Teeth of the Tiger

Although I've already posted about tiger sharks, it was a little tough to see because all the pictures were taken at night.  Not so anymore.

This handsome fellow, measuring in at 302 centimeters (about 9 feet 6 inches), was caught on our deep line that we set last week.  A deep line is essentially the same as a longline (discussed in the previous post about tigers) except instead of being stretched a long ways horizontally in shallow water, it is stretched vertically in much deeper water, about 750-800 feet.  We made numerous attempts to get big tiger sharks for a big game fisherman/conservationist named Guy Harvey.  He was at the lab along with a few big-name shark scientists shooting the end of a documentary on tiger sharks.  For those that don't know, Guy Harvey is HUGE in the southeastern U.S.  The people from Florida here acted like they were 14 year old girls meeting JT or something.

 That's Guy Harvey with the camera.  He shoots most of his footage himself and as you can see he gets right on in there.  For a born-rich adventure seeker, he's actually a really nice guy and completely devoted to marine conservation, so it was pretty cool to meet him and hang out with him.  Also didn't hurt that he has a resort and restaurant on the north island, which he brought us to and treated us to a fantastic dinner.

There was also a scientific purpose to catching the shark.  In this picture you see two of the scientists on Guy Harvey's team fixing a satellite tag to the shark's dorsal fin.  The tag will record data on sunlight, water depth, and a few other factors and using all that, the scientists can figure out where the shark swims.  After about 6 months, the tag pops off and floats to the surface and broadcasts the data.

I don't actually have anything to say here, this is just an awesome picture.  The release got a little hairy; instead of swimming down and away, which is what normally happens in these situations, this guy decided to cruise around at the surface for a while, where all the people happened to be.  Guy Harvey's camera man got a phenomenal shot when the shark swam within inches of the camera and opened its mouth real wide.  It swung around after that and came right at me and another volunteer.  I have a video of the whole thing, about 3 and a half minutes long, but it won't load into the post for some reason.  It's pretty wild, so if you're interested shoot me an email and I'll try to send it to you.

Incidentally, while in the process of writing this post, which took over a week, we caught another tiger on a deep line we set for the students from Eckerd College.  She was a big momma...

She clocked in at 336 centimeters (a shade over 11 feet), but she actually should have been about 20 centimeters larger; the end of the tail fin had been bitten off, most likely during mating.

As you can see, this shark is almost as big as the boat she is tied to.  If you look at the picture of the other shark from last week, the difference of only about 30 centimeters makes a tremendous difference in the size of the shark.  Not only is it obviously longer, the difference in width is enormous.  The mouth of this one seemed to be double the size of the smaller male.  It's amazing how much of a difference a few centimeters makes.

There is also a picture floating around of me basically giving her a hug, but I haven't managed to get my hands on it yet, so it'll have to wait until next time.

Grab the Bull by the Horns

Ladies and gentlemen, the bull shark.

As much as I've tried to learn you something about how sharks are not nearly as bad as they are portrayed by people, the bull shark does actually merit extreme caution.  Growing up to over 11 feet long, bull sharks are set apart from other sharks in that they have very volatile personalities.  Whereas most other shark species have, for the most part, predictable behaviors in certain situations, the bull shark can go from a fantastically exciting thing to see to truly frightening in a heartbeat.  Bull sharks rank in the top 3 when it comes to number of fatal attacks, just behind great whites and tigers.  However, there are some reports of shark attacks not attributed to bulls when it is likely that a bull shark was responsible. 

One very special aspect about the bull shark is that it can not only survive, but thrive in fresh water.  Bull sharks are known to swim hundreds of miles up rivers and there is even a small population of permanent residents in the Brisbane River in Brisbane, Australia.  While fascinating, this also contributes to the high numbers of attacks on humans.

Generally, I will tell you that if you see a shark in the water, don't panic, just relax, stay aware and enjoy.  The bull shark is a bit different.  If you come across one of these guys in the water, I STRONGLY recommend getting out.  Fast...

All that being said, on to the cool stuff.  This is us grabbing onto a nice 232 centimeter (about 7 feet 7 inches) male with a student from Eckerd College standing about 5 feet from his face. We caught him just off the docks on the north island using just a hook attached to a rope with a large, glowing orange ball on top so we could see where the shark went after we hooked it.  After we pulled it up to the boat, we did a quick work-up, took some DNA samples and put a Casey-tag in.  A Casey tag is a small tag attached at the base of the dorsal fin with an identification number on it.  If the shark is caught again, the tag can be removed and there are instructions on the back directing people to contact the National Marine Fisheries Service.  This way, if the shark is caught again, and the people who caught it feel like it, we can get a little data on where the sharks go.

I was the one to put the Casey tag on this guy, and if I do say so myself, it was a beautiful tag.  The way to tag a shark is to take a device, actually looks like a rolling pin with a barb on the end with the tag in the barb, and slam the barb into the shark.  It sounds brutal, but the sharks can't feel it.  Shark skin is very thick, so you really have to hit it hard and a lot of times it takes more than one shot.  Unless you're me of course; one shot, straight in, in front of a crowd of 20 onlookers waiting for me to screw it up.  But obviously I'm calm cool and collect under pressure, and as another volunteer commented afterward, I hit it "like a boss."  Thunderous applause followed and a well-deserved bow.

The whole tagging and work-up process only takes about 5 minutes, even with all the explanations for the benefit of the students in the course.  It is very low-stress for the shark and we try to get them off the boat as fast as possible.  As soon as the hooks and ropes were off, this guy took off into the the sunset, no worse for wear.  Today is your lucky day too, because there will be not one but TWO posts!  Stay tuned...