**Pepperdine University Associate Professor of Biology Karen Martin specializes in the study of Leuresthes tenuis — grunion.
Q: How does one become a grunion professor?
A: It just happens, it’s not something you plan. I like to work on animals I can find easily, and these are the easiest.
The field biologists at Pepperdine like to work on local species. We like to take our students out in the field.
Q: Let’s start with the basics. What are grunion?
A: Grunion are a species of silver-sides fish, found only in Southern California. They love to surf, and they come in on sandy beaches following high tides after a new or full moon. They come in for spawning. That’s called a grunion run. They’re the only fish I know that spawn out of water.
Q: “Spawn.” That’s a polite word for . . . ?
A: When fish want to be together in a special way.
It’s hard not to enjoy working with grunion. They’re a great fish.
I tried to start working with them 10 years ago. I didn’t have the timing down. I started again four years ago. Now we have the timing down.
Q: What does it mean to “study” them?
A: I don’t like to get wet, so the fish come to me. We either collect the fish or we collect the eggs, and we study them.
They lay their eggs where the eggs won’t get wet until they’re ready to hatch. From a biologist’s standpoint, that’s really interesting.
One of the things we study is the way the metabolism of the eggs develops out of water. They don’t have a specific set time, the way most eggs do. They wait for the surf to come back up and wash them out to sea.
It’s like a space capsule. It’s enclosed. There’s no way to get in more food or for the animal to move around. Yet they have to keep metabolizing.
You find it increases until the 10th day, when it is ready to hatch. It keeps that relatively high metabolism for up to an additional four to five weeks, waiting for that trigger.
Q: When can we see them run?
A: For example, they ran on March 20. High tide was 5-1/2 feet above. Then it falls off until after the next new moon. The grunion are waiting for the highest highs and lowest lows.
If you want a fancy, new word: syzygy. It’s when the sun and moon are aligned — the highest high tides and the lowest low tides.
Q: If I’m having difficulty conceptualizing this, how do the grunion figure it out?
A: Fish are really smart. I don’t know how. I don’t think anybody really does.
A lot of animals are on cycles. There is a big movement of the ocean, so it’s easy to understand. But they respond in a pretty precise way. It’s about an hour to an hour-and-a-half window.
Q: Do they talk to each other?
A: They are schooling fish, so they are able to communicate in the sense that they school together.
Q: When is the next run?
A: The night of May 3 at 11:10 or the night of May 4 at 11:45.
I think this is the reason grunion are not studied much. It’s pretty labor intensive. You don’t know that they’re going to be there.
They do this only in the spring, from late March to mid-July, two or three nights after every new and full moon. But some runs are better than others.
Q: Where in Malibu can we see them run?
A: They find a sandy beach with a nice, long, slow wave approach, not necessarily a good surfing beach. The fish actually ride in on the waves.
Q: Why isn’t this a more exact science?
A: They’re like any animal. You think you understand the animal, but . . . .
Rain or storms change the pattern of waves. Sometimes it’s a lovely night, and they don’t show up.
The problem is that there’s a large population of fish, and not all are spawning.
Q: Are these questions you pursue?
A: No, they’re too hard for me. I pursue questions I can answer.
I’m actually a physiologist. So I study their metabolism — the eggs out of water and how adults can be active out of water, yet they’re fish.
Q: Do you recommend the life of a scientist?
A: It’s a different kind of creativity, but scientists must be creative, and they must be original, and they must produce interesting material constantly in such a way that their colleagues accept it.
In some ways it’s like being a poet. If you’re driven, do it. If you have a burning curiosity about the subject, study it. But it’s not easy, and you’re not going to get rich.
Q: But you can stay up late and watch fish.
A: I also study intertidal fish. Part of the reason I got involved in grunion is that low tides are at 5 or 6 in the morning. If you ask a college student if they’d rather stay up ’til 11 or 12 or get up at 5 or 6, a lot will say they’d rather stay up late.
Q: Have you produced that interesting material?
A: [She fishes for a copy of her new book, “Intertidal Fishes — Life in Two Worlds,” Academic Press, 1999, which she co-edited.]
Everything you would want to know about fish is in this book.
Q: Grilled or sauted?
A: People ask me if you can eat a grunion. I say, ‘Yes, but don’t bother.’
Q: Where did you do your studies?
A: University of Oklahoma for undergraduate. It’s pretty far from the ocean. It was covered by an ocean during the Cretaceous period.
I came out here to UCLA to do my graduate work. That’s where I started working on fish.
Then I went to University of Washington at Friday Harbor Labs in the San Juan Islands in Puget Sound for a one-year, post-doctoral fellowship.
My main focus has been fish out of water, which is a metaphor.
Q: For?
A: I suppose for someone like me doing something like this.
Q: Do you catch the grunion?
A: We can only catch the fish with our hands. You have to give the fish a fighting chance, or else it is illegal. Also, it is illegal to catch them in April or May. After May, adults 16 and older can catch them only if they have a fishing license.
My recommendation is: Catch them, look at them and throw them back. You can’t eat them and they don’t live in captivity.
Q: May we discuss delicate matters? What does spawning look like?
A: The female digs tail-first into the sand. The males seem to cue on her movement, so they’ll find her. One or more males may surround a female. They just release their milt.
Q: Pardon?
A: Milt. The sperm.
The eggs are bright orange and full of yolk.
Q: So you can bring the kids?
A: Kids love these things.
Dress warmly and wait. If you go out about the time of the high tide, you see a few fish coming up at first. They might come out for one wave and then be washed back.
If you’re lucky, the numbers might increase.
They’ll be in a narrow band, so you have to get right down to the waterline. They will come in on one of the larger waves, and the fish will remain on the sand to spawn.
The next big wave, the fish will wash right out.
That’s why you have to stay there and be patient. Another wave, another batch of fish will come.
On a good run, you can hear the flopping on the beach. It sounds like popcorn popping.
Q: Any recommended beaches?
A: No, because I don’t want them to be loved too much. The problem with any living thing is that you see a lot of them so you think they are not very valuable. I’m very happy to have people come and watch if they don’t bother the fish.
They’re a coastal fish. They’re exposed to whatever’s coming out of Malibu Lagoon. If the sand is polluted too, the eggs are being exposed to the pollution as well. We don’t want the grunion to have the additional pressure of being caught.
Q: What does your family think when you come home after midnight, smelling of fish?
A: Both of my sons have come out with me. My husband is very supportive, but he has to go to work early in the morning.
It’s the best job. It beats working.