Wednesday, 31 October 2012

Not Quite Native




Mute Swan Family by Bernie Sheridan
We live on an island, which for many thousands of years was largely covered in ice. As a consequence very few, if any, land mammals were to be found in Ireland at the end of the last Ice Age. As the ice retreated a process of colonisation began. Some land mammals may have colonised naturally by crossing land bridges connecting us to Britain or even swimming here but a surprising number were certainly introduced here by humans. Human introductions were sometimes accidental and oftentimes deliberate. Some authorities maintain that all surviving land mammals in Ireland are human introductions but this is open to debate.

RABBITS AND HARES

The ubiquitous rabbit is most certainly a human introduction. Rabbits arrived here with the Normans in the 12th century as a domestic food source. The wild rabbits seen here today are the offspring of escapees. The Irish Hare has been here for a considerable period of time and may have been a natural coloniser.

MINK

The mink is a carnivore originally from North America. It was introduced into this country in the 20th century to be commercially farmed for its fur. Many escaped from these enterprises, and misguided and irresponsible individuals deliberately released others. Their initial impact on local wildlife was severe but other animals have now adapted to the mink somewhat. Mink are well established and widespread in Co Waterford.

Shrew by Andrew Malcolm
SHREWS

Greater white-toothed shrew is the latest addition to Irish land mammals. It was first discovered in 2007 in regurgitated barn owl pellets in Counties Limerick and Tipperary. It was most certainly introduced by man probably by accident from the continent. Subsequently Andrew Malcolm confirmed their presence in Co Waterford where they may be relatively widespread.


RODENTS

Although the red squirrel may have colonised Ireland in the early postglacial period it appears to have died by the end of the 18th century possibly as a result of hunting and habitat loss. Red squirrels were subsequently re-introduced from England in the 19th century and became re-established in all counties. At present it is widespread in Waterford but is now facing an imminent danger from the grey squirrel.
The grey squirrel is a North American species. The grey squirrel was introduced from England to Co Longford in1911 and has been rapidly colonising the rest of Ireland. In very recent times it has been observed in Co Waterford. Where red squirrels meet up with their grey counterpart it does not auger well for the reds. Red squirrel populations plummet and often disappear. Grey squirrels being bigger may be able to out compete reds for resources. Greys may also carry a virus to which they are immune but which is lethal to the red squirrel.
Bank voles are a very recent addition to Ireland arriving here in the 1960s. It was almost certainly introduced by man perhaps by accident. It is now established in Co Waterford.
Wood Sandpiper by Colum Flynn
Rats, perhaps surprisingly, are relatively recent arrivals in Ireland and were certainly the result of human activity. The black rat arrived here first from Asia spreading along trade routes used by man. Although it may have arrived here as early as Roman Britain it was certainly here by medieval times when it was associated with Black Death or bubonic plague. The brown rat arrived here much later in the early 18th century again from Asia. Both rats were called Francach in Irish reflecting the belief that they originated from France. Whereas the brown rat has thrived in Ireland the black has all but disappeared and is now probably extinct here.

DEER AND GOATS

Fallow Deer by Liam Cahill
Red Deer, or at least those occurring in Co Kerry, were considered the quintessential native Irish species. However, recent genetic studies suggest Neolithic Irish farmers introduced them. The Normans introduced fallow deer, widespread in Co Waterford, in the 13th century. Sika deer occur in Waterford and were introduced in the 19th century to Ireland.
Wild (feral) goats in Ireland and Waterford are descended from domesticated animals.



RECENT SIGHTINGS AND NEWS

Osprey by Andrew Malcolm
Waders have begun their return journeys from their breeding grounds to their winter refuges. Recent sightings included a little ringed plover (second county record) found by Michael Cowming at Ballinclamper, Clonea and a wood sandpiper at Killongford pool discovered by Colm Flynn, which lingered for a few days. A number of spotted redshanks and green sandpipers were also noted on passage. Andrew Malcolm had a flyover osprey and a minke whale at Ram Head and also upwards of 100 common dolphins at Helvick. Arlo Jacques sighted an eagle species most likely an immature golden eagle. Small numbers of sabine’s gull were observed passing along various points on the coast.
Spotted Redshank by Colum Flynn

Check out www.waterfordbirds.com for local wildlife updates. If you have any questions or comments, please email them to japwatntr@gmail.com. See also the accompanying Blog at www.understandingwaterfordnature.blogspot.com