Friday, 3 April 2015

Lake Monsters - What They Aren't

     They see them here, they see them there; they are - lake monsters. Now, far be it for me to reject or endorse every lake monster report, or to suggest that all of them, in every lake, belong to the same species. However, it might be an idea to consider some of the proposed explanations. For this, we could start with two propositions:
  1. It is far more likely they belong to a known group supposedly extinct than something which nobody has every heard of.
  2. They are part of the larger "sea serpent" phenomenon. The rule of parsimony would suggest that it is more likely that some unknown animals from the high seas have managed to get into freshwater lakes than that the sea serpents and lake monsters are two completely different phenomena. However, their presence in an enclosed lake raises issues not present in the open sea, as we shall see.
Plesiosaurs
     As we all know, this is the most all-time popular interpretation. The popular image of a plesiosaur matches the popular image of the Loch Ness monster, which has been largely generated by the famous Surgeon's Photo. It's a pity, because there are serious doubts about the authenticity of this photo, even if we discount the mini-submarine story, which has a lot of problems of its own. If you take a census of lake monster sightings, you will discover that long necks protruding from the surface like a periscope make up a very small proportion of them - but they do exist. What cannot be denied is that they make up a large proportion of "sea serpent" reports. And to make things more interesting, some of them have large eyes, and some extremely small, if not invisible eyes. However, identifying them as plesiosaurs raised a number of problems.
     First of all, the major consensus is that plesiosaurs could not stick their necks above the surface in the manner in which they are popularly portrayed. Their vertebral spines would have prevented this. All right, it is possible that they have evolved the skill in the 66 million years since they supposedly became extinct, but we're drawing a long bow.
     More importantly, they were reptiles, and so, presumably, "cold blooded". Yes, it is generally accepted now that a lot of the dinosaurs were at least partly "warm blooded", so it is possible that plesiosaurs followed suite. The problem is, there wouldn't be any need for them to be so. Indeed, it would have been a hindrance. In the tropics during parts of the Cretaceous, the sea temperature was like a hot tub - 33º to 42º C. That's blood heat, or higher. A marine reptile would operate at optimal body temperature by simply being in the water. On the other hand, a human being would be most uncomfortable in such water, because he would be unable to lose the heat his own body generated. Admittedly, it wasn't always as hot during the whole of the Cretaceous, or the whole of the world. Just the same, when the asteroid ended the Cretaceous - and allegedly, the plesiosaurs - the sea was pretty hot. However, from the data provided by Dr Heuvelmans, long-necked sea serpents have been reported in quite high latitudes, where sea temperatures are rather chilly. And nobody would claim that Loch Ness is warm.
     Both these factors should rule out plesiosaurs as the origin of sea serpent sightings. But there is one crucial factor which should rule them out completely as lake monster candidates.
     They have to breathe. And large aquatic animals which rise to the surface to breathe at regular intervals tend to get noticed frequently. But how frequently are lake monsters seen? Tim Dinsdale calculated that he spent a thousand hours watching Loch Ness between his first sighting and his second. I suppose, of course, it is theoretically possible for the animal to just poke its nostrils above the surface, by why would any long necked animal do that? It would serve no practical purpose. Dr. Roy Mackal pointed out that the sonar results are consistent with a creature which moves up and down in the middle depths, but only occasionally rises to the surface. (And incidentally, perhaps the debunkers would like to provide an explanation for the sonar results.)

Archaeocetes
     Archaeocetes were the most primitive group of whales, and the operative family for this discussion is the Basilosauridae, which allegedly went extinct about 35 million years ago, for they were elongated and serpentine in appearance. Now, there are innumerable reports of elongated sea serpents swimming with vertical undulations, which Zoology 101 will teach you is a feature of mammals, and only of mammals. Dr Mackal suggested them as a possible identification of what he calls "naitakas", the monsters of the western Canadian lakes. (Naitaka was the Indian name for the monster of Lake Okanagan, which the whites call Ogopogo.) In fact, one Ogopogo witness even cited a whale-like horizontal tail fluke.
     It all makes perfect sense - except that not matter how long a whale can hold its breath, it has to come up breathe and spout at very frequent intervals. Although a sign at Lake Okanagan declares that it is the home of Ogopogo, you know you would have to be incredibly lucky to see it. And let's be realistic: how long would it take for even a single whale to exist in even a large lake before its presence became of regular occurrence for every boat-user on the waters, it acquired a pet name, its movements were tracked in the local press, and tourists were setting out with a reasonable expectation of sighting it?

Long-Necked Seal
     This, of course, was the theory of Antoon Oudemans and, if you don't mind my saying so, one of the silliest. To be fair, he proposed it for sea serpents, not lake monsters, but even then there are problems. For a start, seals have to come to shore to bear and raise their young. Secondly, seals are mammals, and mammals possess only seven neck vertebrae. Even a giraffe has only seven. Yes, there are a few exceptions. Manatees have only six, two-toed sloths five, and three-toed sloths nine. So it is possible for mutations to have a minor effect but, by and large, mammals appear to lack the genetic ability to change the number of their neck vertebrae. It is pushing the odds a bit to propose that one branch of the seal lineage has not only grown huge, found a way to bear its young at sea, and multiplied its neck vertebrae such that the neck is as flexible as it appears, and as flexible as is needed to chase fish underwater. A stiff, giraffe-like neck would be counterproductive under the circumstances.
     And, of course, in a lake seals still have to breathe.

So, what are they?
     I don't know. This essay is only intended to dispel misconceptions, not explain the whole topic. I think that basilosaurids are still the best candidates for many sea serpent sightings. I have no idea what long necked sea serpents might be. But I am convinced that lake monsters, to the extent that they actually exist, do not belong to any order of animals which has lungs.
     In an earlier post, I suggested that the Lake Labynkyr monster (which is known only from a single sonar reading) is probably a large sturgeon. It appears to me, having due regard to possible misperceptions, that some of the "lake monsters" in Quebec, such as Memphré in Lake Memphrémagog and Ponik in Lake Pohénégamook, or Mocking Lake, are also consistent with large sturgeons. Nevertheless, I would hesitate to apply that hypothesis to every single lake monster. And, of course, it would not apply to anything south of the Equator.
     So there the mystery rests.

12 comments:

  1. A sea rather than lake monster: http://bizarrezoology.blogspot.com/2013/04/a-submarine-pilot-plesiosaur-sighting.html
    How to explain this in your context of possibilities? Indeed a mystery.

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  2. a very enjoyable read ... I'll be simplistic and just refer to them all as 'aquatic creatures' , at which point plenty of known animals fit the bill without having to introduce something unknown: sturgeon (as you mention), oarfish, a single-file group of otters or beavers or large turtles ... I'm sure you're familiar with all these explanation. In the open seas, perhaps still something unknown - but in retrospect Nessie just seems so unlikely as to be, simply, impossible. My opinion on that has been greatly reinforced by the wonderful Internet - until recently I didn't really distinguish between British journalism and American (we look alike, we talk somewhat alike), but their tendencies to over-dramatize things (especially UK things) proved to be quite a surprise. I think the UK always wanted 'their' own monster, making the 'great white hunter' have to travel to Africa or South America must have been discouraging (ie Piltdown man as a similar example). With the Dinsdale film shown to be a boat, the Rines photos heavily 'enhanced (30 years before the term 'photo-shopped' became a commonly used verb), and all photos from the 30's quite suspect, there really is nothing to bank on ... in my opinion.

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  3. Great questions Malcolm.
    http://aquaticandaerialanomolyassociation.blogspot.com/2014/04/the-american-aquatic-and-aerial-anomaly.html

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  4. I certainly agree that they are more likely to be supposedly extinct than new creatures and that they are temporary visitors from the sea. Gould suggested they came in from the sea but the big trouble for this idea is Bauer's confused and muddled version of this which is the straw man. I accept the careful and logical debunking of the surgeon's photo. At the time surgeon's were incredibly highly esteemed and it is likely he had sufficient contempt for folk beliefs to have done this. I do not know why you think the mini submarine is ludicrous. The worst part of that was the material which was not yet available at the time.This could be just a mistake of memory. Ectothermy is not an obstacle for leatherbacks or for plesiosaurs off the British Isles palmly shores. Plesiosaurs would not be ruled out as temporary visitors in warm months by their need to breath. You are falling into the trap of the idea that they reside permanently there. As for poking the head up more than just nostrils, predators are often very stealthy and elusive by habit.
    Archaeocetes may have been able to move through shallow water or even over bits of land
    like sand bars considering their ability to vertically undulate.

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  5. Could there be a variety of archaeocetes or basilosaurus that propels itself by multiple vertical undulations?

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    Replies
    1. Yes. I suspect that explains many sea monsters, but not lake monsters.

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  6. Such a method of propulsion would be consistent with the reports of great speed and elusiveness.

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  7. Then the "humps" are actually vertical undulations, as I have been supposing for years. Sometimes people have reported seeing under them.

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  8. If the can multiple vertical undulate then can they move on land?

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    Replies
    1. The impression I get is that their size is the same order of magnitude as that of whales, which means that their weight on land would be too much for their lungs to function - as is the case with whales. However, they would be better suited for moving in shallow water. Heuvelmans suggested that that is the reason why they do not get stranded as whales do.

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  9. Then if a basilosaur-like archaeocete exists that propels itself by multiple vertical undulations, if it does not have a blow hole on its back, could swim rapidly up rivers into lakes only needing to put its snout above water to breath. It could occasionally follow fish runs and return to the ocean without being noticed very easily.

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  10. Re: "I suppose, of course, it is theoretically possible for the animal to just poke its nostrils above the surface, but why would any long necked animal do that? It would serve no practical purpose."

    Plesiosaurs may not have been very fast swimmers and so may have practiced stealth tactics. They may have something to fear from other predators and from the sounds and sights of ships.

    Could plesiosaurs be entering temperate zone lakes in warm summer to reproduce/lay eggs at night? This would also be only brief and occasional visits.

    The idea is that the correct solution is that basilosaurs and plesiosaurs visit lakes and rivers only occasionally and only briefly.

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The Possum Book

I am pleased to provide a link to a website of a friend of mine, Robyn Tracey, who has written a fascinating story about her dealings with brush-tailed possums in the outer suburbs of Sydney. You can download the book for free, or read it on the site. Go to: The Possum Book.

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