeper, Buzzard.

20 May

Our second CES visit of the year. Lucky to get a break in the weather. All the rain has made the grass grow, and it’s now up to our waists, with some patches higher. Carrying some new metal poles we made our way through the wet grass, and had the nets up by just after sunrise. It remained cool all morning, and catching was slow until the last round, when it warmed up a little, inducing a bit more activity.

The total catch of 25 was the second lowest for this visit, lowest was 17 in 2003. The ten year mean is 32.5. It was largely the lack of Sedge warblers that caused this drop. We expected more than the 8 we caught. There were plenty singing, but they didn’t move much today. The sedge warblers caught today means we have now trapped 18 different adults this year. This puts us two behind the equivalent visit last year, the small gap being due to the good catch last visit. We now have 10 birds returning from previous years.

Ten species were caught, the highlights being another Great Spotted Woodpecker, and a male Redstart. The cool conditions resulted in a reduced list of observed birds as well, but the view of a Kingfisher was cheering. A male Reed Bunting, bearing the colour rings orange over orange, was conspicuous by his antics near our table. He obviously has a nest close by.

26 May

CES 3 (4th visit of year). Close scrutiny of the weather forecasts, from Wednesday, had made me wonder whether or not we would get this visit into the programme. Last minute checking on Friday evening, and a change of plans for Saturday, led me to make hurried phone calls around the team. 04.35 at the end of dirty lane was the message.

Further growth of the grass and a heavy dew, meant the walk into the site was a damp one. The grass, in places, is now over shoulder high, and a combination of the denseness of the grass and it being flattened in places, by wind and rain, makes it a strenuous exercise to get to our base. However, cheered by blue sky and plenty of bird song, the nets were soon up. Again the low air temperature slowed catching and the first couple of rounds provided meagre pickings. From 07.00 things picked up a little, and we ended with a reasonable total of 36 birds caught, which is exactly on the ten year mean for visit three. (Double the number caught on visit three last year, but some way off the record of 54 caught in 2000.) Thirteen species handled was good (c.f. 8 last year), with Reed warbler making its first appearance of the year. The first juveniles of the year were caught today: Long tailed tits, a family party, a speckled Robin, and a less speckled Dunnock. The female Sedge warblers caught all had brood patches, and the stage of development of the patch showed them to be incubating eggs. Evidence that many local birds were incubating, was also provided in the form of Cuckoo activity. A couple of males were vocal all morning, and seen on several occasions, but more telling was the “bubbling” call of the female, heard twice, indicating two eggs laid this morning, so presumably two females active on the site.

The male Reed Bunting, orange over orange, was again conspicuous, but this time because of his industry. He was busy feeding young, carrying mouthfuls of insects to the nest. As previously anticipated, his nest site was not far away, and we could watch easily his visits. He wasn’t bothered by our presence, and was taking food in at intervals of about five minutes. We didn’t see the female feeding. Later in the morning when the grass was dry, we found the nest with 4 young in, a small circular nest of dry grass lined with brown hair. The young were three to four days old, naked and blind, with big yellow gapes. ( I returned to ring the young on Tuesday evening 29/05/07 to find they had grown to ringing size with some body feathers and wing feathers just in pin, but all dead. The rain of the last few days had finally taken its toll. This must be the outcome for many of the birds at present, because an hour’s observation on Tuesday evening, showed no feeding activity by any species in the site. The birds will have to start again when the weather clears up)

Our Sedge Warbler adult capture count is now up to 23, exactly the same as last year! (34 in 2005, 39 in 2004, 19 in 2003, 23 in 2002, 33 in 2000, 24 in 1999, 23 in 1998, fascinating!) There are now 12 adults from previous years on site. The last bird caught today was T321467, a male bird, that for the past two years has been the first bird caught, and was a very early arrival in 2006 and was one of the few successful breeders last year, getting a brood off early, before the hot dry weather led to many failed nests. He was faithful to a short stretch of hedge for 05 and 06, the most productive breeding area, but has now moved to the top of the site. Is this because he arrived back late, and the prime sites in the area of nets 2 to 4 had been taken? T020678 was ringed as a 3j juvenile, on 04/07/04, i.e. bred on site, and has not been caught again before today! T321550 is another well known bird, ringed as an adult early in 05, previously always caught on the edge of the prime area i.e. nets 4,5 and 6, he has now moved further in to the main area being caught in net 3. This number of returning adults already puts 2007 into joint 3rd place for returners.

Just before the end of the morning’s activities, a group of local residents, being led on a walk around the reserve by MS, arrived to see what we do. They were given a brief demonstration of ringing by MG. Birds seen and the full ringing list are on separate files.

3 June

The weather man has been too kind. The promised cloud didn’t materialise and we “enjoyed” windless conditions and a clear blue sky. Great weather for spectacular sunrises, with mist hovering over the grass, hedges just peering through, and web laden grass shining in the new sun, but less than perfect for catching.

The suicide squads of Blackbirds were joined by young rabbits, of which there seem to be large numbers, Magpies, and Woodpigeons today. To get to the rendezvous on time we had to get up at 3.45, nets due up by 0500. Unlike formula 1 drivers, who vie for pole position in a race, we prefer not to lead the way across the fields. Wet grass, now at head height in places, is best approached following someone else. Luckily John had new waterproof over trousers which he wanted to “break in”, more a full immersion baptism than baptism by fire. Even following the leader you get pretty wet. A larger than average team met the net challenge easily, and the routine of catching was soon in full swing.

The ten year average capture for this visit is 36, and we did well to get to 31. It was warm by 07.30 with damselflies on the wing. Following the deluge of bank holiday Monday, there was no feeding activity going on. Most of the young birds in nests must have succumbed. There was evidence of birds sitting on eggs, with a few females caught with brood patches in the condition for incubating. Whitethroats were still vocal, with a few Reed Buntings. A couple of new Adult Reed buntings were caught, leading to speculation that the breeding birds of last week, had given up following the deluge, and new birds had moved in. 3 new sedge warblers were caught and five retraps, bringing the total of adults caught so far to 27. Exactly the same as last year, and the number of returning adults is the same at 14!

With a large team, and small numbers of birds caught, there tends to be more time for conversation between rounds. This was the case today. A pleasant morning, topped off with the capture of an adult male Redstart.

17 June

Getting close to the summer solstice, and the earliest starts we have to make. Meeting at 04.35, meant a 03.50 alarm call for me. Following the rain of the previous week, it was lucky that we had a weather window in which to operate. Water was gushing into the reserve through the sluice gate, from a river swollen by the rains, with flooding upstream of us. Our Sand Martin colonies won’t have fared well, and it will probably be only the highest holes that will have survived. More immediately for us was the problem of getting across the fields. The rain had pushed a lot of the grass down, so pushing through it was impossible, instead each step of the way involved high stepping, which was extremely laborious. That and the wetness of the grass made for an uncomfortable trek into the ringing site, my face and hair were soaked by the time we reached the base. A super sunrise raised our spirits as we put the nets up. A reasonable number of birds were singing, but there didn’t seem to be much activity.

67 birds were caught during the morning, 56 newly ringed birds and 11 retraps. The bulk of these were Great tits (28 new and 2 retraps) 28 of which were juvenile birds of the year. 6 Redstarts were caught, 3 adults and 3 juveniles. This visit saw the first juveniles of migrant species. We have had resident bird juveniles for the last two visits, the first being a Dunnock on 28/5/07, but now our long distance travellers’ young are appearing. The first to be extracted from a net was a Whitethroat, closely followed by a redstart. Not surprising since both species have had several singing males on the site. Solitary Reed Bunting and Sedge warbler juveniles were also caught. The Reed Buntings must have suffered enormously from the rain, as they nest on the ground in the damper parts of the reserve. Redstarts won’t have suffered so much from the damp ground, as they use holes in trees. A notable juvenile was the Goldcrest that appeared in the last round, a second for the site in ten years. The visit total is well above the ten year average, but was heavily influenced by the Great Tits, and totals always vary at this time of year, depending on whether early young are caught or not.

Sedge Warbler numbers are pretty much the same as usual. We have now handled 28 different individuals, compared with 27 last year, 32 in 05, 43, in 04, 27 in 03. Thirteen of these are birds from previous years.

Although grass growth has been phenomenal this year, more brightly coloured flowering plants don’t seem to be so obvious. There are Flag Irises in flower, and the purple loosestrife is appearing, but there is not as much colour as usual. Several large patches of Dodder have appeared in dirty lane, looking like masses of tangled fishing line, entwining the nettles.

23 June

Just after the summer solstice, not that we saw the sun rise, it was too cloudy, but at least we can look forward to later starts. 04.20 this morning, and lucky to be out. The forecast showed a weather window, which I was happy to exploit. The preceding week has seen so much rain, that we had to wade through standing water in the first two fields. This is the first time we have had standing water in June. The stream at the sluice was high when we started, but the water was still, on our return at 11.00 water was pouring into the reserve again, and the trip back across the fields was harder as the water seemed a little deeper. As if all the tall wet grass was not enough, water underfoot has made the journey into the site a nightmare. The wetness has finally made an impression on MS who has given in and bought waterproof over trousers. For the first time we can remember, nets two, E1 and E2 had water beneath them!

Despite the conditions underfoot, the weather during the visit was perfect for mist netting. Warm, damp, overcast, with a little breeze, and the hedgerow vegetation surprisingly dry. We had the nets up quickly and were soon catching. The first two rounds yielded thirty birds each, and we finished with a good total of 93. The effect of young birds on the totals is shown by the fact that out of the total of 93, 66 were juveniles.

Although the weather has had a big effect on the Reed Buntings, we caught 6 juveniles. This is lower than what I would expect, but better than none which was what I was expecting. Despite being washed out twice, it appears that the reed Buntings, are trying again, a few males were singing, and we caught an adult female in egg. Sedge warblers appear to have been badly affected by the weather, Adult numbers are OK, but we are catching new adults, and fewer birds from previous years, which I think shows breeding failure and adults moving around to find new sites. One female was in egg, so she is either re-starting, or is just a late breeder. What is more telling is that we had no new juvenile sedge warblers, and re-trapped the juvenile from last week. This despite a good catch of juveniles for other species. Redstarts and Willow warblers have finished their breeding attempts as we have now had adults in post breeding moult.

Great Tits again had a big effect on the total, with 15 being caught, but good numbers were caught of most species (see totals chart). Two firsts for the year were caught today: Blackcap and Chiffchaff. A first for the site was also caught in the form of three juvenile Coal Tits. Cuckoos were still active, two males were heard, and two bubbling females were heard, so if they are still laying eggs, other species must be laying too. Further evidence of successful breeding by the Redstarts was provided in the form of two family groups being netted. One of these groups had very small young with only half grown tail feathers and flight feathers still in pin. All flying perfectly when released with dad in attendance, they are almost as vocal as long tailed Tits when in a family group.

The dodder in Dirty Lane is in flower now, with it’s little bunches of white flowers, adding extra colour to tangles of fishing line in the nettles. The first dragon fly of the year was flying – a female Common Darter, and several blue damsel flies were in evidence. The Small Tortoiseshell caterpillars, which have been munching the nettles, are now quite big, 2-3 cms long, and the crickets are growing, both in size and numbers. 3 butterfly species were seen: Red Admiral, Small Tortoiseshell, and Meadow Brown.

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