since you have like 15 of them?

That's pretty hard.

(Jill) It is hard at first.

We actually have this really great photo album that I would love to show you guys, and this would be our first step in helping you learn how to identify them.

Let's go check that out.

♪ ♪ This is our family album, and we have a ton of pictures in here of each one of our dolphins and some of the identifying features we use.

The dorsal fin is like a fingerprint.

There are no 2 that are exactly identical.

So this is Ding's, very triangular and short.

That's L.B.

Huge difference.

This is Mr. Elvis.

He has a very short rostrum.

The rostrum is their snout.

(Izzie) Hm, dorsal fin, rostrum--lots to learn!

He's one of the darker dolphins that we have.

Now, Miss Nica who looks very different from Elvis.

She's extremely slender, she has a very long, thin rostrum.

Overall, she's very petite.

Her dorsal fin is more triangular.

How old is Nica?

Nica just turned 5, and Elvis will be 5 shortly, in a couple of weeks.

When did you first know that you wanted to work with dolphins?

(Jill) Well, my passion for the ocean started really young.

I was born in Miami, but I actually lived on a boat with my whole family for about 2 years in the Caribbean.

So I spent hours and hours every day snorkeling some of the most pristine marine environments in the Caribbean, and it really motivated me to pursue my studies to hopefully one day make a difference.

I work at the University of Miami, so I teach undergrads, I also run a nonprofit organization where I try to bring marine science experiences to underpriviledged kids.

I have a 3-year-old who thinks that it's normal to spend your life with dolphins.

[SciGirls laugh] (Jill) He is the light of my life, he is amazing.

(Serena) After Jill gave us that ID book.

That gave us a really good idea of who's who.

I would like to show you this DVD that we have.