Will triton snails save Australia’s Great Barrier Reef?


This video from Hawaii is about a triton snail at Lanai lookout in Oahu eating a crown of thorns starfish.

From Wildlife Extra:

Giant snail the solution to Barrier Reef’s Crown-of-thorns problem?

Beautiful as it may be, the Crown-of-thorns Starfish has had a devastating effect on parts of the Great Barrier Reef

Good news for Australia in the battle to save delicate coral organisms on the Great Barrier Reef from annihilation by the rapidly multiplying and invasive Crown-of-thorns Starfish.

Scientists have discovered that the scent of the Triton Sea Snail is repellent to the giant starfish.

The Crown-of-thorns has been responsible for 40 per cent of coral cover loss on the Great Barrier Reef in the past 30 years.

University of the Sunshine Coast senior lecturer Scott Cummins says they have learned that the Triton Snail is one of the starfish’s natural predators.

“We put [the snail] next to the Crown-of-thorns Starfish and they reacted quite obviously,” he says.

“They started to run away, which is quite an important finding because it tells us they do have very poor eyesight, so they are sensing or smelling their main predator.”

At the moment, in an effort to save the reefs, divers search for the starfish and administer a lethal injection which was developed by James Cook University, but this is very costly an labour intensive. This new discovery may provide the long-term answer to the problem.

“The snail is releasing a complex mixture of molecules,” explains Cummins. “We want to narrow it down to exactly what the molecule is then hopefully we can take that and put it into some slow release system on the reef.”

Australian Institute of Marine Science researcher Dr Mike Hall says the decline of the giant Triton Snail, prized for its beautiful shell, might have partially contributed to the population explosion in Crown-of-thorns Starfish that has had such a devastating effect.

The snail has been protected in Australia since the 1960s but it is still extremely rare on the Great Barrier Reef.

One should hope that triton snails will also help against another threat to the Great Barrier Reef: the disastrous environmental policies of Tony Abbott’s government in Australia.

Seven ways the Australian government in totally screwing up the environment: here.

Great Barrier Reef turtles released after rehabilitation


This video from Australia is called Sea turtles released near Great Barrier Reef after rehabilitation.

Daily The Guardian writes about this:

Two sea turtles have been released into the waters of Queensland’s Great Barrier Reef after being rehabilitated in captivity. One of the animals was thought to have been hit by a boat and attacked by a crocodile. Both spent time in a dedicated turtle hospital at the Reef HQ aquarium. In recent years warnings over the impact of coastal industrialisation on turtles and other animals have increased, with seabed dredging to allow the export Queensland’s natural resources of particular concern.

Great Barrier Reef let down by Australian government


This video is called BBC Great Barrier Reef II 2012 HD.

From daily The Morning Star in Britain:

Campaigners dismiss inadequate Australian Great Barrier Reef protection plan

Tuesday 16th September 2014

Environmental activists lashed out at a new Australian government plan purporting to protect the Great Barrier Reef yesterday.

The plan had been released to allay UN concerns but the activists said that it was inadequate to halt the reef’s decline.

Environment Minister Greg Hunt claimed that the draft “Reef 2050 Long-Term Sustainability Plan” was an effort to balance important priorities.

“Maintaining and protecting this iconic World Heritage area, while considering the needs for long-term sustainable development, is a critical priority,” Mr Hunt alleged.

But WWF Australia head Dermot O’Gorman said the draft did not set high enough targets for cutting agricultural pollution or provide “the billions of dollars required to restore the health of the reef.”

“At this stage, Reef 2050 lacks the bold new actions needed in order to halt the reef’s decline,” Mr O’Gorman said.

The draft plan bans future port development in the Fitzroy Delta, Keppel Bay and North Curtis Island near Rockhampton in Queensland state — areas of the reef described by environmentalists as key incubators of marine life — but it exempts priority port development areas from the ban.

Australian Marine Conservation Society spokeswoman Felicity Wishart said it should have recommended laws to minimise dredging as well as ban dumping in reef waters.

“From our point of view the reef is in dire straits,” she said, adding that the plan should have been a “lifeline” to turn the reef around over the next 35 years.

Australia’s Queensland state government is jeopardising The Great Barrier Reef with its decision to push ahead with damaging legislation, WWF-Australia warns: here.

Lionfish hunt together, share food equally


This video is called Zebra Lionfish (Dendrochirus zebra).

From New Scientist:

Zoologger: The fish that kill with special-ops signals

25 June 2014 by Michael Slezak

Species: Dendrochirus zebra

Habitat: Hanging out in the Great Barrier Reef and Indonesia; waging war in Caribbean reefs

It is night-time on the reef. With its Fu Manchu moustache and weed-like fins a lionfish blends into the swaying seaweed.

Spotting a school of little fish swimming slowly through the coral, the lionfish quickly scans around for hungry accomplices. Swimming to them one-by-one it gives a quick wiggle of its tail fin and then a slow undulating wave of its pectoral fins. The accomplices respond with a simple wave of their pectoral fins. The hunt is on.

Together the gang approach the fish, which don’t seem to see the lionfish even from up close. Using their fan-like fins they herd the prey into a corner before taking it in turns to dart into the school, each time swallowing their meal whole. Their bellies full, the conspirators part ways into the tropical night.

Invisible fish

Lionfish are venemous, and have few natural predators. They are also so adept at camouflage that Oona Lönnstedt at James Cook University in Townsville, Australia, and colleagues recently showed that they seem to be invisible to their prey. In fact, when hunting alone, they convince their prey to swim into their mouths by blowing a stream of water towards them.

But it turns out that they have another trick up their sleeves: very good communication skills.

Studying lionfish both in the lab and on the Great Barrier Reef, Lönnstedt and colleagues found that the fish sometimes conducted a distinctive fin display. Whenever there was another lionfish nearby, the fish that spotted the prey used this signal and up to four other lionfish responded and joined in the hunt.

The signal was only seen prior to a group hunt, which suggests it is a method of communication – a kind of special operations signalling with their fins. “As an intentional signal, it’s very rare. It implies that there’s a complex cognitive ability in fish,” Lönnstedt says.

All fish are equal

Lönnstedt also found that group hunts were more fruitful than solo efforts. The lionfish also shared the food completely evenly. “That blew our minds,” she says. “That’s the first time that’s been proven in animals. Usually lions or hyenas will catch prey and share it hierarchically. The top animal takes the lion’s share, so to speak.”

Group foraging and hunting have been seen in all sorts of animals, from chimpanzees to bees and eels. But very little has been done into how it is triggered, says Amanda Ridley from the University in Western Australia in Perth. “We have scores of papers about cooperation, but we don’t know how they do it,” she says. “This paper has nicely encapsulated the fin display. It goes to the other and says ‘hey how about it, let’s go fish together’.”

Journal reference: Biology Letters, DOI: 10.1098/rsbl.2014.0281

Correction, 26 June 2014: When this article was first published, we mistakenly described Dendrochirus zebra as an invasive species.

See also here. And here.