UK extinct species and imported species – Part 2

Grey squirrels- invaders

These animals cause significant damage to woodland throughout the UK. They were first introduced to Henbury park in Cheshire, but have quickly spread. Being less reliant on trees than red squirrels they have done very well though it is thought that red squirrels were not doing well anyway. A great deal of money and time has been spent trying to control their spread, as they often carry squirrel pox which kills red squirrels quickly, meaning they don’t share land for long.

Pine martens – locally extinct across much of Britain

These arboreal predators are thought to be the reason that the grey squirrel has not been able to enter large parts of Scotland. As the grey squirrel spends more time on the ground and is less acrobatic than the red squirrel they do not survive in areas where pine martens are found. Indeed in Ireland, the grey squirrel has almost been eradicated due to the recovery of the pine marten. In Britain, the pine marten was eradicated because it would often attack game birds on shooting estates. I believe however that it is time to reintroduce pine martens into Southern England. From a purely financial reasoning, it does not make sense that because of the bird hunting estates within England, we are missing a predator which would otherwise save all landowners money by removing Grey Squirrels. If indeed it is necessary for Asian birds to be imported into the UK for shooting, those estates should have to erect pine marten proof fencing around their land instead. Encouragingly, though it wasn’t until this little predator was covered on BBC that we discovered small remaining populations within Wales and northern England. As such given access to suitable land this animal could recover with little help from humans.

Wolves – absent

If we wish to rebalance the British ecosystem, wolves are perhaps the most important species. Unlike other European large predators they create a climate of fear. While they do ambush their food on occasion they are also capable of effectively hunting animals down in open country over long distance unlike both bears and lynx.

This animal was the most feared in the UK in the immediate time before it was eradicated, however at earlier times it was also one of the most favoured. During periods where we had a hunter gatherer system, wolves would help humans hunt as this was a successful way of surviving. The wolves who were most comfortable lived with humans more and more of the time until they became the domestic dog (over a long period of time). I fully agree that the ecosystem in the UK is different now to what it was then, but two things should be borne in mind, in terms of evolutionary time scales the period since this is a blink of an eye, and while we have a sanitised view of the natural world, would take very little time for the ecosystem to rebalance if given the right reintroduction. A place of note where this was seen was Yellowstone national park, which went through a full recovery of the ecosystem because of the reintroduction of wolves.  Wolf reintroduction led to a a reduction of various forms of deer, this lead to a recovery of the willow that they liked to eat, that grew along the rivers; this willow was very good for beavers who rapidly recovered population numbers. They built dams that slowed the course of the river and improved the rest of the ecosystem.

Returning of predators to the UK would require some changes to livestock keeping in this country, but the current position is unsustainable, and with relatively simple changes livestock losses would be minimal. From a financial point of view it also makes sense. Currently the UK looses roughly half a billion a year to deer collisions with cars as well as many lives lost on these collisions. Reintroduction of wolves would reduce this to negligible numbers, because roads are inherently open spaces and so deer would start to stay away from them as much as possible (it would be an easier place to find prey). While other predators would likely also reduce the problem they do not create the climate of fear that wolves do, so the problem is generally reduced by a similar percentage to the reduction in the prey species population. Analysis suggests that even if half of the wolves took to specialising in eating livestock this would only cost 100 million, a net gain of 400 million. With simple preventative methods this could be reduced to very low predation. Romania has thousands of wolves and large numbers of sheep, they have a surprisingly low loss rate because they have taken simple protective measures.

Another big advantage of reintroducing wolves can be seen elsewhere. The UK many species of deer that should not be in the UK but have been introduced over the last millennium. Many of these species don’t appear to do damage but are likely to do so some time in the future.

While travelling in Spain we spent some time in some mountains in the north west of the country. About a decade ago some people had decided to introduce Fallow deer into the local area. It is thought that fallow deer originate in the middle east, though there is some argument as to how large their natural range was before humans started introducing them to more areas of Europe. At any rate a couple of hundred were introduced. In the winter that followed every single one was taken by the local wolves. While this was a localised small introduction, over time wolves could be expected to complete a similar task in the UK, at least in the wilder areas.

Lynx – absent

A similar situation to the wolf above, the lynx would reduce the problems of deer collisions and too many deer in the woods. They are an ambush predator so will not have a significant effect on behaviour but are likely to have a significant effect on the number of deer. Also it has been noticed that in areas where lynx still exist foxes live at far lower densities, which is likely to lead to a reduction on the predation of lambs as foxes often are a real problem in this area. Part of the problem with foxes in the UK is that they are a mid level predator fulfilling the role of apex predator due to all animals further up the food chain being removed. Lynxes actively hunt and eat foxes as part of their diet, as such foxes would quickly reduce in numbers and start behaving more naturally. As for livestock problems, in the UK lynx are likely to cause very few. Lynx are predators that rarely leave the cover of woodland, and in the UK we do not graze sheep within woodland so it would be unlikely that we would loose many sheep to lynx at all. There is only one country in Europe where significant numbers of sheep are eaten by lynx, and that is Norway, this also happens to be the only country in Europe where sheep are left to wander in the forests. In the UK sheep are not left to wander our woodland so this would not be a problem.

Beavers – Absent

Beavers were hunted to extinction in the UK for their meat, pelts and scent glands. The problem is that beavers are a highly important part of the UK environment and have a huge impact on the rivers that they live in. There are several trial reintroductions going on at the moment in particular Knapsdale in Scotland and on the River Otter in East Devon. There is also a sizeable population in the Tayside river catchment area in Scotland, and this has been declared a trial reintroduction and is being closely monitored.

As well as these trials that are ongoing, there are several places in the UK that are looking at reintroducing beavers, often within a large enclosure to help with regular flooding. While is a full release is preferable I am extremely keen on the idea of beavers being put back to control river flooding, where appropriate, as it will demonstrate the need for them to be released on more general terms. The village of Lydbrook in Gloucestershire has had devastating flooding every year for the last few. The forestry commission, which is overseeing the project will release 2 adult and 2 kits into a 6.5 acre fenced area above the village. The beavers will then create their dams, and these will slow the floods of water, which allows the rivers to carry it away over several hours and days. This will mean that the river will not be overwhelmed but will be able to contain the water within its banks.