Social and Economic Aspects of Sea Turtle Conservation
377
sea turtles necessary to support an economically sustainable egg harvest. To our
knowledge, no economist has provided an estimate of the minimum number of eggs
necessary to support a sustainable market. Even if such an estimate were available,
it is clear that harvesting sea turtle eggs is probably not sustainable if the population
is also being subjected to human-induced mortality at other life stages (Hope, 2000).
For example, it is highly unlikely that a sea turtle population could support both
harvesting of its eggs and incidental mortality in trawl fisheries or directed take of
adults and juveniles in a turtle fishery. As indicated above, although it may be
desirable in a strictly economic sense to exploit a biological resource to extinction
in order to maximize a profit that would then be invested in other commodities (Clark,
1973), this is not acceptable if the goal is sustainability of the resource.
Similarly, to our knowledge no one has provided estimates of the minimum
number of turtles (or kilograms of meat or tortoiseshell) that would be necessary
for economic sustainability of a turtle fishery. Therefore, it is not possible to calculate
the population size necessary to sustain such a fishery biologically. Most models of
turtle population dynamics lead us to the conclusion that harvesting such long-lived,
late-maturing species is not sustainable (Congdon et al., 1993; 1994; Crouse et al.,
1987; Crowder et al., 1994; Heppell et al., in press). If that is the case, then there
is no finite population size, however large, that would allow a sustainable take of
adults or larger juveniles. However, from a purely monetary standpoint, we reiterate
that it might be deemed desirable to exploit a species to extinction in order to
maximize profits to reinvest in other markets (Clark, 1973). This option is likely to
be unacceptable to anyone interested in the conservation of sea turtles or of biodiversity in general.
14.10 CONCLUSIONS AND RECOMMENDATIONS
Sea turtles have worth that is widely experienced yet seldom measured. Sea turtle
value should guide our conservation efforts, and a comprehensive understanding of
their total value should accompany any proposal for their use. Some sea turtle
harvests may have important cultural roles and some incidental take may occur
despite our most diligent application of mortality-reducing methods. However, even
if this sea turtle consumption were sustainable, it could still diminish the value of
competing enterprises such as ecotourism or reduce the ecological function of sea
turtles and sea turtle phenomena. The effects of direct and indirect take on nonconsumption and nonuse values, coupled with the temptation for optimal extinction of
sea turtle resources, mandate careful scrutiny of any proposal involving consumption
of sea turtles.
Contingent valuation studies are needed to measure the total value of sea turtle
resources so that all parties that value them can be represented in equitable resourceuse decisions. Conserving sea turtles will always involve costs, which might be
justifiable by measuring a willingness to pay among stakeholders. Many conservationists have realized the potential for generating willingness to pay by the media
showcasing of sea turtle charisma. It remains a challenge for conservationists to
gently focus the ensuing financial attention in biologically appropriate directions
without ignoring the empathy of the public for individual turtles.
1123 book.book Page 377 Monday, November 11, 2002 11:11 AM
377
sea turtles necessary to support an economically sustainable egg harvest. To our
knowledge, no economist has provided an estimate of the minimum number of eggs
necessary to support a sustainable market. Even if such an estimate were available,
it is clear that harvesting sea turtle eggs is probably not sustainable if the population
is also being subjected to human-induced mortality at other life stages (Hope, 2000).
For example, it is highly unlikely that a sea turtle population could support both
harvesting of its eggs and incidental mortality in trawl fisheries or directed take of
adults and juveniles in a turtle fishery. As indicated above, although it may be
desirable in a strictly economic sense to exploit a biological resource to extinction
in order to maximize a profit that would then be invested in other commodities (Clark,
1973), this is not acceptable if the goal is sustainability of the resource.
Similarly, to our knowledge no one has provided estimates of the minimum
number of turtles (or kilograms of meat or tortoiseshell) that would be necessary
for economic sustainability of a turtle fishery. Therefore, it is not possible to calculate
the population size necessary to sustain such a fishery biologically. Most models of
turtle population dynamics lead us to the conclusion that harvesting such long-lived,
late-maturing species is not sustainable (Congdon et al., 1993; 1994; Crouse et al.,
1987; Crowder et al., 1994; Heppell et al., in press). If that is the case, then there
is no finite population size, however large, that would allow a sustainable take of
adults or larger juveniles. However, from a purely monetary standpoint, we reiterate
that it might be deemed desirable to exploit a species to extinction in order to
maximize profits to reinvest in other markets (Clark, 1973). This option is likely to
be unacceptable to anyone interested in the conservation of sea turtles or of biodiversity in general.
14.10 CONCLUSIONS AND RECOMMENDATIONS
Sea turtles have worth that is widely experienced yet seldom measured. Sea turtle
value should guide our conservation efforts, and a comprehensive understanding of
their total value should accompany any proposal for their use. Some sea turtle
harvests may have important cultural roles and some incidental take may occur
despite our most diligent application of mortality-reducing methods. However, even
if this sea turtle consumption were sustainable, it could still diminish the value of
competing enterprises such as ecotourism or reduce the ecological function of sea
turtles and sea turtle phenomena. The effects of direct and indirect take on nonconsumption and nonuse values, coupled with the temptation for optimal extinction of
sea turtle resources, mandate careful scrutiny of any proposal involving consumption
of sea turtles.
Contingent valuation studies are needed to measure the total value of sea turtle
resources so that all parties that value them can be represented in equitable resourceuse decisions. Conserving sea turtles will always involve costs, which might be
justifiable by measuring a willingness to pay among stakeholders. Many conservationists have realized the potential for generating willingness to pay by the media
showcasing of sea turtle charisma. It remains a challenge for conservationists to
gently focus the ensuing financial attention in biologically appropriate directions
without ignoring the empathy of the public for individual turtles.
1123 book.book Page 377 Monday, November 11, 2002 11:11 AM