NARRATOR: Next day back in the Polynesian town of Papetoai,
they visit an expert who ID sharks by their fins.
So we were hoping to see if you could look
through some of your databases.
NARRATOR: Shark scientist Nicolas
Buray keeps a photo archive of Tahitian tiger sharks.
That's cool.
NARRATOR: And it's been growing.
MAN: How many sharks do you have in your database?
So in our database, we have around 55
different tiger sharks.
This is new.
For 10 years, I saw maybe two only.
Right now, since three, four, five years,
we are more and more tiger sharks.
NARRATOR: Local divers send Nicolas dorsal fin shots.
He enters them into the archive and identifies the individuals.
So you're looking at the stripe patterns?
Yeah, the stripe.
When a shark's growing, they keep the same stripe.
NARRATOR: All of the newcomers are females.
Time to find out if they have a match.
This one here is Kamakai.
And the dorsal is pretty distinct.
She is mature, so there's some scarring.
NARRATOR: During mating, male sharks
bite the females, which is why female shark skin
has evolved to be super thick.
Female tigers reach sexual maturity at about 9 years.
There's no doubt Kamakai has mated.
Clearly a big female tiger shark.
But do you recognize her?
Or is she in your database?
I mean, no. No.
Not in my database.
ANDY: OK.
No.
This one is, I'm sure I don't know it.
NARRATOR: Now they compare pictures
from the database with the big females from the night dive.
This is the biggest one that we've seen there.
We were thinking possibly the same shark.
No.
For me, it's not the same.
So this one I think is not the same.
NARRATOR: Andy and Kori have just
added three new large females to Nico's growing database.
Do have the other side?
No.
NARRATOR: That makes more than 40 large sexually mature
female tiger sharks, most with dorsal fins
chewed up and scarred for mating.
Looks like just a shredded fin.
NARRATOR: Everything points to a tiger shark mating ground.
An area with males must be nearby.
So that means those other hot spots out there, other places
where these large tiger sharks are hanging out
that haven't been studied yet.
NARRATOR: If they can find it, perhaps Kamakai will
be there looking for a mate.