FATE AND EMERGENCE SUCCESS OF HAWKSBILL (ERETMOCHELYS IMBRICATA) NESTS IN THE

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FATE AND EMERGENCE SUCCESS OF HAWKSBILL
(ERETMOCHELYS IMBRICATA) NESTS IN THE COMARCA
NGÖBE-BUGLÉ AND BOCAS DEL TORO PROVINCE, PANAMA
Cristina Ordoñez1, Peter Meylan2, Anne Meylan3,
and Emma Harrison4
1 Sea Turtle Conservancy, Correo General, Bocas
del Toro, Bocas del Toro Province, Republic of
Panama, e-mail cristinao_at_conserveturtles.org 2
Natural Sciences, Eckerd College, 4200 54th Ave.
S., St. Petersburg, Florida 33711, USA 3
Florida Fish and Wildlife Conservation
Commission, Fish and Wildlife Research Institute,
100 8th Ave. SE, St. Petersburg, Florida 33701
USA 4 Sea Turtle Conservancy, Apartado Postal
246-2050, San Pedro, Costa Rica
BACKGROUND Sea turtles are a fundamental
component of marine and coastal environments in
Bocas del Toro Province and the Comarca
Ngöbe-Buglé, Panama, and there is a long history
of both commercial and subsistence use of
hawksbills (Eretmochelys imbricata) and green
turtles (Chelonia mydas) in the region. At the
eastern limit of this region is Playa Chiriquí
(08 56 N, 081 39 W), described by Dr Archie
Carr as one of the most important hawksbill
nesting sites in the Caribbean (Carr, 1956).
Hawksbill turtles were an important part of the
regional economy for at least 200 years. Roberts
(1827) described the commercialization of
tortoise shell in the region in 1815. During the
mid-twentieth century the Panamanian government
leased nesting beaches in the region to
veladores, who paid for the rights to all the
hawksbills that nested in their section of beach.
Interviews with veladores in the 1980s
revealed that as many as 35-50 hawksbills were
killed per night per mile at the start of the
1950s (Meylan Donnelly, 1999). Information
from terrestrial and aerial surveys conducted in
the 1980s and 1990s (Meylan Donnelly, 1999)
suggested a 98 decrease in hawksbill nesting at
Playa Chiriquí, compared to the levels in 1950
these surveys also revealed the continued
presence of a few nesting hawksbills at Playa
Chiriquí (Meylan et al., 1985). The observed
decline was attributed to the extensive harvest
of turtles to meet the demands of the
international trade in hawksbill shell. Figures
1 and 2 show a nesting hawksbill and
hatchling. In 2003, a consortium of interested
individuals and organizations, including the
Wildlife Conservation Society (WCS) and the Sea
Turtle Conservancy (STC), established a
standardized monitoring and protection program at
Playa Chiriquí, Isla Escudo de Veraguas (located
14km off the coast at Playa Chiriquí), and the
two Cayos Zapatillas in Parque Nacional Marino
Isla Bastimentos (PNMIB). Subsequently,
additional beaches were added to the program
Playa Roja, to the west of Playa Chiriquí (2005)
and Playa Larga in PNMIB (2006) (see Table 1 and
Figures 3 and 4). The long-term goal of the
project is to increase the populations of
hawksbill turtles that nest within Bocas del Toro
Province and the Comarca Ngöbe-Buglé. Nesting at
all of these beaches has increased since this
project began and substantial numbers of
hawksbill nests are now being deposited annually
on these beaches (Meylan et al., in press). The
objective of this report is to describe the major
threats to the survival of hawksbill nests at the
beaches listed above, including erosion,
predation and poaching, and to show the variation
in emergence success observed in three nesting
seasons. We highlight the major problem of nest
predation by domestic dogs at Playa Chiriquí,
where as much as 30 of nests were lost to
predation annually. A review of the
effectiveness of techniques that have been
implemented to reduce dog predation are
presented, and recommendations for the future are
discussed.
Figure 1. Nesting female hawksbill, Cayos
Zapatillas, Panama, 2010 (Photo by R.
Fernandez-Francis)
Figure 2. Hatchling hawksbill, Cayos Zapatillas,
Panama, 2010 (Photo by R. Fernandez-Francis)
STUDY SITES
Figure 3. Protected area (A) and major hawksbill
nesting beaches (B) in Bocas del Toro Province
and the Comarca Ngöbe-Buglé, Panama (Redrawn from
Meylan, Meylan and Ordoñez, in press)
Figure 4. Major hawksbill nesting beaches in
Bocas del Toro Province and the Comarca
Ngöbe-Buglé, Panama. From left to right are
Playa Larga, Cayos Zapatillas (A Grande and B
Pequeño), Playa Roja, Isla Escudo de Veraguas and
Playa Chiriquí
LITERATURE CITED Carr, A.F. 1956. The Windward
Road. Alfred Knopf, New York. 258 pp. Meylan,
A.B., Meylan, P., Ruiz A. 1985. Nesting of
Dermochelys coriacea in Caribbean Panama. Journal
of Herpetology. 19 (2) 293-297. Meylan, A.B.,
Meylan, P. Ordoñez Espinosa, M.C. In press. Sea
turtles of Bocas del Toro Province and the
Comarca Ngöbe-Bugle, Republic of Panama.
Chelonian Conservation and Biology. Meylan, A.B.
Donnelly, M.D. 1999. Status justification for
listing the hawksbill turtle (Eretmochelys
imbricata) as critical endangered in the 1996
IUCN Red List of Threatened Animals. Chelonia
Conservation and Biology 3(2)200-224. Roberts,
O.W. 1827. Narrative of voyages and excursions on
the east coast and in the interior of Central
America. Univ. of Florida Press, Gainesville. 302
pp. Reprint 1965.
Table 1. Description of study sites
Study sites Length (km) Protected Area? Poaching Eggs/Females? Human Use Access by communities Predators (decreasing order)
1 - Playa Larga 4.3 National Marine Park Y/Y Tourism, travel route, fishing, hunting Limited by distance, geography Raccoons, crabs,
2 - Cayos Zapatillas 4.2 National Marine Park Y/N Tourism, coconut plantations Limited by geography Crabs, birds, insects
3 - Playa Roja 2.5 No protection Y/Y Travel route, fishing, farms Community at one end Dogs, crabs, raccoons
4 - Escudo de Veraguas 5.6 Protected Landscape Y/Y Fishing, coconut plantations, tourism Limited by geography Crabs, insects
5 - Playa Chiriquí 24 RAMSAR Protected Wetland Y/Y Travel route, fishing, farms Communities at both ends Dogs, crabs, insects
ACKNOWLEDGEMENTS National Environmental Authority
of Panama (ANAM), General and Ño Kribo Regional
Congress of the Comarca Ngöbe-Buglé, Association
for the Protection of the Ngöbe-Buglé Natural
Resources (APRORENANB), Association for the
Conservation of the Ngöbe-Buglé Natural Resources
(ACORENANB), Smithsonian Tropical Research
Institute (STRI), Florida Fish Wildlife
Conservation Commission (FWC), Sea Turtle
Conservancy (STC), Eckerd College (EC), National
Fish and Wildlife Foundation (NFWF), the Wildlife
Conservation Society (WCS), monitors and
volunteers from Río Caña, Río Chiriquí, Salt
Creek, Isla Popa, Carenero, Playa Colorada and
Cayo Paloma communities, and field coordinators.
Cristina Ordoñez would like to thank the
International Sea Turtle Society, Western Pacific
Regional Fishery Management Council, U.S. Fish
and Wildlife Service, and U.S. National Marine
Fisheries Service for the Travel Grant that
allowed her to attend the symposium.