Talk:Introduced species

Suggest merging with Invasive species; but having the contents here, as "introduced" is passive whereas "invasive" implys active invasion, which is not the case. Andy Mabbett 17:09, 9 Dec 2003 (UTC)

makes sense, although it will need bit of a rejig. Jim

I disagree. Most introduced species are quite benign. Invasive species are those that are serious pests or disruptions to the ecosystem - quite a different thing. I'll not put it back without more discussion, but I think the concepts are sufficiently different to merit separate pages. BTW "invasive" is an accepted term; this is not a POV thing. Millions of dollars are spent each year dealing with invasive species. Pollinator 04:52, 10 Dec 2003 (UTC)

would an alternative/additional idea be to have the conceptual content in one article and the list in another? I agree that "introduced" is better (more NPOV!) than "invasive", anyway. I'll do a search for unlinked occurrences of the phrase and add some links sometime. seglea 21:55, 9 Dec 2003 (UTC)

Hang on! we're cutting across each other. I'll go and do something else for a while and let you finish what you're doing. seglea 22:36, 9 Dec 2003 (UTC)

• Thanks. I'm done. Andy Mabbett 22:56, 9 Dec 2003 (UTC)

The more I think about this, the more I think it's a mistake. If you look at your garden, I betcha 80% of the species are "introduced." However, let me send you some kudzu seeds, so you will see what "invasive" really means! They are NOT the same thing.

I would agree. Introduced and invasive are not the same thing. Many species when introduced will spread very slowly if at all, and may not affect the ecosystem greatly. A very few species are incredibly successful at spreading through new territory (e.g. kudzu). WormRunner 05:58, 10 Dec 2003 (UTC)

I also agree, for what it's worth. As "introduced species" is a blanket term covering both invasives and non-invasives, this article's terminology and intro need a bit of a retouch, I think. There needs to be a more explicit distinction between the two "types" of exotics. As it stands the article gives the impression that all introduced species are harmful. But as long as the difference is clearly explained, I think both invasives and non-invasives can be discussed in the same conceptual article. After all, there's already a section on reintroduction.

The list should be kept separate as I believe an extensive list is of value. The list article should also contain a note differentiating the possible meanings behind "introduced species." Just my opinion- Hadal 06:53, 10 Dec 2003 (UTC)

We need to better define the terms, and perhaps redistribute the sections. In my mind "introduced species" and "invasive species" are NOT the same thing, although there is a movement in some places to simply lump them together, the idea being that "invasive" is a loaded word (therefore POV I guess). I think they can be distinguished and separate articles preparted for each. I will research/work on definitions as a point of departure for possibly restoring Invasive species - Marshman 17:34, 9 Jan 2004 (UTC)

Cultivated plants can be native or introduced. The introduced cultivated plants are not usually invasive, though kudzu comes to mind as a notable exception. Pollinator 19:38, 9 Jan 2004 (UTC)

Much as I would like to agree with you (and have included that concept in my rewrite), most definitions of "introduced species" that I could find exclude cultivated species by including the fact that a species is technically introduced only if it is also capable of propagating on its own in the wild. - Marshman 22:53, 9 Jan 2004 (UTC)

Exclusion of cultivated species from definition as 'introduced' is certainly not normal in Britain or other European countries; e.g. "Giant Sequoia was introduced to Britain in 1853" contains no suggestion of any need for naturalisation to be occurring (neither has the species shown any sign of doing so). All 'introduced' indicates is that the species is not native. - MPF 15:35, 25 Feb 2005 (UTC)

I am unaware of usage excluding cultivated plants from "introductions" - in fact, if you read the history of spread of cultivated species you see the term "introduced" repeatedly. As I know it (mostly based on used I have encountered in floras), introduced species can be:

• cultivated
• persistent after cultivation
• naturalised
• invasive

Guettarda 16:13, 25 Feb 2005 (UTC)

Invasive species are always introduced, but introduced species are rarely invasive

For what it's worth, I agree with the thoughts express recently by Pollinator, WormRunner, and Hadal. All invasive species are introduced, but not all introduced species are invasive; thus, the term introduced is not at all synonymous with invasive. An invasive species is simply an introduced species that has shown the ability to cause economic and ecological damage in its new environment. A very small percentage of introduced species ever reach the point that they could be considered invasive (i.e., damaging). The development and maintenance of domesticated plants (crops) and animals under the care of humans is largely unrelated to the establishment of introduced populations capable of sustaining and replacing themselves in a natural situation without the aid of humans. That's not to say that domesticated animals don't sometimes escape to the wild and establish self-sustaining populations (examples include wild horses in western U.S., red junglefowl [=chickens] in Hawaiian Islands, mute swans in eastern U.S., rock pigeons worldwide). Rather than clarifying the clear distinctions that most ecologists have long recognized between introduced and invasive species, I fear that Marshman's rewrite of the introductory paragraphs has simply muddied the waters further. In my opinion, there's definitely a need to retain a separate Invasive species page. John Trapp 20:11, 9 Jan 2004 (UTC)

I think you should reread my changes. I agree almost completely with what you are saying and would next propose that we reinstate the Invasive species article. However, I do think you have overstated the clarity of the most important point: whether a species is invasive or not (as opposed to just introduced, about which there is little to argue, except whether farm animals are or are not "introduced") is not so easy to judge since there must be agreement of harm. In Hawaii, better than 90% of all the lowland vegetation is non-native, and it is really a matter of serious debate whether all of these species have caused harm (most visitors and residents alike think the vegetation is beautiful; environmentalists, botanists, many native Hawaiians regard the vegetation as invasive without question). Because of the strong potential for disagreement, there is generally a movement (in the US if not worldwide) to define all as simply "introduced" and dump the word "invasive". I am proposing that "invasive" be all that you say it is, but include the regulatory component. Presumably, species listed by government agencies (or even NGOs) have been deemed to be officially harmful somewhere. This removes POV arguements that are likely to ensue. Further, it is consistent with sources of definitions, going against which would be to "muddy the waters" - Marshman 22:33, 9 Jan 2004 (UTC)

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The great majority of introductions have involved the transfer of European species to New World and Australasian countries by settlers; in some countries, Acclimatization Societies were set up, particularly in the late nineteenth century, to promote this process. However there have also been introductions between New World countries, and of New World species to Old World countries.

May we have source for this affirmation please ?

If I dare, that sounds to me like...a bit new world perspective. It is perhaps forgetting all the big travels made by navigators, who brought back many new species to Europe.

PomPom

Are you familiar with black locust, Robina pseudoacacia, an Appalachian tree that was introduced to France? It is the source of the famous French "acacia" honey. I expect it is naturalized, comment? 24.31.216.66 15:37, 10 Jan 2004 (UTC) Pollinator 17:59, 10 Jan 2004 (UTC)

terrible to discuss when watchlists are off. No, do not know it, but will ask to one of our french, who is spending all his time on the vegetal species articles. PomPom

w:fr:Jeffdelonge made it today :-) w:fr:Robinier. What does that exactly mean "naturalized" ? All I can say is that acacia honey is among the most consummed, and very appreciated. That little tree made it about in most of the country. Mostly west, but we find many around as well. In the west, it is often associated with sandy soils in particular. It does not go further north than our country. I think in some places it spreaded a lot, but we would not qualify it an invasive species :-) Apparently, it is very well adapted to our mild climate.

The term "naturalized" means that after an initial introduction, the species is able to spread on its own - Marshman 01:46, 17 Jan 2004 (UTC)

I also doubt the correctness of this statement and will remove it. Let us not forget the numerous species introduced from Asia to Europe in ancient times, including most cereal species, several herbs and spices, rhubarb and others. Let us not forget species introduced from the New World to the Old, including potatoes, tomatoes, maize, the rainbow trout, the raccoon and many others. Until someone can back it up with numbers, this sentence should disappear. Burschik 11:05, 27 Jul 2004 (UTC)

Yesterday, I saw a documentary about introduced species on TV. They claimed that there were more than 1400 introduced animal species in Germany alone. Burschik 09:21, 28 Jul 2004 (UTC)

Introduced plants

Algae are not plants; reference to Caulerpa as a plant is not strictly accurate even though common usage often lumps algae in with plants. Is it more important to maintain "familiar" usage for non-technical readers, or strict accuracy? Guettarda 23:52, 9 Dec 2004 (UTC)