Although it was eight years ago, I still remember my first encounter
with a sawfish as one of the most extraordinary experiences of my life.
And, in light of our recent paper ‘
Occurrence and habitat use of the Critically Endangered small tooth sawfish, Pristis pectinata in the Bahamas’ being accepted by the
Journal of Fish Biology, I feel it’s appropriate to recollect that moment now.
Grant Johnson (former sharklab manager) releasing the sawfish after capture. Photo by © Matthew Potenski.
Every summer in the months of May and June researchers at the
Bimini Shark Lab
set gill nets in North Bimini’s mangrove-fringed nursery areas to
capture newborn and juvenile lemon sharks. The nets are anchored at the
edge of the mangroves and pulled offshore, then set for 12 hours
overnight and for six consecutive nights. The target species is the
lemon shark, but every now and again something special makes an
appearance.
Removing a lemon shark from a gillnet. Photo by © Charlotte Sams.
It was the first night of the North Bimini juvenile lemon shark
tagging programme, 2007. I was leading a gill-net set on the western
edge of the North Lagoon. The water was about one metre deep and the
substrate was rocky with patches of sand. At about 11 pm, an hour or so
past high tide, our team was on its usual 15-minute check, flashing the
torch down the net as we putted alongside in our boat and viewed the
water from the surface. Suddenly splash, struggle – a shark was tangled
in the net, then another and a few metres later there was a bigger
splash. Excitedly, within the space of 60 seconds all my team had
launched themselves into the water to rescue our catch: two juvenile
lemon sharks and a bonefish.
Shark tagging during annual tagging program. Photo by © Charlotte Sams.
Knowing that other sharks might be caught in the last two sections of
the net, I reassured my team that I would collect them and the sharks
on the way back and continued the check. I motored slowly along the
length of the net, inspecting it carefully and methodically. As I got
closer to the mangrove edge, I noticed that a large section – about 15
metres – of the net had turned into a huge cloud of silt. I couldn’t see
a thing. My first thought was adult lemon shark (yippee) and then I
considered big nurse shark (oh no – the net would be destroyed). The
Shark Lab frequently documents both species in shallow water during
summer, either pupping or seeking mates, so it was possible that one had
got tangled up.
Smalltooth sawfish with tracking device. Photo by © Matthew Potenski.
The current gradually cleared the silt away and, to my absolute
amazement, surprise and excitement, out of the murk appeared the
instantly recognisable rostrum of a sawfish, with its evenly spaced
teeth like a prehistoric caveman’s weapon. Ecstatic, I roared at the top
of my voice, ‘Oh my god, it’s a sawfish, we’ve caught a sawfish.’ Then I
shouted down the radio, ‘We’ve caught a sawfish, a sawfish, woohoo.’
Wilson, one of the volunteers, answered, ‘You’re joking!’ ‘Do I sound
like I am joking?’ I gasped.
Smalltooth sawfish reflection. Photo by © Matthew Potenski.
Within quick succession, there were yelps of joy and cheers down the
radio and across the sound! Any normal person would have thought we had
won the lottery or that a boat full of pirates’ treasure had got caught
in our net. To us, this
was the lottery – one of the rarest, most imperilled creatures in the ocean and we had the privilege of seeing it up close!
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