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Three species received an Overall Sustainability
Recommendation of Avoid: Queen Conch, Grouper and Snappers.
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Studies indicate that nearly one third of global sea fisheries
have already collapsed and that the rate of decline is accelerating.
One billion people, the world over, rely on seafood (fish and shellfish)
as either their main or sole source of protein, thus the current
state of the world's fisheries is a matter of great concern.
Amidst this background of declining fisheries, the Buccoo Reef
Trust has embarked on a Campaign to raise awareness of important
ocean conservation issues and to shift the purchasing habits of
consumers, restaurateurs and other seafood purveyors to sustainable
sources of seafood. Sustainable sources of seafood are defined as
seafood originating from species, wild-caught or farmed, that can
exist in the long-term through maintained or increased stock abundance
and conservation of the structure, function, biodiversity and productivity
of the surrounding ecosystem. If consumers are provided with recommendations
and background information regarding the fish products they buy,
they will be better equipped to make more environmentally sound
choices.
Phase I of this project involved the production of this Species
Evaluation Report. In this report the ten most popular seafood species
in Tobago (kingfish, wahoo, flyingfish, dolphinfish, tuna, snapper,
grouper, conch, lobster and shrimp), as determined from a survey
of local restaurants, were evaluated based on 5 criteria (adopted
from prominent seafood evaluation guidelines) and then assigned
an overall sustainability recommendation of: Best Choice, Good Alternative
or Avoid.
Recommendations
Three species received an Overall Sustainability Recommendation
of Avoid: Queen Conch, Grouper and Snappers.
The
evaluation report for this species reveals that Queen conch, (Strombus
gigas), is inherently vulnerable to fishing pressure. They
mature at a late age compared to other conch species, are highly
vulnerable to predation as juveniles, and inhabit nearshore shallow
waters making them easy targets for fishers. Furthermore, they form
huge spawning aggregations, which makes it easier for them to be
exploited in large numbers during the breeding cycle and when populations
are too sparse, the adults no longer breed. With respect to stock
status, throughout much of its range, the queen conch is overfished,
and many fisheries have been closed because of overfishing. Because
of international concerns about the continuing decline in stocks,
queen conch was placed on CITES Appendix II (species that are not
necessarily now threatened with extinction but that may become so
unless trade is closely controlled) in 1992. A 2003 review by CITES
found that just two conch-exporting nations (Jamaica and Turks/Caicos)
had adequate management and stocks that were “probably not
overfished” while most other nations needed to conduct stock
assessments and take basic steps to curb rampant illegal fishing.
In Trinidad and Tobago there are signs that stocks are near collapse
and there is no management plan for conch at present.

Groupers, like conch, possess a suite of life history characteristics
which make them highly susceptible to overfishing. Apart from being
long-lived (12-41 years), with slow growth rates and a long population
doubling time, groupers exhibit a phenomenon know as “protogyny”.
This means that they begin their lives as females and then some
portion of the population transforms into males as they become larger.
The consequence of this is that, since the largest members of grouper
populations are likely be male and fishing pressure is often focused
on the largest individuals; sex ratios can be rapidly altered with
the removal of the larger males. To compound the overfishing scenario
even further, groupers form dense spawning aggregations at the same
sites (site fidelity) year after year. This predictability allows
fishermen to catch a large number of fish in a short space of time.
The decline in spawning aggregations ultimately results in the reduction
of the population because fewer and fewer fish are reproducing each
year. In some cases intense fishing on these aggregations can result
in the extinction of an aggregation.
Two of the most popular grouper species locally are the yellowmouth,
(Epinephelus flavolimbatus), and yellowedge, (Mycteroperca
interstitialis), grouper. In recent times a decrease in the
catch rates at traditional fishing grounds has lead to an expansion
of the fishery into new areas. This suggests that stocks are fished
beyond yields that the population can sustain. Long-term and short-term
trends in biomass for most of these stocks are unknown. There is
no management plan for the fishing of grouper stocks in Trinidad
and Tobago. Anecdotal information suggests that stocks have declined
and there is urgent need to put management measures in place immediately.
The
two main snappers landed in Tobago are the plumhead/vermilion snapper
(Rhomboplites aurorubens) and the Caribbean red snapper
(Lutjanus purpureus). Preliminary stock assessments conducted
on these snappers landed by the Fishpot fishery of Tobago in 1993
indicated that, at that time, these stocks were over-exploited and
fully exploited respectively. Recommendations arising from this
study were never implemented. No recent assessment has been conducted
on snappers in local waters hence there are no estimates of biomass,
optimum yield or maximum sustainable yield (MSY). There is no management
plan for snappers at the sub-regional or national level. In the
absence of a biological data collection programme for snappers it
is highly unlikely that a stock assessment could be performed or
that a management plan could be formulated in the near future.
