Air Date: Week of March 9, 2018

A mother North Atlantic right whale and her calf off the coast of Florida. This year’s apparent lack of any newborn North Atlantic right whale calves could spell disaster for the critically endangered species. (Photo: FWS Fish and Wildlife Research Institute, Flickr CC BY-NC-ND 2.0)

It’s long been illegal to hunt Northern Right whales, but this endangered species’ population is still declining. After an unprecedented number of deaths among the North Atlantic Right whales last year, no new births have been recorded so far this year either. Regina Asmutis-Silvia of the North American branch of Whale and Dolphin Conservation discussed this ecologically critical species and prospects for its future with Living on Earth’s Jenni Doering.

Transcript

[SOUND OF RIGHT WHALE CALLING]

CURWOOD: Northern Right whales have reason to sound mournful. They’re lonely.
Though it’s been illegal to hunt them since 1935, the numbers of this favorite target of the whaling industry are down to about 450 and moving ever closer to extinction.
The warming ocean has prompted them recently to move north from their usual summer feeding grounds in the Gulf of Maine into Canada’s Gulf of Saint Lawrence. Canada has fewer rules protecting them from ship strikes, and some eighteen of these rare giants died this past season alone. And now comes a report that this already critically endangered population has produced no new calves in the past year. To learn more, Living on Earth’s Jenni Doering spoke with Regina Asmutis-Silvia, of the non-profit Whale and Dolphin Conservation.

DOERING: So Regina Asmutis-Silvia, why do we think that there have been no Right whale births this year off the coast of the US?

ASMUTIS-SILVIA: So, Right whales are an intensely studied species because they are so critically endangered, there are a number of dedicated surveys that happen in what has been their dedicated calving area. And there haven't been...there have been very few whales who have shown up there, none with calves, and there's also intensive surveys that are happening in Cape Cod Bay which is another winter, early spring habitat for them, and there's been no calves sighted in that area as well.

DOERING: How unusual is this?

ASMUTIS-SILVIA: It's unprecedented. We've never ever ever had a year we didn't have a single calf born to the population.

DOERING: And how many whales are in the population as a whole?

ASMUTIS-SILVIA: Probably between 430 and 450 at best.

DOERING: But I understand, like not a lot of those are females, right?

ASMUTIS-SILVIA: No, so unfortunately because of human impacts the population impacts have been more harmful to females at this point, so there's probably only about 100 breeding females left.

DOERING: Why is that? Why are the females suffering more?

ASMUTIS-SILVIA: We always do? [LAUGHS] It's a good question. I mean, I think that they tend to be more coastal, oftentimes they tend to spend a lot more time at the surface particularly if they're having calves. So, they're in areas where if they get pregnant, they need to feed more. So, I think that they're more susceptible to a lot of human impacts just because of their life history, what they need to go through, so that they just tend to be in more risky areas.

DOERING: So, if you tell me a bit more about like why would they not be having any new calves this year. What could be affecting that?

ASMUTIS-SILVIA: I think it's a combination of things. It's not one particular issue, but the biggest issues that they're facing right now are fishing gear entanglements and vessel strikes, but we know that even if they can survive a fishing gear entanglement that there is what is referred to as a sub-lethal effect, and so the stress that entanglement put them under then causes a lot of stress to their body, increase in stress hormones that makes it a little bit harder for them to get pregnant or to carry a pregnancy to full term. That's one issue.

The other thing is that they may not just be getting fat enough as climate is changing and their food resources are moving around and they're looking for maybe alternative food. It might not be as healthy for them, it might not be make them as fat as they should be, and so females have to eat to get really really fat to be able to produce those hormones that allow them to ovulate, so it's probably a combination of those things.

DOERING: So, let's talk a little bit about why – why is this important. Why does this matter on a larger scale, and what role do Right whales play in the environment?

ASMUTIS-SILVIA: My favorite thing to talk about is that whales are an incredibly important part of our ecosystem and there is emerging research that’s coming out in confirming that they play this incredibly important role as the ocean gardener. So, we need phytoplankton, the planet, humans, we need phytoplankton and that produces half of our oxygen, it is the base of the marine food web, it sustains fish stocks, it takes in carbon dioxide when it photosynthesizes, and so it sequesters carbon, it fights climate change. So, we need phytoplankton and what phytoplankton need are whales because they can't root into the soil, so they can't get their nutrients the way that a plant on land would, so you need the nutrients brought to them and that's where whales come in.

So whales are great at diving and they can do lots of things deep, but what they can't do when they're at depth is they can't poop. So, bathroom breaks are all at the surface and, it's the bathroom breaks that are fertilizing phytoplankton at the surface. So, that's where they get phosphorous and iron and all the things that they need, so they literally are tending this forest in the ocean that we need to survive. So, if we need phytoplankton and phytoplankton need whales, then we need whales and Right whales along with a lot of other whale species play that really integral role.

DOERING: And they're not eating the phytoplankton directly right? What are they feeding on?

ASMUTIS-SILVIA: So, for North Atlantic Right whales, they're feeding on a different kind of plankton, zooplankton. It's a tiny little animal called the copepod, and so the copepods are grazing on the phytoplankton. So, they're eating these tiny little animals which also kind of free float around at the surface and they require ocean currents to kind of concentrate them to a point where the Right whales can feed on them, so Right whales are very dependent on a healthy climate and a healthy planet to be able to do their job because they need these physical parameters to concentrate their food for them.

DOERING: You talked about how entanglements in fishing gear is really hurting these whales and making it more difficult for them to get pregnant. What kind of gear is that and why does that happen? Why do they get tangled up?

ASMUTIS-SILVIA: So, primarily what they're getting entangled in is the kind of gear that we refer to as a fixed fishing gear, and it's gear that set out there and left to fish and then retrieved at another point - lobster, crab, gillnetting, hagfish - those are I think the things that people are more familiar with in this area where all those pretty colorful marker buoys that you see at the surface off the coast are marking some vertical line that's at the bottom attached to a trap, and certainly the snow crab fishery in Canada is where there were a lot of entanglements last year. And I think it's incredibly important to clarify that this is not intentional. Fishing gear has been changing and evolving and so that ropes that used to be made of hemp or natural fibers which might have deteriorated a little bit more quickly are now being made out of plastic polymers and so that they're more sturdy for the fisherman, but that means that they're stronger and they're more sturdy when the whale gets entangled into them too, and there's no evolutionary adaptation that says that they should be worried about this.

So, they're in places, they're doing what they're supposed to do, they're socializing, they're feeding, they're chatting, they're doing whatever, and they will bump into gear. What they seem to do though is that they roll into it. It's kind of like they choose the path of least resistance, so if it doesn't - and I'm speculating here - but if it if it doesn't feel good when you're pulling against it then roll, and maybe you're not pulling against anymore but now you've become even more entangled in it. So, they do tend to roll into the gear. That exacerbates the entanglement. It's really really strong, long-lasting like I said, plastic kind of lines that they're getting in tangle in that aren't going to deteriorate in any way, shape or form and so now six months later they've got a piece of gear that's literally either acted as a tourniquet and cut off a blood supply, sawed into tissue or bone, resulting infections will kill them, and it's a really horrible way to die.

DOERING: In the past year, Regina, 18 North Atlantic Right whales were found dead, 12 of which were found as far north as the Gulf of St Lawrence and Canada. And how is the lack of right whale births this year connected to this unprecedented death rate that we saw this past year?

ASMUTIS-SILVIA: It's devastating. If you want to recover an endangered population, you need to recruit more than you kill. So, if you had 18 die then you need more than 18 born to even try and just mildly offset that, so to have 18 dead and then no calves born is really definitely adding another nail to the coffin.

DOERING: So, you mentioned climate change is causing their food source, copepods, to move around. How much understanding do we have of that movement and what do you think the whales know?

ASMUTIS-SILVIA: Whales know a whole lot more than we do. I mean, certainly their distribution changing is telling us that they know a whole lot more than we do. So, if they're not finding what they want where they used to get it, they're going someplace else to look for it. We have no idea how they find their food, not a clue. So, we don't know if it's an acoustic detection, we don't know theoretically...they don't have this great olfactory functioning, but I don't know that we really understand all that that well either. So, whatever senses that they're using to find food, they're way better at that than we are.

The studies that have been done by the Center for Coastal Studies in Cape Cod Bay show that they won't even open their mouths if that concentration of copepods isn't enough. How they figure that out, we don't know, but they - the copepods that they feed on are typically what they're feeding on in the Gulf of Maine are very temperature dependent, and so if there are having issues with the Gulf of Maine warming faster than the rest of the North Atlantic, those concentrations of that particular kind of copepod seem to be diminishing. There's researchers at Dalhousie University that are looking at the copepods that they're feeding on in the Gulf of St Lawrence and it's a different species, it's an Arctic species and somehow they've figured out that it's there, and that that's an alternative food source for them.

DOERING: Do you see hope for next year? You know, do you see this population recovering?

ASMUTIS-SILVIA: I always see hope. I can't fathom that we would allow them to go extinct. I mean, we did this, we can undo it. So, I think we just have to figure out and be creative and be thoughtful, and everybody has to kind of pull together to do it. And then there is a lot of work being done with Woods Hole right now trying to look at how to develop gear that doesn't have that vertical line in the water.

There is the National Marine Fishery Service is holding some subgroups that are trying to look it either implementing ropeless gear or a weaker line gear. We've already done sort of a good job a little bit I think in the US with reducing ship strikes. We need to do that in Canada. And I think that there's hope and I also think that’re not our whales, they belong to everybody, we all need them. So, that means that everybody has a say in this, and everybody has something they can do, and so if we know that a change in climate is a problem then everybody collectively can do something to help with that too. So, those sort of old adages about recycling and reusing, they add up, and they are meaningful. So we all have a stake in this.

CURWOOD: Regina Asmutis-Silvia is senior biologist with Whale and Dolphin Conservation. She spoke with Living on Earth’s Jenni Doering.

 

Links

The Boston Globe: “After year of record deaths, right whales produce no new calves, which could be ‘catastrophic’”

Whale and Dolphin Conservation homepage

NOAA, “Sounds in the Ocean”