Britain's lost lynxes and wildcats

You might have noticed very little/no activity here over the past two weeks: partly this is because I'm very busy (preparing for Dinosaurs - A Historical Perspective, among other things), but it's also because I currently have no internet access at home. Sigh. In an effort to add something new, here's the long-planned, third and final part in the series on Europe's cat fauna, adapted from the Big Cats in Britain talk 'The deep time history of Britain's felid fauna'. In a previous article we looked at homotheres, lions and leopards, and in a second one at jaguars, pumas and cheetahs. This time round we deal with the smaller cats: the lynxes, and the members of the domestic cat lineage...

Lynxes are instantly recognisable: they're proportionally long-limbed, they have a very shortened tail, a facial ruff and tufted ears, and they also have a reduced dentition compared to most other cats (Russell et al. 1995). Three lynxes inhabited Europe during the Pleistocene, and two of these are still with us, the large, ungulate-killing Eurasian lynx Lynx lynx and the much smaller Iberian lynx Lynx pardinus [Eurasian lynx image above taken from wikipedia]. The third species was rather different from living lynxes: it's called Lynx issiodorensis, the Issoire lynx, and it had shorter, stockier limbs and a proportionally bigger head than living lynxes. It fact it was proportioned far more like a pantherine cat like a leopard, and its comparatively large size and big cat-like proportions mean that its remains have sometimes been confused with those of European cheetahs and pumas (Hemmer et al. 2004).

The Issoire lynx didn't survive into the Holocene, but of course the Iberian lynx and Eurasian lynx did [adjacent image shows restoration of Issoire lynx by Mauricio Antón, together with lynx lower jaws]. The Iberian lynx previously occurred throughout central Europe (Kurtén 1968, Kurtén & Grandqvist 1987) - in fact it's been described as the 'original' lynx of western Europe (Hemmer 1979) - but it's restricted today to the Iberian Peninsula, and here it's critically endangered, with a fragmented population limited to between 300 and 500 individuals (Bartolomé 2001, Johnson et al. 2004). During the Pleistocene, Eurasian lynxes colonised essentially the whole of Eurasia, but persecution, habitat loss and hunting have meant that they're now locally extinct across much of western Europe [map below, from wikipedia, shows Eurasian lynx's current range].

In Britain, the Eurasian lynx has generally been regarded as a Pleistocene animal that failed to make it into the Holocene. However, we now know that this is completely wrong. Eurasian lynxes were definitely still present in England and southern Ireland as recently as 9000 years ago. The English records, one of which comes from Devon and the other one from Derbyshire, have been carbon dated: both gave ages of 8800-9500 years before present (Coard & Chamberlain 1999, Bronk Ramsey et al. 2002). That's all pretty good: it shows that lynxes were still in Britain during the Holocene. However, in 1997 came the surprising news that Eurasian lynxes had in fact survived in Scotland until as recently as the 3rd century AD.

Radiocarbon dating of a lynx discovered in 1927 in Reindeer Cave in Sutherland showed that the specimen was about 1770 years old (Kitchener & Bonsall 1997). Further radiocarbon dating of lynx bones from North Yorkshire, published in 2006, revealed even younger ages of about 1550 years old, dating these specimens to the 5th or 6th century (Hetherington et al. 2006). In their paper on these modern-era lynxes, David Hetherington and colleagues noted that a word for lynx - llewyn - was used in various 7th century stories and lullabies, all of which originated from north-western England, roughly the same area where the 5th or 6th century lynx specimens came from. And we know from pollen data that this area was well forested at this time, showing that it remained good potential lynx habitat.

So it seems that lynxes persisted in north-western England until the 7th century at least, and of course it's possible and likely that they survived even more recently than this (the few specimens that have been carbon dated are very unlikely to represent the youngest specimens that exist). Quite why and how lynxes then became extinct in Britain - especially when they survived in Scandinavia and elsewhere in Europe - is open to speculation; it's assumed that deforestation, hunting and persecution did the lynx in. Is it conceivable that they survived from the 5th, 6th or 7th century to even more recent times? Various zoologists in the past - including Bernard Heuvelmans and H. G. Hurrell - have suggested exactly this, and of course we have pretty good historical accounts, like William Cobbett's account from the late 1700s, that seem to describe late-surviving British lynxes. Given the massive impact of people on Britain's mammal fauna within the last couple of hundred years, I personally think that the idea that any mid-sized or large mammal might have survived undetected is very unlikely if not impossible. However, if you'd asked an expert 20 years ago as to whether lynxes might have survived to even the 5th century, I think you'd have been laughed at, so perhaps we should be prepared to be surprised again.

The not so Scottish wildcat

Finally, we come to the smaller cats. Conventionally it's been thought that, within recent history, the British Isles have only ever been home to a single small cat species, and this is Felis silvestris, the species most usually referred to (in Britain) as the Scottish wildcat. Of course, this name is entirely inappropriate given that the present restriction of the wildcat to Scotland is an artefact of human persecution: until very recently, the wildcat occurred across essentially the whole of Britain (even occuring in Ireland during the Holocene (Sommer & Benecke 2006), contrary to conventional wisdom).

Human persecution and habitat destruction led to the decline of the wildcat: by about 1800, it had been eradicated from much of southern and central England, by about 1850 it was mostly gone from England entirely, and by the late 1800s it was essentially restricted to the Scottish highlands (Langley & Yalden 1977). This historical pattern of decline was worked out by Peter Langley and Derek Yalden in 1977, but there are enough English sightings of wildcats from the 1800s and 1900s to suggest that small populations might have persisted outside of Scotland. Alternatively, wildcats might have successfully recolonised parts of the country, or been re-introduced to southern regions where they had locally become extinct.

Wildcats interbreed with domestic cats wherever the two meet, meaning that pure-bred wildcats are very rare, if not critically endangered, and this is a problem not just restricted to Britain but affecting wildcats in mainland Europe and Africa as well (Pierpaoli et al. 2003, Yamaguchi et al. 2004). Where hybridisation has occurred, wildcat characteristics continue to crop up in the hybrids, and the result is a continuum with domestic cats at one end, true wildcats at the other, and a range of intermediates in the middle (French et al. 1988, Daniels et al. 1998, Kitchener 1998, Reig et al. 2001). Exactly how and where we draw the line between 'intermediates' and 'true' wildcats is a thorny problem, compounded by the fact that some historical type specimens are apparently hybrids.

Exotic small felids in the British record

Until very recently it was thought that the wildcat was the only small felid that ever inhabited the British Isles within geologically recent times. This idea was challenged in 1997 when a fossil Swamp cat Felis chaus (or Jungle cat) was discovered at Aveley in Essex, in sediments dated to the Middle Pleistocene (Schreve 2001a, b). Unfortunately we only have this one specimen at the moment, and we essentially know nothing about the prehistoric distribution of the Swamp cat in Britain, both in term of geography and in terms of how recently it went extinct.

In fact similar comments can be made about the distribution of the Swamp cat in Europe as a whole: several fossils of this species have been reported from the Middle and Upper Pleistocene of Greece, Germany and France, but all are questionable and Hemmer (1979) wrote that they required confirmation. The absence of the Swamp cat from Holocene sediments in Britain as well as from the rest of Europe suggest that it didn't survive until particularly recently, but - as with the lynxes we looked at a moment ago - evidence either way is very thin on the ground and we need more data. The Aveley specimen has yet to be properly described but a full description will appear soon (D. C. Schreve pers. comm. 2008).

Even more poorly known than the presence of swamp cats in Britain is the suggestion that African wildcats once occurred in the British Isles as well: Scharff (1906) described some lower jaws from Ireland and identified them as being particularly close to Felis silvestris libyca, the African wildcat [adjacent image shows Scharff's Irish cat jaws compared with others]. Based on bones discovered in Edenvale and Newhall caves in County Clare, Scharff thought that there were actually two Irish wildcats - a large one and a small one. Scharff's identification has been repeated a couple of times since: the implication being that maybe Ireland was home to an endemic wildcat, perhaps one quite distinct from the wildcats of Scotland, England and Wales - but the problem here is that African wildcats are very similar, if not identical, to domestic cats in skeletal and tooth characters. In fact domestic cats originated from African wildcats rather than from those of Eurasia, and as a consequence it can be almost impossible to distinguish the bones and teeth of the two.

The Irish wildcat remains didn't come from a prehistoric fauna - they were discovered in layers where domestic mammals were abundant - and, in an evaluation of Scharff's wildcats, Stelfox (1965) concluded that they were domestic cats, the larger ones being males, the smaller ones females. Rather than accept the idea that African wildcats somehow got into Ireland without leaving a fossil record elsewhere in Europe, it does seem more sensible to conclude that Scharff's Irish wildcats were just domestic cats (Fairley 1975).

Additional small cat species might have been present in Pleistocene Europe - there are some doubtful Middle Pleistocene German fossils and more reliably identified Czech fossils that might represent Pallas's cat Otocolobus manul for example (Kurtén 1968, Hemmer 1979) - but there's presently no evidence that additional species occurred in Britain. Incidentally, there is no fossil or archaeological evidence for rabbit-headed cats, an observation which supports the view that they are teratological rather than a genuine taxonomic entity [adjacent image, from wikipedia, shows Pallas's cat].

And that bring us to the end of our look at Europe's cat fauna. The big sabre-toothed cat Homotherium latidens was still present in northern Europe during the Late Pleistocene, but almost certainly didn't persist to the Holocene. Lions remained in Spain and south-eastern Europe until the early Holocene. Leopards inhabited Britain and the rest of Europe during much of the Pleistocene, but by the Late Pleistocene they were gone from northern Europe. The European jaguar lived alongside the leopard in several locations during the Middle Pleistocene. Pumas and cheetahs occurred across Europe and Asia during the Early and Middle Pleistocene. Pumas were present in Britain but neither pumas nor cheetahs seem to have survived into the Late Pleistocene or Holocene. Lynxes definitely survived in Britain until the 1st century AD, may well have persisted until the 6th or 7th centuries, and were perhaps still present even more recently than this. Jungle cats were present in Britain during the Middle Pleistocene but there is as yet no evidence that they survived into the Holocene. There's no evidence that African wildcats were present in Ireland, despite suggestions from the early 1900s that they were. Finally, European wildcats were here throughout the Pleistocene and Holocene, and have just about managed to survive until today.

Europe's cat fauna - and Britain's cat fauna - was obviously a lot more diverse in the recent past than it is today. In fact, we have a thoroughly impoverished fauna compared to what we 'should' have.

That's all for now. Will be seeing some of you on Wednesday (23rd April) at the Natural History Museum for the CEE's Modern Functional Anatomy Workshop. Will be discussing what happened there here at Tet Zoo, internet connection permitting.

Refs - -

Bartolomé, J. 2001. A creature great and small. BBC Wildlife 19 (8), 22-27.

Bronk Ramsey, C., Higham, T. F. G., Owen, D. C., Pike, A. W. G. & Hedges, R. E. 2002. Radiocarbon dates from the Oxford AMS system: Archaeometry datelist 31. Archaeometry 44 (supplement 1), 1-149.

Coard, R. & Chamberlain, A. T. 1999. The nature and timing of fauna change in the British Isles across the Pleistocene Holocene transition. Holocene 9, 372-376.

Daniels, M. J., Balharry, D., Hirst, D., Kitchener, A. C. & Aspinall, R. J. 1998. Morphological and pelage characteristics of wild living cats in Scotland: implications for defining the 'wildcat'. Journal of Zoology 244, 231-247

Fairley, J. 1975. An Irish Beast Book. The Blackstaff Press, Belfast.

French, D. D., Corbett, L. K. & Easterbee, N. 1988. Morphological discriminants of Scottish wildcats (Felis silvestris), domestic cats (F. catus) and their hybrids. Journal of Zoology 214, 235-259.

Hemmer, H. 1979. Fossil history of living Felidae. Carnivore 2: 58-61.

- ., Kahlke, R.-D. & Vekua, A. K. 2004. The Old World puma - Puma pardoides (Owen, 1846) (Carnivora: Felidae) - in the Lower Villafranchian (Upper Pliocene) of Kvabebi (East Georgia, Transcaucasia) and its evolutionary and biogeographical significance. Neues Jahrbuch fur Geologie und Paläontologie, Abhandlungen 233, 197-233.

Hetherington, D. A., Lord, T. C. & Jacobi, R. M. 2006. New evidence for the occurrence of Eurasian lynx (Lynx lynx) in medieval Britain. Journal of Quaternary Science 21, 3-8.

Johnson, W. E., Godoy, J. A., Palomares, F., Delibes, M., Fernandes, M., Revilla, E. & O'Brien, S. J. 2004. Phylogenetic and phylogeographic analysis of Iberian lynx populations. Journal of Heredity 95, 19-28.

Kitchener, A. C. 1998. The Scottish wildcat - a cat with an identity crisis? British Wildlife 9, 232-242.

- . & Bonsall, C. 1997. AMS radiocarbon dates for some extinct Scottish mammals. Quaternary Newsletter 83, 1-11.

Kurtén, B. 1968. Pleistocene Mammals of Europe. Aldine Press, Chicago.

- . & Grandqvist, E. 1987. Fossil pardel lynx (Lynx pardina spelaea Boule) from a cave in southern France. Ann Zool Fennici 24, 39-43.

Langley, P. J. W. & Yalden, D. W. 1977. The decline of the rarer carnivores in Great Britain during the nineteenth century. Mammal Review 7, 95-116.

Pierpaoli, M., Birò, Z. S., Herrman, M., Hupe, K., Fernandes, M., Ragni, B., Szemethy, L. & Randi, E. 2003. Genetic distinction of wildcat (Felis silvestris) populations in Europe, and hybridisation with domestic cats in Hungary. Molecular Ecology 12, 2585-2598.

Reig, S., Daniels, M. J. & Macdonald, D. W. 2001. Craniometric differentiation within wild-living cats in Scotland using 3D morphometrics. Journal of Zoology 253, 121-132.

Russell, A. P., Bryant, H. N., Powell, G. L. & Laroiya, R. 1995. Scaling relationships within the maxillary tooth row of Felidae, and the absence of the second uper premolar in Lynx. Journal of Zoology 236, 161-182.

Scharff, R. F. 1906. On the former occurrence of the African wild cat (Felis ochreata Gmel.) in Ireland. Proceedings of the Royal Irish Academy 26, 1-12.

Schreve, D. C. 2001a. Mammalian evidence from Middle Pleistocene fluvial sequences for complex environmental change at the oxygen isotope substage level. Quaternary International 79, 65-74.

- . 2001b. Differentiation of the British late Middle Pleistocene interglacials: the evidence from mammalian biostratigraphy. Quaternary Science Reviews 20, 1693-1705.

Sommer, R. S. & Benecke, N. 2006. Late Pleistocene and Holocene development of the felid fauna (Felidae) of Europe: a review. Journal of Zoology 269, 7-19.

Stelfox, A. W. 1965. Notes on Irish "wild cat". The Irish Naturalists' Journal 15, 57-60.

Yamaguchi, N., Kitchener, A. C., Driscoll, C. A., Ward, J. M. & Macdonald, D. W. 2004. Craniological differentiation amongst wild-living cats in Britain and southern Africa: natural variation of the effects of hybridisation? Animal Conservation 7, 339-351.