Caribbean lionfish invasion

Posted on July 7, 2009 by ovehblog

A new Reef Site in Coral Reefs (Green and Cote 2009) describes the striking densities of non-native lionfish on coral reefs in the Bahamas. Lionfish (Pterois volitans), a predator from the central and western Pacific ocean, were first sighted in 1992 off Florida and have been spreading rapidly throughout the Caribbean (USGS Nonindigenous Aquatic Species Database 2009).

Lionfish in the Bahamas. Photo credit Richard Carey

On deep offshore reefs off of North Carolina, they are now the second most abundant fish (Whitfield et al. 2007).

Mean lionfish and grouper abundances from 17 sites off NC, USA. (from Whitfield et al 2007).

From Green and Cote (2009): At three sites, each separated by more than 1 km, we found >390 lionfish per hectare (mean ± 1 SD; 393.3 ± 144.4 lionfish ha−1, n = 4 transects per site). These densities are more than 18 times higher than those reported by Whitfield et al. (2007) from invaded habitats off the coast of North Carolina, USA (21.2 ± 5.1 ha−1)… Caribbean sightings have now been confirmed as far west as Cuba and the Cayman Islands and southeast to St. Croix.

[youtube=http://www.youtube.com/watch?v=Ar0CX8dj948&w=425&h=344]

“One-ton manta cyclonic feeding frenzy”

Posted on July 5, 2009 by ovehblog

Go check out these incredible photographs by National Geographic photographer Thomas Peschak of mantaray feeding frenzies in the Maldives. Apparently this swirling ‘cyclone‘ feeding behavior is rarely seen outside of the Maldives. Click here for a previous post on Climate Shifts for more details and video footage of Mantaray feeding behaviors.

Sylvie Earle – living legend and hero for the planet

Posted on July 3, 2009 by ovehblog

http://video.ted.com/assets/player/swf/EmbedPlayer.swf

TED, a nonprofit devoted to ‘Ideas Worth Spreading’ hosts an annual conference bringing together ‘world’s most fascinating thinkers and doers, who are challenged to give the talk of their lives’. I’ve watched quite a few incredible talks (Al Gore, Tierney Thys, & Jane Poynter to name but a few), but the one that stood out for me was the incredible Sylvia Earle, who is due to host a seminar on marine ecology and conservation in Brisbane in August (link). See below for her bio from the TED website:

Why you should listen to her:

Sylvia Earle, called “Her Deepness” by the New Yorker and the New York Times, “Living Legend” by the Library of Congress and “Hero for the Planet” by Time, is an oceanographer, explorer, author and lecturer with a deep commitment to research through personal exploration.

Earle’s work has been at the frontier of deep ocean exploration for four decades. Earle has led more than 50 expeditions worldwide involving more than 6,000 hours underwater. As captain of the first all-female team to live underwater, she and her fellow scientists received a ticker-tape parade and White House reception upon their return to the surface. In 1979, Sylvia Earle walked untethered on the sea floor at a lower depth than any other woman before or since. In the 1980s she started the companies Deep Ocean Engineering and Deep Ocean Technologies with engineer Graham Hawkes to design and build undersea vehicles that allow scientists to work at previously inaccessible depths. In the early 1990s, Dr. Earle served as Chief Scientist of the National Oceanographic and Atmospheric Administration. At present she is explorer-in-residence at the National Geographic Society.

Sylvia Earle is a dedicated advocate for the world’s oceans and the creatures that live in them. Her voice speaks with wonder and amazement at the glory of the oceans and with urgency to awaken the public from its ignorance about the role the oceans plays in all of our lives and the importance of maintaining their health.

“We’ve got to somehow stabilize our connection to nature so that in 50 years from now, 500 years, 5,000 years from now there will still be a wild system and respect for what it takes to sustain us.” – Sylvia Earle

Endangered shark found. Eaten.

Posted on May 19, 2009 by ovehblog

megamouth2

The megamouth shark (Megachasma pelagios) is one of the worlds rarest sharks – spotted only 43 times since its discovery back in 1976 off Oahu, Hawaii. These sharks are huge and bizzare creatures, capable of growing upwards of 5m in length, with luminescent light organs surrounding the mouth to attract plankton and small fish. So rare is the megamouth shark, that apparently scientists were surprised to find the 44th megamouth shark (caught by mackeral fishers in the Phillipines) had been cooked and eaten by local villagers before anyone could take a closer look. I wonder which part of the 500 kilogram shark was considered the delicacy? Read more at the National Geographic – thanks to Brian for the tip!

Raising awareness of coral reefs through the art of crochet

Posted on January 26, 2009 by ovehblog

reef1

A fluff piece in more ways than one! The Institute For Figuring have been developing the ‘hyperbolic crochet coral reef’, a collective of crochet coral reef organisms knitted by hundreds of people across the globe. By altering the style of crochet through differing algorithms, the crochet reef has ‘evolved‘ an impressive diversity of reef associated organisms. The crochet reef has been shown at exhibitions across the US, and carries with it a serious message:

As part of the Crochet Coral Reef project the IFF has constructed a Bleached Reef, a handicrafted invocation of what happens to coral reefs under environmental stress. Most of the forms in this reef are crocheted from varying shades of white and cream, mimicking the effect of actual coral bleaching. Corals acquire their colors from microscopic zooaxanthellae that live within the polyps – these symbiotic organisms help the polyps feed. When corals get stressed by environmental toxins, or by rising water temperatures, the polyps expel the micro-organisms, leading to the washed out look known as “bleaching.” Polyps can survive for a short time in the absence of zooaxanthellae, but not over the long term. A healthy reef ecology is a co-operative one and in the long term the corals need the microorganisms to survive. Over the past decade reefs around the world have been subject to an increasing number of major bleaching events, suggesting that rising water temperatures are taking a heavy toll.

More from The Guardian and the New York Times, or click here for more photographs from Flickr.

Harbor seal debunks AGW myth

Posted on January 6, 2009 by ovehblog

A harbor seal, presumably from the north Atlantic, showed up in Bermuda this week and effectively debunked the global conspiracy known as AGW (Anthropogenic Global Warming). William Weaver of the group Americans for Climate Truth said in a statement “scientists have reported that thousands of species were moving away from the equator, but this sighting is proof that animals are now moving towards the equator to escape the current global cooling“. Weaver added, “this discovery overturns that IPCC “report” and the thousands of “scientific studies” that formerly supported the AGW hypothesis”.

Joel Swathmore of Save The Humans, issued a press release stating “this news comes on top of the fact that it got really freaking cold in my town a few weeks ago. Both pieces of evidence clearly indicate we are heading into an ice age. Saint Gore was wrong – the big worry now is how to keep the earth from freezing over. ”

Update (07/01/08): it appears that Michael Duvinak over at the Skeptics Global Warming blog doesn’t have much of a sense of humour… J. Roff

Update II (07/01/08): OK, if it isn’t obvious, THIS IS A JOKE (although the seal story is real). But I do think sarcasm is one way we can begin to point out the foolishness of some of the skeptic arguments. And it isn’t uncommon to see believers of AGW make similarly dopey arguments, essentially confusing weather with climate. “dude, what about that heat wave – must be global warming!”

Manta rays

Posted on January 5, 2009 by ovehblog

http://vimeo.com/moogaloop.swf?clip_id=2718705&server=vimeo.com&show_title=1&show_byline=1&show_portrait=0&color=&fullscreen=1

2008 was the year that scientists realised that the humble manta ray (Manta birostris) might not be a a solitary species as initially thought. First described by the naturalist Johann Julius Walbaum back in 1792, the manta ray grows in excess of 7.6m (>25ft) and weighs up to 2300kg (~5,000lbs) – about 4/5ths of the weight of a Hummer SUV.

Andrea Marshall, a PhD student at the University of Queensland has been studying the ecology of manta rays in Mozambique for over 5 years, and his since identified over 900 individuals. Using genetic and morphological markers, her research showed that there are at least two different species of manta ray: the smaller common manta ray (as in the above video clip) specific to coastlines and coral reefs around the globe, and a second larger species of manta ray that is more elusive, and has broad migratory habits.

As Andrea points out, manta populations are frequently small in size, and intense fishing pressure can threaten the stability of local populations in a few years. The more common manta ray is particularly susceptible to unsustainable localised fishing pressures due to their restricted migratory ranges, whilst the larger migratory species causes problems with population estimates and conservation management to it’s broad home range. Manta rays are in increasing danger from the effects of fishing, and cartilidge and branchial plates (the characteristic mandibles or ‘lobes’ that protrude from the mouth) are sold for upto $50USD per kilo in Asia.

I filmed the video at the top whilst on fieldwork in the central Great Barrier Reef last year. The two manta rays (the smaller ‘common’ type) were feeding on an upwelling of plankton off the edge of the reef crest, and were happy for us to swim between them without being disturbed. Visit the homepage of the the Manta Ray & Whale Shark Research Centre in Mozambique to read more about the conservation and protection of these amazing creatures, or check out their blog (“The latest news on the biggest fishes“) over at wordpress

People must be part of reef conservation

Posted on December 15, 2008 by ovehblog

This is from a July 10 (2008) press release from the ARC Centre of Excellence for Coral Reef Studies. I think this and Terry’s plenary did a great job of covering the importance of people in the equation. You can watch Terry Hughes’ plenary talk here.

terry-hughes

The world’s coral reefs are not doomed – provided governments and communities take the urgent and necessary actions to preserve them.

That’s the message from eminent Australian marine scientist and recipient of this year’s Darwin Medal Professor Terry Hughes in his keynote address to the 11th International Coral Reef Symposium, being held at Fort Lauderdale, Florida, USA from June 7-11.

Prof. Hughes is the Director of the Australian Research Council Centre of Excellence for Coral Reef Studies, based at James Cook University, Townsville, Australia.

“The global coral reef crisis is really a crisis of governance. Many of the measures put in place are failing, not because of biology, but because of lack of support from local people and governments,” he says.

“For example many no-take marine reserves have been set up round the world by non-government organisations – but nearly all of them are proving unsuccessful because they ignore the needs of the local population and have failed to win their backing.”

Professor Hughes called on coral reef researchers worldwide to work harder at the societal and economic aspects of protecting the oceans and their living resources. Good biology alone is not enough. “The reefs are not doomed if we all do the right thing,” he asserts.

Continue reading →

National Geographic photographs southern right whales

Posted on November 7, 2008 by ovehblog

Amongst the winners of the National Geographic “best wild animal photos of 2008” (link) is this incredible photograph of a diver and a southern right whale, taken in New Zealand. Like most whale populations, the souther right whale was extensively hunted from the mid 18th century up until the early 1970’s, severely depleting the southern Pacific populations around the New Zealand coastal waters . Since the ‘official’ worldwide ban on hunting right whales in 1937, southern right whales began to appear off the coast of New Zealand from the early 1960’s onwards. See the full set of photographs by Brian Skerry over at the National Geographic website (Link)

“One third of coral species face extinction”

Posted on July 14, 2008 by ovehblog

The Telegraph, 10th July

One third of the major reef-building coral species are vulnerable to extinction, and the pace of destruction is increasing so it is conceivable that the "rainforests of the ocean" could be wiped out this century.

The warning that coral communities are faring even worse than their terrestrial counterparts, notably tropical rainforests, is given by an international team led by Prof Kent Carpenter, Director of the Global Marine Species Assessment Of Conservation International And The International Union For Conservation Of Nature, IUCN.

Built over millions of years, coral reefs are home to more than 25 percent of marine species, making them the most biologically diverse of marine ecosystems.

The loss of reefs could have huge economic effects on food security for around 500 million people who are dependent on reef fish for food and/or their livelihoods and tourism is also likely to suffer.

"The results of this study are very disconcerting," said Prof Carpenter, lead author of the Science article.

"When corals die off, so do the other plants and animals that depend on coral reefs for food and shelter, and this can lead to the collapse of entire ecosystems."
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"Whether corals actually go extinct this century will depend on the continued severity of climate change, extent of other environmental disturbances, and the ability of corals to adapt," the article concludes.

"Our results emphasize the widespread plight of coral reefs and the urgent need to enact conservation measures."