Some of the points that Dr Kunte has made are quite significant. Invasion into
island ecosystems
is normal and in a sense essential as without invasion life on islands would die
out due to
inevitable (local) extinctions.

What is to be guarded against is "intentional" introduction by anthropogenic
interference as then
we may not know the impact - see for, example, the famous case of African bees
in the Americas.

We should push for a strict moratorium on any intentional introduction - be it
animal or plant
species.

My understanding of the elephant introduction was that all elephants were
actually feral and to
that extent such events would be sui generis
devi
----- Original Message -----
From: krushnamegh@...
To: andamanicobar@...
Sent: Tue, 22 Feb 2005 00:48:52 +0530
Subject: Re: [andamanicobar] weeds



i do not know why this email was sent, or what was the intention, but
i am struck by the lack of understanding of invasive species. i am
getting more concerned with the lowering quality of information on
some of these email groups, and this one about the islands and
invasive species is particularly distressing. the "information" about
"weeds" in this email seems particularly oblivious to the vast
literature that has accumulated over many decades, and particularly
in the last decade. i will give just a few examples:

>weed species (plant or animal)

they may be invasive, but you do not refer to animals as weeds!

>Lantana camara ... is found in Nagahole, Bandipur, Valparai,
>Bharatpur, KMTR, easter ghats, Andaman and Nicobar...

it is a very widespread exotic, do you mean it is restricted to only
these regions in india? or YOU have visited these areas and noticed
it there?

>What is the problem with these animals or plants?.... None of the
>changes are perceivable by you or I within a short period of even 5
>years.

there are a number of cases in which impact of invasives was
perceptible within a few years. anybody who has grown up in india and
have been outdoors will probably have a story to tell about one weed
or another.

>well they push out almost to extinction some other species, this is
>what we expect based on models.

not all exotics become weeds, and weeds may not have a significant
primary impact on the community. weeds would probably be more likely
and more dangerous where the habitat has been disturbed by human
activity and when the disturbance continues. whether the exotics
alone drive local flora and fauna to extinction, or whether
disturbance does the job, or whether invasives follow disturbance and
act synergistically, is debatable.

i also did not catch the significance of meandering on the looks of
invasives and ethics.

i do sympathize, however, with the concern over quarantine (or more
precisely, the lack of it) and totally agree that prevention is the
best way to go.

At 1:46 AM +0000 2/22/05, Shreyas wrote:
>The problem of species introductions is never easy to determine at the
>time of introduction, except by prevention.
>
>All over India and surely S.Asia we have many weed species. Most
>common are plants as they easily establish. weed species (plant or
>animal) tend to have a wide range of requirements and thus are easily
>established. Lantana camara is a weed plant, of S.American orgin I
>believe. This is found in Nagahole, Bandipur, Valparai, Bharatpur,
>KMTR, easter ghats, Andaman and Nicobar... Prosopis sp also from latin
>america - Bharatpur habitat is virtually replaced by this plant.
>many road side plants are obviously weedy, they need to disperse
>easily and thus establish where dipersers are most frequent
>
>What is the problem with these animals or plants?
>well they push out almost to extinction some other species, this is
>what we expect based on models. In many cases we do not know what is
>being excluded in this way. Or these organisms may alter some
>ecological process by eliminating some link or combination of those.
>None of the changes are perceivable by you or I within a short period
>of even 5 years.
>
>then we have the commensals. these are species that follow humans. the
>crow and common indian lizard are commensals. two species of geckos
>occur all teh way from Turkey tthru east asia into northamerica.
>
>not all exotics are invasive. invasives as i described above actively
>colonize.
>
>So again, what is the problem. When you go to Keoladeo National Park
>in Bharatpur and see a habitat matrix of lantana and prosopis, the lay
>person (including the wildlife administrator) is pleased to see the
>green leaves and thick vegetation that provides shade to the 'pretty'
>deer, berries for the 'pretty' birds and props and shade for the rock
>pythons. Thus many invasives win this battle just by looking good.
>
>On the west coast of great nicobar at Kopenheat- the only road to this
>beach fell off 5 years ago or earlier. but we still trekked across the
>island in 2001. at one place along the way we found tell tale signs of
>a former camp (police or forest) - there were ornamental plants. At
>kopenheat, when we thought we were lost in the forest we were relieved
>to see these exotics; we knew the forest camp could not be far away.
>
>that is how plants do it. they look pretty in addition to reproducing
>prolifically and dispersing .
>
>animals that are feathered or furry have the advantage of looking
>cute, pretty or beautiful. thus elephants and the deer in the islands.
> squirrels in portblair. These were conscious introductions. similarly
>the cute cats and cute dogs. these are teh worst enemies of island
>fauna. I love cats. If you would like to guess how i did my first
>collections on Great Nicobar, it was by stealing my cats food (PS the
>cat adopted me, not the otherway around).
>
>snakes are not fortunate as everyone fears them and they get hacked if
>found, but the nocturnal dwellers like pit vipers will remain
>undisturbed and stow away.
>
>frogs are poor dispersers and thus also ideal for studies of island
>biogeography.
>
>the law is only a part of the issue and is very dynamic and
>accomodative within its processing speeds. there is the preceived
>moralistic and ethical view that people subscribe to. thus shooting a
>dog is unacceptable. many times we have stopped short of having
>authorised extermination of dogs on turtle nesting beaches for fear of
>Maneka Gandhi and her likes. I was once in a PCCFs chamber when two of
>her cronies came to preach animal welfare. I was just returning from 6
>months on the Galathea, a turtle nesting beach . The PCCF mockingly
>listened to the PFA and gestured me to explain how cordial the dogs on
>the Galathea were. A very annoyed PCCF turned back to the PFA and
>asked them, 'do you want us to protect dogs or turtles'.
>
>here is another irony, the stray dogs and cats are allowed to kill
>indiscriminately. when a legitimate researcher asks for a small sample
>of even a dead animal on the road, the paper work is so enormous.
>
>
>when agricultural imports begin to these islands to re-establish
>agriculture, you will have many many weed species coming in. mostly
>they wil colonize the edges of roads etc... many microbial parasites
>of plants and animals may also come in. many new insects may come in.
>BUT all our focus is on the agriculture and people. these pests and
>weeds may affect some innocuous process in the forest that is neither
>the focus of the biologist or the administration.
>
>
>here is another story of species introductions - the lizard
>Coryphophylax, endemic to the andaman and nicobar islands has its
>southern limit half or one Km north of great nicobar on Kondul. I have
>a hypothesis - Kondul's population of this lizard must be less than
>100 years old. i.e. species introduction of island species, not even
>mainland species.
>
>I had an email from Manish on this issue yesterday. I asked him is
>there any sort of process in handling shipping goods - his reponse was
>that material goes on to the ships and off, with no quarantine.
>
>
>(RE: volunteers in the islands, I can only suggest if you see any
>reptile; get its photograph dead or alive. I should be able to tell
>you if that may be native, introduced or new! send pictures of other
>fauna also - http://biology.uta.edu/shreyas/specimens.htm )

--
Krushnamegh.

--------------------------------
Krushnamegh Kunte
Doctoral Student (Gilbert Labs).
University of Texas at Austin,
Section of Integrative Biology,
1 University Station C 0930,
Austin, Texas 78712-0253.

Office: (512) 471-4506
Cell: (512) 577-1370
Fax: (512) 471-3878
Email: krushnamegh@...






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