News From Our Kenyan Funded Project
INCREASE THE FISH AVAILABILITY FOR BOTH OTTERS AND HUMANS
Introduction
Research over the last three years has shown that the diet of otters is an
accurate indicator of the state of the aquatic fauna in Lake Victoria and this
is therefore a cheap and useful tool for monitoring this ecosystem.
The effects of the Nile Perch (Lates
niloticus) on the cichlid fish fauna of Lake Victoria is well documented,
although its impacts on other piscivorous fauna and human fish consumers are
less known. The spotted necked
otter (Lutra maculicollis) is a key
predator in the inshore and littoral zones, where the communities are dominated
bycichlids.
This zone is also the mainstay of subsistence fishermen, i.e. those who cannot
access deep-water fisheries due to their inability to afford fishing boats or
larger fishing nets.
The Problem
Research in Kisumu has found that adult perch and otters compete for the same
size-class of fish (8-10 cm) in deeper water.
This has led to increased direct competition between otters and fishermen
for fish resources in the inshore and littoral zones.
This competition is revealed in the
declining fish catch (Perth: 6.5%
per annum, Tilapia: 10% per annum)
and rising market price for fish (Perth 55% per annum, Tilapia:
50% per annum) over the last six years.
It is also illustrated by the increase in “net-raiding” by otters and the
rising percentage of crab (Potamonautes
niloticus) in the otters’ diet.
There are also severe socio-economic and human health impacts, which are still
being researched by different groups.
The Solution
Clearly it is necessary for both otters and humans to survive alongside each other and to be able to obtain sufficient fish for their own consumption and to support a sustainable economy. In order to do this it is proposed to set up a trial programme of aquaculture which is operated by the local community.
This will provide an income for the community, a source of fish for their own
consumption and a source of fish for the otters.
It will reduce the competition between otters and humans and can indeed
provide extra income to the community through eco-tourism to see the otters and
other wildlife.
The community at Kisumu are already quite environmentally aware and there is a
group of teachers who run Kisumu Science Teachers Otter Conservation Development
Group (KISTOC).
It is proposed to start this programme here and then hopefully other communities
on Lake Victoria will also be encouraged to follow their example.
