Suspicious shark sighting - what was it up to?

[WKD]

I've just come back from the Great Barrier Reef and have a shark related question, which has been bugging me. So here goes....

We were out on the outer reef and saw several white tip reef sharks mooching around, nothing strange there, but then we saw one lying on the bottom, in a sandy patch, not moving, no apparent injury, looked normal except for the fact it wasn't moving, not even a little fin twitch, nothing.

Now, I thought that sharks had to move continuously to keep water filtering through the gills, if that is not the case then mystery solved it was just having a sit down. Alternatively, maybe it was parked in a current, thus it could stay still and water still go through its gills.

Of course there is the chance that it may have expired and that's where it landed, but it looked healthy and its eyes didn't look dead, not that I got too close to it, wouldn't want to startle it and loose a chunk of flesh. And don't fish float when they die?

So if anyone knows if this behaviour is normal and why it was doing it or can tell me if the poor thing had snuffed it, I would appreciate it.

Thanks

 

[Jimmer]

I believe white tip reef sharks are one of the few species that can lay down and "pump" water through their gills. It makes me wonder if that is why their pectoral fins appear pointed more to the side, than some other species that appear more downward.

 

[robint]

yes, there are several species of sharks who can "sleep" on the bottom. They do NOT need to keep moving in order to breathe. Nurse sharks are the big species in the caribbean which are seen lying on their bellies under coral ledges. In California, horn sharks, swell sharks, and angelsharks alll lie on the bottom. In Hawaii and other places in Pacific tropics you can see both white tip and black tips on the bottom just hanging out during the daytime.... they are usually only actively swimming at night.

 

[LIVES4SHARKS]

Lemons will also take a break on the bottom.

Carolyn:shark2:

 

[archman]

That is an AMAZING picture.

 

[Pug211]

I love reading and learning new things on this board. Great picture

 

[LIVES4SHARKS]

I will hopefully be seeing that next week. This was from last years Tiger Shark expedition in the Bahamas with Shark Diver Magazine. The lucky photographer gave a great dive report.
http://www.sharkdivermag.com/tripreport-tigershark1-07.html
I will be leaving 11/14 and will be back 11/22. We expect to see and dive with Tigers, Lemons, Great Hammerheads, and of course Reef and Nurse Sharks.

I will be sharing this with y'all when I get back!

Now back to the thread...sorry about the hijack!

Carolyn:shark2:

 

[divepirate]

hey wkd,
i was a shark feeder in the bahamas for over 8 years and saw various behaviors that maybe are not documented.. i have seen reef sharks lie on the sand for minutes, and then 'get up' and swim around...they definately do not need forward motion to keep going. i have had them in my lap, seemingly resting for as long as i wanted, just kept stroking them like a big dog..sometimes they decided to get up and go, other times they felt a distraction, and would take off, at varying speeds!
i have also seen lemons and tigers doing the same. (ie lying motionless on the sand).
hope his helps.
cheers

 

[WKD]

Thanks for that.

I'm glad it wasn't dead or sick!

This was the first time I had been in the water with sharks, admittedly only small ones, and I surprised myself at how not scared I was, one swam past really close, checked us out then wandered off over the wall. I was more scared of the Titan Triggerfish who was apparently nesting and didn't appreciate the intrusion, can't blame it for trying to bite our fins really, but it might have put out a sign!!!!!!:gator:

Thanks again

 

[Shark Doctor]

Here's something else to look for, and maybe be on the alert for some REAL excitement. Next time you see a whitetip (especially) lying still on a sandy or grass patch, try and check out the pectoral fins to see if you can detect any fresh wounds... Often in this species, and ESPECIALLY in nurse sharks, females (who would have bite marks on the fins) and "exhausted" males will often lie very still while "recovering." Obviously there are certain times in the year when this is likely to happen, but if you are in the right place at the right time, you might have some real tales to tell!!!