indicator species

[John Trueman]

John Landolt asked for good examples of an"indicator species".  He also wrote:
        "Am I correct in my assumption that an "indicator species" is one
        closely tied to a fairly narrow ecological setting?  Is not an
        "indicator species" one that supposedly can be used to monitor the
        "health" of that ecological setting?"

It seems to me there are two very different concepts of indicator species
out there in the conservation literature.  One is a species the presence or
absence of which indicates some environmental condition: metals,
pesticides,  acidity, overclearing, compaction, temperature-shock, winter
frosts, etc.  There are plenty of that type of indicator, both positive and
negative.  The other is a species which indicates *biodiversity* per se:
ie, the presence of this species is correlated with the presence of (i)
lots of other, unrelated species or (ii) other species somehow judged to be
valuable, or endangered, or otherwise in need of some management.

I cannot think of any examples of the latter type of indicator, but it
seems that often indicators of the first type are mistaken for the second.

John Trueman.


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John Trueman
Bioinformatics Unit
Research School of Biological Sciences
Australian National University        -------------------------------
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