Silver Lining

Rhododendrons are not native to the UK (Victorians had a passion for importing plants), though are accepted as such. At the same time they are highly invasive, causing damage to rock faces and taking over from other plants. They fit the definition of a weed (something growing where you don't want it), though by that definition a rose could be a weed.

I agree that it's a judgement call, but is all life invasive ? Depends on whether you consider it to have evolved in primordial soup or arrived in some basic form from asteroids/comets.

Invasive seems to be a term for life that becomes a problem to existing species. Native is a lot more difficult. Either term is a bit awkward for people.

OP is making a good point, but I can't think of any cases where an invasive/non-native species has not bitten us in the ass.

My question is how much good were the native mussels doing?They also clogged pipes, and boats hulls,perhaps not as quickly,so the problem is the cost of more frequent cleaning.How much would it cost to build a filter plant to cleanup the great lakes,and operate it 24 seven?Could such a plant be possible?I doubt it. What harm does the Zebra mussel do in Europe?If it runs out of food,it will die, or the population will decrease,so it is self regulating.Some people hate them,but mother nature loves them.

I'd venture that control/eradication is impossible. They are considered invasive in the UK, but other invasives take the headlines so I'm not sure offhand as to problems

Self regulation applies, but it's a case of how much damage/over-poulation happens before that kicks in. Mother nature doesn't have emotions. Damn shame they are contaminated, I hear they are otherwise edible.

With the world wide pollution reaching all the way to the deepest parts of the ocean,and pole to pole,I doubt that there are any clean filter feeders left on the planet. I have given up oysters,scallops,clams,etc.but it probably won't make much difference.The entire food chain is contaminated bottom to top. We have lit a time delay fuse,and it is a matter of time before we have self regulated. Humans will either adapt to PCB's,radiation,high temperatures or we will become extinct. Only 1% of all species that have ever existed on Earth are still alive. We are in that 1%. One day some future or alien species will dig down and find a anthropological layer that will be the only trace of our existence.

One day some future or alien species will dig down and find a anthropological layer that will be the only trace of our existence."

Or maybe mechanical humanoids will dig us up and say "Look at this invasive species that came and went."

Earth has always had 'answers' for its new species. our universe is going from zero, to complex, and back to zero. Conscience has always (I believe) found a way to have entropy with all dimensions.

No silver lining....

The truth is we have had such spectacular disasters with introduced species that the caution can be misapplied, or people may believe that every "introduced species" is bad in every context. This is not necessarily the case, but there are good grounds to be careful on a case by case basis.

For example, where I live there were zero species on the land 10,000 years ago. On that time scale every species here is alien. It is also overall a very species-poor ecosystem, and depended on opportunities for a new species to (a)cross over from the mainland and (b) find the place habitable and (c) manage to persist without going locally extinct, in spite of a difficult and unpredictable climate. A new species that is invasive, ie puts others out of business and thus drives the system to a lower diversity state, is a danger. However the ecosystem does continue to welcome new species which arrive and become a part of it without causing imbalance. Squirrels, blue jays, coyotes, a few examples of new species in my lifetime that did not live here before. Of those three, coyotes are hunted and actively managed. Our native 'top predator' the wolf is extinct. Hares and moose, both introduced deliberately, have a negative impact on forest plant diversity unless the population is well managed too. And so on.

Some people are foolishly emotional about what is "native" vs "alien". The notion that we should or even could preserve what is presently 'native' by classic hands-off management (as in parks) is outdated or was never well suited here. There are imbalances, partly due to our own actions, and there is no way for this to have a good outcome without sound, pragmatic, and hands on management by humans. There is no 'self managing nature' that takes over when things are out of whack... you have to take responsibility.

SQUIRRELS !

OK, fair point, I'm jesting. The greys have decimated the indigenous reds. Human activity has crapped on the habitat anyway (and possibly to a greater extent).

I'm pondering if anybody can name an introduced species that has worked for the greater good.

A number of causes/organisations want to reintroduce species to the UK, on the basis that they lived here a few hundred years ago. An attempt in Scotland resulted in the beavers promptly scarpering. It's somewhat like Microsoft - we introduce a patch, then a patch for the patch, a patch for the patch for the patch....

Apparently the central dogma of conservation is being challenged on the books now:

https://e360.yale.edu/features/alien_species_reconsidered_finding_a_value_in_non-natives

https://listverse.com/2015/05/04/10-invasive-species-that-helped-the-ecosystems-they-inhabit/

That is besides the fact that a very small percentage of exotic or introduced species have the potential to become invasive. I suspect that invasiveness or dominance is not going to be a stable quality in a changing climate world.. we will always have to pay attention and be prepared to step in when imbalances emerge.

As for our new squirrels they aren't doing any serious harm that I'm aware of and seem to be filling an ecological role... preventing zucchini (courgettes) from running rampant in the boreal forest. And of course, providing comic relief.

Can't find a link now, but a fair while back UK Honey Bees were in severe difficulty (more so than now). Situation saved by importing bees that had previously been sent to New Zealand. They never went extinct here, so I'm not sure if they are properly indigenous or what !

Courgettes, as we Brits call them, are delicious when lightly fried in butter.

"Courgettes, as we Brits call them, are delicious when lightly fried in butter." Oddly I've heard the same thing said about squirrels.

Good point about getting back species and varieties that were being lost! I've heard a similar story about grape varieties that were wiped out in the place of origin. This can only become more common in the future. It is a good thing to share important crop and other species to distant places....

..."Research on natural enemies, both in Europe and North America, has focused on predators, particularly birds (36 species) and fish (15 and 38 species eating veligers and attached mussels).

The vast majority of the organisms that are natural enemies in Europe are not present in North America. Ecologically similar species do exist, but these species are unlikely to be able to eliminate those mussels already established and will have a limited role in their control. ^[14]

Crayfish could have a significant impact on the densities of 1- to 5-mm-long zebra mussels. An adult crayfish consumes around 105 zebra mussels every day, or about 6000 mussels in a season. Predation rates are significantly reduced at lower water temperatures. Fish do not seem to limit the densities of zebra mussels in European lakes. Smallmouth bass are a predator in the zebra mussels' adopted North American Great Lakes habitat.^[15] "....

..."Lake floor food supplies are enriched by zebra mussels as they filter pollution out of the water. This biomass becomes available to bottom-feeding species and to the fish that feed on them.^[9] The catch of yellow perch increased 5 fold after the invasion of zebra mussels into Lake St. Clair.^[10] "...

https://en.wikipedia.org/wiki/Zebra_mussel

The Lobster of the South...

I love Zebra Mussels for breakfast, lunch, and dinner...

The Cow Nose Skate has literally wiped out the scallop population on the Mid Atlantic coast due to their population explosion, because of the near elimination of their primary predator:The shark. Maybe the Cow Nose Skate will eat the Zebra Mussels? "I have a great idea! Why not bring in some of those giant Australian crayfish to help get rid of the mussels?.... " "Or some of those large Signal Crayfish from Oregon...." and so it goes,round and round....Cane toads,pythons,etc."

https://insider.si.edu/2016/04/cownose-rays-aquitted-not-guilty-decimating-chesapeake-oysters/

opinions vary: =============================================================================================================================================================https://ncseagrant.ncsu.edu/coastwatch/previous-issues/2009-2/holiday-2009/return-of-the-bay-scallops/--------------------------------------------

Europeans are an invasive species in North America and tropical paradises,like Hawaii.Small pox nearly wiped out the aboriginal peoples. The American Indian is almost now extinct. They have more right to complain than any minority group but their numbers are now so small they do not seem to matter politically. The loudest squeaking wheel gets the grease. Japan aboriginals had beards and blue eyes,and are now living in isolated communities,similar to a lot of aboriginal peoples all over the planet. And remember,humans invaded the world from Africa. Perhaps man himself is an invasive species,with no natural enemies except himself,the worst enemy of all. We have certainly damaged our environment to the detriment of all creatures,large and small. Perhaps we were banished to a remote isolated spot far enough away from the rest of the universal family to prevent our spread for a long time.Perhaps by the time we are able to travel among the stars,we will have matured enough to get along with other sentient species. But first we must learn to get along with ourselves. Imagine an alien child asking his father,"Why don't we ever land on Earth?" "Why do we only cruise by and never stop?" "Well,son,it's like this.They kill each other because of skin color,opinions,gender,religion.What do you think they would do with orange beings that did not look like them? "It will be many centuries before they are mature enough for a social call,if they survive." "Now turn on the light and get some sleep."

Yeah they probably think we're in a zombie war....

Seems I remember a Sc9-Fi series with one episode about that topic.

My father wanted a "privacy screen" so he planted bamboo.......

It took over, I have been killing it for 2 years now.

https://www.hgtv.com/outdoors/gardens/planting-and-maintenance/avoid-bamboo-like-the-plague

I found introduction of cattle into Argentina a good enrichment for the dinner table.

I agree.How about reintroduction of horses to North America?And domestic cattle of all types,and chickens,and potatoes carrots,and other important crops. Spiders travels thousands of miles riding the jet stream. Coconut trees sprout on islands thousands of mile from nearest land. The planet is a homogenized blend of all types of life,and the ones that are the most adaptable survive.This the basic law of nature. The life of the invaded country will adapt.It may not be as we wish,but we are not totally in charge..yet.

In the context of evolution, insects, birds and mammals emerged with (or for) flowering plants. While the primary role of insects was pollination, the basic ecological role of seed dispersal is ascribed to animals in general which the plants attracted for that purpose with their tasty and often brightly colored fruits.

The trinity of microbes, fungi and plants is sustainable on its own, but rich enough to sustain other life forms. Wind and water, yes, will take you so far, but a motivated moving creature is even better. Every animal co-evolved with plants that are its food, and (in general) played a role in dispersing them into new habitat as we roamed further from our origins. In the sense that we have a fundamental drive to nurture and protect our plant foods and medicines, and to bring them with us when our legs do travel, it is not at all surprising to see this happen.

It may have also helped bring us some chillin'.

Let us not forget the most insidious and evil of all invasive species, the cat...whose microbial infection of human brains has bent the will of mankind to live as slaves to the feline gods....

Destroy them all, before it's too late...!

http://www.chowmember.com/

Cat Haters Of the World

You are so right - I can speak as one of the infected. Put me out of my missery or bell the CaT! (SORRY FOR FORMAT- fIREFOX IS STILL MESSED UP. i'M ON THE VERGE OF DITCHING IT AND GOING CHROME.)