Sea Turtle Recovery Action Plan for St. Kitts and Nevis - WIDECAST

St. Kitts and Nevis Sea Turtles…
glass, water; the sand may be too dry to hold a nest cavity), and injuries such as a missing
flipper. If funds become available, personnel should be hired to conduct nocturnal censuses of
important nesting beaches in order to document the actual deposition of eggs. A nest:false crawl
ratio determined from the night patrols will permit an estimate of nest density from crawl tallies
obtained during day census efforts. In the interim, pending financial support for comprehensive
surveying, full advantage should be taken of the willingness of volunteers to walk beaches and
collect data on nest distribution and abundance.
It is usually difficult to confirm eggs during day surveys, but sometimes the outcome is
obvious. For example, sometimes it is clear that a turtle returned to the sea without attempting to
dig. This is a "false crawl" and should be reported as such. Alternatively, when a poacher or
predator has exposed eggs, or hatchlings are observed, nesting can be confirmed. When the
activity site includes both a crawl and an associated disturbance which may or may not contain
eggs, distinguishing a true nest from an unsuccessful attempt is challenging even for an
experienced worker. Probing for the eggs with a sharp stick will sometimes confirm the
presence of a nest, but this is strongly discouraged because subsequent bacterial invasion of the
broken eggs may destroy the entire nest. In the case of hawksbill nests in dense vegetation, even
finding a site suitable for probing can be difficult. Hence the logic that crawls, rather than nests,
be the basis of reporting. When a crawl has been counted, it should be disguised with a palm
frond or a gentle sweeping motion of hands or feet in order to dissuade possible poachers from
finding the site and also to prevent the crawl from being counted twice.
Identifying the crawl to species is easy in many cases, since sea turtles leave either a
symmetrical or an asymmetrical track in the sand. In the first case, the pattern is made by the
simultaneous movement of her flippers. In the second case, the pattern alternates like a zipper, a
result of the turtle moving her front flippers in an alternating rhythm. Leatherbacks leave a deep,
symmetrical crawl about two meters in width. Green turtles also leave a symmetrical crawl, but
it is only about one meter in width and the nest site is often characterised by a deep, solitary pit a
meter or more in depth and breadth. Hawksbills and loggerheads leave an asymmetrical crawl,
the hawksbill about 0.7 m in width and the loggerhead about 1.2 meter in width. The hawksbill
crawl is often very faint, however, since the animal averages a mere 54 kg (Caribbean
Nicaragua: Nietschmann, 1972 in Witzell, 1983). Loggerheads are typically twice as massive,
averaging about 116 kg in Florida (Ehrhart and Yoder, 1978 in Dodd, 1988). In addition,
hawksbills will often make their nests deep within the shelter of Coccoloba or other beach
vegetation.
Once the nest:false crawl ratio has been determined for a beach and the number of nests
laid (per species) is known, a knowledge of the average number of clutches laid per female
(which varies slightly amongst species and can be gleaned from well-studied populations
elsewhere in the region) can be used to estimate the number of breeding females at that site. As
a general rule, leatherbacks average 6-7 nests per summer, hawksbills 5 nests, and green turtles
4-5 nests. Thirty hawksbill tracks on a beach may represent only 20 actual nests, which in turn
represent only four adult females. To obtain a more accurate assessment of the number of
females nesting per year on a particular beach, as well as the return intervals both within and
between seasons by individuals, all-night patrol must be undertaken by trained personnel and the
tagging of nesting females initiated. Tagging is not something to be undertaken lightly. It is time-
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