Sticking up out of the sea, a short flight from Sydney, is
one of Australia’s best kept secrets, Lord Howe Island. Emerald green forests
drape rocky mountains overshadowing turquoise lagoons and bays of Earth’s
southernmost coral reef. Providence Petrels, all 40,000 breeding pairs, can be
heard calling and seen in courting displays of aerial acrobatics, buzzing
around the mountain tops like flies. This truly is a paradise of unimaginable beauty.
As part of my Masters degree research, I’ve come to check
out the sea turtles, if there are any. I had heard some reports of sightings at
Lord Howe Island and read some pretty interesting reports about satellite tracking
loggerhead turtles that were released here, but there doesn’t seem to be much
by way of modern research.
Steeped in history dating back to the island’s discovery in
1788, many of the ships captains recorded details about sea turtles in the
lagoon of Lord Howe Island. Although sea turtle never made the menu for Lord
Howe Island locals, it seemed commonplace for whaling and trade ships to
collect turtle from the lagoon, 20 – 30 at any one time. The turtles would be
kept live on deck and transported to the first settlement in Port Jackson and
also to Norfolk Island. The whaling trade came to an end and the
increasing local settlement became skilled at farming pig and goat, the taking
of turtles from the island appears to have ceased in the early 1900’s.
Joyce Petherick, born 1921, recalls swimming across the
lagoon as a young girl and her observations were echoed through the older
community, seeing a sea turtle was an exciting surprise, not a daily
occurrence. Fast-forward to 2014 and now there are multiple daily glass-bottom boat
turtle tours operated throughout the lagoon. I jumped onboard and let the
locals show me where the turtles are. Within minutes I was hovering over greens
and hawksbills comfortably going about their business. Another scuba-diving local
pointed out that he had never seen a loggerhead turtle there before, until just
a few months ago he sighted an adult at Yellow Rock at a depth of around 16m.
As word got around the island about who I am and why I was
there, I came into possession of two hawksbill turtle carcasses that had
beach-cast dead. For the purposes of determining the cause of death I conducted
necropsies of both individuals. This was not pretty. They both presented almost
identically in size and condition (and odour) and appeared to have starved to
death. They were quite young and not unlike the 70 odd individuals beach-cast
dead in northern NSW only a couple of years ago, interesting. Victims of
ontogenetic shift mortality? I collected DNA and it may be possible to
correlate these with natal grounds known in the South Pacific, if I can find
funding.
