Re-establishing the natural balance - UK

[Toddy]

From the BBC Scotland website.
http://www.bbc.co.uk/news/science-environment-43308588

The growing numbers of pine martens have actually helped the red squirrel population because the martens seem to take out more of the grey squirrels, which did not evolve alongside cat sized, tree climbing predators.
The Reds did, and seem to manage despite the pine martens, while the greys, which are much more likely to ground forage too, are predated upon and their numbers are reduced where the martens are thriving.

Interesting, and unexpected results

M

 

[daveO]

I read some theories a while ago that this might happen and at the time it was more hope than fact so this is a really good sign. Otters have really bounced back and I'm seeing quite a few polecat (maybe ferret) roadkills these days too.

 

[Toddy]

That's another good point there

One of the local countryside rangers was telling me that when the otters come back, the mink become land based rather than hunting along the riversides. This lets things like the watervoles and the wildfowl thrive again. The otters eat the signal crayfish, etc., and because they're on the land, the mink, another incomer pest, are more vulnerable to aerial predators, as well as cats, foxes and cars and their numbers decline quite sharply.

M

 

[Macaroon]

I hardly ever come accross signs of mink anymore, and even eight to ten years ago we were inundated with them; the downside to that is that the rat population has moved to take over the territory the mink occupied

We have, in the Wye Valley, also seen a huge resurgence in true polecat populations and I hope that they'll start to make inroads into the rat numbers. I, and a local vet who has a bit of woodland nearby, am convinced that we're also seeing signs of sparse but definite pine marten activity; we've just got some cameras to dot around his patch, hopefully we'll see visual evidence of them in the spring and early summer, but they really are elusive and highly intelligent creatures. All the signs are there, though.

I think most now accept that the reintroduction of the otter has had a profound and beneficial effect on the regional fauna, it seems the Wye now has, or is close to having, the ideal sustainable population of them so they should start to permeate more inland via. the Monnow and other small tributaries...............Happy days

 

[Toddy]

Sounds good

I don't see why more rats aren't caught and eaten by things like foxes though.

Maybe we need Pratchett type dwarves

The palaeontologists say that the ancestor of the mammals that thrived and eventually evolved into us, after the dinosaurs, was a creature much like a small rat.

Kind of worrying if one thinks on it too long.

M

 

[Broch]

The palaeontologists say that the ancestor of the mammals that thrived and eventually evolved into us, after the dinosaurs, was a creature much like a small rat.

M

I know some people that don't seem to have evolved at all

Other than badgers we rarely see mustelids here which is a shame. Very, very rarely do we see stoat or weasel and only once (in 24 years) seen a polecat on our patch.

Great news about the reds though

 

[daveO]

I think most now accept that the reintroduction of the otter has had a profound and beneficial effect on the regional fauna, it seems the Wye now has, or is close to having, the ideal sustainable population of them so they should start to permeate more inland via. the Monnow and other small tributaries...............Happy days

The otters I've seen were on the limits of a tributary of the river Usk and there's spraint all along the Monmouthshire/Brecon canal now. I have a theory that signal crayfish will actually become a very useful food source in helping the otters spread out which is mirroring the grey squirrel and pine martin story. I've been trying to find an otter latrine on my local river to see what they're eating up there but it gets flooded too often.

 

[Broch]

The trouble is they really are quite cute and have a certain 'attitude' that I admire!
They taste good too

 

[Toddy]

They are indeed. I'm watching two right now. They're hanging off the pole on the bird feeder pulling the seed cages towards them. They've discovered that if they do that, and rattle them about a bit, it doesn't matter that the cages are 'squirrel proof' because stuff will shake out
Then in come the big wood pigeons to help guzzle up the fallen bounty.

I wish I were as athletic as the squirrels

M

 

[Janne]

Great news. Britain will never get rid of the Greys completely, of course, but this gives the Reds a chance.

British nature has been so severely damaged over the past Millennia, like all across most of Europe, new like this are a joy to read!

 

[santaman2000]

....I wish I were as athletic as the squirrels

M

Don't we all?

 

[daveO]

Don't we all?

I dunno. Something tells me I'd be better off being as athletic as a pine martin.

 

[Toddy]

Oh good point

 

[Robson Valley]

It's an Arms Race = Predator and Prey. I don't think you would be at all surprised to see just how similar their skeletons are.
Prey are not extinct. Predators cannot kill them all. In fact, ecosystem studies commonly show that the predators get about 10% of the prey.
Yes there are a few aquatic exceptions of far greater efficiencies which can be ignored in terrestrial circumstances.

 

[Macaroon]

It's an Arms Race = Predator and Prey. I don't think you would be at all surprised to see just how similar their skeletons are.
Prey are not extinct. Predators cannot kill them all. In fact, ecosystem studies commonly show that the predators get about 10% of the prey.
Yes there are a few aquatic exceptions of far greater efficiencies which can be ignored in terrestrial circumstances.

The predator, in his taking of the ten per cent, will change the behaviour of the prey to an extent where other predators find it easier to get at them, and so on it goes...................

 

[daveO]

Well 10% is the success rate for hunting for the average predator as in when they try to catch something they only succeed 10% of the time. 100% of prey gets killed eventually due to age or weakness. The arms race can be physical but it can also just come down to how fast the prey can breed. If you see a bird that can live for 4 years having 10 chicks every year with no change in population numbers then that gives you a good idea of survival rates for the chicks.

Grey squirrels strike me as being quite a lazy species in this country now especially in urban areas. Hopefully the increase in predators like pine martins and goshawks that can hunt them in the trees will perk them up a bit.

 

[Toddy]

Well 10% is the success rate for hunting for the average predator as in when they try to catch something they only succeed 10% of the time. 100% of prey gets killed eventually due to age or weakness. The arms race can be physical but it can also just come down to how fast the prey can breed. If you see a bird that can live for 4 years having 10 chicks every year with no change in population numbers then that gives you a good idea of survival rates for the chicks.

Grey squirrels strike me as being quite a lazy species in this country now especially in urban areas. Hopefully the increase in predators like pine martins and goshawks that can hunt them in the trees will perk them up a bit.

I think so too. Thing is though, that urban parks and Goshawks vs Squirrels isn't going to go down well It's bad enough when it's Sparrow Hawk vs Pigeon.

 

[daveO]

I think so too. Thing is though, that urban parks and Goshawks vs Squirrels isn't going to go down well It's bad enough when it's Sparrow Hawk vs Pigeon.

Who wouldn't appreciate an awesome bird like that though Apparently in Germany Goshawks are really common in cities so it might not be too much of a stretch to get them back here eventually. I know a few local pigeon breeders who are less than happy about the prospect and already have problems with the peregrines that are doing really well around here now. The suggested solutions always seems to be to reduce the predator numbers rather than boost the prey numbers and available habitat though.

 

[Broch]

Who wouldn't appreciate an awesome bird like that though Apparently in Germany Goshawks are really common in cities so it might not be too much of a stretch to get them back here eventually. I know a few local pigeon breeders who are less than happy about the prospect and already have problems with the peregrines that are doing really well around here now. The suggested solutions always seems to be to reduce the predator numbers rather than boost the prey numbers and available habitat though.

I'd breed pigeons just to see the peregrines and goshawks

 

[daveO]

I'd breed pigeons just to see the peregrines and goshawks

I encourage wood pigeons into my garden just because there's a peregrine nesting site about a mile up the hill and one day I might get lucky. I think I've made them too fat for the sparrowhawks to tackle now though