HURL submersibles have not just one but two encounters
with Great White sharks!
By Terry Kerby
October 28, 2002, the Pisces IV submersible was conducting a dive
on Penguin Bank, a well known Hawaiian bottomfishing site near the
island of Moloka'i, when it had a chance encounter with a Great
White Shark, Carcharodon carcharias. Robert Moffitt of NOAA Fisheries
was the Principal Investigator and the dive was one of 12 he was
awarded to examine the recovery rates of areas closed to bottomfishing.
Pilot Chuck Holloway was maneuvering the Pisces IV along the 350
m (i.e., 1150 ft) contour while observers Walter Ikehara and Jane
Culp were looking through the ports identifying and counting all
fish and invertebrates they could see. Suddenly a large shark moved
quickly at the sub and bumped into the upper video camera knocking
the laser ring loose. The camera recorded a quick glimpse of a nose
and eye as it flashed by. This video image was distributed to a
number of shark experts who verified that it was most likely a Great
White. Fortunately for the many tourists who come to the islands
to swim and dive, this species is rarely seen in this part of the
Pacific. It's also rare to record a Great White from a submersible
so the encounter wound up being shown in a Discovery Channel documentary
called "Jaws of the Pacific".
Well, sometimes lightning really does strike twice.
On October 4, earlier this year, the Pisces V was conducting precious
coral research dives off of Oahu when there was another encounter!
This time, I was piloting and had just landed on the bottom at 446m
(i.e., 1,463 ft). Principal
investigator Amy Baco-Taylor and BBC cameraman Tom Fitz were on
board and were just settling into position to start observations
while I was adjusting the trim. Just prior to lifting off, I caught
a glimpse of something large approaching the sub, which then turned
sideways presenting the unmistakable profile of a Great White. This
encounter was not a quick hit and run; the animal swam up to the
Pisces V, turned, and passed right in front of the sub before swimming
slowly away. I was able to estimate its length at 13 ft and clearly
determine it was a female. This one had a huge girth which Great
Whites are known for but also she may have been pregnant.
These encounters raise some interesting questions according
to HURL biologist, Chris Kelley. Was it just extraordinary luck
to have this happen twice or are there more of these sharks in Hawaiian
waters than we realize? What are they feeding on below 1,000 ft?
Hawai'i has no sea lions and while there are a number of monk seal
colonies in the Northwestern Hawaiian Islands, there are none in
the main Hawaiian Islands. What are they doing down there? Was the
female really pregnant and if so, could Great Whites be breeding
or at least giving birth to their pups in deep water? Could Hawai'i
be a breeding ground for this species and could that be why tracking
data has shown these sharks to be migrating between the West Coast
and the islands?
We don't yet have answers to these questions but
you can bet we'll be keeping our eyes open on future dives, just
in case lightning strikes for a third time.