“More acidic ocean could spell trouble for marine life’s earliest stages”

EurekAlert!, 31st July 2008

Increasingly acidic conditions in the ocean—brought on as a direct result of rising carbon dioxide levels in the atmosphere—could spell trouble for the earliest stages of marine life, according to a new report in the August 5th issue of Current Biology, a publication of Cell Press. Levels of acidification predicted by the year 2100 could slash the fertilization success of sea urchins by an estimated 25 percent, the study shows. " If other marine species respond similarly—and there’s no evidence yet that they don’t—then we’re in trouble," said Jon Havenhand of the University of Gothenburg in Sweden. "The analogies are quite simple: we observed a 25 percent reduction in fertilization success at reduced pH, which is equivalent to a 25 percent reduction in the spawning stock of the species. Apply equivalent changes to other commercially or ecologically important species, such as lobsters, crabs, abalone, clams, mussels, or even fish, and the consequences would be far-reaching. It could be enough to "tip" an ecosystem from one state to another." However, he emphasized, more data about the response of growing acidic conditions on more species is needed before any such extrapolation can be made. Widely cited estimates show that the average level of acidity in the oceans has risen by about 25 percent in the last 150 years, since the advent of fossil fuel burning, Havenhand explained. The most recent data show that levels of ocean acidification predicted for the end of this century—about a three-fold increase over current levels—have already been measured in some coastal waters. Continue reading ““More acidic ocean could spell trouble for marine life’s earliest stages””

So long and thanks for all the fish – A roundup from the ICRS from SeaWeb

Coral Reef News – SeaWeb, July 10th 2008

So, the final, dying embers of the conference to rake over. Dick Dodge kicks things off by saying what a diverse bunch of topics we’ve covered. This symposium has been one of synthesis, he says. Here’s how we’re going to do things over the next couple of hours…

Each Mini-Symposium chair has submitted a report. Nancy Barron is going to explain more.

The goal today, she tells us, is to make this fast food… er, fun. She emailed the idea through to her “victims” and got this from Steve Palumbi. “One,” he replied. “This is an amazing thing to do. Two, this is an impossible thing to do. Since one is more important than two, let’s do it.”

SP gets up and talks about this being the coral reef Olympics. Sure is, Steve.

Oh no. They’ve each got four minutes to explain. Pity me, dear reader…

First, NB talks about how many stories from the conference have been picked up by the press elsewhere. There’s been some good stuff coming out of here. Arghh. NANCY! You’ve done it again. We’ve all got to stand up and take a bow. You won’t get a third chance.

Wow! There’s been some excellent news coverage. Well done guys. We get to listen to John Neilsen’s NPR piece. Top work, as ever. Especially as he wasn’t even here! What a star.

Now for the SuperChairs…

Continue reading “So long and thanks for all the fish – A roundup from the ICRS from SeaWeb”

2005 a deadly year for Caribbean coral

Following close on the heels of IUCN report …

PARIS (AFP, Jan 28 2008) — The Caribbean’s fragile coral reefs were devastated in 2005 by a doubly whammy of record-high temperatures and 13 full-on hurricanes, according to a UN-sponsored report released Monday.During the last 50 years many Caribbean reefs have lost up to 80 percent of their coralacp-palmata.jpg cover, damaging or destroying the main source of livelihood for hundreds of thousands of people, said the report, prepared by a team of scientists and experts at the Global Coral Reef Monitoring Network.

The study was jointly sponsored by UNESCO and the Intergovernmental Oceanographic Commission.

Coral-based ecosystems are extremely sensitive to temperature increases, which have led over the last 50 years to massive bleaching — affecting up to 95 percent of the reefs around some islands, including the Cayman Islands, Jamaica, Cuba, and the French West Indies.

2005 was the warmest year since records were first kept in 1880, and global warming is likely to increase in years to come, climate scientists have warned.

Continue reading “2005 a deadly year for Caribbean coral”

Sunscreens trigger VLPs that cause mass coral bleaching? The case of the blunt razor.

I was rung up today by a journalist who wanted me to comment on whether sunscreens could cause coral bleaching. Her question was triggered by an article published this month in Environmental health Perspectives by Danovaro, R. et al. (doi:10.1289/ehp.10966.) which shows that very small amounts of sunscreen can cause corals to bleach. This is potentially interesting given the often close association of tourists and coral reefs.Nature News

Looking closely at the paper, however, I think there may be a few problems. Whereas the article talks about ‘bleaching’ (which involves the specific movement of symbiotic dinoflagellates out of the coral tissue, which remains behind), the photo that accompanies the article shows a white coral which looks as if it has lost all of its host tissue. That is, the coral looks dead in my opinion rather than bleached.

Danovaro et al. (2008) also discuss the mechanism behind the putative bleaching caused by the sun screens. The authors saw a proliferation of viral like particles or VLPs in their ‘bleached’ specimens and concluded that the VLPs were responsible. Why did Danovaro and his team conclude this? Well, there are earlier pieces of work out of Willy Wilson’s laboartory, supposedly showing that mass coral bleaching is triggered by latent VLPs are triggered by elevated water temperatures (Lohr et al. 2007). Willy is pretty straight up about it. “I’m pretty convinced that viruses are instrumental in the whole bleaching process,” says William Wilson from the Bigelow Laboratory for Ocean Sciences Sciences in Boothbay Harbor, Maine (Nature News). Continue reading “Sunscreens trigger VLPs that cause mass coral bleaching? The case of the blunt razor.”