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Natives vs Exotics

Someone in the immigration thread mentioned the fundamental law of nature that says any forum discussion will eventually lead to a gratuitous Nazi reference.  Now the discussion is heading down the invasive species path and the combination reminded me of something I read in a JL Hudson seed catalog years ago.  I looked for it and, thankfully, the old man has gone online.  That's a little surprising, since I don't think he even had a telephone when I used to order from him.  Anyway, he has some opinions and this one kind of turns the whole native vs. exotic species discussion upside down - http://www.jlhudsonseeds.net/NativesVsExotics.htm
 
this could be an interesting discution. i will see how it starts before i interject a couple observations on "exotics" on a local basis
 
I try to plant natives wherever possible, and slowly my garden is becoming more and more native. I have tickseed, roesemallow, coneflower, beggar's ticks, beebalm, spiderwort, sunflower, aster, and a host of naive grasses in my garden. My perennials are 95% native. That being said, exotic annuals and perennials also have a place. I cannot imagine the place without cosmos, zinnias, daylilies, and whatever else i manage to pick up. Well-behaved exotics provide variety. And who could refuse a lilac's flagrance??

Exotics do not, however, belong in the wild, and much more extreme measures must be taked to reduce their cultivation in private gardens as well as controls in the wild. they are the 3rd biggest threat to the environment, and should be taken seriously
 
ok one clarification. when i think native i think "local native" as in native to NE Montana and the similar habitats within a reasonable distance and this is aplicable to where ever your at. main example i can think of is i grow bleeding hearts in my garden. they are native to the US but not NE Montana their for would that be an exotic? while im not 100% sure im assuming Finch your talkin "North American native"

mind calrifying for me which we will be discussing for this thread?
 
It'd be a nice essay...if he had any clue what he was talking about. The entire thing reeks of lack of understanding and simple lack of research.

First, the issue of dispersal and range expansions in nature vs those induced by man. In spite of the author's ill-informed claims to the opposite, there are three main differences: distance, speed, and continuity.

Natural range expansions are slow, short-distance, and continuous (at least in the sense that a species cannot colonize habitat farther away than an individual can travel). This can be due to a variety of factors, but it means that the new species come with some important hitch-hikers: parasites. These keep the new species from enjoying too much of an advantage. In contrast, human-induced range expansions are discontinuous, covering vast distances in short periods of time, and consequently breaking the life-cycle of any parasites the exotics carry, leaving them free of a major natural check.

Second, the consequences. Introduction of a new species will often cause extinction, and it doesn't matter whether humans or nature is responsible. Google "The Great American Interchange". When the Panama isthmus rose, it allowed large mammals from north and south america a chance to invade, and they did. When did you last see a litopteran or a toxodont? You haven't outside of a museum; this natural invasion wiped out much of south america's distinct fauna. Ecosystems recover and re-diversify, but the unique species lost will never be recovered.

Additionally, lumping 'exotic' with 'invasive' is fallacious. Not all exotics are invasive; some simply cannot meet the demands of the habitat, or reproduce, or manage to accumulate sufficient numbers. My boa is exotic, but could not be invasive; if he escaped, one Ohio winter would kill him. Additionally, few enough boas would escape in Ohio in any year that there could be no wild babies; the snakes would never find each other (though this is not always true, see the Burmese pythons in Florida). There are snapping turtles in the wild in England, and in good numbers, and they're breeding...but it never gets warm enough for the eggs, so they never hatch. Only some species can become invasive, and identifying these is an area of great current research.


The most egregious error of the essay, however, is the outright lie that invasive exotics have never caused problems. In australia, cane toads eat everything that moves, endangered or not, and have no predator that can withstand their toxins. In the USA, zebra mussels choke out native species, replacing the diversity of many species with a single one.

This is also something I have direct personal experience with, as I conducted fieldwork last summer on an invasive species in Guam, the brown tree snake.

For those unfamiliar, Guam is a small pacific island in the middle of nowhere. Like most such islands, it had a wide variety of amazing birds. A few introduced species showed up with the polynesian colonists, and a few more from the Spaniards who took it over. Then, in WW2, Japan took it over. Eventually, the US won it back and, due to the location, established major naval and air bases there (to this day, the entire northern 3rd of the island is Anderson AFB). And that's where the trouble started.

Sometime around 1950, several brown tree snakes (Boiga irregularis) stowed away in cargo containers and arrived in Guam. This is a species of mildly-venomous, constricting snake which is an excellent climber, swimmer and crawler, can reach over 10 feet long, and reproduces extremely rapidly. By 1970, the island's bird population (which had evolved in the absence of snakes, and thus did not have any aversion to them as predators) was in free-fall. By the 90's, almost a dozen species of birds had been eliminated from the island, some now extinct in the wild as a result. Faced with a lack of food, the snakes began turning to the lizards and anything else. Large adults have snuck into houses and attempted to kill and eat *human* babies. They climb into powerline transformers, causing island-wide blackouts to the cost of millions of dollars.

From personal obervations: I've caught snakes in florida and the amazon, and *nowhere* had abundances like Guam. In the Amazon the entire group found a dozen snakes in a week. In Guam, I found 15 in *two hours* just walking along the side of the road with a headlamp. I literally almost tripped over one. (The offical estimate of their density is 14,000 snakes per square mile. 14,000!) And there are almost *NO* birds. Even the marine birds are infrequent, and if you don't count those, I saw 6 birds in 3 weeks (two sparrows, a pigeon, and 3 of a native crow).

A formerly complex and diverse ecosystem has been reduced to a handful of species, almost all of which are eaten by this snake.

Oh, but wait, there's more!

You know Hawaii? Think it'd be a nice place to visit, with pretty tropical birds and plants to see? Go there soon, because it'll be like Guam within 50 years. Guam is a major air and sea hub to Hawaii, and the snakes aren't content to stay in Guam. They've been found in boxes in Hawaii, the Phillipines, Japan, Texas, and *Spain*. The snake-sniffing dogs recently found one in a box that had been on Guam for 15 minutes, and most boxes don't get inspected. If they get to Hawaii, you can kiss every bird species there goodbye, along with all the plants they polinate and disperse the seeds of.

Will the ecosystem fix itself over time? Sure. But in the meantime, we severely damaged it through carelessness. And nothing will ever bring those species back. Not to mention the economic costs. How popular do you think Hawaii will be when it's covered in 10-foot, aggressive, mildly-venomous snakes?

The entire essay you linked to is nothing but one man with an axe to grind undergoing excruciating logical contortions in a vain effort to make his perspective seem supported.

Many years ago, the modern environmental movement was kicked into gear with the publication of 'Silent Spring'. This book laid out evidence that pollution, especially with insecticides, was destroying the bird and amphibian populations, and if unchecked, it would lead to a 'Silent Spring'.

I've stood in the forests of Guam, with nothing but nature for miles, and heard that horrible silence. Such is the power of invasive species, more than our most toxic chemicals.

Mokele
 
but animal/plant extinctions are a normal part of the eb and flow of the planet. yes i realize man has sped this up to an extent(but not an extent never seen before, there have been a number of greater extintions in "pre-history") but eventually something will cause another mass extinction. whats to say man is not just going to be the cause of the most recent instead of an asteroid or other natural disaster
 
[b said:
Quote[/b] ] I've caught snakes in florida and the amazon, and *nowhere* had abundances like Guam. In the Amazon the entire group found a dozen snakes in a week. In Guam, I found 15 in *two hours* just walking along the side of the road with a headlamp.

ypu ever road hunted for snakes? i can do 15 in an hour on a really good night
smile_n_32.gif
 
On the link, it is as absurd as it claims the hurt that these things are doing for the variety.

Here in the plains states, in most areas native grasses and forbs are rare, being replaced with a monoculture of smooth brome. I once had a meadow planting a few years back with native grasses. Then smooth brome came, and i ignored it. BIG mistake. Within a matter of years it crowded out every forb and grass except some well-established clumps. It so completely ruined it that i had to remove it. This grass has done the same thing to native prairies.
[b said:
Quote[/b] ] is there evidence that man's introduction of species into new habitats has any negative impact on global biological diversity. On the contrary, the aid we have given species in their movement around the world has served to increase both global and local diversity

This is bull as the exotics do NOT carry their following of insects that feed on it. MOST exotics have very few insect pests that arrived with them. Naive plants have that. The insects that cant feed on the exotics go with the plants they crowd out. It is fact that a stand of introduced plants has on average 50% fewer insect species

[b said:
Quote[/b] ]New species create niches for more species, further increasing potential diversity
New niches yes, but removing nore than they create.




The real problem with this article is it is looking at the idea of a one-dimensional idea of total species numbers, relative to species diversity and abundance in alean modified habitats.


I also see that this person cites no scientific sources to back up his claim... I would like to see where he gets his, uh, “information”
 
If that's the attitude, why not just pave over the planet, kill any species we want, and not care?

Like it or not, we are dependent upon the ecosystem, and if it starts to fail, we can wind up in some serious trouble. Guam's tourist industry is dead, and the economy is in free-fall. Florida's gonna have trouble when the pythons and iguanas become more troublesome and numerous. Lampreys have ruined the Great Lakes fisheries, putting hundreds or thousands of people out of work, cutting off a long-running industry, and losing millions of dollars from the economy. Invasive insects can decimate crops.

Mass extinctions are *not* fun; if we cause one, we'll suffer for it.

And remember, the species vanishing can be vital parts of nature; producers, pollinators, seed-dsipersers, parasites, etc. Not to mention being useful to us; medical cures are being discovered regularly from animals and plants. How much would it suck to hear the announcement that we found the cure to cancer, except we just killed off the species that provided it?

Mokele
 
  • #10
[b said:
Quote[/b] ]ypu ever road hunted for snakes? i can do 15 in an hour on a really good night

On a good night, in a car. This was on foot on a random night, and we got a pretty light yeild; often they'll get 50 in two hours with just a few parties.

Mokele
 
  • #11
[b said:
Quote[/b] ]whats to say man is not just going to be the cause of the most recent instead of an asteroid or other natural disaster

Whats to say those natural disastes wnt happen during the disaster man is causing and making a double-whammy?
 
  • #12
[b said:
Quote[/b] ]On a good night, in a car. This was on foot on a random night, and we got a pretty light yeild; often they'll get 50 in two hours with just a few parties.
Spotlight for the reflective eyes and you'll see alot more.


Did you notice an unusual abundance of spiders on guam? I hear with the lack of pradators around they are overabundant now
 
  • #13
im not saying its right, not saying we wont pay for it if it happens. i just cant see any way around it being inevitable as long as we are around like we currently are.

as far as the prairies around here there isnt a huge problem, still lots of native plants, the none native tall grasses anf forbes arent choking out our low grow cacti(and i mean LOW growin)

BTW as far as "the cure for cancer" it doesnt exist, cancer is not just "cancer" its abnormal cells, and different types can be way to different for the same drug to work on all. it should be "cures for cancers" if you want to get technical.

Homo sapiens are a greedy distructive species. we are a plauge. you think the US industrial revolution caused lots of damage? guess what? China is wanting to be the next USA.
 
  • #14
[b said:
Quote[/b] ]Whats to say those natural disastes wnt happen during the disaster man is causing and making a double-whammy?

than things will start all over again, if its a double whammy, we more than likely wont be around to see what happens
 
  • #15
that doesnt mean we shouldnt care
 
  • #16
[b said:
Quote[/b] ]as far as the prairies around here there isnt a huge problem, still lots of native plants, the none native tall grasses anf forbes arent choking out our low grow cacti(and i mean LOW growin)

Smooth brome is more of a tall and midgrass prarie problem, not so much as a plant that shades its compeditors out but one th apoisons tham and takes over as the compeditors are weakened, reating a monoculture (sometimes, big established switchgrass clumps seem to be able to lolf their own)
 
  • #17
on a purely scientific basis, this guy lacks any merit.  "there are...many cases"?  how about some data, controlled experiments, references, PROOF?

there is a HUGE difference between a few lucky individuals making it to a new environment and surviving, let alone reproducing and establishing a population, and large-scale human-driven introduction of non-natives.  the migration events he talks about were not constant, large-scale events.  these were random events that happened very rarely.

ecosystems in their natural pre-human state have evolved a relatively constant state of checks and balances.  whenever a new species is introduced and becomes established, it lacks that natural balance that it would normally get from other species.  sure, it probably won't become a full-blown invasive, but since it's so unpredictable, why take that chance?  it could take a million years of evolution before everything's back in balance again.  why would anyone want to intentionally tamper with that beautiful, delicate order of things?  
confused.gif


oh, and his major criticism of anti-exotic groups is that they're funded by herbicide companies.  what a hypocrite...he's trying to sell exotic seeds!
 
  • #18
dont see how i would matter if it did?

as a highly active hunter and angler i am very pro conservation. however i know what man kind is. all you who want to make a difference i applaud you and will roll up my sleeves and help but in the greater scheme of things what is it really going to do?

i seem to remember thousands of dollars being put into a couple of seals that were rescued from the exxon oil spil up in AK. as the press wached and cheered as the rehabed seals swam away to enjoy a long healthy life in the wild affter all this money was spent getting them better a couple orca decided they were fast food and had them for lunch.

should have let the seals die from the oil and purchased more land to be set aside from logging, would have been a wiser investment but it doesnt look as good as releasing a couple seals and ppl get a national pat on the back where signing over a cople hundred acres might have got mentioned in the regional paper. ppl are greedy and its not always money they are after
 
  • #19
[b said:
Quote[/b] ]i seem to remember thousands of dollars being put into a couple of seals that were rescued from the exxon oil spil up in AK. as the press wached and cheered as the rehabed seals swam away to enjoy a long healthy life in the wild affter all this money was spent getting them better a couple orca decided they were fast food and had them for lunch.

should have let the seals die from the oil and purchased more land to be set aside from logging, would have been a wiser investment but it doesnt look as good as releasing a couple seals and ppl get a national pat on the back where signing over a cople hundred acres might have got mentioned in the regional paper. ppl are greedy and its not always money they are after


Agreed.

Those conservation stuff with charisma and media attention get all the money.

just like humanitarian crises. Who here knows about the crisis in Ungada? It is 'out of vouge' in the media right now, so few have heard of it. Dafur get all the attention and money.
 
  • #20
BTW Finch yah never answered my question. whe you say your growin "native species" do you mean "local natives" or "North American natives"

just curious more than anything
 
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