Download Danger to native species N4/5

Danger to native species
Source 1: http://www.endangeredspeciesinternational.org/amphibians4.html
Source 2: http://www.endangeredspeciesinternational.org/birds5.html
Recently extinct birds
A hundred bird species have vanished since 1600, nearly all due to human activities, chiefly habitat loss, overhunting, and
introduced predators. Island birds are especially vulnerable. Below are some of these birds, the year each was last seen in
the wild, and the cause(s) of extinction.
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King Island Emu (Australia). 1850. Hunting and burning.
Atitlan Grebe (Guatemala). 1986. Introduced fish and habitat loss caused by earthquake.
Guadalupe Storm-Petrel (Mexico). 1912. Introduced cats.
Pallas’ Cormorant (Bering Sea). 1852. Hunting for meat and feathers.
New Zealand Bittern (New Zealand). 1900. Habitat loss.
Pink-headed Duck (India and Myanmar). 1935. Habitat loss and hunting.
Guadalupe Caracara (Mexico). 1900. Intentionally eliminated by hunting and poisoning.
Himalayan Quail (West-central Himalayas). 1876. Habitat loss and possibly hunting.
Bar-winged Rail (Fiji). 1973. Introduced mongooses and cats.
Canarian Oystercatcher (Canary Islands). 1950. Overharvesting of food and eggs..
White-winged Sandpiper (Tahiti and Moorea). 1790. Introduced rats.
Great Auk (North Atlantic Ocean). 1844. Hunting.
Rodrigues Solitaire (Rodrigues Island). 1770. Hunting and introduced cats.
Red-moustached Fruit-Dove (Marquesas Islands). 1950. Introduced owls, rats, and cats.
Paradise Parrot (Eastern Australia). 1927. Habitat degradation, over-collecting, and cats.
Snail-eating Coua (Madagascar). 1834. Over-collecting, deforestation, introduced cats.
Laughing Owl (New Zealand). 1970. Over-collecting, habitat loss, introduced predators.
Jamaican Poorwill (Jamaica). 1859. Introduced predators.
Bogota Sunangel (Colombia). 1909. Habitat degradation.
Bush Wren (New Zealand). 1972. Introduced weasels and rats.
Banggai Crow (Banggai Island). 1900. Habitat loss and degradation.
Grand Cayman Thrush (Grand Cayman Island). 1938. Deforestation and hurricanes.
Chatham Islands Fernbird (Chatham Islands). 1900. Fires, overgrazing, rats and cats.
Lord Howe Gerygone (Lord Howe Island). 1928. Nest predation by rats.
Piopio (New Zealand). 1963. Introduced rats and habitat loss.
Guam Flycatcher (Guam). 1983. Introduced snakes.
Vanderbilt’s Babbler (Sumatra). 1940. Unknown.
Robust White-eye (Lord Howe Island). 1928. Introduced rats.
Kaua’i Oo (Hawaiian Islands). 1987. Rats, pigs, and mosquito-borne diseases.
Huia (New Zealand). 1907. Overhunting and habitat destruction.
Kaua’i Akialoa (Hawaiian Islands). 1969. Habitat loss.
Norfolk Starling (Norfolk Islands). 1923. Hunting, competition with introduced birds.
Bonin Grosbeak (Bonin Islands). 1900. Habitat loss and introduced predators.
Slender-billed Grackle (Mexico). 1910. Habitat loss.
Source 3 : http://www.telegraph.co.uk/news/earth/wildlife/10705527/History-of-grey-squirrels-inUK.html
History of grey squirrels in UK
They were imported as fashionable additions to estates, but grey squirrels soon became the main threat
to the survival of the native red population.
Native to the eastern half of North America, grey squirrels were first introduced to Britain in the 1870s
and are now widely distributed across the UK. With an estimated population of 2,520,000 across the
UK, grey squirrels now heavily outweigh their red counterparts, of which, only around 10,000 -15,000
are thought to exist. Although originally imported as fashionable additions to estates, the grey squirrel is
noted as the main threat to the survival of the native red population. Being larger than red squirrels and
capable of storing up to four times more fat, grey squirrels necessarily stand a greater chance of
surviving tough winter conditions. On top of this, competition is increased by their ability to produce
more young and live at higher densities. However, rivalry between the species is not the only problem.
Grey squirrels are carriers of the Squirrel pox virus, which the reds have no immunity to. It needs only
one grey squirrel to introduce the virus to a local population of red squirrels for the virus to take a hold
and spread throughout the entire group, with devastating effects. Where a grey squirrel has introduced
Squirrel pox, population decline amongst red squirrels is 17-25 times more rapid than through
competition alone. It is unclear when anyone was last prosecuted for not reporting a grey squirrel in
their garden. However, in 2010 a man was ordered to pay more than £1500 for drowning a grey squirrel.
Raymond Eliot trapped the animal because it kept raiding his bird feeding table. After killing it he
became the first person in the country to be convicted of cruelty to a wild animal under the Animal
Welfare Act 2006. Also seeking to protect the birds in his garden, a former Welsh Guardsman was also
prosecuted after catching a number of grey squirrels and releasing them into the wild. Had he simply
shot the squirrels dead, rather than opting for a more humane solution, Mr. Hill would have faced no
charges. Although the future of red squirrels is uncertain, there are still high numbers present in
Scotland. It is also believed that the red squirrel population is stabilising in the North East of England
thanks to efforts in both rural and city areas. In a three month study carried out in 2013 across almost
300 woodlands in the north, the number of red squirrels was found to have risen by 7% compared to the
previous spring. Results also found that pox-carrying grey squirrels were on the decline.
Source 3: N5- SQA- Past paper- 2016
Higher Biology 2016 Q13 p25