Hagfish Anti-Shark Slime Weapon

The hagfish found in New Zealand’s deepest waters is grotesque enough, thanks to its scary protruding teeth straight from a horror film. Now, scientists have witnessed the full power of its other gruesome feature – a built-in slime weapon to deter predators such as sharks, making it one of the planet’s ultimate survivors.

Researchers from Massey University and Te Papa have just released graphic underwater footage showing for the first time how the primitive hagfish – also known as the snot-eel – defends itself by emitting a choking, gill-clogging slime that might be the envy of any surfer under attack from a shark.

The footage, part of a study of New Zealand’s deep-sea animal diversity, is from special cameras that captured images of various fish attacking hagfish off Three Kings and Great Barrier Islands as they feed on bait attached to the camera. As soon as it is attacked, the hagfish releases a gooey mucus-like substance from its battery of slime glands and up to 200 slime pores, causing predators to gag before hastily retreating.

The video footage in New Zealand waters has proven that hagfish secrete slime at an incredibly fast speed when under attack by predators such as large sharks or bony fishes.

A paper on the findings just published online in Scientific Reports (Nature Publishing Group) titled Hagfish predatory behaviour and slime defence mechanism describes the effectiveness of the “copious slime” in choking would-be predators without apparently poisoning or killing them. This in turn allows the hagfish to carry on feeding or to make an escape, clearly a success as an evolutionary strategy.

Other new findings include the discovery that the hagfish is not only an ocean scavenger but is also a predator – with a twist. Footage reveals its bizarre method of burrowing into sand in pursuit of a red bandfish by knotting its tail for additional leverage as it grabs its hidden prey before unknotting and emerging from the sand.

Since 2009, the scientists have deployed cameras at depths ranging from 50 to 1500 metres around New Zealand. So far, over 1000 hours of footage has been collected off the Kermadec Islands, Three Kings Islands, Great Barrier Island, White Island and Kaikoura, with surveys to extend in 2012 to the sea off the Otago Peninsula and down as far as the Auckland Islands.

This research was funded by a Royal Society of New Zealand Marsden Fund Grant to Dr Roberts and Professor Anderson, a Te Papa Collection Development Grant as well as support by the Ministry of Science and Innovation via NIWA and the University of Western Australia.

Watch a video of the hagfish in action: http://www.youtube.com/watch?v=Bta18FdkVcA&feature=player_embedded

Source: Massey University

Swim Little Fishes, Swim if You Can

Fish and other sea creatures will have to travel large distances to survive climate change, international marine scientists have warned.

Sea life, particularly in the Indian Ocean, the Western and Eastern Pacific and the subarctic oceans will face growing pressures to adapt or relocate to escape extinction, according to a new study by an international team of scientists published in the journal Science.

The current research shows that species which cannot adapt to the increasingly warm waters they will encounter under climate change will have to swim farther and faster to find a new home.

Using 50 years’ data of global temperature changes since the 1960s, the researchers analysed the shifting climates and seasonal patterns on land and in the oceans to understand how this will affect life in both over the coming century.

The velocity of climate change (the geographic shifts of temperature bands over time) and the shift in seasonal temperatures for both land and sea found both measures were higher for the ocean at certain latitudes than on land, despite the fact that the oceans tend to warm more slowly than air over the land.

The findings have serious implications especially for marine biodiversity hotspots – such as the famous Coral Triangle and reefs that flourish in equatorial seas, and for life in polar seas, which will come under rising pressure from other species moving in.

Unlike land-dwelling animals, which can just move up a mountain to find a cooler place to live, a sea creature may have to migrate several hundred kilometres to find a new home where the water temperature, seasonal conditions and food supply all suit it.

Under current global warming, land animals and plants are migrating polewards at a rate of about 6 kilometres a decade – but sea creatures may have to move several times faster to keep in touch with the water temperature and conditions that best suit them.

There  are also a complex mosaic of responses globally, related to local warming and cooling. For example, analysis suggests that life in many areas in the Southern Ocean could move northward, however, as a rule, they are likely to be as great or greater in the sea than on land, as a result of its more uniform temperature distribution.

The migration is likely to be particularly pronounced among marine species living at or near the sea surface, or subsisting on marine plants and plankton that require sunlight – and less so in the deep oceans.

At the same time, sea life living close to the poles could find itself overwhelmed by marine migrants moving in from warmer regions, in search of cool water.

Future research will focus on how different ocean species respond to climate change and they are compiling a database on this for the Intergovernmental Panel on Climate Change (IPCC).

The paper “The Pace of Shifting Climate in Marine and Terrestrial Ecosystems” by Michael T. Burrows, David S. Schoeman, Lauren B. Buckley, Pippa Moore, Elvira S.Poloczanska, Keith M. Brander, Chris Brown, John F. Bruno, Carlos M. Duarte, Benjamin S. Halpern, Johnna Holding, Carrie V. Kappel, Wolfgang Kiessling, Mary I.O’Connor, John M. Pandolfi, Camille Parmesan, Franklin B. Schwing, William J. Sydeman and Anthony J. Richardson, appears in today’s issue of Science.

Source: The ARC Centre of Excellence for Coral Reef Studies