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Spoonbills have always proved difficult to see in the county and with only a handful of previous records, for many local birders this species has long been on their most wanted list. Surrounding counties such as Gloucestershire and Staffordshire often attract birds on a regular basis and this spring was no exception, while Warwickshire and West Midlands County also hosted a mobile individual. It was beginning to look as though Worcestershire would miss out again. However, all that changed on May 14th when a fine adult bird was discovered by Adam Holliday at Clifton Pits. It was roosting on the largest pit and although mobile at times, it lingered long enough for several local birders to connect. It later flew off south but then made a brief return visit the following day before again flying off south. Just two days later a Spoonbill was discovered by Rob Prudden at Bredon’s Hardwick and it was initially assumed to be the Clifton bird. However, it soon became apparent that this was a different bird, it’s black wing tips and lack of head plumes identified it as a first-summer individual. For those that had missed the Clifton bird, it was a great relief to get a second chance to finally see a Spoonbill in the county. The adult bird was never seen again, but the first-summer bird relocated a few miles to the south at Coombe Hill NR in Gloucestershire. It was an exceptional spring in Britain for Spoonbills with many birds being seen much further west than usual. In fact, Worcestershire birder Jason Kernohan was fortunate enough to discover one while on holiday in Pembrokeshire just before the Worcestershire occurrences. The previous Worcestershire records are as follows: One reported to have been shot near Malvern in the 18th century Two records of birds shot at Westwood Pool prior to 1850 One at Bittell in 1900 One at Grimley from September 1st to 9th 1984 One at Bittell on May 3rd 1986 One at Upton Warren on April 11th 1988 One at Bredon’s Hardwick on July 29th 1999 One over Wilden on June 4th 2000 One at Wilden on June 13th 2001
Adult Spoonbill at Clifton Pits. Photos: Oliver Wadsworth (left) and Andy Warr First-summer Spoonbill at Bredon's Hardwick. Photos: Andy Warr
Mock feeding in Starlings to gain close proximity for kleptoparasitism
by Trevor Jones
During the first few weeks of early May 2008 small flocks of Starling fed avidly on leatherjackets (Crane fly larvae) leapfrogging hedges and working from lawn to lawn in a Birmingham suburb. 15 - 20 birds would spend ten minutes or so foraging on each lawn with birds coming and rejoining the flock as others left with full beaks to feed hungry chicks not yet fledged. Their feeding technique for leatherjackets involved putting down previously caught prey to search for another. It was only because of the close proximity of the observations that the technique could be seen in detail. The fist peck would place the previously caught prey, up to three or four leatherjackets, down on the lawn the next peck would be deep and waggled, quickly followed by another peck to pick up the prey. The three pecks combined only lasting one second!
Occasionally a bird would be observed that didn’t feed as avidly but half-heartedly almost going through the motion of foraging. Foraging for prey often meant birds would concentrate searches at the base of larger tufts of grass or weeds growing in the lawn which seemed to be more successful.
Pirate birds did not focus their probing on these sites and also probed with shallow angled jabs not the deep straight strikes from determined feeders. The shallow angled jabs with inclined head seemed to be so that they could watch for the moment when the other bird put down its cache of prey to rush in and pinch leatherjackets placed on the ground. It was between the first and third peck that the pirate bird could snatch the leatherjackets. These tactics gave a closer proximity for pirate birds than if they just approached without feeding. Birds would quickly move away from individuals not feeding. Thus a group of frantically feeding birds would stay close together, 6 birds per m2, until a pirate revealed them selves by making an attack and then the flock would disperse more widely over the lawn. Whether it was the security felt foraging closely or a tendancy to congregate at productive spots, the flock soon came close together again when the pirate bird could be seen again making pseudo feeding movements with head tilted seemmingly waiting for the moment when a bird placed its prey on the lawn. This behaviour does not seem to have been described in Starlings before but similar problems have been reported in Oystercatchers. (Goss-Custard et al 1999).
Reference. Vigilance during food handling by Oystercatchers Haematopus ostralegus reduces the chances of losing prey to kleptoparasites JOHN D. GOSS-CUSTARD,, JOHN T. CAYFORD STEPHEN G. LEA Oystercatchers Haematopus ostralegus periodically pause while handling mussels Mytilus edulis to make visual scans. This paper presents evidence that scanning is associated with the high incidence of intra-specific food stealing among mussel-eating ... Ibis, Volume 141, Issue 3, Page 368-376, Jul 1999, doi: 10.1111/j.1474-919X.1999.tb04407.x
Oystercatchers usurp Lapwing nest
by Trevor Jones
At Upton Warren, Worcs during early May 2008 a pair of Lapwing (Vanellus vanellus) had started to nest on a raised pebble island which the previous year was occupied by Oystercatchers (Heamatopus ostralegus) Over a two day period numerous confrontations occurred between a newly arrived pair of Oystercatcher and the Lapwings. On 7th May an oystercatcher was sitting on a nest, apparently having won the territorial dispute with the Lapwings. The sitting bird was approached by its mate and stood up as if to swop brooding duties but the approaching bird stabbed an egg and flew off to an adjacent island with it. Seen clearly in flight through binoculars the egg appeared to have a dark brown background with almost black blotches to it, more like a Lapwing egg than the generally lighter ground of an Oystercatcher’s egg. If the egg was an Oystercatchers, then it would have to have been laid that morning as the previous day the pair were still harrassing the incumbent Lapwings. The egg was complete and not broken or just hatched. The Oystercatcher then proceeded to eat the contents of the egg in the shallow water at the edge of the adjacent island. The other bird retured to sitting on the nest, it was not possible to see if there were other eggs in the nest. No further repeats of this activity were seen. Could this activity where Oystercatchers have usurped an existing nest with eggs and then started to brood explain the records of different species chicks being raised by Oystercatchers. Triplet P. Sueru F. 1983. Avocet reared by oystercatchers Oiseau Fr. Rev. Ornithol. 53:251-260. Dougall T. 1996 Oystercatcher apparently rearing Lapwings. Obviously in this case the parent bird seemed to remove the Lapwing eggs. Usurpation of all nest types is less likely to occur in open areas (Lindell 95) The pair possibly used the same nest site the previous year but returned to find the Lapwings had starting brooding. Discussion around Oystercatchers competition for territories seems to focus on intraspecies confrontation and no mention of this type of behaviour has been found. (Goss-Custard J. 1996. Nethersole-Thompson D. 1988) The eating of the egg may indicate that this was the same pair of Oystercatchers that was seen eating Duck eggs in 2007 (Jones T. 2008)
References Dougall T. 1996 Oystercatcher apparently rearing Lapwings. Scottish Birds 18 :184 Goss-Custard J. Ed. 1996. The Oystercatcher: From individuals to populations. Oxford University Press. Jones T. 2008 Opportunistic egg predation by Oystercatchers. British Birds Feb 08 Lindell C. 1996 Patterns of nest usurpation. Harvard University Nethersole-Thompson D. 1988 The Oystercatcher. Shire Natural History Triplet P. Sueru F. 1983. Avocet reared by oystercatchers. Oiseau Fr. Rev. Ornithol. 53:251-260. Opportunistic egg predation by Oystercatchers On 6th March 2007 at Upton Warren nature reserve near Bromsgrove, Worcestershire a pair of Oystercatchers (Haematopus ostralegus) had been feeding with Curlew (Numenius arquata) on an adjacent field. They then flew on to the Flashes where a number of shingle covered island are dotted between two shallow pools. On one island two pale green duck eggs had been abandoned in the open, about a yard apart, completely exposed and unguarded. One of the Oystercatchers approached an egg and deliberately and without hesitating stabbed it and tried nibbling the contents. The second bird also tried to do the same but between them they managed to roll the egg into the water, where it sank but was still visible. They tried to get it back to the bank but only succeeded in pushing it deeper. They then turned their attentions to the other egg. The first bird again stabbed the egg and opened its beak forcing a larger hole. It started to eat the contents which could be seen to be fresh with an obvious yellow yolk. The Oystercatcher then picked up the egg using the broken opening and walked towards the waters edge as if to wash it, after the fashion when they catch worms. However the rest of the contents spilled out as both birds tried to eat in the shallows. This behaviour did not seem experimental but confident and determined with an appearance that it was not the first time they had encountered eggs as a potential food source. Oystercatchers have been recorded previously predating Gull (Larus) and Tern (Sterna) eggs and chicks (BWP) but certainly this is not common behaviour or something I have ever seen before. Trevor Jones Birds of the Western Paleartic (1983) Cramp, S. et al Vol 3 pg 22
The eastern-race Chiffchaffs at Kempsey On the morning of Saturday February 24th I arrived at Kempsey sewage works, in the hope of finally hearing one or both the pale eastern type Chiffchaff in song. Weather conditions seemed favourable for viewing Chiffchaffs, being relatively warm, with long sunny periods, but it was quite breezy. I soon heard my first singing Chiffchaff and spent the first hour or so locating singing birds and searching for colour ringed individuals. During this period I only observed collybita/western abietinus type birds, including two with colour rings (left leg - blue over blue and left leg - blue over green, both with orange/BTO rings on the right leg). Another collybita with colours blue over yellow on left leg and orange/BTO on right leg was also observed late morning.
At approximately 9.30am I finally heard a tristis type song coming from a hedgerow running north away from the sewage works. I quickly located this bird from the Kempsey Ham side of the hedge and observed it to be one of the pale individuals. I soon realised I needed to be on the other side of the hedge to obtain the best possible views of this bird and once this was achieved, superb views were had in good sunlight. This bird was observed for approximately one hour catching insects, as it moved through low Bramble and tall weed stems and was often noted flycatching from a wire fence alongside the hedge. Singing was heard on numerous occasions and the classic mournful peet call also heard at least five times.
This bird is considered the better candidate of the two pale individuals for being true tristis by other observers and myself and will be referred to as bird (A). The underparts were buff, particularly on the side of the breast and flanks, with the belly appearing more off-white. The supercilium was also buff and the ear-coverts a contrasting rusty/buff. No yellow could be detected on the face or underparts, but this can in some cases be impossible to confirm in the field. The crown, nape and majority of the mantle appeared uniform brownish/grey, with no obvious olive hue, but again olive may be present if viewed in the hand. An olive hue was noted on the closed wings, scapulars, upper tail, rump, back and possibly a limited amount on the lower mantle. The bill was small and dark, plus the legs and at least the top of the feet dark throughout. The second pale bird (bird B) showed alongside bird (A) very briefly and its general appearance was very similar, with the exception of being a little plainer on the upper and underparts, but I couldn’t be sure regarding the presents of yellow on the underparts. The feet on bird (B) also appeared paler than on (A). The song of bird (A) expressed no similarities to western Chiffchaff, being a soft, rising and falling sequence of notes, at times slightly reminiscent of Willow Warbler in structure. It was also interesting to note that the bill was only slightly opened when the song was delivered. By mid morning, bird (A) had moved to the hedge bordering the northern parameter of the sewage works. Looking up, with the sun behind the bird, its appearance seem a little different from the earlier views obtained. In particular I found it difficult to ascertain the extent of olive to the upper-parts, but I was still unable to detect any yellow on the face or underparts. By this point Brian Stretch had joined me in the hope of hearing the tristis song, but silence prevailed for the next hour or so. Eventually we did hear a bird sing predominately like tristis, but on two occasions, within a single song sequence, mix a single phrase of common Chiffchaff, ‘Chiff Chaff’, suggesting the song of an intergrade, but unfortunately this bird was hidden from view. This may have been bird (B), but we never managed to watch this bird sing or call so could not be certain of this. This mixed song was only heard once and thereafter only classic tristis song was heard.
It has been interesting to observe the change in appearance of these two paler birds over time. Both appeared whiter below, paler on the upper-parts, with olive restricted to the remiges when they first arrived at Kempsey in December. As the winter progressed both have developed more buffish underparts, become a darker brown on the crown, nape and mantle and an obvious olive hue was now present on the scapulars, back, rump and possibly the lower mantle. This must be due to the mid winter body moult.
To conclude, I can see no reason based on field observations and vocalization why bird (A) should not be a true tristis/fulvescens, but I still have not reached a firm conclusion on bird (B).
It is hoped another ringing session will take place here this weekend coming, weather permitting and that both birds may be trapped. If trapped feather samples will be taken for analysis. The ringing group is still waiting for the results from the third eastern type Chiffchaff ringed here in late December.
Andy Warr, February 28th 2007
The eastern-race Chiffchaffs at Kempsey As in past winters, a small number of Chiffchaff (Phylloscopus collybita) arrived at Kempsey sewage works, to take advantage of the wealth of insect life attracted to the filtration pans and consequently the surrounding trees and hedgerows. Three individuals appear to show characteristics suggesting them to be birds of eastern origin, i.e. birds that breed east of the Pechora basin and the Urals. These birds are assigned to the race tristis and commonly referred to as Siberian Chiffchaff. Birds on the western side of this range are referred to as ‘fulvescens’ and were once believed to be an intergrade population between true tristis and eastern abietinus. ‘fulvescens’ is distinguished from true tristis by the presence of slight yellow streaking on the eye-ring, the supercilium and the underparts, and sometimes a little more olive on the upperparts. It is not paler than tristis. Intergrades between tristis and abietinus can provide considerable problems and only birds which match the full suite of characters (plumage and vocal) should be identified as tristis. Also note that the yellow tones may be impossible to detect in the field. The most current thinking is that ‘fulvescens’ is now probably best regarded as a western form of tristis. Two of the three eastern types are very similar in appearance and I have described them below: Uniformed sandy brown upperparts, including the crown, scapulars and upper tail. Whitish underparts, with buff coloured flanks and side of the breast. The wings also appeared sandy brown and showed a slight green fringing to the edge of the primaries and secondaries, being paler on the latter, forming a slight wing panel. The ear coverts and the side of the throat showed a slight rusty/buff tinge, a little more obvious on one of the birds and the supercilium appeared buff. No traces of green on the upperparts or yellow on the face or underparts could be detected on either bird, but to confirm this, they would need to be examined in the hand. One bird showing pale tipping to the outer greater covert, forming a short wing bar and the second had a very narrow buff greater covert bar. Both had a small dark bill, with a pale cutting edge and dark legs. Hopefully both these birds will be trapped in the near future and the race confirmed. I heard one of these birds, not sure which, give the classic Siberian Chiffchaff ‘peet’ call. Apparently both tristis and ‘fulvescens’ call alike. The third eastern type was trapped, ringed and photographed on the 23rd December and was originally believed to be one of the birds mentioned above, but subsequent sighting of it in the field, revealed this bird to have darker upperparts and far more extensive buff underparts. In the hand it showed the following features: Supercilium, eye-ring, side of throat, side of neck, upper breast, under-tail coverts and flanks buff, plus further buff streaking on the lower breast and belly. Lemon yellow restricted to the axillaries and bend of the underwing. Ear coverts a uniform rusty/buff. Upperparts brown/buff, with olive flecking on the lower mantle, back, rump and scapulars. Upper mantle, nape and crown uniformed brown/buff. Olive fringing to the edges of the primaries, secondaries, tertials and tail feathers. Small dark bill, with pale areas to the cutting edge and a little at the base of the lower mandible. Legs black.
Adult eastern-race Chiffchaff trapped and colour ringed at Kempsey on 23rd December 2006. Colours are dark blue over pink on left leg, BTO ring and orange on right leg. The photo above shows clearly the contrast between the buff facial features and underparts, compared to the restricted lemon yellow on the underwing. This feature alone rules out ‘fulvescens’ as yellow would be present on the underparts and probably also the upper eye-ring and supercilium. The upperparts do appear more olive than would be ideal for tristis, but apparently a little on the lower mantle is acceptable and the presence of olive on the scapulars, back and rump is normal for tristis. The bill, though small as would be expected on tristis, does display a pale base, but this may possibly be acceptable on their western range. I have only heard this bird call once and it gave the classic tristis ‘peet’ note. When trapped, feather samples were taken and will be sent to be analysed. The results should tell us from where the bird originated. After consulting with Alan Dean, co-author of ‘Siberian Chiffchaff’ revisited, British Birds August 2005, it was suspected that this individual, at best, came from the extreme west of the distribution of tristis, though beyond the area occupied by ‘fulvescens’, as the bird appeared rather olive on the upperparts but devoid of yellow away from the underwing. After a more critical examination of various photographs, Alan was of the opinion that there was slight, if very limited, yellow streaking on parts of the underparts and that, in conjunction with the rather olive upperparts, this suggested an intergrade. The two paler, whiter bellied birds I suspect may fall into the ‘fulvescens’ category, or eastern abietinus/intergrade, but until trapped this remains to be seen. Andy Warr, December 2006
The Willow Tit at Grimley
In early November a feeding station was established by Roger Blackmore at Grimley old workings. With feeders positioned in front of the Island Pool Hide many Blue Tits and Great Tits soon took advantage of this new food source. On 17 November Terry Norledge noted that a Willow Tit was making regular visits to the feeders and it also became apparent that the bird wore a metal ring on it’s right leg. Over the following few days with patient observation it was possible to read some of the ring numbers and together with some excellent photographs taken by Oliver Wadsworth and correspondence with John Hodson the ring number was finally pieced together. It transpired that this individual was one of two Willow Tits that had been rung as juveniles at Grimley old workings on 20 July of this year. A single Willow Tit was also noted here in mid-August but was not seen well enough to notice any rings. There were no further signs until the ringed bird was noted on 17 November.
These close up images helped to piece together the ring number. This individual is the first Willow Tit ever to have a ring read in the field. The ring number is T079872 Willow Tits had formerly been an annual visitor to Grimley, particularly during the autumn but with no records since 2003 the series of records this year are all the more significant in that a pair may have bred in the area. Willow Tit is in decline nationally and in Worcestershire the species now appears almost absent south of Worcester. The species is still hanging on in the north of the county with Bittell Reservoirs, Clent Hills and the Wyre Forest being the most likely sites at which to encounter a bird. With thanks to Oliver Wadsworth, Mark Grantham at the British Trust for Ornithology and John Hodson, secretary of the Wychavon Ringing Group. Brian Stretch, December 2006 |
