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The amazing Hook Island sea monster photos, revisited

Long-time readers of Tet Zoo might remember Sea Monster Week: a series of articles I ran at Tet Zoo ver 2 back in 2008. 2008? That’s, like, years ago.

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Long-time readers of Tet Zoo might remember Sea Monster Week: a series of articles I ran at Tet Zoo ver 2 back in 2008. 2008? That’s, like, years ago. A recent discussion with ZSL’s Sam Turvey got me thinking about the Hook Island sea monster – an alleged sea monster photographed during the 1960s and frequently featured in books on monsters and mysteries. And I have sea monsters on the mind a lot anyway, due to the recent release of the Kindle version of Cryptozoologicon Vol I and the impending release (December 6th) of the hard-copy version (we’re holding a launch event in London: details here). Inspired, I’ve decided to republish my article on the Hook Island case, with updates…

The best known of the Hook Island sea monster photos is familiar to many (the two or three others are less familiar: read on). As shown above, it features a gigantic, tadpole-like monster, supposedly encountered in Stonehaven Bay, Hook Island, Queensland, by Robert Le Serrec and his family and a friend during the December of 1964. Judging from comments I’ve seen online, people nowadays tend to assume that it’s a photoshop job. In fact, it’s a classic, much-reproduced image, widely discussed in the cryptozoological literature.

Let’s note to begin with that – if the object depicted here really is a large, unknown marine animal – then it perhaps shouldn’t be featured on a website called Tetrapod Zoology, since the most popular proposed identification of the creature is that it’s some sort of weird giant fish. We’ll come to the subject of identification in a minute. The story starts in March 1965 when Breton photographer Robert Le Serrec claimed, in Australia's Everyone magazine, that he had obtained excellent, genuine photos of a real sea serpent: a creature discovered by chance while it resting in a lagoon. A very detailed account of the case was written up by Heuvelmans (1968) and what I’ve written here is mostly based on that account. Shuker (1991) and Newton (2005) provided further information. [Adjacent image by eternalsaturn.]


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Wrecked on the Great Barrier Reef with his family and Australian friend Henk de Jong, Le Serrec and family had bought a motor boat and had decided to spend three months on Hook Island (one of the Whitsunday Islands). They were all crossing Stonehaven Bay on December 12th 1964, when Le Serrec’s wife spotted a strange object on the lagoon floor. It proved to be a gigantic tadpole-like creature, estimated to be about 30 ft long. They took several still photos, gradually moving closer. Eventually, Le Serrec and de Jong plucked up the courage to approach it underwater in order to film it. It proved larger than first thought, with its estimated length now increasing to 75-80 ft. It didn’t move and they suspected it might be dead, but just as Le Serrec began the filming it opened its mouth and made movements toward them. They returned to the boat and, by the time they got there, the creature had moved off.

A large pale region interpreted as a wound was visible on the right side of the tail, and it was suggested that this (perhaps – they speculated – caused by a ship’s propeller) had caused the animal to take rest and refuge in the shallow bay. The eyes, located on the top of the head and well away from the front of the snout, were pale and possessed slit-shaped pupils. Mostly black in colour, the animal had brown transverse stripes and its skin was smooth in texture. It possessed no fins nor spines of any kind and they didn’t see teeth inside the white mouth.

Heuvelmans (1968) reported that he had done some checking on Le Serrec and found that “he had left unpaid creditors in France and did not seem very trustworthy” (p. 533). Coleman & Huyghe (2003) stated that he was wanted by Interpol. Character assassination of this sort is argued to be irrelevant by some, and maybe it is. On the other hand, there are good reasons for thinking that people with a track record of being untrustworthy really are untrustworthy. Ivan Sanderson had been contacted about the story in February 1965 (Le Serrec had initially approached the American media in order to get the best price for the images) and had concluded that the object might be either a plastic bag used by the US Navy “for experiments in towing petrol”, a deflated skyhook balloon which had become covered in weed, or a roll of cloth which had been tied together in places (Heuvelmans 1968). These are weirdly specific suggestions and don’t seem like the most sensible possibilities to me: what about the more obvious idea that (if not a real animal) it was a custom-shaped expanse of plastic sheeting, weighted down with sand?

Sanderson later suggested that the creature might be a giant synbranchid, or swamp eel*. Synbranchids are long-bodied acanthomorph teleosts, mostly of freshwater and estuarine habitats, well known for their ability to breathe air and undertake terrestrial excursions. However, they’re small (generally less than 60 cm long) and are eel-shaped, not tadpole-shaped, so this doesn’t look like a sensible idea either. Pressed to propose a ‘real animal identity’ for the creature, Heuvelmans noted in a magazine article that it could be “some kind of gigantic eel-like selachian”, which would be a huge deal if correct.

* I haven’t seen Sanderson’s article – published in True Magazine – and am going from Shuker (1991).

However, Heuvelmans (1968) actually favoured the idea of plastic sheeting weighed down with sand. He noted that the position of the eyes was highly suspicious given that most vertebrates either have their eyes on the sides of the head, or nearer the snout. Arguments like that don’t really count for much though, as unknown animals are allowed to have their eyes wherever they like, and – anyway – there are vertebrates that do have eyes positioned similarly to those of the Hook Island monster (like mastodonsauroid temnospondyls... yeah, maybe it’s a late-surviving, limbless mastodonsauroid).

The last time I published this article (2008), some aggressive commenters claimed with misplaced confidence that the ‘creature’ might actually be a tightly bunched shoal of fish. I think that this idea is an immediate non-starter, for three main reasons. (1) The edges of even the most tightly bunched fish shoal are ‘messy’, lacking the straight, obvious edges seen on the Hook Island monster. (2) The shoals don’t become organised into something as neat-looking as the Hook Island ‘monster’: the ‘monster’ has an obvious fat head/body and long, gently tapering tail, while even the most tightly packed, monster-shaped fish shoal is far more amorphous in form. (3) Fish shoals are dynamic and constantly changing shape and position, whereas Le Serrec’s photos show that the object was pretty much stationary while he was taking the photos.

There are other photos

While the still photo shown at the very top of this article has been reproduced a lot, some other images haven’t been. One (shown here on the left) shows the creature at closer range, and from a different angle. Another (shown here on the right) shows the head as seen directly from the front, at much closer range. It shows clearly that the white eyes you can see on the top of the head really are meant to be the eyes, but its wavy, broken outline provides further support for the idea that the creature is hoaxed, as the wavy outline shows clearly that the edge of the ‘creature’ is partly overlapped by sand. Ok, you might say that the creature had partially buried itself in the sand, and indeed Le Serrec reported that this was indeed the case. But in at least four spots it looks like someone has placed handfuls of sand on top of the edge of the creature: exactly what you would do if trying to weight down a monster-shaped sheet of plastic.

The final piece of evidence demonstrating that the whole episode was a hoax comes from the fact that, in 1959, Le Serrec had tried to get a group together on an expedition that would prove “financially fruitful”, and that he had “another thing in reserve which will bring in a lot of money… it’s to do with the sea-serpent” (Heuvelmans 1968, p. 534). Incidentally, the film supposedly taken of the creature revealed nothing.

Did Le Serrec inspire Heuvelmans, or did Heuvelmans inspire Le Serrec?

One last thing: when most people think of sea serpents, they generally imagine immense, snake-like creatures. Where did Le Serrec get the idea of a giant tadpole monster from? As a kid, I always thought that Le Serrec was inspired by ‘yellow belly’, a marine cryptid hypothesised to exist by Heuvelmans (1968) and described as shaped like a tadpole, 60-100 ft long, marked with black transverse bands on its sides, and restricted to the tropical waters of the Indian and Pacific oceans [my own, c. 1988, effort to reconstruct yellow belly shown in adjacent image]. Given that Heuvelmans first published his ideas on ‘yellow belly’ in 1965 (when the French-language precursor of In the Wake of the Sea-Serpents, Le Grand Serpent-de-Mer, appeared), while Le Serrec took the photos in December 1964, this can’t be possible – can it?

I wonder if Heuvelmans had published a description of ‘yellow belly’ prior to 1965, and that this description had been used by Le Serrec in making the hoax. So far as I can tell, however, Heuvelmans did no such thing. But could Le Serrec have seen Le Grand Serpent-de-Mer in early 1965, and just lied about the date of the encounter? That would require some detailed investigation (you’d have to show, for example, that Le Grand Serpent-de-Mer was available prior to March 1965, and that Le Serrec had gotten hold of a copy). What about the opposite idea: that Heuvelmans had been inspired by the Hook Island creature when coming up with the idea of ‘yellow belly’? This would assume that Heuvelmans had initially regarded the Hook Island creature as genuine, and there’s no indication of that (it’s not impossible, however). Furthermore, Heuvelmans seems to have based ‘yellow belly’ on several other, clearly identified cases (dubious and ambiguous cases (see Magin 1996), but clearly identified nonetheless).

It was reported in 2003 that Le Serrec has been found alive and well and living in Asia, and there were apparently plans to interview him about the case. That might be interesting but, regardless, the Hook Island case is undoubtedly a hoax, albeit a pretty good one I think.

For previous Tet Zoo articles on sea monsters, see...

Refs --

Coleman, L. & Huyghe, P. 2003. The Field Guide to LakeMonsters, Sea Serpents, and Other Mystery Denizens of the Deep. Tarcher/Penguin, New York.

Heuvelmans, B 1968. In the Wake of the Sea-Serpents. Hill and Wang, New York.

Magin, U. 1996. St George without a dragon: Bernard Heuvelmans and the sea serpent. In Moore, S. (ed) Fortean Studies Volume 3. John Brown Publishing (London), pp. 223-234.

Newton, M. 2005. Encyclopedia of Cryptozoology. McFarland & Company, Jefferson (N. Carolina) and London.

Shuker, K. P. N. 1991. Extraordinary Animals Worldwide. Robert Hale, London.

Darren Naish is a science writer, technical editor and palaeozoologist (affiliated with the University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs but has an avid interest in all things tetrapod. His publications can be downloaded at darrennaish.wordpress.com. He has been blogging at Tetrapod Zoology since 2006. Check out the Tet Zoo podcast at tetzoo.com!

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