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