A Shark Named Elvis & Aptos Warm Nursery

Two stories from Sal Jorgensen, PhD.

White shark

Pt 1: We confess. This story kind of snuck in here. Taking place off the Farallon Islands, it actually occurred in the Farallon National Marine Sanctuary, next door to the Monterey National Marine Sanctuary. But, well, since sharks travel far and wide, including Monterey Bay, and it’s such a cool story, we decided to let it stay. Sal, shark specialist at the Monterey Bay Aquarium, shares his story about running into an old friend, a shark friend that is. How cool is that?

Pt 2: White sharks used to be rare in Monterey Bay, but when the warm water Blob arrived, things changed. Sal takes us to the white sharks’ nursery with explanations of why they have taken up residence now in our bay.

SALVADORE “SAL” JORGENSEN is a Senior Research Scientist at the Monterey Bay Aquarium in Monterey, California. His job is primarily a research position studying white sharks in the wild, trying to understand these sharks in California waters, their place in the ecology, and how their numbers are changing.

Sal was born in Seattle, Washington, but he grew up a little bit all over the place – Seattle, California, Africa, Canada and then back to California. At age nine he moved with his family from Canada to Mozambique off the east coast of Africa and lived there for five years. His parents, who were university teachers, participated in Canadian University Overseas, which is like a Peace Corps for university teachers to teach in developing countries. When they returned from Mozambique the family settled in Montreal, Canada. Sal notes that while it is a beautiful inland city, it is an island on a river and very cold in the winter. As a teenager he was counting the days to finish high school and community college and go explore warmer areas that were coastal.

After meandering through Central America and Mexico, Sal ended up in California again and liked it here. He’d always considered himself a West Coast person by birth, and he and his parents lived on the West Coast of North America from southern California to Seattle, Washington to Canada. After living in Africa, he became very much drawn to the ocean.

Sal got his undergraduate degree at Sonoma State then applied to graduate school at the University of California at Davis. At the time he was working at the Bodega Marine Lab, so had already started to put his roots down in the coastal California area.

After graduating with a PhD in Marine Ecology from UC Davis, where he studied the movements and population dynamics of fishes, there was a job offering at the Monterey Bay Aquarium to study white sharks. That was around 2005 when the Aquarium had been the first to successfully display a white shark. A lot of people would come to visit, and the Aquarium saw this as an opportunity to invest extra funds into studying this enigmatic species. Sal was intrigued by the idea of studying white sharks, applied for the position and was hired.

Like every diligent nine year old, Sal had done a lot of research on white sharks and scared his mother a lot. When he first had the opportunity to study sharks as a biologist before getting the position at the Aquarium, he called his mother and said, ”Hey I’ve got this great opportunity to study schooling hammerhead sharks at a seamount in Mexico, and I’m going down with a world-famous shark scientist Dr. Peter Klimley to dive in the water and count the sharks.” There was a long silence on the other end. “Mom, are you there?” “Maybe I could get you some shark repellant,” she replied. He explained that Jane Goodall didn’t wear chimpanzee repellant when she was out in the field.

As a marine ecologist Sal has always been interested in movement, and how movement affects population dynamics, and why animals move. He has studied rockfish movement, and he studied movements of fish around seamounts in the Sea of Cortez in Mexico. Those studies included hammerhead sharks and communities of species such as tunas and jacks. Studying sharks through the Aquarium was a way to continue following this path.

Sal realized during college that he was studying declines. As a kid, he didn’t know and don’t think anyone knew that much about whether we could deplete the oceans. As he started learning about this, he realized it’s a real problem for sharks, because they take so long to reproduce and have so few young that they’ll have a hard time recovering.

Sal notes that the problem with sharks is they have this bad reputation. Getting people behind shark conservation is not as easy as, say, asking people to save the whales.

But Sal’s job at the Aquarium is good because they’re dealing with the white shark, which is kind of a poster child of this perceived threat sharks pose to people. When Sal started the position, he and his colleagues were excited that they were going to learn a lot of new stuff about sharks, and Sal thinks they’ve done just that.

You can watch Sal’s stories on Youtube here: https://www.youtube.com/watch?v=f7k3OmDoFjQ  

A SHARK NAMED ELVIS 

I’m thinking of a story, actually the freshest one in my mind is from this past Friday. But I think it’s a good one, because it kind of tells the whole story about California white sharks that are central to this area, the Monterey Bay area.

On Friday we went out to the Farallon Islands for tagging and doing our photo ID work. The Farallon Islands, Año Nuevo Island, Point Reyes, this whole region of Central California is a spot where white sharks come and aggregate. They’re looking for their prey and October – November is a peak time. Now we’re in the middle of October right in the thick of white shark season.

Sharks are coming here essentially to eat juvenile elephant seals that are hauling out at this time of year. So we were out at the Farallon Islands, and we were photographing the sharks, and we were looking to get a profile shot of the dorsal fin, which is basically their fingerprint.

So we’re fifteen minutes in, and we had a shark up. We use a decoy; it’s a silhouette that looks like a seal. We float that out underwater behind us. And we’re anchored at this point at the Farallons.

We had a shark right up at fifteen minutes in, and we got some video and it was great. We didn’t recognize that shark. And then about mid-morning, we were just about to pull the anchor and go try a different spot. The decoy was already reeled in and in the boat, and we looked down and suddenly see there’s quite a large shark, around sixteen and a half feet long, swimming around the boat. It had lots of scars, you know, and it looked like a real old timer. So we started looking closely and finally the shark surfaces and we can see the fin, and it’s a shark that we call Elvis. We recognize at the tip of the fin it’s got a little flip, sort of a rounded part, like the hairstyle of the legendary singer. So, his name’s Elvis.

Elvis is a real special shark, because Elvis was first photographed at the Farallon Islands in 1989. And so this Friday, we have a new record – the longest span between when a shark was first ID’d and when we’ve subsequently seen him most recently. So it’s twenty-nine years! The previous record was twenty-seven years, which still is impressive, and there’s one at twenty-six years. So it’s incredible!

My colleague, Scott Anderson, photographed this shark in 1989 when he was on the island actually studying birds. That was before he shifted his lens from the birds over to the ocean and started studying the sharks and came over to this side, where he really started this photo ID program.

A lot of the ID photos we’re looking at today, we’re going back to match to some of these historical photos. It’s been twenty-nine years and in that time, I’ve seen Elvis…the last time I saw him was two years ago in 2016. And then, I think in 2015, 2014, and then 2013 and 2011. In 2006 I remember seeing him. Not every year, but we see him out there frequently and it’s really exciting.

What it tells us really illustrates the story about white sharks in this area. These sharks come back here every single year.  The males every year, the females every other year, or sometimes they take a break, but basically throughout the whole of their life. Where they go between seal hunting seasons is offshore to the White Shark Café, over to Hawaii. It takes about a month to swim out there. But just like clockwork, they come back every year. It’s just amazing to see the same individuals come to the exact same spot. We could have been anchored there ten or fifteen years ago in the exact same spot and seen Elvis.

And if we didn’t have our satellite-tagging program, you would think that these sharks never left that exact same tiny little area. But when we started putting on electronic tags, we just saw the tracks head off into the ocean. In fact, they spend more time offshore in the open ocean than they do at the coast, but they come back every time.

The reason why this is so significant is that these sharks are able to cross, traverse the ocean. They swim to Hawaii regularly; they could clearly just keep on going to the other side. There are white sharks on the other side. But they come back. They’re kind of like salmon. Salmon go and give birth where they were born. And that’s why they have these genetically distinct stocks of salmon. Some of them are distinct within a particular fork of the same river.

Well, we have our white sharks here in California and northern Baja. In this, what we call the northeastern Pacific, they are genetically distinct from all other white sharks in the world. And we think the reason is because of this site fidelity, philopatry[1], love of place, so there’s a tendency to go give birth where you were born.

So Elvis is a male, obviously, but the females are doing the same thing, and the females will come and give birth in southern California and northern Baja. So, that’s pretty cool.

APTOS WARM NURSERY

One of the really cool, interesting new things in Monterey Bay, with regards to our white sharks, is since 2014 we’ve started to see a lot of small sharks in Central California that we‘ve never really seen before, in particular, in the northern part of Monterey Bay off of Aptos and New Brighton Beach.

We first started seeing this around 2014, and we’ve done some work looking at the types of temperatures that these smaller sharks prefer, because white sharks are endotherms, and they have to maintain a warm body core temperature. Usually, when they’re born they’re confined to warmer waters. In California, that means south of Point Conception, so the Southern California Bight.

However, in 2014 we had this warm ‘Blob’, a body of warm water that really warmed up the coastal waters in Central California. In 2015 we had El Niño, which extended to 2016, so there was three or four years in a row of exceptionally warm waters in Central California. When we plotted where we would expect to see juvenile white sharks and newborn white sharks, according to the water temperature, suddenly the area that should be accessible to them was above Point Conception, into Central California and even up to Monterey Bay. And so theoretically, looking at the temperatures we could predict that they should be in Monterey Bay, and that coincided with the observations that indeed we started to see up here.

Even this year, they’re back again. So, we’re trying to figure out what exactly is going on. We think that it’s clearly a temperature related phenomenon to see them up here. We think that this might become the new normal, certainly twenty to fifty years from now as the ocean temperatures warm, this will happen more frequently. This was what we predicted, and it may, in fact, eventually be just warm enough for these juvenile white sharks to be up here.

The interesting thing is, it’s only warm here part of the time, part of the year. In the spring we get the winds and it stirs up the water. We get the upwelling, we get the cold deep water coming up to the surface. And so our entire coast starts to get a lot chillier.

But there’s this really interesting pattern that happens, because the northern part of the bay is hooked over and it’s south facing, and it gets a lot of sunlight and the current that’s running along shore, along the California coast, kind of has a little eddy into the northern part of the bay.

As the water temperature cools off along Central California in the spring, there’s always this warm pocket of water inside the bay right off of Aptos. And we’ve worked out to see when this warm pocket is prominent and what the temperature differences are. And I’ve seen this spring that the temperature difference between that warm pocket and the outer waters of say Año Nuevo, can be a 5-10 degree difference. And that’s a huge amount for a small-bodied animal that has to stay warm.

You know, people have been seeing a lot of sharks off of Aptos and wondering why there are so many in that one particular area. And we think that what happens is, you know, we have these abnormal warm years. Water generally in southern California is fairly warm, so the sharks can come up here, or maybe they’re even born here, because the mother recognizes it’s a warm enough area. Then the wind blows, the area cools off, and everything starts cooling except for that one warm spot.

We think this has the effect of corralling all those sharks into that area. That’s the hypothesis that we’re working with right now. We’ve been out there this spring putting on tags that measure temperature, that have video cameras that record their behavior and record the types of things that they’re seeing.

The interesting thing is that these little white sharks, when we see them in Aptos, are swimming at the surface. They’re kind of basking in the sun. It’s the warmest spot. We can tell from our tags, this is the warmest time of the day and this is the warmest place to be that they’ve found. And that’s when they linger around.

Typically when we see white sharks in a hunting mode or a foraging mode, they’re typically swimming deep, and they’re not looking to be detected, so they’re trying to be stealthy and use the element of surprise to come up on a seal or sea lion or something. We don’t think that the surface milling is a predation behavior. We think it’s a thermoregulatory behavior.  Indeed, it supports the idea that they’re trying to stay warm. The way to do that is to be in the warm spot, not only that, to be right at the surface and getting some solar radiation in that little warm layer of water. That spot’s not getting much wind either. It’s really windy outside, but you duck into that little cove, it’s just so calm and warm. If you’ve gone there from Monterey, you can really feel the difference, as you know.

So that’s a pretty interesting new development. You know, it’s a changing place, and we’ve seen since 2014 a lot of new species up in this area – different birds, snails, pelagic crabs, all this new stuff associated with warmer water. I think the smaller juvenile white sharks are just one more piece of that puzzle.

[1] Tending to return to a particular site or area.