I too am curious to know more about the identity of the 22 foot freshwater shark that was allegedly filmed. The sharks that are known to venture into freshwater, as well as anadromous fish (fish such as salmon and eels that move back and forth between fresh and saltwater) and freshwater elasmobranches (cartilaginous fish) such as sawfish and some rays, have special adaptations that allow them to cope with problems of osmotic pressure. The simplest way I can put it is that basically there is a difference between the “saltiness” in the fish’s body and the water in the environment, which affects the pressure between the two and so the amount of water and salts in the body absorbed from, or lost to, the environment.

This osmoregulation is key for any fish going between fresh and salt water, since without it a saltwater fish in a freshwater environment will, due to differences of osmotic pressure, experience a huge influx of water into their system. This water will tax the internal organs, in particular the kidneys, damage cells, and cause large amounts of salt to be lost to the environment. This is why without certain adaptations, saltwater fish in freshwater will die. For instance, in bull sharks, there is usually a huge reduction in the sodium and urea content of their systems, as well as increased kidney activity. There are a range of osmoregulatory strategies that fish species that go between freshwater and saltwater use to deal with this challenge.

The problem I see here, is that there is no known saltwater fish that large (22 feet), which is known to live in or enter freshwater on any kind of regular basis. Great white sharks have been on reported in freshwater, but in my opinion these are freak occurrences for this species. There is no evidence that I know of that great whites have shown they demonstrate any particular tolerance for the differing salinity involved, and they are certainly not currently known to regularly enter brackish or freshwater environments. A freshwater environment could very well kill them before too long. If the reported shark was a great white, it would be very interesting indeed.

okay it was a whale shark, but what if that was the second fish they saw? what if the megalodon or whatever, it was, they saw it form the hellicopte?

i mean they can’t just say it’s mistaken iden.

cause of that.. any marine animal could go to that waters…

just that they went at the wrong time.

i’m not just going to say it’s mistaken just cause they didnt’ see it.. they can’t talk speak for anybody else.

Don’t see why A MEG in that area is so unbelievable.

Disappointment is tempered by the fact that the “quest” goes on.

I think the monster great white report from New Zealand is a genuine mystery, though some other gigantic shark reports I’ve read may concern basking or whale sharks.

Largest C. carcharias landed and accurately measured: under 7m. (See Ellis and McCosker, Great White Shark).

This was also in the range of the largest sharks reported from the extensive study of great whites made off the Farallon Islands (per Susan Casey’s book The Devil’s Teeth).

One expert’s estimate from bite marks on a whale off Australia: almost 8m. Recently announced (estimated) max for prehistoric C. carcharias (not the distantly related Megalodon): 9.1m

A great white approaching the size of the largest orcas is big enough to be called a “monster.” One of the big names in ecology, Paul Colinvaux, wrote that the known size of the great white shark is about as large a predatory fish as a modern aquatic ecosystem will allow.

Certainly an “outlier” great white of 7 to 8m might be reported as considerably longer by a startled witness.

So what’s really out there… ?

I believe he is referring to the greenland shark in the episode “Jaws in Illinois”.

I live in San Diego and I know people who have gone down to Baja for vacation and taken plenty of pictures of whale sharks down there. When the episode first started, I said I hope they aren’t going to find a whale shark. DING DING, I was right.

From the sky you could tell it looked like a whale shark too.

Oh well! I do have one interesting tidbit. I had a neighbor who was a marine welder back in the 60s and 70s and use to work out in Baja. He said on more than one occasion when he was out there he saw a “hammerhead” YES a “hammerhead” that was bigger than his boat. The boat was over 35 feet long. He said this thing was a monster. This guy was very, very credible. I believe there definitely are some huge undiscovered sharks out there off of Baja. Just a matter of patience and time.

Speaking of the Whale Shark. I thought it was pure theatrics that they “dove” on it. When the footage from the airplane showed the big flat snout, I almost shouted “whale shark” at the screen. To my knowledge, big carnivous sharks all have streamlined pointed shouts.

The only bright spot was seeing Steve Alten (if you haven’t read his books yet, start now before the latest in the MEG series hit bookshelves this summer).

Once everything was said and done with Mega Jaws (what a title!), all we got were two hyper scuba divers and one tired pilot. Oh and this bored viewer.

One of the suggestions he had for trying to get an actual sighting of Champ was to pick a spot likely for Champ and then go spend time there for many occasions, at the same time of day, everyday that you can. The idea being that if you make yourself part of the normal scenery in an area, an animal such as Champ might come to see you as more of the background rather than something that stands out, and be more likely to come out of the water in your presence.

My thought last night as they raced speed boats back and forth trying to close in on this predator was whether they wouldn’t have had better luck just positioning 3 or 4 boats in the areas and sitting idle for the bulk of a day or two. Blend in, be part of the normal surface area (and quietly without motors running), and see if something might not come to the surface, either out of curiosity or just because it was used to them being there for a long period of time.