Is It Native?

[Highland Damsel]

The question of which species are native or not native is a complicated one and some species we may not and may never know for sure - and is also really facinating. I read an article recently where it was suggested that non native species could be considered for planting schemes. Really? Another interesting question! (Don't think the idea would catch on though)

There is a difference between non native species and invasive non native species and whatever the arguments about the former, in plant terms where a species is invasive and creates a monoculture and continually extends its range, replacing whole systems then this must be taken seriously.

As to the benefits of Japanese knotweed, having spent days in deep dense stands of the stuff and seeing next to no evidence of any species diversity plant, animal or invertebrate, to say that stands provide shelter in winter and to extrapolate that and say we should cease control is slightly... surprising. A reed bed does the same thing without the expense of a habitat, usable land and the possibility of damage to property and infrastructure.

I don't know if we are right to favour native species or not but we do need to protect them from damage from those that are able to destroy, infect or just replace them.

[The Woodman]

I totally agree with your final paragraph, Highland Damsel.

"I don't know if we are right to favour native species or not but we do need to protect them from damage from those that are able to destroy, infect or just replace them."

[valleyforge]

Originally Posted by The Woodman

"whilst the favoured conifer habitat of the reds continues to be eroded faster than it is replaced."

Is this really the case valleyforge or is it the way modern forestry practice works with shorter cycle rotational coupes giving the illusion that areas of trees are taken away, but are being replanted continuously.

What I had in mind Woodman, wasn't so much the effect or otherwise within large scale commercial plantations, but the diminishing of current habitats around existing conurbations.

Populations of reds have often become 'pocketed' or isolated from each other, because development removes the corridors along which they would have once moved.

[Fritillary]

I dont think it is complicated to define native or not. Native is when the species has arrived since prehistorical times and forms part of the actual dynamic of the community.

If the species arrived since long time ago 2000-500 hundreds years with humans and it is living in the community without being a problem, it is said to be a naturalised species.

But if the species arrived since few years ago and now the populations are increasing in a explosive way, this is catalogued as Invasive. Also there are native that can become invasive because of human intervention. Humans destroy a stable community so, some species will increase their number because of absence of mechanism that control natality and survival.

UK as an island, has received lot of new species, First it was connected to Europe, it was a free pass, later when it became an island, the people that arrived brought lot of species with them. Romans for example.

The technological advances have increased the problem. First the ships during the XVI-XVIII century, bringing new species to zoo and botanical garden and later in the past century, product of marketing.

I studied S. inaequidens, a similar species to the commun ragwort and the first introductions from Africa to Europe (even UK) were because of transportation of wool. Nobody even knew they were bringing a plant with them. In Europe, wool was washed and people spread the water on cultures and fields in general, so seeds were release to the humid ground, perfect for germination. After some years the plants were happily established and now they are also a problem.

Any species has the potential of become invasive, native or not, if they live in optimal conditions. I think that if red squirrels had not been chased as vermin, they would be also a problem, like the grey squirels now.

[Highland Damsel]

Many species that are out of balance with human economic activities are considered to be problem species, native or not. There does recently seem to be a figure of eight cycle whereby we persue something to near extinction then sit up and realise and then protect it. This can lead to a population growth and in time to calls for control to be allowed again. This has happened with seals, is happening with badgers, raptors etc. Some will and do carry out illegal control and it is usually to protect commercial activities. At least groups exsist now fight and put forward arguments for many species. This didn't hapen in the 19th centurary whic is why species have been lost completely ans in some respects why we have some of the problems we do with non natives

[eeyore]

the grey vs red thing has already been done to death and i'm reluctant to go there again - but the overlooked point here is that it is not about competition per se but because the grey carries the parapox virus to which the red has no imunity.

If they could come up with a workable orally administered parapox vacine for the red the two species could share habitat - but at the moment there isnt a workable vacine

you can see the problem in action at formby point where their used to be a red popultion - then some chucklehead introduced a single grey squirel and zap, two years later hardly any reds.

the issue with reds being controlled also isnt as easy ass portayed here - to get a licence to control a protected species you have to demonstrate that significant economic damage is being caused, and that all practicable non lethal methods (in this case sacrifical crops etc) have been tried first.

given that the bottom has dropped out of the confier market anyway it would be almost impossible to demonstrate that minor bark stripping by reds was causing significant loss, and i'm not aware of any forestry commision site that is carrying out red control.