Sunday, February 10, 2013

When should we see sea serpents?

A thought experiment... I'm one person who suspects there is still, after all these years, a grain of truth behind the sea's most magnificent legend, that of an unknown creature misleadingly but universally called the "sea serpent."  There are many hundreds (maybe thousands) of sightings, and, in the consideration of two experts writing decades apart, around 350 interesting ones.  

Sea serpent reports have definitely dropped off in recent decades, to less than one per year.  But how often should they be sighted, if there is a real animal involved?

I caution at the outset there are no good numbers for many of those figures, and I chose numbers that seemed reasonable and made the math simpler. So this is a simplification of a complex situation using arbitrary numbers, but one has to start with something, and the problem of how often humans might be expected to spot a possible sea serpent niggled at me until I had to try something.
 

The world’s oceans cover139,000,000 square miles (statue miles). A variety of Web sources give figures of 12,000 to 90,000 vessels on the oceans at any moment.  Let’s use a high number, 50,000, which covers (we are presuming) everything large enough to have a lookout (small pleasure craft, for example, would be excluded for the moment). A lookout can see 1.17 times the square root of his or her eye height above the ocean, in nautical miles (note the diversion in units here: you'll see it's not enough to matter), so from an arbitrarily chosen 49-foot spot on a mast or bridge that’s 8.19 miles.  An object rising above the water essentially raises the horizon: you could, in perfect conditions, spot the head/neck of an animal rearing 9 feet out of the ocean 8.19 + 3.51 miles away, or 12.7 nm.     
In practice, no one can identify much of anything at that range, especially if sea serpents are sometimes wont to stick only the head or a small section of body or neck (if it has a neck) above water. Let’s say you can definitively identify a sea serpent (assuming there is such a thing) and rule out debris or known marine life at one half a statute mile.   There’s no way to calculate the average eye height of the lookouts of all the ships at sea (and not every ship will have a lookout at all), not to mention who’s carrying what binoculars, so this business quickly gets rather silly, but if we assume, say, a ship can watch a circle of ocean a mile in diameter (area 3.14 miles) for sea serpents, and there are 50,000 ships with lookouts, then you get a figure of 157,000 square miles being observed.  If there are 139 million square miles of ocean, then 1/874th (0.1129 percent) of the surface would be under observation, and a population of 1,000 sea serpents showing themselves for, say, five percent of their time at the surface (it could be far lower), 20 might be visible somewhere, and if they are identifiable in an area of 3.14 square miles, you get an area of 62.8 square miles, or 1/221338 the area of the sea (or 0.0005 %) showing sea serpents at any time, and if you try to calculate the likelihood of these areas intersecting  the other the math goes from extremely hypothetical to absurd (any readers care to take a crack at it?).  Actually, it’s worse than this: half the time it’s dark, a considerable percentage of the time there is a sea state that makes identification harder, or it’s raining, or it’s foggy, and the fact that lookouts on the open sea spend most of their time looking forwards… well, you get the picture.  Or no one gets any pictures.

Comments and brickbats welcome.

16 comments:

Laurence Clark Crossen said...

There have been many reports and there are many reasons they would be elusive. Whether they are basilosaur-like or plesiosaur-like they would be air-breathing and require surfacing. However, my model of a basilosaur-like sea-serpent has extremely high speed of locomotion. The plesiosaur might not be prone to disporting itself playfully on the waves.

Matt Bille said...

Whatever the hypothetical creature we call the sea serpent actually is, it's definitely not prone to disporting itself much :)

Laurence Clark Crossen said...

By much you cannot mean frequently. You can only mean it does not pose for long. I think that plesiosaurs can sink straight down and the reports have the longer sea serpents moving at extraordinarily high speed. Plesiosaurs could not have moved very fast and must rely on stealth accounting for the mere fleeting glimpses.

Laurence Clark Crossen said...

Less frequently than whales because they are solitary like pumas.

Laurence Clark Crossen said...

We should see sea serpents when there are no modern/motor boats around as they seem to be averse to them. The New England Sea Serpent was comfortable hanging around crowds of people and many sail boats for many days close to shore. Why does this not happen any longer?

Laurence Clark Crossen said...

Are you being conciliatory about the possibility of sea serpents? Or are you inviting help to show they should have been photographed by a professional wildlife photographer? A person who could not have achieved success in his profession if he was at all apt to entertain the possibility?

Matt Bille said...

Clark, I personally think at least one type, a giant eel or eel-like fish, weill eventually be proven. Not sure about the classic "longneck."

Laurence Clark Crossen said...

All it would take is a long necked basilosaur.

Laurence Clark Crossen said...

Conversely, it could be a basilosaur that is reported as long necked to conform to traditional expectations.

David Evans said...

If we take your figure of 1,000 sea serpents and 5% of them visible at any one time, that's 50 visible, not 200. That equates to 1 visible sea serpent in every 2,780,000 square miles.

The next question is how much sea does the merchant fleet have under observation during a 12-hour day? Assuming an average speed of 10 knots, i.e. 11.5 mph, each ship will observe a strip 1 mile wide by 138 miles long, or 138 square miles. The fleet of 50,000 ships will observe 6,900,000 square miles which should on average contain more than 2 visible sea serpents. So the fact that we don't have 2 sightings per day suggests that there aren't 1,000 sea serpents on the surface 5% of the time. Or that one of the other numbers is wrong.

Of course, as others have pointed out, it's not so simple :)

Laurence Clark Crossen said...

Less than 5% of the time because they would only be fleetingly visible before they hid from the ship. They do not like the motors.

Matt Bille said...

Clark, running over the reports that come to mind, I don't think we don't have any data to be sure about sea serpents and ship noises... they sometimes ignore vessels or (occasionally) act curious about them. As to basilosaurus... I doubt it. The known whales were evolving away from visible necks and serpentine forms.

David, thanks for the math corrections. I'm going to have to do this again with an actual math expert involved :)

Laurence Clark Crossen said...

That earlier whale fossils had longer necks and more serpentine forms does not mean they do not still survive. The appropriate niche may likely still exist. Whales would not evolve away from a niche that has continued to exist. In just one cut for a road they found four new earlier whales to have existed 5 mya later than had been thought. I think this tends to show our sampling of the fossil record is very sketchy.

Laurence Clark Crossen said...

Let me get clear about your positions. Everyone can tell you are the most conservative cryptozoologist. You are also very averse to prehistoric survivors. I remember you have suggested that some sea serpent reports may be accounted for by a new whale species. I think that the fact that the kraken proved to be a real creature, the giant squid, provides good reason to suppose the sea serpent may be a real creature also.

Matt Bille said...

Well, anything we discover is likely to be a kind of prehistoric survival: species don't pop out of nowhere. The idea of surviving Mesozoic reptiles is suspect to me, though, because we have hundreds of fossils of many species spanning over 100M years and then they just stop at the K-T boundary. That's a pretty good sign of extinction. If we theorize it could be a deep-sea eel that rarely comes to the surface at all, then we're less likely to have a carcass or (if it evolved fairly recently) even a fossil. There are some good reports where an eel can't possibly fit, and those are harder to figure out. Bruce Champagne floated the interesting idea that the beaked whales have independently produced an elongated form, and I wonder about a large long-necked seal in some cases.

Laurence Clark Crossen said...

I think that either a plesiosaur or a basilosaur would be able to locomote on land sufficiently to avoid beaching while alive. Bousfield and LeBlond notice the vertical flexure and think it is a reptile. My model is mammalian. I accept provisionally that the many reports of multiple vertical flexures are correct. I wonder if a basilosaur could have locomoted by multiple vertical flexures? By this I mean, more flexures than a whale. Whales have a flexure point at the neck, mid-back and tail for a total of three. Sea serpents are described utilizing more than that. If the currently accepted concept of a basilosaur's body is too robust, then the part past the torso may have been capable of more flexures. What do you think?