Publication Date:
2021-05-19
Description:
Analysis of long-term (1978–2001) marine fisheries data showed that Kenyan coralreefs
produced an estimated 2–4 metric t/km2/year of demersal fish. A rapid overall decline in
landings occurred during the 1990s. Yields (t/km2/year) showed bimodal peaks in 1982 (2.98)
and 1991 (2.90). The average total landings dropped by 55% during the last decade following
peak landings in 1982. Landings of the commercially important families (e.g., Siganidae,
Lethrinidae, Lutjanidae and Serranidae) declined by about 40% during the last decade, with the
groupers (Serranidae) showing the steepest (72%) decline. Analysis of landings per
administrative district showed a 78% decline in the densely populated Mombasa district between
the periods 1983–1991 and 1992–2001. The less populated districts have registered stable (e.g.,
Kilifi) to increasing (e.g., Kwale) catches over time. An autoregressive moving average (ARIMA)
model forecast of landings predicted a gradual decline in catches during the next decade (2002–
2011) with a trend slope of -0.01 t/km2. Length-frequency analysis for the commercially
important species indicated above optimum exploitation (E) and fishing mortality (per year)
rates for the sky emperor, Lethrinus mahsena (E = 0.64; F = 2.48) and lower but strong rates for
the emperor, L. sangueinus (E=0.51; F=0.93). The more abundant and commercially important
whitespotted rabbitfish, Siganus sutor, showed equally strong rates (E= 0.56; F = 1.44/year). A
precautionary approach in the management of Kenya’s coral-reef fisheries is recommended.
INTRODUCTION
Fishing is the dominant extractive activity in
Oceania and an important source of income and
sustenance in coastal communities worldwide.
However, in the past decade many marine fisheries
resources have declined (FAO, 1995). Although
ocean climate variation has likely played an
important role in many regional declines (Lauck
et al., 1998; Drinkwater & Mountain, 2002), the
most important factor has been overfishing (Pauly
& Christensen, 1995; Hutchings, 2000; Rose et al.,
2000). The effects of fishing have been the subject
of recent reviews (Jennings & Polunin, 1996;
Jennings & Kaiser, 1998). Growth overfishing
reduces the size and yield of target species
Description:
Published
Keywords:
Coral reefs
;
Reef fish
Repository Name:
AquaDocs
Type:
Journal Contribution
,
Refereed
,
Article
Format:
602417 bytes
Format:
application/pdf
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