Satellite Tracking of Manta Rays Highlights Challenges to Their Conservation

We just finished reading an amazing paper on Manta birostris (thanks Gabriel Fava) written by Rachel T. Graham, Matthew J. Witt, Dan W. Castellanos, Francisco Remolina, Sara Maxwell, Brendan J. Godley, Lucy A. Hawkes.

For fans of in depth research data on very cool critters this is as good as it gets.

Manta gill rakers are another in a series of culinary and medicinal treats sent to Asia and the market is growing putting pressure on these magnificent animals.

Abstract

We describe the real-time movements of the last of the marine mega-vertebrate taxa to be satellite tracked – the giant manta ray (or devil fish, Manta birostris), the world’s largest ray at over 6 m disc width. Almost nothing is known about manta ray movements and their environmental preferences, making them one of the least understood of the marine megavertebrates.

Red listed by the International Union for the Conservation of Nature as ‘Vulnerable’ to extinction, manta rays are known to be subject to direct and incidental capture and some populations are declining. Satellite-tracked manta rays associated with seasonal upwelling events and thermal fronts off the Yucatan peninsula, Mexico, and made short-range shuttling movements, foraging along and between them. The majority of locations were received from waters shallower than 50 m deep, representing thermally dynamic and productive waters. 

Manta rays remained in the Mexican Exclusive Economic Zone for the duration of tracking but only 12% of tracking locations were received from within Marine Protected Areas (MPAs). Our results on the spatio-temporal distribution of these enigmatic rays highlight opportunities and challenges
to management efforts.

Complete paper here.

How to interact with white sharks - California

No screaming, no panic, no fear. This is Homo Sapien and a tagged Carcharodon carcharias meeting in the open ocean off the coast of California this week.

Kudos to Grind TV for the story and to Chuck Patterson for a once in a lifetime moment with whites that showed the world how interacting with these wonderful critters can be done without the hype:

Me my Shark and I from Chuck Patterson on Vimeo.

Dive Nin-Ja!

O.K, you're probably wondering why in Neptunes Great Sea we would ever feature a T-shirt company here at Underwater Thrills: Diving With Sharks.

They're cool, we said it first. If you're not sporting a Dive Ninja T after your next shark encounter you ain't no kind of diver. And do not let the the £20 price tag sway you from owning a piece of dive history.

When you do buy one, and you will, tell 'em, Shark Diver sent you.

Molokai Shark at 3300'

Score one for for the science guys this week. A video surfaced of one of our all time favorite underwater "denzines of the deep" the Six Gill Shark.

What makes this critter interesting is it's ability to flourish in water temps hovering in the 40's and less, and at a depth of over 5000'. This one was filmed at 3300' and with his 18 foot profile we were not surprised to hear the normally laid back deep water guys saying "Holy Crap!".

Great White Sharks at 100 Feet Rottnest Island

Score one for the science guys in Australia. A small team of dedicated researchers have been placing unmanned video cams down at 100 feet with some bait to see what's there. Beats paying some grad students to do the same job.

Since this is Australia to no ones great surprise a 10 foot Great White showed up and did a fly by completely caught on tape. Naturally the local news media has gone all "caddy-wompus" on this story.

Rottnest Island is just a few miles off of Perth.

Last we heard White Sharks were coming out of the tap water in Perth, but they are screaming about this video all the same.

Anytime you can get a Great White on tape we call that a good day. Of course it would be nice if they could have framed up this video a bit better and maybe tracked the shark a bit. Looks like the guys from Shark Diver will have to pack a few cages and go investigate.

Click here for the complete story and video.

Now, about the name of this island?

Great White Shark-Geek Tech

The good folks at Shark Tech have created the ultimate geek divers dream. The "Shark Shooter".

O.K, it's not called the "Shark Shooter"-but it might as well be called that. What you are looking at is the latest advance in diver tech. Now a lot of you old school underwater shooters will say "this is a scuba abomination, be gone from our web browsers!".

Ye, of little faith. Remember the great underwater war between film and digital shooters, now who's laughing?

For those of you out there who like to shoot sharks, this mask-6 gig camera combo allows you to be hands free, so you can hold a big fish carcass and bring the sharks in even closer.

As Britney Spears would say-Cool Ya'll!

Unfortunately these masks only come in classic yum-yum yellow, but heck, with that fish carcass in your hands perhaps the 16 foot Tiger shark you just chummed in will not notice.

Geek on Diverman!