381© British Birds 100 • June 2007 • 381–383

In spring 2006, at a site in central England, aSlavonian Grebe Podiceps auritus paired with aGreat Crested Grebe P. cristatus, laid eggs, andproduced two young, which unfortunately didnot survive. The Slavonian Grebe had arrived atthe site, a disused clay-pit approximately 0.6 hain extent, on 29th April and, about two weekslater, a Great Crested Grebe appeared too.Breeding Little Grebes were already presentwhen the Slavonian Grebe arrived, but noattempt to pair with them was observed. On10th June, the Slavonian and Great CrestedGrebes were photographed displaying together(plate 154). During the following week or sothey built a nest at the edge of a small reedbed.On 25th June, one egg was seen in the nest; on6th July, four eggs were visible during a change-over of incubation duties (which were shared bythe two birds); and on 23rd July, one smallchick was seen by the nest (plate 155). A secondchick hatched on 25th July, but sadly bothchicks were predated by a Great CormorantPhalacrocorax carbo the following day. Thegrebes continued to incubate the remainingeggs, but these did not hatch. Both birdsremained at the site until 6th November.

Although Slavonian Grebe has been reportedbreeding with Black-necked Grebe P. nigricollis in

Scotland (Dennis 1973), this appears to be thefirst documented interbreeding of Slavonian andGreat Crested Grebe, and the first breedingattempt by a Slavonian Grebe in England (seeBrown & Grice 2005). In mainland westernEurope, small numbers of Slavonian Grebesbreed in Germany but otherwise there is no pop-ulation south or west of Scandinavia (Hagemeijer& Blair 1997). The Scottish breeding populationlies well to the north of central England and in2006 numbered only 39 pairs (S. Benn pers.comm.). Fjeldså (2004) stated that hybridisationin grebes is rare, but also that late-season hybridi-sation may be a result of active and adaptive matechoice by individuals with limited alternatives,rather than of species misidentification.

Acknowledgments

I thank Stuart Benn (RSPB) and Ian Francis (RBBP) forcomments, and the local County Recorder for additionalcomments.

References

Brown,A., & Grice, P. 2005. Birds in England. ChristopherHelm.

Dennis, R. H. 1973. Possible interbreeding of SlavonianGrebe and Black-necked Grebe in Scotland. Scott. Birds7: 307–308.

Fjeldså, J. 2004. The Grebes. OUP, Oxford.Hagemeijer,W. J. M., & Blair, M. J. (eds.) 1997. The EBCC

Atlas of European Breeding Birds. Poyser, London.

NotesAll Notes submitted to British Birds are subject to independent review, either by the Notes Panel or

by the BB Editorial Board.Those considered appropriate for BB will be published either here or on our website (www.britishbirds.co.uk) subject to the availability of space.

Slavonian Grebe breeding with Great Crested Grebe

Stephen J. Toonc/o Rare Breeding Birds Panel, The Old Orchard, Grange Road, North Berwick, East Lothian EH39 4QT

154 & 155. Slavonian Podiceps auritus and Great Crested Grebes P. cristatus, with hybrid chick in plate 155 (right),central England, June–July 2006.

Step

hen

Toon

Step

hen

Toon

382 British Birds 100 • June 2007 • 381–383

In May 2006, nearBunessan in the southwestpart of Mull, Argyll, mydaughter and I spotted aPuffin Fratercula arctica‘floundering ashore’through the surf. It soonbecame apparent that itwas ‘unwell’ and behavingabnormally. A closerinvestigation revealed thatthe bird’s head was a massof ticks, and the accompa-nying photograph wastaken. We placed it higherup the beach, in the coverof large boulders, where itmade a determined effortto seek shelter. Later thatday we looked for it againbut could not find it.

Notes

Puffin with exceptionally heavy tick infestation

156. Puffin Fratercula arctica infested with ticks, Mull,Argyll, May 2006.

Dav

id P

layle

David Playle39 Whitehouse Road, Claverham, Bristol BS49 4LJ

EDITORIAL COMMENT Mike Harris commented as follows: ‘Although it is impossible to be surewithout examining specimens, the ticks appear to be engorged Ixodes uriae, a common species thatparasitises a wide range of seabirds in both the northern and the southern hemisphere. In Britain, thecommonest hosts are Common Guillemot Uria aalge and Kittiwake Rissa tridactyla. This tick has threelife stages: larva, nymph and adult. All stages, except adult male, engorge with blood during a singleattachment to the avian host that lasts 4–8 days. The larger, older stages tend to be found on the headand neck, where birds cannot preen. Perhaps surprising, there is nothing to suggest that this Puffin hasattempted to scratch the ticks off. After feeding, the tick detaches, enters the soil or a crack in the rocksand either moults to the next stage before overwintering and feeding again the next year, or in the caseof the adult female, searches out a male, is fertilised, lays eggs and dies. The life-cycle typically laststhree years.

‘This Puffin has a deep, well-rounded beak with at least two well-developed grooves on the uppermandible. This suggests that it is at least 4–5 years old and, given that the observation was made inMay, will probably have been incubating, likely on the nearby Treshnish Isles. Typically, Puffins pick upticks within the nesting burrow at this time of year. Our work on the Isle of May suggests that the inci-dence is low (c. 10%) and, since the numbers of ticks involved are usually small, and all but engorgedfemales are easily overlooked, even when the bird is in the hand, it is only rarely that infested birds arenoticed. Close examination of David Playle’s photographs suggests that this bird had at least 110feeding ticks. The larger ticks will be females, the smaller ones nymphs. Despite having handled manythousands, and looked at tens of thousands, of Puffins over 40 years, this is by far the most extremecase of infestation by ticks that I have come across.

‘Doubtless this Puffin will have lost a substantial quantity of blood and it may also have had anallergic reaction to so many ‘bites’. As if this was not enough, these ticks carry a range of pathogensincluding viruses and a neurotropic form of the Lyme disease agent Borrelia garinni. The proximity ofthe ticks may increase the likelihood of pathogen transmission between ticks (a process termed ‘co-feeding transmission’). There would seem plenty of scope for this here! Although alive when pho-tographed, the bird was obviously distressed and its chances of survival (and those of the ticks) musthave been very low.’

The Bedfordshire Bat Group (BBG) monitorsan exceptionally large roost of Soprano Pip-istrelles Pipistrellus pygmaeus on a privatewooded estate in east Bedfordshire. Theroosting site is under the roof of a smallbuilding, which in the evening is lit by spot-lights, making observation of the departing batseasy. The bats emerge from two exit holes in thesoutheast corner, then fly straight into the trees.Counts of bats departing from the roost aremade by the BBG on a fortnightly basisthroughout the summer; in most years, up to600 bats use this roost in the height of summer.

On 7th May 2003, SN & DN recorded a maleEurasian Sparrowhawk Accipiter nisus deliber-ately hunting bats coming out of the roost. Thisbird made at least seven attacks within 30minutes on bats emerging from the exit hole,and caught at least two. These were taken to anoak Quercus tree immediately in front of the

exit hole, where they were ‘plucked’ and eaten.Although a male Sparrowhawk was seen aroundthe roost several times that year and again in2004, hunting behaviour was not witnessedagain, although larger numbers of observersmay have deterred the hawk.

On 19th July 2005, Jude Hirstwood and DOwere waiting for the first bats to leave the roostwhen DO noticed a male Sparrowhawk land ona prominent snag nearby. At 21.16 hrs the firstSoprano Pipistrelle left the roost site, where-upon the Sparrowhawk immediately went afterit at speed. Although they did not see the Spar-rowhawk catch the bat, it was suspected that itdid, and the bird did not return to its perch. On20th July 2005, JH and DN were stationed closeto the exit hole, where they not only saw a maleSparrowhawk sally out to make an unsuccessfulattack, but also observed it land at the entranceto the roost and peer inside.

383British Birds 100 • June 2007 • 381–383

Notes

Eurasian Sparrowhawk attacking Soprano Pipistrelle bat

Sarah & Derek Niemann2 Birch Grove, Sandy, Bedfordshire SG19 1NG

Dave Odell136, Bedford Road, Wootton, Bedfordshire MK43 9JD

EDITORIAL COMMENT Ian Newton has commented: ‘These records reveal when and how captures aremade and suggest pre-planning on the part of the Sparrowhawk.’

Reed Warbler apparently using willow-bark pieces in nest constructionOn 29th June 2006, by a lake on Westhay Moor,Somerset, I saw a pair of Reed Warblers Acro-cephalus scirpaceus fly to perch on a deadbranch of a willow Salix fragilis bush. One ofthe birds, presumably the female, tore at thebark with its bill, collecting several ‘peelings’,and the two birds then flew to a dense part of aPhragmites bed in the water. Shortly afterwards,the pair returned to the same branch andresumed peeling; this was repeated on at leastfour further occasions. I assumed that the ReedWarblers were engaged in nest construction,although the nest was not visible and the

reedbed was inaccessible. At times, snatches ofsong were uttered by the male bird.

Bark strips are not normally used as compo-nents in the nests of Reed Warblers. Campbell& Ferguson-Lees (1972) listed grasses, reed-flowers and moss fragments, with a lining com-prising reed-flowers, grass and occasionalfeathers, wool or hair.

Reference

Campbell, B., & Ferguson-Lees, J. 1972. A Field Guide toBirds’ Nests. Constable, London.

Dr A. P. RadfordCrossways Cottage, West Bagborough, Taunton, Somerset TA4 3EG