Speaker 1: Hey, you welcome to Stuff to Blow your Mind. My
Speaker 1: name is Robert.
Speaker 2: Lamb and I am Joe McCormick, and it's Saturday. Time
Speaker 2: to go into the vault for an older episode of
Speaker 2: the show. This is Part three of our series on
Speaker 2: the gray whale. Parts one and two aired on Tuesday
Speaker 2: and Thursday of this previous week. This episode originally published
Speaker 2: on March ninth, twenty twenty three. I hope you enjoy.
Speaker 3: Welcome to Stuff to Blow Your Mind, a production of iHeartRadio.
Speaker 1: Hey, welcome to Stuff to Blow your Mind. My name
Speaker 1: is Robert Lamb.
Speaker 2: And I'm Joe McCormick, and we're back with Part three,
Speaker 2: the final part in our series on gray whales. Now
Speaker 2: in the previous episodes, which if you haven't listened to yet,
Speaker 2: you should probably go back and check out parts one
Speaker 2: and two. First, in the previous ones, we described the
Speaker 2: morphology and behavior of the species scientific name Eschrichtius robustus,
Speaker 2: the robust buddies, the grey whales, and we talked about
Speaker 2: their relationship with the barnacles that often pile up on
Speaker 2: them like a like a big old nasty crust. And
Speaker 2: we talked about their relationship with their main predator other
Speaker 2: than humans, the orca uh. And today we're going to
Speaker 2: kick off addressing their amazing migratory habits, which is probably
Speaker 2: one of the main things to understand about this species.
Speaker 1: Yeah yeah, And to sort of draw back to those
Speaker 1: previous episodes that reiterate that I did get the chance
Speaker 1: to see grey whales in the wild at their breeding lagoons,
Speaker 1: a particular one of their breeding lagoons called Ojo de
Speaker 1: Labra Lagoon on the Baja Peninsula about halfway down the
Speaker 1: Baja Peninsula, and it was an amazing experience. So I'll
Speaker 1: refer back to to some of my observations alongside thevarious
Speaker 1: sighted materials that we're going to be referring to now.
Speaker 1: Speaking of those breeding lagoons, in the last episode, we
Speaker 1: mostly discussed these as the safe waters for the birth
Speaker 1: of the whale calves and a reason for migration in
Speaker 1: gray whales in particular. But as highlighted in one of
Speaker 1: the books that I was using here, whales their biology
Speaker 1: and behavior by Hammond at all, there are other considerations
Speaker 1: to take into account concerning first of all, just migration
Speaker 1: of balen whales in general. So on the reproductive front, yes,
Speaker 1: protection from orcas does seem to be a major factor,
Speaker 1: particularly with gray whales, and there's the additional hypothesis that
Speaker 1: the whale calves to survive and grow better in warmer waters.
Speaker 1: It's also argued that it's simply energetically more efficient to
Speaker 1: swim to warmer waters than to overwinter up north. There's
Speaker 1: also more visibility and shelter in tropical waters. We talked,
Speaker 1: and this comes back to orcus survival to a large extent,
Speaker 1: gust the gray whales ability to seek shallower waters. And
Speaker 1: part of that is that there it sounds like they're
Speaker 1: just more nooks and crannies that the whales may venture
Speaker 1: into to find refuge. Yeah.
Speaker 2: So, for example, when gray whales are threatened by orcas,
Speaker 2: it's been observed that they might try to seek shelter,
Speaker 2: say in kelp beds, or like in hiding in seaweed,
Speaker 2: or even in breaking surf, which apparently helps obscure their presence.
Speaker 1: Yeah, and we'll come back some more details about this
Speaker 1: in a minute. The authors here do stress, however, that
Speaker 1: there's just there's no one size fits all explanation, especially
Speaker 1: considering that there are various differences in behavior among the
Speaker 1: balen whales in general. For instance, they mentioned that one
Speaker 1: factor for many balen whales, again not grey whales specifically,
Speaker 1: but other filter feeding whales, seems to be that during
Speaker 1: the summer you have a stratification of the water column
Speaker 1: to include a highly photic zone, resulting in rapid photosynthesis
Speaker 1: and reproduction of phytoplankton. Phytoplankton are the plant plankton, and
Speaker 1: these phytoplankton in turn feed the zooplankton, which of course
Speaker 1: are the animal plankton, and this generally fattens up the
Speaker 1: entire ecosystem in these waters. But then in the winter,
Speaker 1: cooling temps and strong winds break up the stratification, mixing
Speaker 1: the vertical water column. Phytoplankton can't stay near the surfaces easily,
Speaker 1: there's increasingly less sunlight, and prey availability takes a dive
Speaker 1: as well.
Speaker 2: Okay, so the plankton scene kind of dries up a
Speaker 2: little bit.
Speaker 1: Yeah. Now, as we mentioned, and I believe the first episode,
Speaker 1: gray whales are of course rather different than a lot
Speaker 1: of the other baileen whales, I mean, all the other
Speaker 1: extent baalen whales, because they're not really going after things
Speaker 1: like kelp and zooplankton. No, they're going after those benthic
Speaker 1: organisms like isopods in the sand on the seafloor, so
Speaker 1: they're not directly feeding for the most part on plankton. However,
Speaker 1: the benthic organisms down there are still part of the
Speaker 1: food web and are therefore impacted as well by all
Speaker 1: of this.
Speaker 2: Okay, so if you don't recall, we described their typical
Speaker 2: feeding behavior, I think in part one of this series,
Speaker 2: where unlike the whales you've probably seen kind of like
Speaker 2: zooming around near the surface of the water and just
Speaker 2: like letting water wash into their mouths and filtering out
Speaker 2: all of the plankton or the krill or whatever with
Speaker 2: their billion, the gray whales have a habit of slamming
Speaker 2: their heads into the sediment on the ocean bottom in
Speaker 2: relatively shallow areas to sort of like scoop up a
Speaker 2: bunch of this sediment and then get use their billion
Speaker 2: to filter the organisms out of it and eat those.
Speaker 1: Yeah, exactly like basically scraped in one side of their
Speaker 1: face across the sea floor. Now there's another interesting factor
Speaker 1: in all this. So we mentioned in one of the
Speaker 1: previous episodes that grey whales have been observed in recent
Speaker 1: years overwintering in the Arctic and not making the migration
Speaker 1: down south in rare instances. And I don't believe we're
Speaker 1: talking about reproductive or currently reproducing females in these cases.
Speaker 1: But basically this is a situation where we have to
Speaker 1: consider climate change once again. We have to remember that
Speaker 1: climate change has some of its more drastic effects in
Speaker 1: the Arctic. And I was reading and interesting NOAA paper
Speaker 1: dealing with some of this, titled Sentinels of Change Gray
Speaker 1: Whales in the Arctic, pointing out that less sea ice
Speaker 1: means more exposed ocean areas, and this alone has a
Speaker 1: huge impact on the environment. But they also point out
Speaker 1: the following. So in cold years, what you have happening
Speaker 1: first is a spring bloom of plankton. But in the
Speaker 1: early spring, most zooplankton are not yet ready to graze. Meanwhile,
Speaker 1: the phytoplankton, the plants digging all that sunlight, they're just
Speaker 1: going crazy, and there's so much of it that the
Speaker 1: zooplankton are not in. The zooplankton are not ready to
Speaker 1: feed on it yet, so most of it ends up
Speaker 1: sinking to the bottom. And what happens at the bottom, well,
Speaker 1: that's where the benthic organisms are and they feast on them.
Speaker 1: And again that is what the gray whales are primarily
Speaker 1: going to eat, those creatures down there that just date
Speaker 1: all of this phytoplankton. In warmer years, however, the sea
Speaker 1: ice melts too early, there's not enough light to really
Speaker 1: power up the spring bloom of phytoplankton, and so the
Speaker 1: phytoplankton bloom is delayed and it doesn't really hit until
Speaker 1: oh the zooplankton is fully ready to feed, meaning that
Speaker 1: the zooplankton can eat most of it. There's less to
Speaker 1: rain down to the benthic organisms.
Speaker 2: Okay, so that sounds not great for grey whales.
Speaker 1: That's what it would sound, right, yeah, because that's their
Speaker 1: primary feast down there. But what this particular paper stresses
Speaker 1: is that as warmer years likely continue due to climate change,
Speaker 1: we might see gray whales shift in their diet. So
Speaker 1: we mentioned that they're fairly opportunistic, so they will do
Speaker 1: some filter feeding in the upper portions of the of
Speaker 1: the water. So if they aren't able to get what
Speaker 1: they would normally get down there at the bottom, or
Speaker 1: it seems like there's more, say zooplankton in the upper
Speaker 1: portion of the water column. Then they will eat that
Speaker 1: and potentially eat that instead. So it's a situation where
Speaker 1: they outline that a couple of things might happen. We
Speaker 1: might just see them displaced from their traditional feeding grounds,
Speaker 1: but we also might see a portion of their diet
Speaker 1: shift more in favor of filter feeding upwards in the
Speaker 1: water column, eating more zooplankton than would normally make up
Speaker 1: their diet. And I think, goodness, I'm trying to remember
Speaker 1: what the percentage was when we talked about it, but
Speaker 1: it's like a huge percentage of their known normal diet
Speaker 1: is those benthic organisms down there in the sand. So
Speaker 1: it's kind of a good news not I don't know
Speaker 1: if it's a good news bad new situation, but anyway,
Speaker 1: it's weeks to These organisms have been around for a
Speaker 1: long time, and part of their ability to survive has
Speaker 1: been their ability to make reasonable adaptations.
Speaker 2: Yes, And I guess that brings us back to the
Speaker 2: issue of the migration, because what we're talking about right
Speaker 2: now is primarily what's happening in their feeding grounds in
Speaker 2: the Arctic waters, but that's only half of the story.
Speaker 2: That's where they fatten up up north, especially when we're
Speaker 2: talking about this population of the Eastern Pacific gray whales.
Speaker 2: The other half of the story is reproduction, which involves
Speaker 2: a journey south.
Speaker 1: That's right, and this is quite a journey for the
Speaker 1: gray whales. The distance between their summer feeding grounds and
Speaker 1: their winter breeding grounds can exceed twenty thousand kilometers. That's
Speaker 1: something like four hundred and twenty seven miles. Now, it's
Speaker 1: worth discussing again again. These are not deep ocean whales,
Speaker 1: and that makes sense given their diet. They primarily stick
Speaker 1: to shallow continental shelf waters. They stick reasonably close to
Speaker 1: the coast, and therefore we see that reflected also in
Speaker 1: the way they migrate between these two waters. They're not
Speaker 1: making a beeline from one area to the next. Their
Speaker 1: journey tends to be more coastal, with some alterations depending
Speaker 1: on exactly whe their circumstances are. Now, we mentioned that
Speaker 1: there used to be a population of North Atlantic gray whales,
Speaker 1: and it's thought that they would have fed around Newfoundland,
Speaker 1: the Gulf of Saint Lawrence, Iceland, and Europe's North Sea.
Speaker 1: And it's thought that they would have found winter breeding
Speaker 1: refuges somewhere along the coasts of Georgia and the Carolinas
Speaker 1: here in the States, as well as uncertain spots along
Speaker 1: the coasts of Spain, Portugal, and Morocco. Now, this population
Speaker 1: was essentially extinct by the late seventeenth and early eighteenth centuries,
Speaker 1: due at the very least in a large part to whaling,
Speaker 1: if not largely to whaling or entirely to whaling. Interestingly enough,
Speaker 1: there have been proposals to try and reintroduce specific gray
Speaker 1: whales into this region to restore the population. I think
Speaker 1: we mentioned this previously. And there's also the possibility that
Speaker 1: they may recolonize the area themselves as in the future
Speaker 1: as sea ice melts and opens up these waters to
Speaker 1: them once again. So the North Pacific population potentially recolonizing
Speaker 1: the North Atlantic, But that's kind of hypothetical. We're not
Speaker 1: sure exactly how that would pan out, though.
Speaker 2: I guess it's always possible, because occasionally you do find
Speaker 2: whales like way outside of their normal ranges, right, They
Speaker 2: just kind of pop up in strange places that you
Speaker 2: don't usually find them.
Speaker 1: Yeah, there are a couple of outstanding examples of that
Speaker 1: that Carbonine points out. A single gray whale was sighted
Speaker 1: off the coast of Israel in twenty ten and in
Speaker 1: twenty thirteen, one was seen off the coast of Namibia,
Speaker 1: and it's uncertain exactly why. In both of these cases,
Speaker 1: the Hammond at All point out that their origin was
Speaker 1: almost certainly the North Pacific population in both cases.
Speaker 2: Though, yeah, that's great. How would they get that far away? Yeah,
Speaker 2: I mean, I guess we know they can swim away
Speaker 2: as due to their to their habitual migrations. But yeah,
Speaker 2: you want to know the story of that wandering whale.
Speaker 1: Yeah, now, now coming back to that now extinct North
Speaker 1: Atlantic population. Quick Outlander note out for everyone out there.
Speaker 1: I was reminded of this. My wife reminded me that
Speaker 1: we had watched this. But the television series adaptation of
Speaker 1: Outlander has a scene set on the coast of South Carolina,
Speaker 1: and again this is about time travelers going back in time,
Speaker 1: in which two of our time traveling characters remark about
Speaker 1: some whale activity off the coast and how they wouldn't
Speaker 1: have seen this in their original timelines or in the
Speaker 1: original times, and the footage they use in the show,
Speaker 1: I had to check it. It's not gray whales that
Speaker 1: they're they're using here, I believe, but it certainly made
Speaker 1: me think of this scenario that you're like, Yeah, if
Speaker 1: you went back in time before human whaling activity seemingly
Speaker 1: had a chance to just drastically alter the the ecosystem
Speaker 1: in the Atlantic, you would have potentially seen these great whales,
Speaker 1: Like it would have been possible for me to see
Speaker 1: gray whales in my home state of Georgia potentially without
Speaker 1: having to travel to the other side of the continent
Speaker 1: and then to another country.
Speaker 2: And when is this said an outlander? Is this like
Speaker 2: early eighteenth century or something?
Speaker 1: Yeah, the initial transplant I think is from nineteen forty
Speaker 1: five to seventeen forty three. Okay, okay, yeah, And certainly,
Speaker 1: as we'll discuss, given the population changes in the gray whale,
Speaker 1: like nineteen forty five, it was a bad time for
Speaker 1: the great whale anyway. This also reminded me of something
Speaker 1: that our previous guest on the show. This, I think
Speaker 1: was while you were out, Joe, I talked with Ryan
Speaker 1: Tucker Jones, author of the book Red Leviathan, which is
Speaker 1: largely about Soviet whaling in the Industrial Age, but it
Speaker 1: also discusses just the history of whaling in general. In it,
Speaker 1: it's a fascinating look at like why the the Soviet
Speaker 1: Union got increasingly into whaling during the Industrial Age, and
Speaker 1: the impact of it, what was also learned scientifically from it.
Speaker 1: And there's a bit in that. This is just from
Speaker 1: the introduction where he writes, quote, as someone who grew
Speaker 1: up in Oregon and California in the nineteen eighties, I
Speaker 1: experienced the ocean at the whale's lowest point, an ocean
Speaker 1: that had been created by the Soviet Union as much
Speaker 1: as anyone. The history of Soviet whaling belongs to anyone
Speaker 1: who looks out to the sea and sees nothing. Ooh. Yeah,
Speaker 1: there are a lot of really haunting moments in the
Speaker 1: book and just a lot of great details. Certainly go
Speaker 1: back and listen to that interview for more, or just
Speaker 1: check out the book. Just a reminder that the grey
Speaker 1: whale in particular was hunted near the point of extinction
Speaker 1: by humans. We slaughtered them on their migration routes, We
Speaker 1: slaughtered them in their northern feeding grounds, and we slaughtered
Speaker 1: them in their breeding lagoons. They were afforded full protection
Speaker 1: in nineteen forty six, though Soviet whalers took three hundred
Speaker 1: and twenty under scientific permit in nineteen sixty, along with
Speaker 1: another one hundred and thirty eight illegally. These figures according
Speaker 1: to Carwodine in Carwadine Just in case you don't remember,
Speaker 1: I haven't cited him in this episode, but that's Mark
Speaker 1: Carwodine's Handbook of Whales, Dolphins and Porpoises of the World.
Speaker 1: But adding more context from Jones here, he notes that
Speaker 1: by the end of the classical age of whaling, so
Speaker 1: the pre industrial sailing age of whaling, the sort of
Speaker 1: moby Dick era of whaling quote, humans mainly Americans, had
Speaker 1: reduced Pacific gray whales from around twenty four thousand to
Speaker 1: a remnant population of two thousand. Atlantic grey whales were
Speaker 1: entirely extinct.
Speaker 2: And so from what I understand today, Atlantic grey whales,
Speaker 2: they are gone for all we know. And then there
Speaker 2: are the two populations. There is the Western Pacific grey whale,
Speaker 2: which lives along the eastern coast of the Asian mainland.
Speaker 2: That population is, from what we can tell, in pretty
Speaker 2: rough shape today. I don't remember how many individuals it's
Speaker 2: down to, but it's estimated to be pretty low. Whereas
Speaker 2: the Eastern Pacific gray whale, along the coast of North America,
Speaker 2: is doing okay.
Speaker 1: Yeah, And in terms of the classical and industrial whaling, like,
Speaker 1: certain species were impacted more in different in different phases.
Speaker 1: So the gray whales were slower, and they tended to
Speaker 1: be closer to shore, so in many respects they were
Speaker 1: easier to catch during that classic age of whaling, though
Speaker 1: like we mentioned, they were the devilfish. They could certainly
Speaker 1: put up a hell of a fight as well. But
Speaker 1: as the age of industrial whaling brought many of the
Speaker 1: faster species like blue whales and fins into the sort
Speaker 1: of whaling fold, here those whales had fewer defenses against whalers.
Speaker 1: They'd really only ever had to contend with Orca Jones rides.
Speaker 1: But meanwhile, in the age of industrialized Soviet whaling quote,
Speaker 1: gray whales were particularly tricky. Soviet whalers noted that despite
Speaker 1: being slow, the gray was the only whale and he
Speaker 1: quotes about which no rules of catching have been established.
Speaker 1: Only on rare occasions did grays move in a straight line,
Speaker 1: instead usually swimming in zigzags, making movements to one or
Speaker 1: the other side without determined direction. Science the Soviets hoped
Speaker 1: might help establish some or other pattern to its movement.
Speaker 2: I wonder if the ways that different whales react to
Speaker 2: reacted to threats by human whalers was affected by the
Speaker 2: different strategies these species had for dealing with orca. Obviously,
Speaker 2: the threats posed by human whalers and orca are going
Speaker 2: to be of a very different shape and nature. But
Speaker 2: maybe some anti predator strategies aimed at orca were just
Speaker 2: also just also happened to, by coincidence, be better at
Speaker 2: evading human whalers.
Speaker 1: Yeah, it sounds likely because certainly one of the things
Speaker 1: about the industrial ages just had faster ships and they
Speaker 1: could keep up with whales, and they could get those
Speaker 1: whales that were further out. So great whales in the
Speaker 1: North Pacific were greatly reduced by this time, and those
Speaker 1: that remained were even harder to acquire. Jones also notes
Speaker 1: that by nineteen thirty six, the average size of grey
Speaker 1: whales captured was greatly decreased, and the reasoning here was
Speaker 1: quote the population was no longer seeing its members to adulthood,
Speaker 1: because again, these are creatures. They can live I think
Speaker 1: upwards of late like eighty years or so if I'm
Speaker 1: remembering correctly, and they're just they That's how impacted the
Speaker 1: population was now today. Carwoden notes that while grey whales
Speaker 1: in general have greatly rebounded and like, if you look
Speaker 1: them up online, you'll quickly see that they're listed as
Speaker 1: least concern as far as conservation status goes, which is
Speaker 1: great news. That's a heck of a comeback story. But
Speaker 1: they're still threatened by oil and gas developments in the
Speaker 1: Arctic and declining sea ice. Other threats include entanglement and
Speaker 1: fishing gear, occasional illegal harpooning, chemical pollution, noise pollution, ship collision,
Speaker 1: and the expansion of sea salt production in Baja California.
Speaker 1: In my own experience down there in Baja California, I
Speaker 1: mean the lagoon that we ventured out to in order
Speaker 1: to see the whales was surrounded pretty much only by
Speaker 1: salt industry projects, so I can understand what that would
Speaker 1: be a concern. Carwadine also notes that while the Eastern
Speaker 1: North Pacific group is doing great at the moment, there
Speaker 1: was you do see some fluctuations. So there was a
Speaker 1: six hundred and fifty one whale die off in nineteen
Speaker 1: ninety nine through twenty eleven, and that would have been
Speaker 1: like a twenty three percent population die off, though this
Speaker 1: doesn't necessarily reflect long term survivability. According to the NOAA,
Speaker 1: you can have big swings in population like that and
Speaker 1: it doesn't necessarily speak to how the species is doing
Speaker 1: long term. But that Western North Pacific population, like we
Speaker 1: said earlier, this one, according to Carbadene, is quote one
Speaker 1: of the most endangered whale populations in the world. So
Speaker 1: even though the species at whole is doing better, we're
Speaker 1: mostly looking at the Eastern North Pacific group as opposed
Speaker 1: to the West North Pacific group. Again, to whatever extent,
Speaker 1: that's a true separate population because we do see overlap
Speaker 1: in their breeding and behavior. So getting more back into
Speaker 1: just the migration patterns here that are pretty fascinating. We
Speaker 1: have the North Pacific gray whale to contend with here,
Speaker 1: and you have these two basic groups. The Eastern North
Speaker 1: Pacific grays migrate between those Baja California breeding lagoons and
Speaker 1: summer feeding grounds and the bearing chuck Chi and Beaufort seats,
Speaker 1: though this range is expanding as the ice opens up again.
Speaker 1: The Western North Pacific grays migrate between winter breeding grounds
Speaker 1: somewhere in the South China Sea to summer feeding grounds
Speaker 1: in the Sea of Okotsk and parts of Kamchatka, and
Speaker 1: there is some mixing of these groups in both the
Speaker 1: summer and winter. Now, the eastern North Pacific grays have
Speaker 1: the longer of the two migrations, spanning up to fifty
Speaker 1: degrees of latitude, according to Carwoodine, and the shortest return
Speaker 1: journey for these whales is about twelve thousand kilometers or
Speaker 1: about seven thousand, four hundred and fifty six miles. He
Speaker 1: adds that the longest documented migration of any mammal was
Speaker 1: a female gray whale with a twenty two thousand, five
Speaker 1: hundred and eleven kilometer round trip between sakal And Island,
Speaker 1: Russia and Baja California, Mexico. So that would have been
Speaker 1: again that we're talking about how there is overlap in
Speaker 1: the ranges of the eastern and the western. Now, note
Speaker 1: that there's also apparently a two hundred strong Pacific coast
Speaker 1: feeding group that doesn't migrate all the way up to
Speaker 1: the Arctic at all, but feeds off a coastal area
Speaker 1: stretching between northern California in southeast Alaska. And there's another
Speaker 1: group that feeds and Puget Sound. So all right, here
Speaker 1: are the stages of the migration, and in covering these stages,
Speaker 1: we're going to hit on some of the things we've
Speaker 1: discussed already, but try and keep it reasonably succinct here.
Speaker 1: But first we'll start with leaving the Arctic. Okay, they've
Speaker 1: been feeding. The whales has been feeding up north, and
Speaker 1: the signal to heads south seems to be a combination
Speaker 1: of the formation of sea ice and the decreasing day length.
Speaker 1: Apparently ninety percent leave the Bearing Sea through Inemac Pass
Speaker 1: on a sixty day journey to Baja California. Near term
Speaker 1: mothers leave first, then other adults, then immature females, and
Speaker 1: then immature males. The last are on their way south
Speaker 1: while the first group is already on their way back north. Again.
Speaker 2: Oh, that's interesting.
Speaker 1: The orca threat is far less during this part of
Speaker 1: the cycle, again referring back to the to the orcas.
Speaker 1: The orcas are are are intelligent and cunning in their
Speaker 1: hunting of these dangerous, these fearsome prey species. So at
Speaker 1: this point, the whales have been feeding all summer long,
Speaker 1: so they're they're they're fueled up, they're they're ready to fight,
Speaker 1: and their calves are are are even larger than they
Speaker 1: were previously, so everybody stronger, everyone's well fed. It's not
Speaker 1: to say that the orcas won't feed or won't attempt
Speaker 1: to acquire prey, but this is not the optimal time
Speaker 1: to do.
Speaker 2: It, and a reminder of what we talked about last time.
Speaker 2: This would be related to the fact that orcas are
Speaker 2: going to be mostly trying to prey on newborn whale
Speaker 2: calves for their return journey coming up the migratory corridor
Speaker 2: back to the feeding grounds, because a healthy adult gray
Speaker 2: whale is a pretty hard target, and orcas are observed
Speaker 2: to not never, but very rarely try to attack a
Speaker 2: healthy adult. Usually what they're trying to do is separate
Speaker 2: a young calf and prey on it.
Speaker 1: Yeah, exactly. So they make their way south and then
Speaker 1: it's lagoon time, and there are three main areas that
Speaker 1: they gather here. The exact amount of time spent in
Speaker 1: the lagoon's varies depending on sex and the presence of calves.
Speaker 1: Females with young calves just going to hang out far
Speaker 1: longer because you know, they need to bring get that
Speaker 1: young one up to wait up to strength before they
Speaker 1: head back out again, whereas like a male that's come
Speaker 1: down to breed. You know, obviously he doesn't have to
Speaker 1: stay as long's he can head back up as soon
Speaker 1: as he's ready. As we've discussed, these waters provide shelter
Speaker 1: against the orca, but they don't provide food. The adult
Speaker 1: whales don't feed while they're in the lagoon, and the
Speaker 1: whales that are born here while they drink their mother's milk,
Speaker 1: and of course that is you know, just going to
Speaker 1: sort of drain the mother is even more so.
Speaker 2: This makes it really important that they fatten up as
Speaker 2: much as possible before the journey south.
Speaker 1: Exactly. Yeah, like we said, they seem safe from the
Speaker 1: orca here because the orca are hesitant to enter into
Speaker 1: shallow waters where they won't be able to employ their
Speaker 1: full range of pack hunting techniques, and also where I
Speaker 1: don't know if we mentioned this either, but there are
Speaker 1: a lot of whales in these waters. Like when I
Speaker 1: was out there, you'd see just they were everywhere. There
Speaker 1: were just hundreds of them. In fact, I saw they
Speaker 1: had a tallied count even at the Whale center there
Speaker 1: and the figures I'm pulling this up on my phone.
Speaker 1: I took a picture of it. But the total count
Speaker 1: for mothers with babies was three hundred and twenty two.
Speaker 1: The lonely whale count was two eighty seven. So like
Speaker 1: this is just the count. It was like nine hundred
Speaker 1: and thirty one whales already during that breeding season. So
Speaker 1: another reason I guess to tread carefully. If you're an orca,
Speaker 1: you know you're going to go into this area where
Speaker 1: you can't use all of your tactics, and there are
Speaker 1: tons of whales that, as we mentioned, may work together
Speaker 1: against you if you present yourself as a threat. Right,
Speaker 1: But that doesn't mean they don't know about these lagoons.
Speaker 1: That don't mean they don't occasionally even venture in on
Speaker 1: a scouting mission. They're out there beyond the limits of
Speaker 1: the lagoons more or less waiting because again, as Carboning
Speaker 1: points out, the orca choose to strike quote when natural
Speaker 1: features tip the balance in their favor. All right, So
Speaker 1: but eventually it's time to head north again. These they
Speaker 1: haven't been feeding. Everyone needs to get back to those
Speaker 1: feeding grounds. So first, all the whales except mothers and
Speaker 1: cows if they tend to take the more direct route
Speaker 1: that has brought them there. So for instance, if there's
Speaker 1: a you know, they stick more or less to the coast,
Speaker 1: but if there's an area where there's like a bay
Speaker 1: or something, or a little inlet, they're more likely to
Speaker 1: just go straight across that inlet instead of hugging the
Speaker 1: coast through all the milks and crannies.
Speaker 2: Right a little more as the crow flies.
Speaker 1: Right, But when the mothers and calves leave, this is
Speaker 1: about one to two months later. The calves have grown
Speaker 1: stronger on milk, and it's they're far more prepared than
Speaker 1: they were to head out into these dangerous waters. But
Speaker 1: it ends up also being a longer trip for them
Speaker 1: because they are going to stick closer to the shore.
Speaker 1: They are going to travel around all the contours of
Speaker 1: the shore as much as possible, rather than crossing or
Speaker 1: cutting corners. And I think it's pretty obvious why.
Speaker 2: Right, Because, as we discussed last time, one of the
Speaker 2: main anti predator strategies of the gray whale trying to
Speaker 2: get away from an orca attack or orca harassment is
Speaker 2: to retreat into the shallows, where the orcas certainly can't
Speaker 2: attack effectively and often won't even try to follow right.
Speaker 1: So for this reason, they tend to stick within two
Speaker 1: hundred meters or about six hundred and fifty six feet
Speaker 1: of the shore, often moving through celt beds now. This
Speaker 1: is definitely the most dangerous part of the whole migration cycle,
Speaker 1: though in general the return trip, because the calves have
Speaker 1: had a month or two to grow and gain strength,
Speaker 1: but they are still at their most vulnerable during this leg.
Speaker 1: So you know, the mothers that are protecting them have
Speaker 1: not fed in months, and then increasingly as they move north,
Speaker 1: I mean, they're also going to grow a little bit
Speaker 1: weaker they've only had the milk to feed off of.
Speaker 1: And then again, the orca are going to strike when
Speaker 1: conditions are most optimal for them. And generally there are
Speaker 1: two major known attack spots along the journey attack hot spots,
Speaker 1: as the literature refers to them. One of them is
Speaker 1: Monterey Bay in California, and the other is Alaska's Unimak Pass.
Speaker 1: Is the most popular of the two, and this has
Speaker 1: to do with the fact that both the mothers and
Speaker 1: the calves are kind of an optimal weakness here. This
Speaker 1: is further north on the return trip, so like everything
Speaker 1: is tipping in favor of the orca at this point,
Speaker 1: and so a number are just going to be picked
Speaker 1: off during this period. That's just how it goes. That's
Speaker 1: the cycle of predation. But enough are going to reach
Speaker 1: those northern waters, and at that point this whole cycle
Speaker 1: begins again. They reach the northern waters, it's time to feed,
Speaker 1: to gain strength, to fatten up, and the whole cycle continues.
Speaker 1: And of course part of this whole cycle is the
Speaker 1: barnacles because the barnacle. Again, those calves are born without
Speaker 1: the barnacles, but those barnacles will grow. The life cycle
Speaker 1: of the barnacles is tied up with the life cycle
Speaker 1: and the travels of these whales.
Speaker 2: That's right. We are never without our barnacles, are we,
Speaker 2: whether metaphorical or literal. So grey whales, just to do
Speaker 2: a quick refresher on our previous discussions about whales and
Speaker 2: whale barnacles, gray whales and other species such as humpbacks
Speaker 2: and so forth, are regularly found carrying a large load
Speaker 2: of barnacles. And a barnacle is a filter feeding crustationan
Speaker 2: It's kind of like a tiny shrimp that is stationary
Speaker 2: for the adult portion of its life. So a barnacle
Speaker 2: will generally swim around as a larvae, as a youngling,
Speaker 2: and it will find a suitable substrate, then cement its
Speaker 2: head to that substrate and then build a hard shell
Speaker 2: out of calcium carbonate plates. And these shells can take
Speaker 2: many different forms. They can look like anything from a
Speaker 2: concrete pumpkin to a little volcano. And then they live
Speaker 2: by filter feeding. They wave these little legs called a
Speaker 2: cyri out in the water to catch bits of plankton
Speaker 2: and pull them in and eat them. Some species of
Speaker 2: barnacle specialize in living on the bodies of whales, and
Speaker 2: this is of course great for the barnacle because it
Speaker 2: provides a steady flow of water to feed from. Barnacles.
Speaker 2: Often when they're not on whale, many barnacle species try
Speaker 2: to like find a spot in the intertidal zone where
Speaker 2: the tides are going to be moving waters over them
Speaker 2: in and out all day, because they need moving water
Speaker 2: to help catch their food. To bring food to them.
Speaker 2: I think the way we put it was that they
Speaker 2: need high foot traffic areas. So latching onto a whale
Speaker 2: is a great adaptation. That's going to have water flowing
Speaker 2: over you all the time as the whale swims. But
Speaker 2: also it's very helpful in that it provides protection from
Speaker 2: predators and you can see some evidence of this in
Speaker 2: the size that whale barnacles grow to, and in the
Speaker 2: fact that they often have a shell or plate design
Speaker 2: that is less defensive looking, like they close less completely
Speaker 2: and often have more fleshy bits just kind of poking
Speaker 2: out all the time. So this relationship definitely helps the barnacles.
Speaker 2: But how does it affect the whales. That's not entirely clear.
Speaker 2: We talked about some arguments several different ways in the
Speaker 2: previous episode. It may hurt the whales by causing drag
Speaker 2: during swim This would of course reduce swimming speed and
Speaker 2: efficiency for the whale. It might possibly also help the
Speaker 2: whale in some cases by providing kind of armor plating
Speaker 2: for violent encounters with orcas or intraspecific aggression between say,
Speaker 2: male humpbacks during mating season, but that's not certain. That's
Speaker 2: a maybe. But whatever the effect on the whales, it
Speaker 2: is normal to find gray whales covered in hundreds of
Speaker 2: pounds of barnacles by adulthood, so they've got a bunch
Speaker 2: of barnacles on there. In fact, grey whales have a
Speaker 2: particular specialist type of barnacle that is unique to them
Speaker 2: called cryptoleapos RAKIANECTI. So that's the background. But I wanted
Speaker 2: to come back to barnacles because I was reading a
Speaker 2: really interesting article in Hakai magazine by an author named
Speaker 2: Mara Grunbaum. This was published in November twenty twenty one,
Speaker 2: and the article is called what Whale Barnacles Know. Very
Speaker 2: interesting article worth looking up and reading in full, but
Speaker 2: I just wanted to mention a few elements from it
Speaker 2: that caught my attention. So one thing I don't think
Speaker 2: I fully clocked when we talked about whale barnacles in
Speaker 2: the previous episode is how big some of them get.
Speaker 2: Was some species of whale barnacles grow very large compared
Speaker 2: to most barnacles you would find attached to stationary surfaces.
Speaker 2: The article here compares them at the upper end to
Speaker 2: several things. Compares them to the size of a coffee mug,
Speaker 2: a tennis ball, or a clementine orange.
Speaker 1: Rob.
Speaker 2: I don't know how big the barnacles on the gray
Speaker 2: whales you saw were, but some of these photos I've
Speaker 2: now seen with other objects for scale makes you realize, like, wow,
Speaker 2: those are some beasts.
Speaker 1: Yeah, I mean the ones I saw were pretty large.
Speaker 1: And then of course you would. You would sometimes see
Speaker 1: them clump together as well, so that kind of adds
Speaker 1: to the feeling. But individually, yeah, some of them are
Speaker 1: quite large.
Speaker 2: So there's one fact that is offhandly alluded to in
Speaker 2: this article that I hadn't come across before, and it
Speaker 2: made me want to do some digging because I found
Speaker 2: it fascinating. But there is a passage where Grunbaum writes, quote,
Speaker 2: these unbudging appendages speaking of whale barnacles, of course, which
Speaker 2: colonize a dozen odd different whale species, latch on so
Speaker 2: tightly that they are practically part of the whale's skin.
Speaker 2: As a result, they were carried into caves by Southern
Speaker 2: African people who foraged washed up whale meat one hundred
Speaker 2: and sixty four thousand years ago. So WHOA, that's an
Speaker 2: image prehistoric people foraging whale meat. I don't know why
Speaker 2: I wouldn't have imagined that happened before, but it totally
Speaker 2: makes sense. So I decided to look up the primary
Speaker 2: evidence for this. I believe the author here is citing
Speaker 2: some findings from a place called the Pinnacle Point Cave
Speaker 2: thirteen b in South Africa, in which fragments of whale
Speaker 2: barnacle were found, but this is not in fact the
Speaker 2: only case of whale barnacles being found away from the
Speaker 2: ocean in caves inhabited by prehistoric peoples, giving evidence that
Speaker 2: these people foraged whale meat. Another example I came across
Speaker 2: was a cave in Spain. This was written about in
Speaker 2: a paper by Esteban Alvarez Fernandez at All published in
Speaker 2: the Quaternary Journal in twenty fourteen. Papers called occurrence of
Speaker 2: whale barnacles in Nergia Cave Malaga, Southern Spain indirect evidence
Speaker 2: of whale consumption by humans in the Upper Magdalenian and
Speaker 2: the authors write, quote whale barnacles indicate that maritime oriented
Speaker 2: forager human groups found stranded whales on the coast and
Speaker 2: because of the size and weight of the large bones,
Speaker 2: transported only certain pieces such as skin, blubber and meat
Speaker 2: to the caves where they were consumed. And so we
Speaker 2: have this evidence of consumption of whale flesh soft parts
Speaker 2: of whale flesh, not the bones in these human caves,
Speaker 2: because the barnacles are in there. How else would the
Speaker 2: barnacles get into these human inhabited caves. They're stuck to
Speaker 2: whales all the time. So because many whale barnacles are
Speaker 2: adapted to a particular host species, you can also tell
Speaker 2: in these cases what type of whale meat the people
Speaker 2: were eating, and in this case it was two different
Speaker 2: species of barnacle that are found on the southern right whale.
Speaker 2: That's also interesting because these whales are only found much
Speaker 2: farther south today. But the author's right quote because of
Speaker 2: Antarctic sea ice expansion during the last glacial period, these
Speaker 2: whales could have migrated to the northern hemisphere and reached
Speaker 2: southern Spain.
Speaker 1: Oh wow, that's fascinating.
Speaker 2: So these are not grey whales, But because grey whales
Speaker 2: also have associated barnacle species, you could, by the same
Speaker 2: method potentially identify ancient ranges of gray whales by looking
Speaker 2: for evidence of their dedicated barnacles. And there's another way
Speaker 2: this article gets into that. You could look at the
Speaker 2: prehistory of whales that look at the ancient movements of
Speaker 2: whales by looking at barnacles. I'll get to that in
Speaker 2: a second, but first I wanted to mention a couple
Speaker 2: of other interesting facts. So one thing is this article
Speaker 2: just describes some of like the difficulties in the research
Speaker 2: on whale barnacles, like it's hard to acquire whale barnacles
Speaker 2: alive and study them, say, to study their reproduction in
Speaker 2: the lab, for obvious reasons and for less obvious ones.
Speaker 2: The obvious reasons would be like they are attached to
Speaker 2: living whales, and the less obvious reasons would be because
Speaker 2: these barnacles are not as they're not as hardy for
Speaker 2: taking them out of their natural environment because, for example,
Speaker 2: these whale barnacles typically can't seal themselves shut completely, so
Speaker 2: they can't fully close the door to keep the water
Speaker 2: inside when you remove them from their original context. So
Speaker 2: like you find out a whale washed up on a beach,
Speaker 2: the whale barnacles on it will typically die pretty quick,
Speaker 2: and so no when the article stresses how nobody really
Speaker 2: has figured out yet the right way to care for
Speaker 2: and preserve the lives of these animals once they are
Speaker 2: taken off of the whale they belong to. But there's
Speaker 2: another thing I wanted to emphasize grin Bond describes, which
Speaker 2: is the kind of the more body horror aspect of
Speaker 2: the boundary point between whale and barnacle, which is maybe
Speaker 2: kind of a gray area. It is like where one
Speaker 2: begins and the other ends. Grindam writes, quote, each of
Speaker 2: these barnacles has a shell structure specially evolved to anchor
Speaker 2: itself into its host's flesh. Many species have chambers within
Speaker 2: their wall plates into which prongs of whale skin grow upward,
Speaker 2: strengthening the barnacle's grip. And this further explains actually, like
Speaker 2: why it is hard to access living whale barnacles for research.
Speaker 2: It's not just a question of kind of like popping
Speaker 2: one of them off. It would generally require cutting into
Speaker 2: the whale's flesh to separate the barnacle from the whale.
Speaker 1: Oh yeah, yeah, I mean this, you know, comes back
Speaker 1: to like why did the gray whales have their their
Speaker 1: signature appearance, And a lot of it is part of
Speaker 1: it the barnacles, but also like these gray sort of
Speaker 1: sploshes on their body scars from various things, including scars
Speaker 1: from where the barnacles were previously attached.
Speaker 2: Yeah, yeah, scars, because they're like, you know, they really
Speaker 2: like grab a hole they get in there. Another thing
Speaker 2: I've read about is that apparently the areas underneath the
Speaker 2: barnacles tend to become depigmented on whale skin, so you
Speaker 2: can often see them by that there there'll be like
Speaker 2: a different shade than the surrounding skin.
Speaker 1: Now we're going about to get into a really interesting
Speaker 1: area here, because you know, the thing about living your
Speaker 1: full life on a migratory large mammal like this is
Speaker 1: that your your life cycle is intrinsically tied to the
Speaker 1: movements in life cycle all of your host species.
Speaker 2: That's right, and partially for this reason, there's so much
Speaker 2: we don't know about the whale barn life cycle. There's
Speaker 2: things we don't know about their cycles and their reproduction.
Speaker 2: They're just hard to study. So they seem to mate
Speaker 2: with other barnacles nearby on the same whale, but they
Speaker 2: wait until the whales go to their coastal breeding and
Speaker 2: calving grounds to release their larvae. And these larvae are
Speaker 2: probably guided by an attraction to a chemical signal that
Speaker 2: helps them find the whale skin. This could be a
Speaker 2: chemical emitted by other barnacles already present. So maybe there's
Speaker 2: kind of a you know, I don't think qorm sensing
Speaker 2: is the right word. That's from different but you know,
Speaker 2: they sense a congregation of their kind, or it could
Speaker 2: be a biosignature from the skin of the whale itself.
Speaker 2: Maybe they're attracted to some kind of signature mammalian molecule.
Speaker 2: They also have to do some crawling around on the
Speaker 2: whale as larvae before they cement themselves down, because you
Speaker 2: don't just go anywhere on the whale. There are favored
Speaker 2: regions of the whale's body, often the forehead, the tail,
Speaker 2: and the the forward facing edges of the flippers, and
Speaker 2: I think this is because it increases their access to
Speaker 2: flowing water and the plankton in it. But finally, there's
Speaker 2: a really big interesting thread in this article that's about
Speaker 2: studying the chemical composition of whale barnacle shells to determine
Speaker 2: where whales travel. So barnacles are, you know, their shell builders.
Speaker 2: They are constantly building up new layers of their calcium
Speaker 2: carbonate plates, and at some point researchers figured out that
Speaker 2: you could look at the layers of these plates kind
Speaker 2: of like tree rings. But by analyzing the ratio of
Speaker 2: oxygen isotopes in each layer, you couldn't just tell, you know,
Speaker 2: it's not just counting the tree rings. You could actually
Speaker 2: say a lot about the properties of the water in
Speaker 2: which each layer was formed. So what was the temperature
Speaker 2: of the water, what was the salinity, et cetera. And
Speaker 2: actually you could then compare that information to things we
Speaker 2: know about different regions of the ocean at different times,
Speaker 2: and this would allow you, by proxy to roughly track
Speaker 2: the migration history of the whale on which a barnacle
Speaker 2: lived by peeling back and analyzing the mini layers of
Speaker 2: its plates. And researchers initially studied this on the shells
Speaker 2: of living or recently living barnacles, but it turns out
Speaker 2: you could even do this with fossilized remains of whale barnacles,
Speaker 2: and by this method you can track the movements not
Speaker 2: only of living whales or recently living whales, but whales
Speaker 2: that lived hundreds of thousands of years ago, and that information,
Speaker 2: in turn can help shed light on unsolved problems in
Speaker 2: whale evolutions, such as when and why did billine whales
Speaker 2: start migrating. Groombamb writes quote One hypothesis suggests that it
Speaker 2: happened around three million years ago, when massive ice sheets
Speaker 2: started spreading across much of the northern hemisphere. The colder
Speaker 2: temperatures would have frozen whales out of some of their
Speaker 2: habitats and put more constraints on where plankton could flourish
Speaker 2: in Earth's oceans, and the patterns that came to exist
Speaker 2: in the locations of these, say food and shelter resources,
Speaker 2: would therefore lead to the establishment of migration patterns over time.
Speaker 2: We don't know exactly how it happened, but that's one idea.
Speaker 2: And so it seems like we can now maybe use
Speaker 2: fossilized whale barnacles to get some insight into what those
Speaker 2: ancient patterns of migration were when they changed, and what
Speaker 2: those changes might coincide with, say in the climate sphere.
Speaker 2: And this of course can help shed light on things
Speaker 2: today as well. Doesn't just tell us about the past,
Speaker 2: because understanding when and why ancient whales started changing their
Speaker 2: migratory patterns, for example, in relationship to ocean temperatures and
Speaker 2: sea level and so forth, that could help us understand
Speaker 2: what's likely to happen in the near future with oceans
Speaker 2: being affected by our rapidly heating planet. So anyway, it
Speaker 2: was just a few notes from there, but that article
Speaker 2: What Whale Barnacles Know very interesting worth a read.
Speaker 1: Yeah, yeah, I mean it's interesting to think about. It's
Speaker 1: easy to dismiss the barnacles. It's just this hanger on,
Speaker 1: just this exo parasite of the whale, but there's so
Speaker 1: much information tied up in the barnacle about the host species. Well,
Speaker 1: this has this has been a really fun journey. I've
Speaker 1: really enjoyed getting to dive in to researching the gray
Speaker 1: whale after getting to have this experience with them. I
Speaker 1: guess some people would probably do this in reverse order
Speaker 1: to do their research and then have the experience, but
Speaker 1: for whatever reason, I end up doing it the other
Speaker 1: way around most of the time. But I enjoyed it.
Speaker 1: I kind of that's one way to sort of draw
Speaker 1: out these experiences.
Speaker 2: Oh, I don't think it's a bad way at all,
Speaker 2: experience and then reflect. Yeah.
Speaker 1: Yeah. By the way, I've cited several authors and sources
Speaker 1: that were helpful in the research for these episodes, but
Speaker 1: I'd also like to throw in some hefty thanks to
Speaker 1: the local guides at the Ojo de Labre Lagoon, some
Speaker 1: of which have been doing this sort of guide work
Speaker 1: every year for something like thirty five years, as well
Speaker 1: as the international tour guides that I had there, Keith
Speaker 1: Hassan and Donna in particular. Everyone was delightful and full
Speaker 1: of wonderful facts and observations about the whales. And I
Speaker 1: also really enjoyed the company of the folks that my
Speaker 1: family toured with. In case any of you out there
Speaker 1: having to be listening, the great thing about a trip
Speaker 1: like this is that no one is that is there
Speaker 1: is just kind of sort of into wales like everyone.
Speaker 1: At least in my experience, everyone was really excited, really
Speaker 1: into them, and really compassionate for them. So yeah, just
Speaker 1: a shout out if should any of you be listening.
Speaker 1: All right, We're going to go ahead and close the
Speaker 1: book on this one, but we'll be back with more
Speaker 1: episodes next week. Just a reminder that Stuff to Blow
Speaker 1: Your Mind is primarily a science podcast, with core episodes
Speaker 1: publishing on Tuesdays and Thursdays, but on Mondays we do
Speaker 1: listener mail. On Wednesday's a short form artifact or monsterfect episode,
Speaker 1: and on Fridays Weird House Cinema. That's our time to
Speaker 1: set aside most serious concerns and just talk about a
Speaker 1: strange film.
Speaker 2: Huge thanks to our audio producer JJ Posway. If you
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