The aliens are here, living alongside us.\u00a0 They will do anything to survive and we must be vigilant if we want to preserve life as we know it.\u00a0 I\u2019m not talking about slimy purple creatures from the planet Zob, I\u2019m talking about plants and animals, alien to Britain, that threaten our countryside. So why are these aliens such a threat?<\/p>\n
It is now generally accepted that the World hasn\u2019t always been the way it is today.\u00a0 The vast array of living things on Earth, together with the various and complex ecosystems they make up, have evolved gradually to reach their current levels of complexity.\u00a0 The balance of nature is constantly shifting and changing as the result of an unending battle for supremacy in which every living thing is fighting for survival.<\/p>\n
Given the chance, frogs or even eggplants would dominate the world.\u00a0 Happily, or unhappily \u2013 if you\u2019re an eggplant, they can\u2019t.\u00a0 The spread of an organism is restricted by the availability of suitable environmental conditions, by physical barriers (such as mountains and oceans that it can\u2019t cross) and by other organisms in its surroundings competing with and eating it.<\/p>\n
Environmental changes that alter conditions locally, or even globally, can often trigger major changes in ecosystems that allow new, colonising, organisms to invade and take over.\u00a0 The living things that once dominated can find themselves less able to cope with the new conditions than the invaders and they are forced to either move on or are wiped out.<\/p>\n
Here in Britain we have seen some pretty major changes through the ages as our little Island has drifted slowly North from the equator at a speed roughly equal to the rate at which your fingernails grow.\u00a0 The fossils preserved deep underground in coal seams reveal that 240 million years ago most of Britain was covered by tropical swamp.\u00a0 More recently, the last ice age, 15,000 years ago, covered the majority of the country in glaciers and forced everything south for a long winter.\u00a0 When, nearly 10,000 years ago, things started to warm up again the plants, animals and other organisms we now think of as native to Britain moved in.<\/p>\n
Before humans started travelling around the world, natural barriers effectively kept many ecosystems separate.\u00a0 With the exception of migrant animals there was little opportunity for organisms to travel the world to find suitable new places to live.<\/p>\n
When we started to spread across and colonise the Earth that all changed.\u00a0 Wherever we went, we took domesticated plants and animals with us.<\/p>\n
From the time our ancestors first arrived here from mainland Europe we have been deliberately importing and releasing animals to improve our food supply.\u00a0 As society developed we imported animals to farm for profit, hunt for sport and, occasionally, because we wanted them for decoration.<\/p>\n
Many of these reintroductions failed as conditions weren\u2019t suitable or the introduced organism couldn\u2019t compete with the animals and plants already present.\u00a0 Some succeeded because the alien fitted into a gap or niche in the ecosystem that it could exploit without causing too much hardship for the existing species and it became part of the food web.\u00a0 Others wreaked havoc as the introduced animal or plant managed to out-compete a native species and, in the absence of the natural competition from the other organisms in its native ecosystem it spread out of control.<\/p>\n
The Romans didn\u2019t just bring central heating and the habit of wearing sheets to Britain, they also imported Fallow Deer, Edible Dormice and, quite possibly Rabbits.\u00a0 Rabbits were again imported in the 12th Century.\u00a0 Today, there are now tens of millions of them, hopping around, grazing pastures and eating farmer\u2019s crops.<\/p>\n
Birds have also been introduced.\u00a0 Common Pheasants, a familiar sight in the countryside, were imported for food in the twelfth century and soon spread nationwide.\u00a0 These were followed, in the seventeenth century, by a host of birds imported principally to make the countryside \u2018prettier\u2019.\u00a0 These included: Canada Geese, Reeves Pheasant, Lady Amherst\u2019s Pheasant and the Red-Legged Partridge.<\/p>\n
The habit of introducing species in an attempt to make Britain more \u2018interesting\u2019 reached its peak in Victorian times.\u00a0 There was even a society, \u2018The Acclimatisation Society\u2019, whose stated aim was to introduce and hybridise exotic animals and plants from far off lands.\u00a0 Many animals released during this period are, however, still with us.\u00a0 The Edible Dormouse, the little Owl, Sika Deer, Reeve\u2019s Muntjac (another kind of deer), Chinese Water Deer and, of course, the Grey Squirrel.<\/p>\n
The deliberate release of alien organisms into the wild in Britain is now illegal.\u00a0 However, another route used by aliens to invade, is still open.<\/p>\n
Wherever humans have travelled, certain animals, most notably Black Rats, Brown Rats and House Mice have followed close behind.\u00a0 Some pretty damaging alien invaders have managed to sneak in to the country this way, and continue to do so.\u00a0 Today, with people and goods zipping around the earth by ship and plane more than ever before, the opportunities for biological hitchhikers are just becoming better and better.<\/p>\n
If you go to a beach and look at the shells that have been washed up, you don\u2019t have to search long before you find a Slipper Limpet.\u00a0 On the South coast there are whole beaches almost entirely made up of their washed up shells.\u00a0 Amazingly, they are an invader that sneaked into Britain when we attempted to import American Blue-Point Oysters in the 19th Century.\u00a0 They were imported to help save the British or Edible Oyster from being wiped out through over fishing, or at least that was the plan.\u00a0 However, the Slipper Limpets, which compete with the Oysters for space and another shellfish invader, the American Oyster Drill; which actually hunts Oysters, have only made the situation worse.<\/p>\n
Some pretty large things have escaped into the countryside too.\u00a0 In the 1920\u2019s Muskrats from North America and Coypu, from South America were imported to be farmed for their fur.\u00a0 They escaped and colonised local rivers causing damage by eating waterside vegetation, digging up riverbanks and causing floods.\u00a0 With no predators to control their numbers, the only solution to the problem was to exterminate them.\u00a0 Muskrats were eliminated by 1935 but the Coypu proved more difficult.\u00a0 However, it was finally eradicated, as far as we know, in 1989.<\/p>\n
The North American Mink, also imported for its fur has proved more troublesome.\u00a0 The Mink was first recorded breeding in the wild in 1957, since then, it has spread throughout the country.\u00a0 Mink are aggressive predators and have had a big impact on populations of ground nesting birds, small rodents (including the now rare Water Vole), fish and its competitors.\u00a0 It is now so widespread that eradicating it is no longer an option.\u00a0 However, the increased competition from Otters over recent years appears to be forcing it out of some areas.<\/p>\n
Plants too have escaped into the wild.\u00a0 One of the most famous is Rhododendron; popular with gamekeepers for the ground cover it provides and loved by gardeners for its beautiful flowers.\u00a0 They had no difficulty escaping into the wild and are exceptionally good at taking over.\u00a0 In addition to being evergreen and able to keep light away from low growing plants they are highly toxic so herbivores don\u2019t munch them.\u00a0 They produce millions of seeds, can re-grow from small fragments of root or shoot left in the ground and are resistant to all but the strongest weed killers.\u00a0 In Wales where I live, whole mountainsides are now covered in them and the cost of removing them has been put at tens of millions of pounds.<\/p>\n
Enthusiasts are still demanding exotic plants for their gardens and ponds.\u00a0 Many of these are known to be fast-growing invasive species that have already caused harm to ecosystems both here and elsewhere.\u00a0 In spit of this, the plants are sold without license or even a warning that their escape into the wild could cause great harm.\u00a0 Exotic animals continue to enter Britain via the pet trade and are, once again, sold without warning.\u00a0 Following the craze for owning red-eared terrapins around ten years ago, many were dumped by pet-owners in lakes and ponds where they have wreaked havoc.\u00a0 None have bred here yet, it\u2019s too cold for them, but they might manage it one day.<\/p>\n
Ships continue to criss-cross the ocean, carrying biological hitchhikers attached to their hulls or in their ballast water.\u00a0 In order to keep them floating at the right height when they are not carrying a full load of cargo ships take on water.\u00a0 When they get to their destination, they dump it.\u00a0 This has enabled the larvae and seedlings of a number of organisms to jump from one side of the world to the other.\u00a0 Most never travel far from the port where they enter the country, however, others are becoming international pests, clogging waterways and invading ecosystems.<\/p>\n
The International Union for the Conservation of Nature recently listed \u2018species translocation\u2019 as the second greatest threat to biodiversity on Earth after habitat loss. \u00a0Once again it seems we are ignoring the lessons of the past and storing up more problems for the future.\u00a0 The aliens are moving in, and they\u2019ll change the world forever if we let them.<\/p>\n ","protected":false},"excerpt":{"rendered":"
The aliens are here, living alongside us.\u00a0 They will do anything to survive and we must be vigilant if we want to preserve life as we know it.\u00a0 I\u2019m not talking about slimy purple creatures from the planet Zob, I\u2019m talking about plants and animals, alien to Britain, that threaten our countryside. So why are […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false},"categories":[3,4],"tags":[5,23,6],"jetpack_featured_media_url":"","jetpack_publicize_connections":[],"jetpack_shortlink":"https:\/\/wp.me\/p2VEjn-7","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/7"}],"collection":[{"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7"}],"version-history":[{"count":5,"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/7\/revisions"}],"predecessor-version":[{"id":9,"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/7\/revisions\/9"}],"wp:attachment":[{"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.howiewatkins.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}