When I began to have an interest in Fauna & Flora of Cape York I was totally stumped as to how much of the vegetation is not indigenous. Even the offshore islands have plenty of introduced species. I put that down to early seafarers both indigenous & non-indigenous who planted vegetation for all sorts of reason, all with foresight for the long term. It is called evolution.

< Underlying the article, we see explicit or implicit assumptions of the environmental movement worldwide: that
• man is alien to nature
• man’s use of natural resources is immoral
• “proper” ecosystems are those without any human influence
• a proper role of government is to decide and implement which species belong where
• there was a Golden Age in which ecosystems were undisturbed by man
• nature is tending towards a perfect final form, making inexorable progress, tending ever upwards
• species extinctions are morally bad. >

Crikey Jardine, where do you get this end-of-the-spectrum assertion from?

As you say;

<< The article muses whether an ecosystem of species introduced by man to a bare island is bad or good… >>

… and I don’t see any conclusion that it is bad.

Fred Pearce is somewhat enamoured with the feral ecosystems on Ascension. So am I with some of those that I have encountered in north Queensland, and indeed all around the country.

So um… just where did you get these seven points above? They might apply to some peoples’ views but certainly not to this article!

<< I put that down to early seafarers both indigenous & non-indigenous who planted vegetation for all sorts of reason, all with foresight for the long term. >>

Indi, the weeds in your part of the world are due largely to accidental introductions of seeds and to some ornamental and otherwise useful species that have escaped highly humanised environments.

Particularly the Poaceae and Asteraceae (grass and daisy families) have a large number of weed species with this sort of history.

Ludwig,
I agree with your assertion & what I meant by long-term foresight was that vegetation was introduced to make barren places somewhat liveable by the shipwrecked & other unfortunate people who might be cast ashore on such barren shores. Yes, a lot of weeds come from plants which were introduced here because they made some settlers feel more at home. Of course most species introduced are fruit bearing. Both man & animals are designed by nature to be carriers for spreading vegetation. It's all part of evolution.

A really interesting article, thanks Fred Pearce.

A marvellous insight into a unique bio-system, and, concurrently, into the complexities of environmental or 'conservation' science - which is an area of increasing interest to bio-scientists, and to what might perhaps be termed bio-ethicists, as human populations and associated resources demand (and consumption) continue to soar to extraordinary levels.
The competition for space and 'habitat' is veering towards (or is already at) a breaking point in many regions and many contexts, with resultant 'contests' between environmental and human interests approaching crisis level.

Some would assert that relevant concern for 'environmental' interests may principally be confined to affluent westerners and various academics, but there is also long-standing and increasing recognition of the economic and cultural values of environmental conservation in many developing nations, particularly as the impacts of environment 'loss' become increasingly evident.

Given that 'conservation' has been a major component of the human survival 'mechanism' for eons, and at least up until population and other pressures pushed human demand beyond mere subsistence capacities, 'environmentalism' remains a fundamental innate trait of the 'human condition' - though many 'moderns' would dispute this, just as they might dispute having any relationship with agriculture, mining or industry - because they are 'divorced' from these in their 'ivory castles'.

JKJ may consider that 'human values' must be ethically and economically justified to have merit, but I would assert that not everything in this world can or should be reduced to dollars and cents. For some things, ethical or moral justification is sufficient.

In the end result, the most potentially hazardous 'weed' is homo sapiens, warranting detailed and cautious monitoring.

The only interests that matter are human interests. The "environment" does not have a value, or "interest" in itself. Without the existence of ourselves, does it really matter what happens with the environment? If we inadvertently cause a species to become extinct, and this extinction does not have any direct or indirect effect on human life, then what was the value of that species? What if we never knew it existed? What if it never even existed? You could argue that all life itself has a value, but if you exclude humans from the environment, then who decides the importance of competing lifeforms? Or is all life equally valuable?

I believe what Saltpetre claims to be "environmental interests" and "human interests" are the same thing. For example, the rationale for caring about the loss of huge numbers of bee's around the world isn't because we are sad about the loss of life, it is due to their role in pollination of our crops, and the impact this could have on our own lives. The difference in what we call "weeds" and what we call "crops" is a value judgment we make due to our own self interests. Some on this forum seem to think that humans exist outside of the environment, and that our value judgments are detrimental to other lifeforms. From my experience we function in exactly the same way as the rest of the lifeforms in our environment, promoting that which is beneficial to our existence, destroying or avoiding that which is detrimental to our existence, and adapting to which we can't control. Not only are we part of the environment, I am sure the extinction of the human race would bring a mass extinction of species that would dwarf any detrimental effects of our current existence. Think about that misanthropists.

That said, there are environmental arguments that make a fair point regarding short term gain vs long term benefits, as well as issues of sustainability (however you wish to define it). However these arguments are all made within the "human interests" framework I describe above.