> > Obviously you percieve a problem here with how "scientists" conduct their
> > research relative to the numbers of specimens retained. On what basis do
> > you make that judgement? How many specimens are sufficient? I want to
> > understand your logic behind that statement.
> >
> How many specimens are sufficient?
I just asked you that question. :-) Maybe we'll have to start
calling you Polly Parrot or something like.....
It depends upon where, why, and what already exists. Many parts of
Australia have very limited specimen collections. This is a major
hinderance to taxonomic and distributional studies. For distributional
studies you only need a few speciemens, say 6. For taxonomy it depends,
in my mind ideally you want say 30 specimens of a reasonable size from a
location. But, then it gets complicated, small specimens are not very
good for taxonomic work and often species vary between the sexes (it
depends though on what characters you are examining). Ideally, you need
some large series of like 100-200 fish of various sizes from the same time
and place to get an accurate idea of how variation changes with age and
sex (this is critical with rainbowfishes). For instance, it may be that
fish under 30mm cannot be distinguished morphologically (I think Jerry's
preferred size for splendidas is 50mm). You don't need many collections
of this size, but it is important to have some. Of course though, if you
want to determine if populations have changed over time you'll need
repeated samples of this size, firstly to be able to find a difference,
and secondly due to statistical requirements. Few people worry about
this though but it could be informative. For genetic work it depends
upon what you are doing, for populations studies 30 is required as a
minumum, for phylogenetic studies using DNA 2-5 is ok. The whole
difficulty in this lies partly in statistical requirements and also in
sampling the variation that is present within the populations being
studied. With small sample sizes you just don't get the variation and
hence your conclusions are not well grounded. The other problem is field
work is difficult and expensive. When you get the opportunity you get as
much as you can (within reason as talked about above) from as many places
as you can. One must realise too that I am talking about common species,
when you get into rare species other things come into consideration. I
don't think heading out to some river in the Gulf of Carpentaria and
removing several hundred fishes really makes any difference in the grand
scheme of things. Until we have larger broader specimen collections there
are more benefits to be gained than lost.
This is a regular area of contention and misconception between scientists
and fishkeepers. I would be more than happy to explain the above in more
detail to anyone who doesn't understand, or disagrees with what I have
said above.
> Is there a set of guidelines available
> for scientific collectors to follow as agreed on by their various "august"
> representative bodies?
Not as far as I am aware. Different states have different guidelines and
in part it depends upon who is in charge of it at the time.
> I assume that NANFA and NFA and all the other
> exemplary bodies have theirs available and regularly published to remind
> members and observers.
Not as far as I am aware. NFA is pretty much static last I knew. NFA
ensures it has sufficent suitable fish for display purposes (it attends
one or more shows each year) often with a few young fish being raised up
for this purpose. In terms of it's breeding program with trout cod there
are strict conditions placed on obtaining more fish as they are fully
protected. I don't know if NFA has tried to get a permit to add fish to
it's program or not. It's only a small group with a handful of members,
those who are active are normally very active.
> In Australia at least some states have regulations
> about numbers allowed to be collected by amateurs as well as methods
> permitted.
As far as I know most southern states don't even consider aquarists
collecting fish in the regulations. They are just bait and last I knew
in Victoria there is no limit on baitfish. Of course, there are several
species that are illegal to keep in Victoria and South Australia now due
to their threatened status.
> I understand permits to collect larger numbers for scientific
> purposes can be applied for. But do the scientific fraternity have an
> attitude on this aspect that is well publicised?
Nope. Not that I'm aware of.
Tootles
Peter Unmack