Our coral reefs are dying

My newest book, Disease-Hunting Scientist, has been officially released.

My newest book, Disease-Hunting Scientist, has been officially released.

This week I’m giving you a column-sized version of another of the lengthy chapters devoted to individual scientists in the book.

Laurie Richardson, professor of Biology at Florida International University in Miami, is researching black-band disease in coral reefs — which means she spends a lot of each summer scuba-diving, often for hours a day.

At 287,231 square kilometers, coral reefs are less than a 10th of a per cent of the total ocean floor.

But they support more than a million species of marine life.

They are also dying, from pollution, overfishing and black-band disease, among others.

Richardson started her career researching “microbial mats,” communities of microbes that live in the sulfur-rich water of hot springs.

She then worked in Wisconsin on a NASA project that used satellite data in the study of aquatic ecosystems. That led to three years at NASA’s Ames Research Centre in California learning remote sensing and image processing, which in turn landed her in Florida with a NASA-funded grant to work on algal pigments and remote sensing.

One day, while she was diving for fun on a coral reef, somebody showed her an example of black-band disease-and she immediately recognized it as similar to the microbial communities she’d studied in hot-spring outflows.

She looked in the scientific literature, none of which had made that connection. And that was how the research she’s now been doing for more than 15 years began.

Like most scientists, Richardson spends most of her time writing papers and proposals, teaching or in her laboratory, but about 10 per cent of the time, mostly in the summer, you can find her diving with graduate students, undergraduate students and research collaborators, collecting samples and monitoring the progress of disease on the reef.Coral samples are taken with numbered, sterilized syringes. The divers record on underwater slates the number of the syringe, what the sample is, and a description of the diseased coral.

Evenings of the 10-day-long diving expeditions are typically spent transcribing information from the underwater slates into a database or field notebook. Most of the time the diving itself is fun. But not always. On one occasion, Richardson suffered the bends (an extremely painful condition caused by bubbles of dissolved nitrogen forming in the bloodstream as the diver surfaces).

On another, a sudden strong underwater surge reduced visibility to nothing and threatened to sweep her and her students away from the boat into the Gulf Stream. Corals consist of an extremely thin layer of living tissue (often less than a millimeter thick) over a rock-like skeleton of calcium carbonate. A lot of bacteria live in association with the coral’s surface and can cause a really nasty infection in any cut. Fortunately, Richardson has avoided that particular hazard so far.

As for black-band disease, Richardson says it’s now like a jigsaw puzzle that is maybe seven-eighths of the way filled in.

“Anything we figure out now is one more piece of the puzzle, so that is really exciting.”

She’s figured out as the disease-causing community of bacteria (dominated by blue-green algae) first grows, it consumes the available oxygen, opening the door for another group of bacteria that thrive in an oxygen-free environment, instead using sulfate dissolved in the water. Those bacteria produce sulfide gas as waste, killing coral tissue, which is then devoured by additional bacteria.

Contributing to the problem: a warming ocean. Corals like warm water, but not too warm. For microorganisms, on the other hand, the warmer, the better. As a result, the growth of bacteria and blue-green algae “takes off like a rocket” at the same time that the corals they are living on become stressed. The result is disease.

Richardson’s work may also shed light on human diseases, because many human diseases are also caused by a community of bacteria. In fact, her current funding is from the National Institutes of Health.

And finally, it’s a wonderful teaching model.“I’m a biology professor, and my students are learning all about ecology and physiology and microbiology and molecular genetics while they’re out there in this incredible environment working on the reef.”

Edward Willett is a Regina freelance writer. E-mail comments or questions to ewillett@sasktel.net. Visit Ed on the web at www.edwardwillett.com.

Just Posted

Rural transit service rolled out

2A South Regional Transit will link Innisfail and Penhold with Red Deer

Some Red Deer waste collection schedules change due to holiday season

Tuesday collections will be moved for two weeks

Red Deer ‘champion’ helps hospital by sharing ongoing petition

It’s been about three years since many physicians at Red Deer Regional… Continue reading

Red Deer Airport’s prospects are looking up for 2019

Ultra-low-cost passenger service is on the horizon

Funding down for Red Deer Christmas charities

Food hampers and toys for children going out to those in need

Alberta’s Sundial starts shipping to AGLC this week

Sundial’s Rocky View facility has received the green light from Health Canada… Continue reading

Penny Marshall dead at 75, best known as TV’s Laverne and director of ‘Big,’ ‘A League of Their Own’

Bronx-born Penny Marshall, who found ’70s sitcom success on “Laverne and Shirley”… Continue reading

Chabot scores overtime winner to lift Senators over Predators 4-3

OTTAWA — Thomas Chabot saw an opening and he took it. And… Continue reading

Canadian Marielle Thompson earns World Cup ski cross bronze in season opener

AROSA, Switzerland — Canada’s Marielle Thompson captured bronze at the opening World… Continue reading

Canada doesn’t make Oscars short list for best foreign language film

LOS ANGELES — Canada is no longer in the running for best… Continue reading

Warrant issued for arrest of ‘Schwimmer lookalike’ suspect

LONDON — A British judge has issued an arrest warrant for an… Continue reading

Moneywise: Canadian workers unhappy with pay, want pension plans

Many working Canadians are feeling underpaid and are so worried about their… Continue reading

Brazil police say faith healer has turned himself in

RIO DE JANEIRO — A celebrity faith healer accused of sexually abusing… Continue reading

B.C. hockey coach creates ‘gear library’ to remove cost barrier of sport

VANCOUVER — Nicola Froese says she has always loved playing sports, but… Continue reading

Most Read