Why isthe introduction of species deemed necessary

Seems odd introducing them on moorland given that they would be better in areas where they would kill rats, grey squirrels and more importantly mink ( although I’ve read that they will kill mink but not eat them). Sometimes the reintroduction of an apex predator can actually help other animals and birds. It’s all very complicated and you’d hope they’ve thought it through quite thoroughly.

What effect might pine martens have on ground-nesting birds and songbirds?
Pine martens have co-existed and evolved with many bird species across their European range for thousands of years and should continue to do so in England. Pine martens have a very varied diet and predate the most common bird species in woodlands, such as wood pigeon, jay and blackbird. Pine martens are solitary, live at relatively low population densities and have large home ranges, meaning they are unlikely to affect populations of rare or vulnerable species and their impacts on rare birds will be lower than common predators such as foxes or crows. As a woodland species, pine martens rarely use habitats outside of woodland — they especially avoid large areas of open ground without cover — so are unlikely to encounter bird species which live outside of woodlands, such as grouse.

I’d be more worried about the wild cats than the pine martens. I love cats but they are very,very successful predators on just about anything smaller than themselves that moves. We now keep our cats inside except for an outdoor caged run and the population of lizards ,skinks and tiny honeyeaters has exploded as a result and that is just a very small sample.

I agree. I was focusing more on the pine martens.

I wouldn't worry about grouse which are bred specifically to be shot for fun.

I am always slightly puzzled by the rationale behind introducing or reintroducing species to habitats. I am not sure what they are trying to achieve.

The scientists are maybe trying to save a species, but could it simply be that the natural order of things is that species come and go as the dinosaurs did?

It could be argued that we have caused the loss of some species, but we too are part of the natural order and maybe that is our role, just as grey squirrels tend to wipe out red.

By what criteria do we decide which species should be protected/reintroduced? Who gives us that right to decide?

"It’s all very complicated and you’d hope they’ve thought it through quite thoroughly." - Maybee

The discussions have gone on for years before these introduction/reintroductions, so all situations and predictions have probably be covered. I think one of the points made is that human intervention caused the demise of some important elements of the ecological systems, so human intervention and co-operation is needed to start to redress the balance. The loss of the lynx in forest areas, foe=r example, means that deer have no natural predators keeping their numbers at a steady level, so they proliferate and eat all the young tree seedlings. The forests can't renew themselves automatically and end up full of only old trees with no vigorous younger ones coming along to replace the dying ones.

Keystone species: The Serengeti Rules. This documentary that I’ve watched several times, shows how a keystone species is not necessarily an apex predator but often something much further down the food chain. And that reintroducing a species to an area where it used to live can rejuvenate both the flora and fauna of the whole area. An example of that (although that was an apex predator) was the reintroduction of wolves to Yellowstone.

How are the beaver releases going? There was a lot of initial concern about this.

Pine martens are being re-introduced in some places because they are the chief predators of grey squirrels. Greys spend more time on the ground than red squirrels so are more susceptible to predation by pine martens. It is a way of allowing our native red squirrel population to recover instead of the greys (cute though they are) taking over completely.

I can't see anything wrong with that. It's not as if martens are an alien species (which grey squirrels are). Some other re-introductions are, perhaps, more debatable.

I saw that film MayBee70. Very impressive.

Synopsis
Beginning in the 1960s, a small band of young scientists headed out into the wilderness, driven by an insatiable curiosity about how nature works. Immersed in some of the most remote and spectacular places on Earth—from the majestic Serengeti to the Amazon jungle; from the Arctic Ocean to Pacific tide pools—they discovered a single set of rules that govern all life. Now in the twilight of their eminent careers, these five unsung heroes of modern ecology—Bob Paine, Jim Estes, Mary Power, Tony Sinclair, and John Terborgh—share the stories of their adventures, and how their pioneering work flipped our view of nature on its head. Across the globe, they discovered that among the millions of species on our planet, some are far more important than others. They called these species keystone species, because they hold the natural world together.

The role of keystones is both revelatory and surprising: sea otters help kelp forests flourish, supporting everything from salmon to eagles; wolves enable rivers to run clear and help forests thrive; and the humble wildebeest controls the numbers of trees, butterflies, elephants, and even giraffes on the savanna.

Unfortunately, these deep connections also work in reverse. When keystones are removed, ecosystems unravel and collapse—a phenomenon no one had imagined—or understood until their revolutionary discoveries. But with new knowledge also comes new hope, and these same visionaries reveal the remarkable resilience of nature—and how the rules they discovered can be used to upgrade and restore the natural world. They give us the chance to reimagine the world as it could and should be.

Based on the book by Sean B. Carroll, The Serengeti Rules will forever change the way we see nature.[14]

A wee bit concerned about the proposed lynx project.

Great post MayBee 70. Will look for that book.

For decades it was thought that animal populations were regulated by their food supply. This seemed reasonable enough but in fact in mature ecosystems the key controller is a top predator. Human beings are top, top predators, albeit hardly a part of nature any more, and they have very often removed the key predator from natural ecosystems with consequences we are only just discovering. Without top predators, herbivores run riot, consuming the vegetation. So in Yellowstone national park, Wyoming, healthy tree growth requires wolves to keep down the elk population (they eat tree seedlings). Off the Pacific coast of North America, without sea otters, the giant kelp beds are destroyed by sea urchins. In nature, though not in life, the adage “my enemy’s enemy is my friend” holds true. It isn’t only trees or kelp that benefit: when a top predator is established the number of species that can flourish is dramatically larger than when it is removed. Human beings generally destroy large mammals wherever they find them. We can now see that this has seriously impoverished our world. For Carroll, these revelations are grounded in his love affair with the Serengeti national park, Tanzania, where the greatest abundance of large mammals still flourishes.

Maremia

Great post MayBee 70. Will look for that book.

It’s a documentary too. One of the most amazing things I’ve ever seen!

www.youtube.com/watch?v=AT3X5hKkgOE

It is a way of allowing our native red squirrel population to recover instead of the greys (cute though they are) taking over completely.

I am puzzled as to why the reds are favoured by humans and what gives us the right to interfere in ways that will destroy many greys? How do we justify this value judgement?

Thank you for the link to the documentary - I will look at that.

Luckygirl3

*It is a way of allowing our native red squirrel population to recover instead of the greys (cute though they are) taking over completely.*

I am puzzled as to why the reds are favoured by humans and what gives us the right to interfere in ways that will destroy many greys? How do we justify this value judgement?

Thank you for the link to the documentary - I will look at that.

Greys were never native to the U.K.
Reds are. Their numbers have plummeted since the introductions of greys - and they’re prettier.

Red Squirrels don’t damage trees as much as Grey Squirrels do.

Dipsy

Is anyone else concerned about the introduction of predators such as Scottish Wild Cat a Pine Marten to English moorland. Ground nesting birds and small mammals to name just two already have many predators and I think it will upset the balance of nature I believe some farmers are having problems with Beavers

I suppose I ought to be concerned. I tend to place my faith in scientific experts. At least I can be more like Dipsy, and ask questions.

MayBee70

For decades it was thought that animal populations were regulated by their food supply. This seemed reasonable enough but in fact in mature ecosystems the key controller is a top predator. Human beings are top, top predators, albeit hardly a part of nature any more, and they have very often removed the key predator from natural ecosystems with consequences we are only just discovering. Without top predators, herbivores run riot, consuming the vegetation. So in Yellowstone national park, Wyoming, healthy tree growth requires wolves to keep down the elk population (they eat tree seedlings). Off the Pacific coast of North America, without sea otters, the giant kelp beds are destroyed by sea urchins. In nature, though not in life, the adage “my enemy’s enemy is my friend” holds true. It isn’t only trees or kelp that benefit: when a top predator is established the number of species that can flourish is dramatically larger than when it is removed. Human beings generally destroy large mammals wherever they find them. We can now see that this has seriously impoverished our world. For Carroll, these revelations are grounded in his love affair with the Serengeti national park, Tanzania, where the greatest abundance of large mammals still flourishes.

I second that. Great post MayBee.

vegansrock

I wouldn't worry about grouse which are bred specifically to be shot for fun.

Here the can of worms opens, and not beneficial worms either. Land use by humans sorely needs to be reorganised so that grouse moors , landed estates, and other leisure pursuits of a few rich people are evenly distributed among all income groups.

Having said that, areas that raise birds to be shot ( and I’m not saying I agree with that) are safe havens for other wildlife. There’s some land owned by the Duke of Northumberland that doesn’t allow people to walk their dogs; I think it’s to protect the pheasants so he can shoot them. And I saw a programme once that showed some land where grouse were reared and a certain species of butterfly flourished there. I do worry about the wild boar in the New Forest as I think they’re quite dangerous ( going off at a tangent here but I listened to a History Extra podcast last night about reasons for people dying in the past and because people tended to share their homes with their livestock babies were often killed and eaten by pigs…).