Shark Webcam, courtesy of Shark Lagoon
Sharks a bit of a touchy subject for me (as you can probably tell from previous posts). I believe that sharks are an animal that inarguably need our help- the issue is, most people don't like them. Anyway, more ranting for another time. It's about time that I actually record some observations of our sharkies. I found this webcam a few days ago, and let's just say, I'm very excited. Although, I can't promise the same sort of observations I can make with Nemo and Wake (I doubt I'll be able to tell these sharks apart), what makes this webcam particularly interesting is the sheer variety. On first glance I can spot, some Black Tip Reef Sharks (my favorite incidentally), White Tips, some sort of Saw Shark, a number of Rays, and possibly a Nurse Shark.
What I noticed off the bat was the speed that some of these sharks maintain (especially the reef sharks). This made it blatantly obvious when two of the sharks weren't moving at all).
As you can see from the previous image, two of the sharks (the Saw Shark, and what appears to be a Nurse Shark) have remained dormant. This probably brings to mind the myth that all sharks need to keep swimming, so as to avoid hypoxia. However, this assumption isn't strictly true. Although, some sharks need to keep swimming (this, too is being debated, as some of these sharks have been seen basking for short periods of time), most
sharks are able to 'pump' water from muscles around their mouth over their gills. A more pertinent reason why many sharks spend large periods of time swimming, is their lack of a swim bladder: bony fish have a swim bladder which allows them to move up and down (deeper an shallower waters). Sharks don't have this organ. Thus in order to move up and down they use their fins, and use pressure columns.
The black tips seem very busy, zipping all around the tank. They also appear to move much quicker than, say, Wake and Nemo in the Vancouver Aquarium- who take life at a much more leisurely pace. What's interesting is, as far as I can tell, there isn't any fish in the tank for the sharks to hunt, so why are they swimming so hectically?
The Saw Shark is finally inching itself forwards.
There seems to be only one Saw Shark, so I'm going to give it a name.
Solomon the Saw Shark: has a certain ring to it.
Hello Solomon. His 'saw' is fascinating, nothing like the reef sharks. I'll have to look into the purpose of it: or perhaps it just a display adaption.
Solomon is on the right hand side of the screen. Black tip reef shark.
Notice how different the tail of a shark is, when compared with on of the Belugas. Belugas bear down on the water with their tail, thus it is parallel to the water surface. However, sharks glide through the water, using their tail in a more snake-like movement, thus their tails are perpendicular to the water surface.
Heading towards the camera. I still can't tell what they are trying to do, as there is nothing really to try and capture. It is likely, however, that reef sharks are one of those sharks that find it difficult to use the muscles around the mouth, to push water over their gills.
Three sharks seem to be congregated near the webcam.
I believe the shark surrounded by two black tips is a white tip reef shark... I could be mistaken.
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