im sure ill get flamed for this but here it goes....

  • We are currently upgrading MFK. thanks! -neo
No there not, wish I could remember the name of what you call sharks that are, it is really bugging me now.

Nurse sharks are classified as carpet sharks (Orectolobiformes) along with the wobbegong, epaulette and even the whale shark. Is that the name your thinking of?
 
No there not, wish I could remember the name of what you call sharks that are, it is really bugging me now.
I think you mean the lamniformes (mackerel sharks) and carcharhinidae (requiem sharks) but any open water shark needs to constantly swim or they sink. Even the requiems can rest on the bottom in the right current. The problem is not so much breathing but rather that they don't have swim bladders.
Your nurse might munch those smaller fish but hey, you do what you can.
How did it break the tank?
Since sharks excrete urea directly through the skin you might want to do daily ammonia checks.
 
yea i just read that, they rely on their liver for a bit of boyancy, and they all sink when resting. apparently sand tiger sharks gulp air to keep them afloat a bit better too
 
Requiem sharks was the name that I was looking for. I knew in the right current the can rest on the bottom but in most tanks that the common hobbiest has they aren't really able to recreate that or really have a big enough tank for them to swim in.
 
Nurse sharks are interesting animals for of several reasons. It is not true that that all sharks need to swim in order to breath, and when they cannot for whatever reason, they die. Sharks breath primarily by using a ram-jet ventilation system, which requires that they be swimming. Some sharks, however, have a second system based on respiratory pumping of water. Nurse sharks can switch to this respiratory system when they are at rest, saving energy and the neccesity to swim to get plenty of water over their gills. This is especially important for bottom dwellers such as Nurse sharks. Nurse sharks do not attack humans, despite claims to the contrary; they are one of the most docile animals in the sea.


http://animaldiversity.ummz.umich.edu/site/accounts/information/Ginglymostoma_cirratum.html


Nurse sharks are light yellowish brown to dark brown, with or without small dark spots.


The mouth is filled with rows of small, serrated teeth for crushing hard-shelled prey.

Generally slow and sluggish, nurse sharks spend much of their time resting on the ocean's bottom.

Because this shark can pump water over its gills, it does not need to swim in order to breathe.

If it must move, the nurse shark may even use its large front (or pectoral) fins to “walk” along the ocean floor.

Unlike many sharks, this species is non-migratory—the nurse shark adapts to cold by becoming even less active!

Visitors often think this shark is in trouble when they see it lying on the bottom of the Open Ocean exhibit.

If you overhear people commenting, explain that the shark is fine. Point out the movement of the gill slits as the shark pumps water over its gills to obtain oxygen.


http://www.aqua.org/animals_nurseshark.html
 
i can guarentee nurse sharks DO sometimes attack people. they are not a completely harmless fish
 
i can guarentee nurse sharks DO sometimes attack people. they are not a completely harmless fish

This is usually because of a person bothering the fish or stepping on it, not out of hunger or anything. I wouldn't call it attack as much as I would self defense...something most animals do.
 
there was an attack from a full grown one a couple of years ago that killed someone. i dont think they were bothering it though. a lot of people would leg it in england at the sight of a shark
 
I think you mean the lamniformes (mackerel sharks) and carcharhinidae (requiem sharks) but any open water shark needs to constantly swim or they sink. Even the requiems can rest on the bottom in the right current. The problem is not so much breathing but rather that they don't have swim bladders.
Your nurse might munch those smaller fish but hey, you do what you can.
How did it break the tank?
Since sharks excrete urea directly through the skin you might want to do daily ammonia checks.

I thought he was asking the name of the sharks that can rest on the bottom...oops.

Nurse sharks also have something many sharks do not have. A spiracle. The spiracle is used in sharks to provide oxygenated blood to the eyes and brain through a separate vessel. It can also help pump water over the gills. Many bottom dwelling sharks have these as do rays and even bichirs.

Requiem sharks are members of the family Carcharhinidae and many can rest on the sea bottom. Lemon, blacktip, grey reef and others have all been seen resting on the bottom. It actually takes more work for them to breath this way so they aren't really resting at all. It's not just the lack of a swim bladder either, shark gills are a lot weaker than that of bony fish and are in many species not strong enough to pump water over the gills. This goes back to the ram-jet ventalation that sharkguy was talking about. Some shark really do have to keep swimming in order to breath, the lamnids are a great example of this.
 
there was an attack from a full grown one a couple of years ago that killed someone. i dont think they were bothering it though. a lot of people would leg it in england at the sight of a shark

Well there is really no way of knowing is there? ;) I'm sure once in a great while they do bite people for reasons other than self defence but I think the majority of the time with these species it is the human's fault.
 
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