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Tuesday, 31 May 2011

Giant Beavers

Scale Drawings and Reconstructions for Castoroides.

One of the interesting "Unclassified" reports of "Ogopogo" in British Columbia concerns a report of a supposed carcass thought to be the creature. In 1914 at Lake Okanagon, a group of Nicola Valley and Westbank Indians discovered the decomposing body of an unidentified creature across from Rattlesnake Island. Five to six feet long and estimated to weigh 400 pounds, it was blue-grey in colour. It had a tail and flippers, and an amateur naturalist in the area felt that it was a manatee. No one knew how such a creature could have gotten into the lake, and Peter Costello has hypothesized in In Search of Lake Monsters that the carcass was "actually an Ogopogo, as the details of this mammal with flippers and a broad tail and dark color are all that we would expect. But the carcass was mangled so much that the long neck was already gone."
That might have made sense but for the fact that Ogopogo is NOT often reported with a long neck. On the other hand it matches well enough with a series of reported Water Monsters that appear to be actually Giant Beavers.

[Scale Comparison by Dale D.]

Going through the archives of the Frontiers of Zoology on Yahoo, we can pull out several older messages on the suibject of Giant Beavers, starting in 2006:
Message # 314 in this group's archives includes this information:
Oddly enough, Bernard Heuvelmans discarded the idea of Giant beavers out of hand when he was putting together his checklist of Unknown animals (Cryptid Categories) in 1989. That was peculiar because Giant beavers are one of the more "Ordinary" types of Cryptids categories which has been advanced and one which corresponds to a species known to have lived as recently as the end of the Ice Age.
In his book Strange Creatures from Time and Space (I have the
original printing,It has been subsequently reprinted under a different title),
John Keel includes a couple of reports from upstate New York that
I thought when the book came out sounded like giant beavers. One is
a Water monster report under the heading "Bilious bogeymen" on page
265 and mentioned as being in the Black River, in the Adirondacks. it
was estimated as 15 feet long with handlike forelimbs and dark brown
in color, with round black eyes the size of silver dollars. This would be only SLIGHTLY exaggerated. Another one was oddly placed under a series of "ABSM' reports on page 113 and was reported to be a "ground sloth" from Sherman New York,
from a swamp. It was said to be 12 to 18 feet tall with a tail 6 to 8 feet long, reported by a 15-year-old. Using the "Halve all measurements" method, it would be 6 to 9 feet tall and with a tail 3 or 4 feet long, making a very respectabnle Giant beaver report out of something outlandish.
Costello noted a reported corpse for the Bear Lake monster, but also a "Manatee" carcase in Lake Okanagon. He thight these were long-necked seals, but the manatee-like tail is very like a beaver and I would consider these both to be recent-Castoroides carcases.
Oh, and if Loren Coleman should want to mention this in
Cryptomundo, he has free use of this information. So do all the rest of you
guys. Loren Coleman says that the Bear Lake Monster was a remnant giant beaver, Castoroides. I think that it is an exellent suggestion. ...

[Reply] --- Craig Heinselman wrote:
Bear Lake Monster? Yes, says historian
[These links appear to be removed]

And in Message #315 from group's archives:
Lake Monsters in the Indiana-Ohio-Kentucky area
The most recognizable local mammalian Water monster around these
parts is a dark-furred creature the size of a hog or a cow with big
round black eyes and the ability to decamp across-country when its
ponds are drained. It may make a whistling or screeching noise. Its
distribution is usually connected to the Ohio river area (one
famous[but gray-colored] Indiana Water monster is from Lynn, on a
tributary leading to the Ohio River, but other reports also come from
further north in Indiana--and VERY rarely!) Several reports mention only its "Pig
snout" area around the nostrils breaking the water to breathe. it is sometimes mentioned as having heavy whiskers on its nose. It can travel in family groups when seen swimming.

[With this later additional information]
Ivan T. Sanderson records a track attributed to "Old Three-Toes" on the Monogahela River and in this case I think it more likely to be an incomplete track of a web-footed Giant Otter. "Flippere-like" tracks are elsewhere reported in Kentucky and Southern Indiana.Eberhart lists the Water Monster in the Monongahela River (West Virginia) as Ogua, Agou or Agua, possibly an Algonquin-family languagge word which is possible although it sounds mighty close to the Spanish word for Water.The creature is supposed to weigh 500 pounds, be 20 feet long with a hinder fin sticking up six to eight feet, a snakelike or turtlelike head and a long flat tail.It is amphibious and comes out on shore at night, allegedly to ambush deer. It is covered with reddish brown fur.In the daytime it is supposed to live in caves it digs in the bank from below the water level. A prominernt sighting in 1983 is mentioned by Eberhart. This is very likely a pen-picture of the same kind of Giant Beaver and halving the dimensions makes it ten feet long with a hind limb three to four feet long (Tail presumably about the same):: the rounded head would be more turtlelike than snakelike and the "Long Fangs" would be the animal's incisors. A very similar traditional Water-Monster is reported on the Missouri River especially in the Dakotas, as mentioned in another of Eberhart's entries.
The Giant-Beacver like reports around Lake Okanagon and further to the north are "Water Bears" or Ta-Zam-Na, and basically described as a beaver the size of a bear. Rumors of similar nature came out of the Rocky Mountains of Montana and the Yellowstone region, And Loren Coleman mentions a more recent report from Lake Mead (which is an artificial reservoir) in his Field Guide.

Indications of Giant Otter and Giant Beaver Reports in North America, Map by Dale D. The Beaver reports are the grey squares and the black area is for the Master-Otters or Water-Panthers, generalised. Both types of reports have been in drastic decline since the Colonial period.

Museum Display for Castoroides.

Castoroides ohioensis was a species of giant beaver, huge members of the family Castoridae (Rodentia), endemic to North America during the Pleistocene epoch (1.8 mya—11,000 years ago).[2]


Castoroides ohioensis had a length of up to 2.5 m (8.2 ft)[1] [Not counting the tail] and an estimated weight of 60-100 kg (130-220 lbs) estimates have gone as high as 220 kg (485 lbs).[3] It lived in North America during the Pleistocene epoch and went extinct at the end of the last Ice Age, 12,000 years ago.[4] The extinction of the giant beaver may have been due to ecological restructuring at the end of the Pleistocene.[5] The arrival of humans in the Americas could have been a factor, but there is no evidence that humans hunted the giant beaver.[4] It was one of the abundant Pleistocene megafauna—a wide variety of very large mammals that lived during the Pleistocene.

Fossils of the giant beaver are concentrated around the Midwestern United States in states near the Great Lakes, particularly Illinois and Indiana, but specimens are recorded from Alaska and Canada to Florida.[1] Specimens from Florida have been placed in a subspecies, Castoroides ohioensis dilophidus, based on differences in premolar and molar features.[6]

One of the important anatomical differences between the giant beaver and modern beaver species, besides size, is the structure of their teeth. Modern beavers have chisel-like incisor teeth for gnawing on wood. The teeth of the giant beaver are bigger and broader, and grew to about 15 centimeters (6 inches) long.[4] In addition, the tail of the giant beaver may have been longer but narrower, and its hind legs shorter.[1] Its great bulk might have restricted its movement on land (although large squat-legged hippopotamuses can move on land with little difficulty).

The first Giant Beaver fossils were discovered in 1837 in a peat bog in Ohio,[4] hence its species epithet ohioensis. Nothing is known on whether or not the Giant Beaver built lodges like modern beavers. In Ohio, there have been claims of a possible Giant Beaver lodge four feet high and eight feet in diameter, formed from small saplings.[4] The recent discovery of clear evidence for lodge building in the related genus Dipoides indicates that the Giant Beaver probably also built lodges.[7]

Both the native Mi'kmaq people of Canada and the native Pocumtuck people of the Connecticut River Valley of Massachusetts have related significant myths about giant beavers; see Glooscap and Pocumtuck Range for details. The Cree people also have myths about giant beavers.
[Emphasis added]

See also
Castoroides leiseyorum – a species of Giant Beaver restricted to current-day Florida
Castoroides – the genus of Giant Beavers
1 ^ a b c d e Kurtén, B. and E. Anderson (1980). Pleistocene Mammals of North America. Columbia University Press. pp. 236–237. ISBN 0231037333.
2 ^ PaleoBiology Database: Castoroides ohioensis, basic info
3 ^ Reynolds, P.S. (2002). "How big is a giant? The importance of methods in estimating body size of extinct mammals". Journal of Mammalogy 83 (2): 321–332. doi:10.1644/1545-1542(2002)083<0321:HBIAGT>2.0.CO;2.
4 ^ a b c d e Harrington, C.R. (1996). "Yukon Beringia Interpretive Center - Giant Beaver". Archived from the original on 2007-09-14. Retrieved 2007-09-17.
5 ^ Parmalee, P.W. and R.W. Graham (2002). "Additional records of the Giant Beaver, Castoroides, from the mid-South: Alabama, Tennessee, and South Carolina". Smithsonian Contributions to Paleobiology 93: 65–71.
6 ^ Martin, R.A. (1969). "Taxonomy of the giant Pleistocene beaver Castoroides from Florida". Journal of Paleontology 43 (4): 1033–1041.
7 ^ Rybczynski, N. (2007). "Castorid phylogenetics: implications for the evolution of swimming and tree-exploitation in beavers". Journal of Mammalian Evolution 14 (1): 1–35. doi:10.1007/s10914-006-9017-3.


  1. Comment just submitted at the Frontiers of Zoology Yahoo Group:

    Dave Francazio asks: For the giant beaver, wouldnt the primary characteristic described be the tail?
    And although a beaver has a similarly shaped tail to a manatee, the texture and appearance are totally dissimilar.

    Dale Drinnon replies: You would think so, but as far as the scientific end of things goes, the shape of the tail in life is in dispute because the fleshy parts do not preserve as fossils. As far as the reports go, descriptions are ambiguous. Some reports say "a flat tail" but do not specify proportions. As far as the Okanagon carcass goes, we have no really minute descriptions and some amateur naturalist looked in the dictionary and the closest approximation they could find was to the illustration of a manatee. That much was obviously not a very expert opinion and not based on a very careful comparison. So looking for an intelligent observation as to the texture of the tail would seem not to have occured to the person who said it resembled a manatee (and that statement is the one that made it into all of the books even though it sounds a fairly flimsy identification)

    Lake Okanagon IS in an area where the legendary "Water bears" are reported.

    Best Wishes, Dale D.

  2. Dave and Dale, Round 2:

    Dave F. Said: Hmm, well I would expect an amateur naturalist to describe something as a beaver tail before calling it a manatee tail, especially if it was indeed more similar to a beaver tail.
    Flesh can sometimes be preserved in fossil, I was at the American Museum of Natural History and they had a edmontosaurus where much of the soft tissue was preserved :

    There are also skin impressions where there will be a fossil that shows the texture of the skin.

    I don't know if such fossils exist for the giant beaver, but it would stand to reason it would have a textured tail like the beavers of today.

    It just seems really odd to me that in the sightings of a giant beaver, people wouldnt be like "look a giant beaver!" and describe it as such.

    Dale D. Replied: unfortunately the occurnce was in the WWI era and we only have retellings of the event, not directly in any kind of report by any amateur naturalist. But I'll check it over again. I think you're just expecting more than the person had the ability to offer.

    You also caught me going out the door:I'll be away a few hours to get to some appointments.
    Best Wishes, Dale D.

    Dale D adds, after checking:
    I have looked up the information in Mary Moon's, Tim Dinsdale's, Ivan Sanderson's and Peter Costello's books in the sections that mention the carcass and all are agreed: the report is a FOAF report and only intermediary sources are named. The body was not recognisable beyond the fact that it had large tusks in its mouth, was covered in fur, had a round head and a flat tail, and it had clawed flippers. That seems to have been the published account which came to the hands of a reliable naturalist (Frank Buckland, who said the description came from a band of indians) and who told the FOAF report, giving the date of 1916 Roughly a decade later, some local Ogopogo enthusiasts started up a theory that Ogopogo was a manatee, citing other people's reports which sounded reminiscent of a manatee. At this point, one of the fellowws (seemingly anonymously) identified the 1916 carcass as a manatee (which contradicts the report in several ways, including thwe positive assertion that it was covered with fur that was coming out at the time of discovery).

    The description better fits a giant beaver decayed out of all recognisability. and the report mentions it was disarticulated and smelled strongly of fish. And once again, although the tail was mentioned as "Flat" we do not know if it was flattened vertically or horizontally, nor yey how short or long it was in proportion tp a beaver's, a muskrat's or a manatee's tail.

    Parts of the monster's body were said to have been collected and kept locally but were subsequently lost.

    And I'm sorry, but that all sounds so very suspicious. The chain of tellers of the story up to Buckland all sounds pretty exactly like a legend rather than a verifiable report: but the legendary description could still be valuable.

    Best Wishes, Dale D.

  3. There are a couple of problems with the dates in the foregoing material: My original message had a date of 1989 given for Heuvelmans' checklist as given in CRYPTOZOOLOGY magazine. Actually it was 1986. More importantly, the discovery of the carcass seems to have been 1914 (vague date) but the date at which the report was taken down was in 1916, approximately two years later. That is, if the accounting was accurate and it might have been. The description of the carcass could also have been accurate and a valuable piece of evidence. But the source of the story was an unnamed Native who told his fellows the story at one point and then (indefinite interval later) it came to the attention of Buckland's friend (we know his name, but it really isn't important) and Buckland wrote it down. In 1916. And the Manatee theory was being promoted in 1925-1926, this information specifically from Mary Moon's book Ogopogo.

  4. Oh, and about your three strategies, I am on board and similar. I comment to build relationship. Often, if I reply I will even remove ComLuv link so it doesn’t look I am there for links. I don’t look at PR anymore though.And I also try to read blogs that look like they will grow.
    volunteer central america

  5. OK.

    I have three strategies? It must have been a while since we discussed them because I do not get your reference to three strategies right off.

    Best Wishes, Dale D.

  6. As for no evidence of man ever hunting giant beaver I have actually heard that in Wausaukee, WI the skeleton of a giant man was discovered in a cave or on an island (can't remember which) and with him was the skeleton of a 9 foot beaver. Apparently there is a museum there or near there with these skeletons.

  7. Hi,
    My husband and I were visiting British Columbia from Australia and we were not really familiar with how big a beaver is supposed to be. We were flying in a helicopter over swampy land between Fort Nelson and Rainbow Lake when we saw an enormous beaver swimming in a river/creek. We got down low and hovered over it for quite a few minutes and were both amazed at how it just swam and dived in the water. It would easily have been the sie of a man, which we thought was normal as this was the first beaver we had seen. We were then talking to my husband's co-workers and they told us that beavers are much smaller, but both of us, without conferring, estimated this creature as being about 6 foot long. We have since seen stuffed beavers and they are nowhere near the size of the one we saw from the chopper, but seem to be the same shape. Just thought I'd mention this as we had just given up on anyone ever believing us, when we mentioned in to a store clerk here in Australia and they then saw a documentary the same night about the very same thing. What a coincidence. So they told us to look up ogopogo on the net, and we found your site. So, we're believers cos we saw the giant beaver with our own eyes and didn't even realize it was special.


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