Tiger Sharks in Hawaii - Paper!

Click for detail!

And I cite.

Although tiger sharks clearly utilize open-ocean habitats in both Atlantic and Pacific oceans, the majority (78.7%) of satellite location estimates for tiger sharks captured around Maui and Oahu during the present study were in coastal waters over insular shelf habitat.

Tiger shark affinity for coastal waters and shelf habitats has been documented in previous studies in Hawaii, Australia, the Galapagos, the Bahamas and Florida, although movements are generally much wider-ranging over the extensive continental shelf areas off Australia and Florida, than over the smaller insular shelf habitats surrounding the oceanic islands of Hawaii or the Galapagos.
Conversely, most tiger sharks tagged at Challenger Bank (Bermuda, Atlantic Ocean) predominantly used open-ocean habitat.

These apparently conflicting patterns of open-ocean versus coastal habitat use by tiger sharks may partly stem from the demographic characteristics of sharks tagged in these different studies.
For example, eighteen (95%) of 19 highly-migratory tiger sharks tagged at Challenger Bank were mature males, whereas tiger sharks tagged during the current and previous Hawaii studies were mainly (59–80%) mature females which predominantly utilized coastal habitats, and tiger sharks exhibiting high coastal residency in the Galapagos were predominantly (85%) sub-adult females and males.

These differences in habitat use are consistent with habitat segregation among different life history stages, with sub-adults of both sexes and mature females occupying coastal areas, and mature males occupying offshore habitats, but likely also reflect the species ability to adapt the scale and pattern of movements to local resource distribution.

Very interesting!
Once again, Hawaii's Shark Research Team has produced a stellar paper focusing on the residency pattern of Tiger Sharks between Kauai and Maui.

Dunno about you - but I just love love love this stuff.
Step by step, all that initially rather baffling local, regional and global  sneaking around is being deciphered, and I'm just totally fascinated by the insights.

Enjoy the new paper - required reading!

Gallivanting Tiger Sharks - new Paper!

Remember this post?

Sure you do! :)

Now, check this out.

Once again, this is evidence for the massive influence of environmental factors whereby both the coastal abundance and swimming performance of those migrating Tiger Sharks are being shown to be highest at ~22°C. Consequently, they track their optimal temperature and are thus more likely to be found in coastal areas in winter in the tropics; but towards temperate latitudes, they are more likely to be found in coastal areas in summer, see the figure at the top - and as climate change continues to heat up the oceans, those tracks are likely to shift poleward with according potential consequences for coastal communities, see the example of Sydney.

Very interesting!

Incidentally, this is very similar to what we are currently experiencing with our Bulls who have been shown to favor a temperature of ~26°C.
As the water temperature at Shark Reef has recently hovered around 29°C for a protracted period of time,  the number of especially the larger Bull Sharks has been appreciably lower - and whereas we don't dispose of any strong evidence, it is only fair to speculate that they may have retreated to greater depths or even absconded to places like Kadavu where the water temperature has been significantly lowered by Gita.

But I'm digressing as usual.

Great paper featuring numerous people I like and respect.
Enjoy!

 

Maui Tiger Shark Paper - fucking Brilliant!

Source.

Wow - you must really read this paper.

Stories here and here, tracks here.

And here's even a bunch of video clips for the lazier ones among you - from exhaustive to easy all the way to basic. I must say, this is all very impressive indeed.

Epic stuff - enjoy!

Sharks filming Sharks!

Source.

 

This is simply awesome!

Stories here, here and here.

Who would have thought that those different species coexist so peacefully!

 

Enjoy!

No smoking Gun!

George and Collier, eat your heart out!
This is how you do it!

Great piece!

Kudos, again, to Carl Meyer and also to his mentor Kim Holland, the Big Silverback at the Hawaiian Shark Lab!

Carl Meyer - thank you!

Carl Meyer and Yannis Papastamatiou from the University of Hawaii at Manoa. Source.

This is as good as it gets.

Another issue which has generated a lot of heat here in Hawaii and elsewhere is shark cage diving ecotourism. 

These activities have proven hugely controversial. 

We’ve done a fair bit of work on the one here on Oahu, including a meta analysis of logbook data and tracking long-term movements of sharks captured at the cage diving sites -

the takeaway message is that there’s absolutely no scientific evidence whatsoever that the existing operations off Oahu are a threat to public safety, which has been people’s major concern.

Full interview here.

It's a great read that touches on many sometimes controversial topics and is garnished with many useful links - much too exhaustive and also, much to good to be synthesized in an abbreviated synopsis.

Once again - required reading!

Enjoy!