Sign in to follow this  
Followers 0
BrianBM

Temperature tolerances of GW sharks

Rate this topic

19 posts in this topic

Where seals go, GWs follow. We get more seals on LI in winter. Does anyone know if GWs can tolerate Long Island East End or SS water temperatures, for a tasty seal snack?

 

Just wonderin.'

Share this post


Link to post
Share on other sites

I know that they can maintain their body temperature higher than the water surrounding them. I would say, yes, a great white in those waters is definitely a possibility.

Share this post


Link to post
Share on other sites
Seals live inshore ... must get Cwitek into this thread. He'd know. I understand he raised GWs in a pool in his backyard. To feed his pet orca.

 

But then I felt guilty after seeing Free Willy and returned them all to the sea...

 

Most of the places that hold big concentrations of whites--southern Australia, the Farallon Islands, South Africa, etc.--are cool-water areas, although not really cold, My impression from what I've read is that they tend to thin out when water gets much cooler than 55 or so, although a few will show up when the water is at least 10 degrees cooler than that if the feeding is good.

 

So the guys who still want to wetsuit during the herring run might want to look over their shoulders from time to time, particularly if they start hearing particular music, but those who surf in Turtle Cove during February should probably worry more about wiping out on a boulder.

 

Interesting thing that they've found from archival tags is that when some of the whites migrate south after spending the summer on Cape Cod, they follow the edge of the shelf, sometimes as far south as Florida, and engage in some surprisingly deep dives. Folks guess that represents feeding behavior, and the bottom layers of water that they're feeding in is probably much colder than 55F. Good chance that it's well below 45F. So cold doesn't bother them too much, although perhaps it's tough to endure for long periods. Like a few other fish that frequently make deep dives, they maintain their body temperature a bit above that of the surrounding water, but how long they can maintain it once the water drops below 50F or so, I don't know.

Share this post


Link to post
Share on other sites

umm they track them from maine to florida ,,, and they have been caught in our waters , so yes they are out there

they regulate there own body HEAT so they hang out in colder water easily , they cant self cool so finding them in the tropics isn't common

Share this post


Link to post
Share on other sites

Check Ocearch.com for Mary "Lee" and others. These folks track GW's on the east coast and South Africa. ML was tagged in Feb 2012 at something like 3500#. You will definitely need a bigger boat if you want to meet her. You can track their 50+ sharks for various periods ofr overall since they were tagged. She is the largest EC shark on their tracker. but not the largest one they track.


Share this post


Link to post
Share on other sites

Interesting stuff. I'll have to see if they've been able to track GWs off Long Island in the Jan-Feb period, and (if so) how close to shore, where the water's likely to be coldest, they might come.

Share this post


Link to post
Share on other sites
A year or 2 ago there was a GW shark tracked to 20 miles from Shinny in mid Jan. I think the name of the shark was Mary.

Pete

 

Pete I remember that one as well. It got me started on the habit of looking at their site. Last year life guards around Flagler were given notice of a large GW in the Surfline. Closed the beaches for a while until the signal moved off. I've been told by Chet Wilcox of a few baymen clamming in Moriches in the early spring have sited fins inside the bay. After the seals have left in April or early May. With the number of seals hauled out on those bars all winter there has to be a strong scent left over. I'd hate to see LI become Northern California, for my own selfish reasons.

Pete

Share this post


Link to post
Share on other sites

I  have heard claims (and none actually substantiated mind you) that those standing on rocks in the middle of the night have had sharks around them, one real good story of wetsuiter on rock...seals seals...then no seals...quiet... and then BIG swirl at feet in black of night (f that!)....and like has been said...they can keep their temperature up...


Share this post


Link to post
Share on other sites

White sharks, like UFOs and Bigfoot, are commonly spotted where they aren't, or so I suspect. You do wonder. If a seal forage base is proliferating on Long Island in winter, the sharks may well follow. White shark's ability to regulate temperature is not as advanced as the bigger tunas enjoy, so we'll see. Seals in winter are close in shore - at least that's where we see a heck of a lot of them - and the water there will chill down more quickly then water offshore.

 

We need more tagging data. Perhaps a few of the skishers can be persuaded to carry shark tagging spears with them. ;)

Share this post


Link to post
Share on other sites
Quote:

Originally Posted by BmR5979 View Post

If they ate plovers would the dec hunt them down and kill them all. tongue.gif





What is needed is a photo of a seal chomping down on a plover. Anyone photo shop?


Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to register here in order to participate.

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0

  • Recently Browsing   0 members

    No registered users viewing this page.