A fatal shark attack in Wellfleet last weekend has left a lot of questions – about preparedness and response protocols – and also about the sharks themselves and how to stay safe. WCAI's Kathryn Eident talked with Living Lab Radio Heather Goldstone about shark behavior.
Eident: So, Heather, we know this, we've been talking about this quite a bit. There's been two attacks so far this year and actually quite close together with one just last weekend and another less serious--not fatal--a little earlier this summer. Why now?
Goldstone: As you know, a lot of people have, not in a good way, but been almost waiting for this, saying for the past few years that at some point, this could turn fatal as the numbers have risen. But, I think in the wake of these attacks there's also been a lot of speculation and some rumors and you know, "what's going on with this?"
So, I spoke with the state's lead shark biologist, Greg Skomal, from the Division of Marine Fisheries, and ran through a lot of those, and he said that in his mind, it really just comes down to the simple math and the growing number of sharks in our waters.
Eident: Let's take a listen to something from Greg here.
Skomal: "I don't think the behavior of the sharks is changing, or shifting, or evolving. I think what they're doing is they're showing up in greater numbers along this shoreline."
Goldstone: And of course, those sharks are on our shorelines because they're looking for seals, which we've also seen increasing numbers of seals in recent years. But, there are a lot of people using those same shorelines and Skomal says that these sharks who are looking for food are often making split-second decisions, often in low visibility conditions, and it's not always clear whether they're going for a seal or a human.
Eident: Really it's not a case of mistaken identity? There's video that Greg Skomal is in with a shark jumping up out of the water. What's going on?
Goldstone: Yeah I know, and that's that's part of the speculation is whether or not these sharks really are just mistakenly attacking humans. And Greg says that despite all of that speculation, despite the fact that a shark did jump out of the water to try to bite the boat that he was on earlier this summer, in the vast majority of cases, it does appear to be a case of mistaken identity, where the sharks think that they're going for a seal and that in fact, if you look more broadly in the research of shark attacks, there's really no evidence to support the idea of sharks becoming man-eaters and actually targeting humans as prey.
Eident: And then another thought too, is how close can sharks come to shore? Because these folks were fairly close.
Goldstone: Yeah. And you know, it's interesting. Skomal says we really need to actually change the way we think and talk about the risk and these attacks. That it's not about how close they are to shore. When you're thinking about it from a shark's perspective, they are looking for food.
And, really the limiting factor is depth, not how close they are to the shore. The Cape has some pretty unique topography; off the beaches, these ridges of sand underneath the water as you go off the beaches-- the sandbars that people like to play on--and in some beaches, that means actually that it drops off pretty quickly and comes back up to a sandbar. But, you've got some pretty deep water close to shore, and that can be a factor in the sharks coming in closer. So, he says he doesn't like to give advice, or set the depth limit, but for himself, he only swims in water that's about waist deep. Let's hear from Skomal again.
Skomal: "A shark typically won't go into water much less than six feet deep because it runs the risk of going aground, particularly when you're talking about areas of high surf or swell or current."
Goldstone: He also notes that this is kind of late in the season, that seals have been learning ways to avoid the sharks all summer, maybe coming closer into shore. And, that as it gets later in the season, the sharks may also be getting a little bit more willing to challenge their own comfort zones, and they may be coming into shallower waters, as well.
Eident: That sounds like in some ways it's a learning experience for everybody involved--humans, seals, and sharks. Now, of course, these happened on the Outer Cape, but we've heard some of sightings elsewhere along the shoreline. So, they're everywhere.
Goldstone: Well, yeah. So, they are around--just this week we've heard about this sighting potentially in Wareham, not sure about that one a few weeks ago. There was what's considered to be a credible sighting near Penikese Island at the mouth of Buzzards Bay. But, Skomal says that they do have receivers in all around Massachusetts waters listening for the tags that they've put onto a lot of these sharks. They're getting more reports from in Cape Cod Bay along the inner edge of Cape Cod, down the Wellfleet shoreline there. But, for the most part, where they are seeing these sharks is along the Outer Cape, and that that hasn't really changed in a couple of years that they've been tracking them.
Eident: Well, so much more to learn and observe as we go forward. Heather Goldstoneis our science correspondent, also host of Living Lab Radio and you can hear her full conversation with Dr. Greg Skomal state biologist, on Monday at 9:00 a.m. here on WCAI.
This transcript has been lightly edited for grammar and clarity.