Well, let us pay tribute to a shark people for the most part don't even know about.



Welcome to the Cookie Cutter Shark! This is as big as they get.
What is worst is this is what they can do to you...



That is a bite taken out of a bottle nosed dolphin.



Notice how this fish has a sucker like mouth with teeth.





These things have been known to attack humans and at least one fatality recently has been directly attributed to these fish. Several others attacks are suspected. One oceanographer recently was mobbed by these fish and lived to tell about it. They are considered as Man Eaters and also Very Dangerous.



This was a whale unfortunate enough to run afoul of a school of cookie cutter sharks. They were responsible for disabling the sonar on submarines and underwater cables by biting through the neoprene insulation used on cables and to protect submarine sonar domes.

Another odd thing about these sharks is they are bio-luminescent and glow green on their underbellies. Fortunately they only inhabit warm open waters but have been known to prowl shallower reaches. They also swarm and are not hesitant to attack prey MUCH larger than themselves and do so with the aggression of the Brown Bull Shark. A big cookie cutter will reach about 18 inches. They take tennis ball sized chinks out of their victims!

How is this for freaky?

Very good to know. Thank you for sharing your information with us all.

I think it is quite facsinating, and I thought pirahanas were wild.

I wonder if they would be hard to take care of.

I would really like to get some jellyfish, but they would be impossible to keep alive.

Actually I am installing a jellyfish tank in the Sketcher's world head quarters!

They are not impossible but you have to have what is called a Kriesel tank to keep them in. You also have to bear in mind they are the only thing you can keep in the tank becasue everything else that goes in is food for the jellies and you cannot mix species. Also some can kill you! There is one in Australia that is only about the size of a large marble. If it stings you it was nice knowing you! The Box Jelly everyone is so scared of is about the size of a volley ball. Jellyfish like Crystal Jellies tend to stay small. There are tropical jellies that don't get any bigger than about four inches in diameter. I actually have wanted to get my hands on fresh water jellyfish (THEY DO EXIST) and they only get maybe an inch in diameter!
The problem is jellyfish are a trend like everything else. Unless you are prepared to spend real money setting up to keep jellies (like you MUST have a chiller on the tank for starters!) they are not for everyone. You can buy jellyfish tanks on the market but they are really in my opinion too small and limiting for the animals people want. The tank I am installing is ten feet across, five foot tall, two feet front to back with a curved face that adds a foot to the front to back dimension at the widest point. Home units are good for the smaller species but we are housing Pacific Sea nettles and they can get almost four feet long and about ten inches in diameter. Their tentacles can reach ten feet long when filly extended. Their sting burns like hell too!
Also Jellyfish are very fragile! They have to be handled very cautiously.

So you're telling me that there are sharks that glow my favorite color and can take out sonar? And you're just telling me now?

That's awesome on so many levels.

And they only get 18 Inches long.

One was suspected to take a plug out of the vulcanized rubber of sonar cover on a US sub way the hell down. But the plug was 6 inches deep and 14 inches across so they may get a bit bigger than we know.

Yet another reason not to go swimming in the local public pool.

Cool! Thanks for the info. I thought it would be too expensive to keep jellyfish in a home aquarium, but I'll look into it a bit more.

They're ugly but fascinating.. I had never heard of them.. I love sharks.. Thanks for sharing...

Depending on what coast you are on you can get moon jellies which are easy to keep (pacific ocean). A warm water jelly that doesn't get too big is called the Mauve Stinger but word of warning, these things pack a very fuqued up wallop. Now there is one called a bubble jelly that stay very small, and are relatively easy to keep in a smaller kriesel but I would not go anything less than 30 gallons! Shoot for about sixty! The filtration is very basic actually for jellies. A wet dry filter with eurobags and a UV sterilizer is all you need. You must make sure that you have a chiller to keep the temp from going too high and a heater to make sure it does not get too low. Even the less sensitive ones do not tolerate temperature changes of 6 degrees per hour at all well. Usually they die. Another concern is aerating the water too much. A intake leak on the pump can kill your jellies becasue the gasses that saturate in the water will accumulate in the jellyfish's bodies and form gas bubbles which will do them in. Unless you use a settling refugeum do not use any kind of protein skimming since the water is saturated with air or ozone to help break up protein mass.



These are lake Palau bubble jellyfish.
There are varieties of similar subspecies that are black, light blue, and even purple.

They also feed on the same phytoplankton supplements you would feed reef invertebrates.

Moon Jellies you can feed baby brine, zooplankton, and chopped up fish.

Pacific Sea nettles need to be kept in 56 degree water. Needless to say some varieties need a very specialized tank. Because of the temperature requirements on the tank I am installing I may have to use up to six horsepower of chiller. I still am doing homework deciding on how much overkill I want built into this system. I always design around catastrophic failure. That way if anything does happen out of the blue the system has redundancies to keep the jellyfish alive! That and anything else I design an Aquarium or any enclosed environment for!