Yorkshire has produced evidence of ninety-nine species of British Mammals past and present.

Excavations in Pennine, North Yorkshire and South Yorkshire caves, river and lake sediments have revealed skeletal remains of twenty species only known from fossil evidence.

Eleven species have become extinct in historic times. Having two major estuaries (Tees & Humber) and a vast North Sea coastline the list includes twenty-two sea mammals (Seals, Whales, Dolphins & Porpoise).

The range of topographies and terrestrial habitats from reedbeds to ancient woodland, upland moors to lowland heath, hay meadows to urban sprawl all add to the tremendous diversity. These include sixteen Bats (one of which, the Alcathoe’s Bat, was only discovered new to science in 2001), five Insectivores (Hedgehog, Mole & Shrews), three Lagomorphs (Rabbit/Hares), fifteen rodents (Squirrels, Dormice, Rats, Mice & Voles), eighteen carnivores (Cats, Dogs, Hyenas, Bears, Weasels), two elephants (!), seventeen Ungulates (Horse/Rhinoceros/Pigs/Hippos/Goats/Cattle and Deer), and one Marsupial. Amongst all these are twelve introduced species.

Yes folks, where mammals are concerned ‘we are living in interesting times’ (!).

This is a fascinating and dynamic period to be studying Yorkshire Mammals. Species thought to have become rare or extinct during the 19th century (Polecat, Pine Marten, and Red Squirrel) are on their way back and the Dormouse is being re-introduced. The Otter, all but wiped out through pesticide pollution during the 1950s-60s is back on most river systems. The American Mink (naturalised from escapees from commercial mink farms in the 1950s and 60s), in the absence of polecats and otters, spread through Yorkshire’s river and canal networks but is now in decline.  The Water vole, on the decline for decades, was pushed to endangered status by Mink predation. The familiar Hedgehog, once so numerous in urban gardens, has undertaken a sudden decline.

Changes in the ecology of the North Atlantic and arctic waters have brought Harp Seal, Hooded Seal and Humpback Whale to our shores in recent years. The Roe Deer, lost for centauries, has spread from the north, colonising new forestry plantations. The Muntjac Deer has spread here from the south by progressive natural dispersal from the midlands and by intermittent introductions for sporting purposes. Fluctuations in populations of the introduced Rabbit, only a significant component of our mammal fauna since the 18th century, have a major effect on predator species such as Polecat, Stoat and Weasel. Foxes, once managed for rural sporting purposes has now become a feature of some large urban areas such as Sheffiled, Leeds and Bradford.

Mammals ~ Contacts and Recorders


Dr Colin Howes Tel: 01302 811037 email:

Mammals Sub-Sections

Mammal News