| Satellite tracking studies
have revealed the direct route that individuals take back to Brazil,
a trip that takes some six weeks. Here algae are plentiful and the
turtles feed until they have enough fat reserves to sustain the
migration to and from Ascension Island and to produce their clutches
of eggs. We do not know how the turtles find Ascension Island, but
theories range from olfactory (smell), visual and auditory (sound)
cues, to innate maps and magnetic fields. Recent work on Ascension,
with females being displace offshore with satellite transmitters
attached have suggested that, at least a few hundred kilometres
away, the turtles may be able to smell the island downwind. Until
recently, it was assumed that the males, which are smaller than
the females with a long tail) also live in Brazil. In 2000 this
was confirmed when 2 male turtles were tracked using satellite transmitters.
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