List of endemic species of the British Isles

The British Isles have few endemic species due to past frequent glaciations and because of the proximity to Continental Europe and former land bridges which enabled species to re-colonise the islands from the continent following glaciations.

British Conservationists often describe this as a “wiped clean effect” with repeated glaciations forcing many species out of the modern area of the islands to more southern latitudes in Europe and perhaps even driving some species extinct.

Some species which were present in Britain before past glaciations, often during periods with a warmer climate than now failed to return after the Last Glacial Maximum. Amongst these are Rhododendron ponticum and rabbits, now considered invasive and non-native.

A species is only deemed native if it reached the British Isles without human intervention (either intentional or unintentional). That means that to be native the species must have reached Britain before the land bridge joining Britain to the continent was submerged. Alternatively species can also be native when they have flown or swum to Britain as is the case with many bird species which arrived after the submersion of the land bridge, a recent example is the collared dove which arrived in the 1950s, this also applies for plants which spread seed in the wind.

Most endemic species to the British Isles are considered to be subspecies of a larger species, with mutations or adaptations slightly changing the species in the islands or in certain localities. Within time many subspecies may become fully fledged, new species, although any potential future glaciations of the British Isles would possibly drive many subspecies extinct or out of the islands to the continent.

A few endemic species are Arctic-Alpine species, survivors of Arctic species of plants and animals which either adapted to the warming climate or became isolated in suitable areas of mountains or lakes which still retained a suitable micro-climate. A common misconception is that the entirety of the British Isles was under glaciers and was uninhabitable both for humans, plants and animals. Whilst unsuitable for most species, a number of Arctic species survived in the areas not under glaciers in southern areas of England, Wales and South West Ireland and were either driven to extinction in the British Isles or to micro-climatic refuges as the climate warmed and the Arctic conditions retreated north.

Most endemic species or subspecies however date to more recent, post-glacial times, many having spread via land bridges or along the Atlantic seaboard of Europe.

Types of endemic species

Fungi

Bryophytes

Plants

Primula scotica, endemic to the north of Scotland

As of 1999, 47 species of flowering plants (430 including microspecies[3]) were considered to be endemic to the British Isles, 32 of them in the "critical genera" Euphrasia, Limonium and Sorbus.[4]

Subsequently, Sorbus pseudomeinichii was discovered on the island of Arran in 2007.[5]

Spiders

Amphipoda (freshwater)

Insects

Some species of insects only occur in Britain:

Birds

Britain has few endemic species of birds but quite a few subspecies. A few Arctic-Alpine species have subspecies in the British Isles, some have been in the islands since the last Ice Age, but many spread in the immediate Sub-Arctic conditions as the ice retreated. Further more these species were latter reinforced by newer arrivals as the climate assumed temperatures and conditions more similar to the present day.

Distribution of white wagtail subspecies, with British pied wagtail (Motacillia alba yarellii) highlighted in blue.

Mammals

Britain has a few subspecies of mammals but no endemic species. Many again are Ice Age survivors that adapted to the new conditions; others arrived in warmer conditions whilst the land bridge still existed.

A wildcat

Aquatic fauna

Cnidaria

The Cnidaria are a group of animals found exclusively in aquatic and mostly marine environments. They include sea anemones, sea pen and corals and their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey.[12][13]

Fish

In some areas of uplands in the British Isles the retreating glaciers left melt water in hollows which had been carved out by the movement of ice. In these, Arctic species of fish survived, due often to the sheer depth of the lakes and the colder temperatures. For the young endemic fish varieties of the British Isles, it is usually controversial whether they should be considered as distinct taxa (species or subspecies) or just as isolated populations of their ancestral species.

As global warming affects the British climate there is some concern for these species, some confined to a handful of lakes. Action has been taken to protect them, as is the case with vendace which has been moved to tarns in nearby mountains due to the cooler temperatures. It is hoped that these will act as refuges should the species die-out in the lower-level lakes where they occur naturally.

Extinct

Distribution

The distribution of endemic species seems to have a North Western bias and with endemic species on the whole showing an oceanic / alpine distribution with most endemics being found in upland areas or islands.

Future

Endemic livestock breeds

Human bred-animals are not usually classified as distinct subspecies but rather breeds which is a similar concept. However some animals such as Iron Age pigs are classified as a distinct species from their wild relatives.

See also

References

  1. ↑ Blackman, Stuart (July 2015). "New Species of the month". BBC Wildlife. 33 (402): 17.
  2. ↑ Holyoak, David T (2009). Bryophytes: Liverworts (Marchantiophyta), Hornworts (Anthocerotophyta) and Mosses (Bryophyta). In Red Data Book for Cornwall and the Isles of Scilly. Praze-an-Beeble: Croceago Press. pp. 72–104. ISBN 978-1-901685-01-5.
  3. ↑ T. G. C. Rich; G. Hutchinson; R. Randall; R. G. Ellis (1999). "List of Plants Endemic to the British Isles". BSBI News. 80: 23–27.
  4. ↑ M. O. Hill, J. O. Mountford, D. B. Roy & R. G. H. Bunce (1999). Ellenberg's indicator values for British plants. Huntingdon: Institute of Terrestrial Ecology. ISBN 1-870393-48-1. ECOFACT Volume 2 Technical Annex.
  5. ↑ "New species of tree discovered on Arran". Scottish Natural Heritage. 14 June 2007. Retrieved 6 November 2013.
  6. ↑ "Britain's rarest spider found at new site, and photographed". buglife. Retrieved 10 February 2016.
  7. ↑ Gainey, P A. Amphipoda. In Red Data Book For Cornwall And The Isles Of Scilly (2nd ed.). Praze-an-Beeble: Croago Press. p. 177.
  8. ↑ "202 Eudarcia richardsoni". UKmoths. Retrieved 7 May 2012.
  9. ↑ Alexander, Keith N A T (2009). Hemiptera. In Red Data Book for Cornwall and the Isles of Scilly. Praze-an-Beeble: Croceago Press. pp. 214–232. ISBN 978-1-901685-01-5.
  10. ↑ Beavis, Ian (2003). "Bees, Wasps and Ants of Scilly". Isles of Scilly Bird and Natural History Review 2002: 168–183.
  11. ↑ Compton, S. G.; Key, R. S. (2000). "Coincya wrightii (O.E. Schulz) Stace (Rhynchosinapis wrightii (O.E. Schulz) Dandy ex A.R. Clapham)". Journal of Ecology. 88 (3): 535. doi:10.1046/j.1365-2745.2000.00477.x.
  12. ↑ Gainey, Paul T (2009). Hydroids, Sea Anemones and Jellyfish (Cindaria). In Red Data Book for Cornwall and the Isles of Scilly. Praze-an-Beeble: Croceago Press. pp. 449–456. ISBN 978-1-901685-01-5.
  13. ↑ Holstein T.; Tardent P. (1984). "An ultrahigh-speed analysis of exocytosis: nematocyst discharge". Science. 223 (4638): 830–833. doi:10.1126/science.6695186. PMID 6695186.
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