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Discussion

PULLIN: The lesson of history so far is that it is not
poasible to control fish transfers effectively whatever
laws and regulations are made. The private sector
especially, in dcvclopcd and developing countries,
usually finds a way to transfer or introduce fish
irrespective of policy and regulations. I don't think
this will change much. In fact, it may get worse. So, we
have tolive withthis andconsiderhow bestto conserve
fishgenoticdiversity. This paperclearly pointsoutthe
insitu andexsitu approaches. For in situ consewation
in natural habitats, however, we have to mnsider
what is practically and politically possible. I recently
wmte on this in Naga, the ICLAFtM QuarterlyL.
Conservation oflarge natural fishspecies assemblages
in large natural waterbodics will become increasingly
difficult as aquaculture grows. By analogy,
conservation ofnatural plant successionis also difirult
adjacent to intensive agriculture. What can work is
giving more attention to conservation of all aquatic
biota, including fish, in nature reserves and game
parks andinsmall waterbodies that are sitesofspecial
scientific interest. Of course, some large waterbodies
and their fish fauna are unique and very important
and all possible cfforts should be made to conserve and
pmte~t them fmm all potentially harmful disturbances,
including harmlbl efkts Imm aquaculture. This will
probably requirc lransnationnl agreements andthcir
enforcement. Good examples are Lake Mala% and
Lake Tanganyika.

ROSENTHAL: ~lthough ncccssary, transnational

control is not easy to achieve. In order to reduce risks

it will be necessary to stimulate more awareness

among farmers and traders on risks associated with

transfers and introductions. In other words, the

introductionofany reyllatorymeasure willhave to be

accompanied by an adequate educational program to

achieve the required acceptability of those measures

by practitioners ol aquaculture.

BILIO: We will have to learn how to cope with future

fish transfers irrespective ofregulations. We will have

to do our bestto anticipate their effects. Conservation

of aquatic genetic diversity needs an overall long-term

plan, remgnizing where it is realistic or unrealistic to

even try.

EDWARDS: I even have to watch some of the

aquaculture faculty at AIT over plans for fish

introductions - never mind the private sectorl

PULLIN: Do you want: that on mcord?

EDWARDS: Yes, I do, because it illustrates the

mmplexity of the problem.

BILIO: Expert advice on introductions needs very

close examination. In some culture-based fisheries

projects, expcrts have recommended introduction of

exotic species, like grass carp, to increase production.

Often introductions are unsuccesful. For example, in

Albania, introduction of exotic carps to supplement

mrnmoncarp production has beenuscless bccause the

exotics are not wanted by mnsumers.

PUELIN: ICLARM has had one workshop on tilapia

genctic resources2 andis planning another on Asiatic

carps in collaboration with the Asian WetlandBureau

and WCN. We know from our Chinese colleagues that

the wildgenetic resources of Chinese carps are under

threat.

lPullin, R.S.V. 1990. Down-to-earth thoughts on

conserving aquatic genetic diversity. Naga,

ICLARM Q. 13(1):5-8.

2Pullin, B.S.V. Editor. 1988. Tilapia genetic resources

for aquaculture. ICLARM Conf. Froc. 16,124 p.