Saturday 14 June 2008

Manta Diving At Its Best

12/1/08

We dropped in on Manta reef hoping for a good day. But it was more than good, it was special. We saw the first Manta after about 5 mins, I just caught a glimpse of the wing tip as it cruised along the top if the reef. As we made our way along the reef another manta came past us, another monster at just under 4m, but white underneath with “go fatser” stripes on top. They disappeared, then minutes later they both came back into view with another smaller black one behind. 3 mantas flying in formation. That’s what I’m talking about!

As we got to the end of the reef and turned around, two of them came directly towards us and, as we watched them turn back the other way, the third came from behind and no-one knew where to look. We headed back and I remember thinking, “that was a bit special”. But that was just the beginning.

After a few minutes we bumped into Joe’s group and he signalled that one was barrel rolling, so we went to check it out. We were met with the 4m black manta barrel-rolling about 3m away from us. He moved along a bit and suddenly the dive went crazy. Joe was pointing up at a 4th small white manta barrel rolling above us and the other 3 big ones were putting on the most amazing arial display I’ve ever seen.

The RAF Red Arrows haven’t got shit on these guys. We were surrounded by 3 enormous mantas rolling over and over and a smaller one going crazy above our heads. Diving does not get any better!

Friday 13 June 2008

Scuba Diving Fiji: FIHTA Dive Fiji EXPO 2008 pics

Some photos from the recent Dive Fiji EXPO.

Scuba Diving Fiji: FIHTA Dive Fiji EXPO 2008 pics

Thursday 12 June 2008

Extreme Sport Snorkelling Aboard Bite Me

Now and again, the hard working Directors of Matava Resort get the chance to take a day off and go play with toys normally reserved for guest activities. Sometimes we go explore diving along the mile upon mile of outer slopes of the Great Astrolabe Barrier Reef. Sometimes we go heavy tackle marlin fishing or chase a National or World line class gamefish Record.

Sometimes we just do something crazy.

In March we elected to do someithing nutty and geared up Bite Me with medium to heavy tackle, deep drop jig rods, underwater camera - and snorkeling gear.

About an hour and a half offshore from the resort is a seamount that rises from depths of about 9,000ft to a shallow peak at 400ft. Its a very fishy place to go and Bite Me often fishes there for marlin, yellowfin, wahoo and mahi mahi. We also find sharks there, much to the distress of livebaits set for marlin and it is normal to see the occasional hammerhead, tiger or oceanic white tip cruising around. The largest shark we have ever seen aboard Bite Me was a huge tiger shark out on the seamount that followed a hooked fish right up to the transom.

On arrival, we drifted gently over the seamount with a freshly caught yellowfin tuna head on the end of a rope off the back. We then dropped a deep drop jig rod to the sea floor with a couple of small hooks baited with fresh yellowfin tuna . In no time we were bringing up a big fat large eyed bream. Delicious to eat but this fish was meant for something else. We brought it up to just below the surface and then waited for its distressed actions to call in the nearest shark. Cameraman Richard and his 'watch my back' man Stuart geared up.

After about a minute I spotted a shark coming in and gave the signal for the baits to be pulled in and the snorkelers to enter the water. Stuart dipped his head in to check the sharks species and behavior and then off they went.

This shark was cautious and circled the snorkelers in a wary fashion before cruising off into the depths. Richard fired off some amazing photographs and we are now in the process of asking several shark experts to help us identify her. So far our research indicates a species of oceanic whaler but her unusually thick caudal penduncal (tail wrist) and keel is causing some debate.

Whatever she was, she was majestic and a thrill to swim with in open water.

Personally, I prefer to keep my feet high and dry on the bridge....

Which Pelican Case is Best for You?

Backscatter

Which Pelican Case is Best for You?

By Sy Harris


From L to R, Top to Bottom; Pelican 1520, 1560, 1510, 1610, 1620

Protecting your gear with a solid carrying case is tantamount to keeping your gear in perfect condition. When buying a case size, weight and flexibility must come into consideration. Remember, your case will not only protect your system, it will be luggage as well. You want to select a case that will expand with your system, but not be so large that it goes over the airline’s weight restrictions. Other considerations would be whether it rolls or can be considered carry-on luggage, or if the case has Velcro cushioning or pick and pluck foam. Velcro is flexible and all of our generic cases come standard with it, but when buying a video system, companies such as Light and Motion offer their packages in Pelican cases with customized foam. Below are the Pelican cases we recommend."

Read the article here: Which Pelican Case is Best for You?

Sunday 8 June 2008

Creature clones itself to avoid becoming fish food

  • 18:00 13 March 2008
  • NewScientist.com news service
  • Catherine Brahic
Bottom-dwelling sand dollars are related to sea urchins and sea stars (Image: GNU licence)
Bottom-dwelling sand dollars are related to sea urchins and sea stars (Image: GNU licence)
Cloned larvae (right) are smaller than non-cloned larvae (scale bar: 0.2 mm) (Image: Dawn Vaughn)
Cloned larvae (right) are smaller than non-cloned larvae (scale bar: 0.2 mm) (Image: Dawn Vaughn)

It's a novel escape route that makes a mockery of the status of the individual: if you run the risk of being eaten, just clone yourself. That is the approach taken by the larvae of sand dollars – marine animals related to sea urchins.

Fish are voracious predators of sand dollar larvae. Dawn Vaughn and Richard Strathmann of the University of Washington, Seattle, found that when they put four-day-old sand dollar larvae in a tank with fish mucus, the larvae cloned themselves.

They did this by either splitting in two or by producing a small bud which detached itself and developed into a new larva. Either way, the clones were smaller than the original larvae. Sand dollars did not clone themselves if there was no fish mucus in the water.

Vaughn and Strathmann believe the larvae sense the mucus, interpret it as a sign that fish are nearby, and respond by producing clones.

Better odds

There is no parental care in this species. "[The mother] is on the seafloor," says Vaughn. "She has no idea what types of risk her offspring are going to meet, so the larvae respond to cues from predators."

Cloning gives the larvae's genes a greater chance of survival in two ways. With two copies around one is statistically more likely to escape predation. Also, the smaller clones are less likely to be detected by predators.

"Studies indicated there is an optimal size below which fish do not detect their prey," says James McClintock, an ecologist at the University of Alabama at Birmingham, US, who studies how "things that can't run away from predators defend themselves".

Cloning does have a cost, however. Vaughn and Strathmann found that cloned larvae developed into smaller sand dollars: just before metamorphosing into adults, the clones were on average one-third the volume of non-cloned individuals.

Unique response

This could make it more difficult for clones to survive as adults, which only reproduce sexually, but suggests that overall, the benefits outweigh the risks.

Cloning has been seen before in echinoderms – a group of marine organisms that have a five-axis symmetry, including brittle stars, sea stars and sea urchins, and sand dollars. But in all cases, it has been in response to conditions that are favourable for growth, such as plentiful food or favourable temperatures.

"This is the first demonstration that cloning can be induced by predation," says McClintock. "What is so unique in Vaughn's study is that this defence becomes a reproductive response – making more of yourself in anticipation of risk."

While this is the first demonstration in nature, cloning as a response to predation is common in science fiction – it's how Cylons in the TV show Battlestar Galactica, for example, cheat death.

Journal reference: Science (vol. 319 p. 1503)