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Home , Great crested grebe, Podiceps, Tachybaptus

Notes -laying by the Great Crested Although the behaviour of Great Crested cristatus has been intensively studied, many questions are still open. One such question is how Great Crested Grebes lay their , and whether they exhibit any special behaviour during and after laying. The photographs on plate 63 show two stages in the laying process. This begins when the female sitting on the nest suddenly raises and then quivers the closed wings a little, without opening them. After one to two minutes this behaviour is replaced by treading move­ ments of the feet. Although the does not raise herself at all, these movements slowly push her on to the edge of the nest, and any eggs already laid become visible. When her cloaca is approximately above the nest hollow, rhythmic movements of the orifice indicate that the egg is coming, which then appears as a bright whitish-green patch in the widening cloaca. Slowly, almost hesitatingly, the egg is squeezed out (plate 63a); deposition occurs after more than half a minute of intensive pressing. Because part of the upper femur, as in all grebes, is developed in such a way that the legs protrude far back on the body, the cloaca is lifted so much when the bird is lying on the nest that the egg is ejected horizontally. Once the egg is laid, the female raises herself and beats her wings, only half open, for one to two minutes (plate 63b). After a further period of standing over the nest hollow, she slips into the water. She may resume incubation after she has jumped up on to the nest platform again, or she may leave this to the male; in the latter situation she accompanies him to the nest, as if to reassure herself that laying has been successful. From these observations it seems probable that the wing-beating of the ruficollis noted by H. Bandorf (1970, Der Zwergtaucher, p. 113) in similar circumstances was part of the normal behaviour following egg-laying; the author suggested that its function might be to dry out the wing , since it was raining heavily at the time. M. WIECHMANN Ingelheimerstrasse 24, 6 Frankfurt-am-Main j6, West Germany

Dr K. E. L. Simmons, whose paper on the breeding biology of the appears on pages 413-437, informs us that sequences showing the behaviour of the female after laying the egg are included in the film 'A Waterbird's World' made a number of years ago by C. K. Mylne for the Royal Society for the Protection of and that what seem to be similar 'wing-beating' movements

438 Motes 439 are sometimes performed by the relieved bird (apparently of either sex) at change-over during incubation. EDS.

'Foot-paddling' behaviour of Pied-billed Grebes In March and April 1972, in central Florida, USA, I spent many hours watching Pied-billed Grebes podiceps on lakes in and around Orlando and Winter Park. On four occasions I noted a form of'foot-paddling', in which the birds swam close to the bank where there was a narrow rim of emergent vegetation, and, while squatting in shallow water, made vigorous and alternate paddling movements with the feet. These stirred up sediment and dislodged small from crevices in the bank, which were avidly swallowed. Incidentally, it may be of interest that twice I noticed - eating while preening was taking place. The feathers in question appeared to be plucked from the flanks. BERNARD KING Gull Cry, g Park Road, Newlyn, Cornwall Purple Heron chick regurgitating young Little Grebe On 25th May 1970 I was ringing nestling Purple Herons Ardea purpurea in a colony near Las Nuevas in the Parque Nacional de Donana, south-west Spain. One of them regurgitated a dead half-grown Little Grebe Tachybaptus ruficollis immediately following handling. The grebe weighed 62 gm and had been swallowed whole. The heron was probably being fed exclusively by its parents, since it was still on the nest. Referring specifically to the Coto Donana colonies, Archives del Instituto de Aclimatacion (Almeria), 9:72, lists carp Carassius, eels (Apodes), Water Snakes Natrix maura, and larvae of dragonflies (Odonata) and beetles (Coleoptera) as recorded prey of the Purple Heron. The Handbook (3: 135) included young Great Crested Grebe Podiceps cristatus among recorded prey, but did not mention Little Grebe. The weights of eight full-grown Little Grebes mist-netted on the Goto Donana in 1970 were 135-185 gm (mean 159 gm). P. J. BELMAN wy Grange Road, London W5 3PH P. J. OIney comments that the Purple Heron, throughout its range, takes a wide variety of prey, though fish and (and their larvae) probably make up the majority of the food in most areas. Birds have been recorded before—see Birds of the Soviet Union (1966-68), vol. 2; Birds of West Central and Western (1970), i: 34 (which mentions 'young waterfowl'); Alauda, 7: 177-197; and Proc. Int. Orn. Congr., 9: 415-422, as well as The Handbook—but these are rarely identified and do not appear to form a significant part of the diet. EDS 440 Motes Common Sandpiper eating butterflies In the morning of 7th September 1973, on the Scrape at Minsmere bird reserve, Suffolk, I watched a Common Sandpiper Tringa hypoleucos catching butter­ flies. It ran a few steps into a clump of sea aster, emerging almost immediately with a butterfly in its bill. It then ran to the nearest pool of water, dunked the prey several times and swallowed it whole with remarkable ease. The bird did this three times in close succession. I also noted a repeat performance, possibly by the same bird, in the afternoon. On two occasions the butterfly was identified as a Small Tortoiseshell Aglais urticae; this was particularly numerous at the time. R. J. WATERS Royal Holloway College, Egham Hill, Egham, Surrey

Woodpigeons cooing while on the ground In 1941 I submitted a note, published in Brit. Birds, 34: 263, of a Woodpigeon Columba palumbus uttering the 'song' coo while on the ground. In his editorial comment, the late B. W. Tucker stated that, although the courtship coo may sometimes be given on the ground, he himself knew of no instance of the 'song' coo being so given, but that this had been mentioned by J. F. Naumann as of rare occurrence. A second instance was recorded by me in Brit. Birds, 50: 254. I now have a further record of this unusual behaviour in the Woodpigeon. On 16th April 1974, at Newcastle, Co Wicklow, a bird that had been feeding on my garden lawn stood up and 'sang' its full coo twice. Watching it from only ten metres, I noticed that the bill remained closed during cooing, the throat being puffed OUt. R. F. RUTTLEDGE Boon, Newcastle, Greystones, Co. Wicklow

Starling feeding lavender leaves to juvenile At 10.00 hours on 19th May 1974, in my garden at Brentry, Bristol, I saw an adult Starling Sturnus vulgaris pull off two leaves, each about 2 cm in length, from a bush of lavender Lavandula spica. The leaves were then fed to a newly flown juvenile which accompanied the adult. A. P. RADFORD 2 Wyck Beck Road, Brentry, Bristol BSIO 7JE

Starling feeding dandelion flower to juvenile In May 1973, on the lawn of my garden at Ipswich, Suffolk, I watched a parent Starling thrust a flower-head of dandelion Taraxacum officinale into a juvenile's mouth. After one ot two abortive attempts, the juvenile apparently swallowed the flower-head successfully. I did not see the parent pluck the flower-head off the plant. D. R. WARREN 103 Larchcrqft Road, Ipswich, Suffolk IPI 6PQ_ Notes 441 Dr Radford also writes that in his garden ten days earlier he had watched a male Blackbird Turdus merula eat two whole flowers and several individual petals of fallen apple blossom. Last year we published two notes on the use by birds, for food or nest material, of various common garden herbs and flowers (see Brit. Birds, 66: 231, 235). G. W. H. Davison, author of the second of these, adds that he has frequently seen Starlings sitting in a clump of male fern Dryopteris jilix-mas and pulling pieces of dead brown fronds from it, though for what purpose he has been unable to ascertain. There was also a report by P. Saltaire in the Daily Mirror of 13th June 1974 of Starlings carrying away beakfuls of leaves of sage Salvia officinalis from a large bush in his garden at Highcliffe, Hampshire, 'each year about the time the young hatch . . . , pre­ sumably to their nests'. EDS PLATE 63. Two stages in the egg-laying behaviour of the Great Crested Grebe Podiceps cristatus (photos: M. Wiechmann): above, the egg being slowly ejected (horizontally) from the cloaca; below, immediately after laying, the female standing up on the edge of the nest and beating her half-open wings (page 438)