Exotic and Evasive – Escaped Mammals in North East England

This article is an update of the “Escaped Mammals” chapter from the “Extinct and Evasive” section of the 2012 book, “Mammals, Amphibians and Reptiles of the North East”, in which I listed all of the records known to me, of species’ not normally found in Britain that had turned up locally.  Since 2012, a few more individual animals have turned up on the loose in North East England, plus an unlikely Victorian escapee was brought to my attention.  All of the records listed in the table below are thought to be of individuals that have escaped or been released and there is no indication of any of them becoming established.  The only escaped species for which there is any reason to believe it may have bred in the North East is the American Marten Martes americana casuarinas and as it may have hybridised with Pine Marten it was dealt with under the species account for Pine Marten in the book.   The table also excludes reports of exotic cat species, which had their own chapter in the book. That chapter can be viewed on this blog under “Exotic cat reports in north east England”,

Escaped mammals have a long history in the North East.  Included in the inventory of the mammals found in a Roman granary in South Shields are remains from two Garden Dormice, Eliomys quercinus.   There is no indication that this species has ever been native or otherwise established in Britain, so it is more likely that these are escapees, potentially from animals kept for the table.  In 1858, a “singular looking animal” was killed in Redmarshall, when the farmer thought it might be, “a savage carnivorous animal that would destroy all the poultry in the neighbourhood”.  To be fair to the farmer, when first examined by a local naturalist, John Hogg, a Fellow of the Linnean Society, the closest British quadruped that it vaguely resembled was the yellow-breasted Pine Martin [sic].  However, closer examination of its teeth showed it not to be a carnivore, while an inspection of its feet and somewhat prehensile tail indicated it to be some opossum-like or marsupial species, a fact not immediately obvious as this was a male so didn’t have a pouch.  It turned out to be a Brush-tailed Opossum Trichosurus Vulpecula, and it later transpired that it had escaped from Aycliffe, some seven miles to the west. It had been on the loose for 14 days before it was killed and had built a nest of straw in a poplar tree so appeared to be adapting to life in the British countryside. 

While the table lists all of the modern records of escaped mammals that I am aware of that have been at large in the North East, doubtless there will have been a number of others.  For example Baker (1990) plotted the distribution of 22 records of Raccoon Procyon lotor found out of captivity in the UK between 1970 and 1989; one of the dots on his map was broadly in the Middlesbrough/Billingham area. 

That certain exotic species haven’t become established is perhaps a little surprising.  Siberian Chipmunks had quite a boom in popularity as pets in the 90s and I can attest from my own experience to the ease with which they can escape from their enclosure (though fortunately with the shed door closed on each occasion in my case).  Also Raccoons and Coatis were removed from the Dangerous Wild Animals Act in 2007, which meant that a licence and accompanying inspections for husbandry and security were no longer required in order to keep them.  More recently however these three species have been included in the Invasive Alien Species (Enforcement and Permitting) Order 2019.  The Order, which also applies to Raccoon Dogs as well as certain species which are already established in Britain, namely Muntjac and Grey Squirrel, makes it an offence to keep, breed, sell or exchange individuals of those species.  Owners who had the animals prior to the Order can keep them for the duration of the animal’s life but the animal must be neutered.  Consequently, it would seem that the chances of those species becoming established in future are now fairly slim.

Table 1: List of mammals recorded as presumed escapees in the North East.  Escapees are single animals unless otherwise indicated

Date	Species	Location	Notes
Late 1960s	Smooth coated Otter  Lutrogale perspicillata	Stanley	Escaped from Stanley Zoo.  Believed to have escaped into the River Team.
1983	Porcupine Hystrix sp	Shincliffe	Seen in bushes near Rose Tree pub; known to have been present for 2-3 years.
Mid 1980s	Golden Hamster Mesocricetus auratus	Darlington	Brought in by cat.
c1987	Chinchilla Chinchilla lanigera	Pow Hill Country Park	A group of three were captured.  It was thought that they had not been long out of captivity as they were easily caught.
1980s	Chipmunk – spp unknown	Newcastle	Live specimen in school grounds – recaptured.
Late 1980s	Chipmunk – spp unknown	Thropton, near Rothbury	Killed by cat.  Specimen now in Great North Museum: Hancock.
November 1992	Red necked Wallaby Macropus rufigriseus	Lanchester	Escaped from Acorn Bank garden centre.  It was captured within 3 days having made it as far as Dryburn Hill in Durham City.
1993	Wild Boar Sus scofra	Brancepeth	Northern Echo report.
1995	Red necked Wallaby Macropus rufigriseus	Lanchester	Escaped from a garden centre and was present on the Malton reserve for a couple of weeks.  Fate unknown.
1996	Red necked Wallaby Macropus rufigriseus	Wark area	Seen on the loose.
1997	Arctic Fox Alopex lagopus	Alnwick	Shot by gamekeeper while eating (scavenging?) a lamb.
1998	Raccoon Procyon lotor	Darlington	Found in a shipping container from the USA at Cummins Engines.
2001	Wild Boar Sus scofra	Chopwell Woods	On the loose for several days before being killed by a car.
2001	Brush-tailed Possum Trichosurus vulpecula	Riding Mill	One was seen in the wild over several months during which time it evaded attempts at capture.  It was thought to have been an escapee from a private collection near Consett.  It eventually turned up as a road casualty.
2001	Arctic Fox Alopex lagopus	Iveston	Seen outside the front door of house at night.
ca2002	Raccoon Procyon lotor	Castle Eden Walkway, Stockton	Notice put up offering reward for lost Raccoon.
2005	Red necked Wallaby Macropus rufigriseus	Elwick, Hartlepool	Escaped and not recaptured.
2007	Red Deer or Wild Boar	Elwick Hartlepool	Large print found in a stream bed in woodland. Cast taken, showing dew claws. DEFRA unable to say whether it was from Red Deer or Wild Boar.
2008	Wild Boar Sus scofra	Between Hexham & Corbridge	Road casualty – the dead animal was photographed.
2008	Wild Boar Sus scofra	Sedgefield	Road casualty near Hardwick Hall, Sedgefield.
2009	Red necked Wallaby Macropus rufigriseus	Kielder	Escaped from the Bird of Prey centre.
2010	Raccoon Procyon lotor	Shadforth, Durham	Filmed by Durham Wildlife Trust in a private garden.  It had been visiting the garden for the previous two years though it disappeared shortly after it was filmed.
2011	Chipmunk – spp unknown	Stobswood, Morpeth	Seen on the loose; unclear whether more than one animal involved.
2012	Raccoon Procyon lotor	Sunderland	Seen in a private garden for several days in July 2012.  Durham Wildlife Trust has a report of a Raccoon in Sunderland for the previous two years which may be the same individual.
2012-13?	Raccoon Procyon lotor	Sunderland area	Found as a road casualty
2012-13?	Raccoon Procyon lotor	Sunderland area	Recaptured.
2014	Raccoon Dog Nyctereutes procyonoides	Wallsend	The Metro reported that it had been recaptured
2014	Raccoon Procyon lotor	Bardon Mill	Shot while raiding a hen house
2018?	Coati Nasua nasua	Hamsterley Forest	Captured.  Transferred to an animal rescue sanctuary in Hartlepool in January 2019
June 2019	Raccoon Procyon lotor	Medomsley	Seen crossing the road in the early hours of the morning