Page 605 - The British Big Four

Post-Hatchling Stage/Juveniles

First, here is lesser exposure to the intense second, the long interval between breeding sea- fishes, crustaceans, worms, molluscs, tunicates
heat of day which can easily be fatal to them. sons. The effective fecundity is measured by the and coelenterates that seemed suitable forage
There exists a direct pressure for the develop- average annual production of hatchlings in the for little turtles. Besides that advantage and the

ment of a thermal inhibition of activity. Second, open water dispersal phase per adult female in concealment the rafts offered, there was the fun-

this provides better protection from terrestrial the total population. For a species to survive, a damentally important tendency of the mats to be

and airborne predators. Furthermore, even when consequence of such low fecundity and such high aligned off high-energy beaches and thus to en-

daytime temperatures are not high enough to kill longevity to sexual maturity would have to be a hance the probability that the seaward course of

the hatchlings, but only to slow them down, the very high annual survivorship of the turtles in all little turtles leaving a nesting shore would inter-

longer time in reaching the sea gives predators posthatchling life history phases and/or a very cept them (Carr, 1986). Seaweed drifts may act as

a better chance of making a catch. Upon enter- long reproductive life (Limpus, 1994). fish nurseries providing food and shelter. Floating

ing the sea, hatchlings swim below the surface, logs, coconuts, and other jetsam may attract small
Ocalled swimming frenzy, making little attempt to
nce they have passed through the surf, they turtles where floating weed is absent (Carr, 1987).
dive deeply. Green and loggerhead hatchlings are would not be seen again in the waters of the
capable of swimming 20-70 km in two days unas- continental shelf until they reached sizes between
ost-hatchling turtles are rarely observed in
Psisted by currents. Such distances are greater than those of a saucer and a dinner plate. This is called coastal habitats and in most cases are as-

would be necessary to escape immediate littoral the “lost years” of the turtle’s life. The smallest tur- sumed to disperse to the open sea. Encounters

and sub-littoral predators and may in some places tles normally encountered in coastal habitats are are too infrequent. Walker (1994) stated that small

be sufficient to reach offshore current systems now thought to be considerably older than one chelonids have the ability and desire to move

(Hughes, 1974 in Walker, 1994). year ( Walker , 1994). from a pelagic to a benthic habit but until then,

The large number of eggs laid in a single sea- Sargassum rafts have been observed to be the their location at sea will be at least partially de-
son is offset by two factors: first, the high egg lost year refuge for green turtles and logger- pendent on currents and ocean drift. Departure
from a pelagic habitat is probably opportunistic

and hatchling mortality on the beach and in the heads. These brown algal mats harbor a diverse, and not necessarily linked to turtle size.

waters immediately adjacent to the rookery and specialized fauna, including many kinds of little