Guest essay by Eric Worrall
The Guardian claims tour operators are refusing to take people to see coral bleaching on the Great Barrier Reef, for fear it will put tourists off from visiting. My question – if coral bleaching has killed the whole reef, why bother hiding it?
Great Barrier Reef: tourism operators urge Australian government to tackle climate change
Letter calls for rapid shift to renewable energy after natural wonder affected by worst coral bleaching event yet seen.
Tourism operators have broken their silence about the worst crisis ever faced by the Great Barrier Reef, with more than 170 businesses and individuals pleading with the Australian government to take urgent action to tackle climate change and ensure the reef survives.
Many tourism operators in Queensland have previously been quiet about concerns for the reef, fearful that speaking about the mass bleaching event would turn tourists away, lowering their incomes in the short term.
The Great Barrier Reef is in the midst of the worst bleaching event ever seen, with virtually the entire reef affected. Unusually warm water has killed as much as half the corals in the northern sections and scientists have found climate change will make the those conditions normal in fewer than 20 years.
A group has now spoken out, writing to several politicians, including the prime minister, the federal environment minister and local representatives, as well as taking out an advertisement in a Queensland paper.
“Many tourism operators, they don’t want people not to come to the reef, so they’ve been reluctant to speak out” said John Rumney, who has run diving and fishing tours on the Great Barrier Reef for the past four decades.
“They are worried it will have a negative impact on the short-term cash flow. But if we don’t take care of this issue we will have no reef in the future.”
Hangon, does that mean the reef is expected to recover from this episode of bleaching?
Australia’s largest oceanic reef system, Scott Reef, is relatively isolated, sitting out in the Indian Ocean some 250 km from the remote coastline of north Western Australia (WA). Prospects for the reef looked gloomy when in 1998 it suffered catastrophic mass bleaching, losing around 80% of its coral cover. The study shows that it took just 12 years to recover.
Spanning 15 years, data collected and analysed by the researchers shows how after the 1998 mass bleaching the few remaining corals provided low numbers of recruits (new corals) for Scott Reef. On that basis recovery was projected to take decades, yet within 12 years the cover and diversity of corals had recovered to levels similar to those seen pre-bleaching.
“The initial projections for Scott Reef were not optimistic,” says Dr James Gilmour from AIMS, the lead author on the publication, “because, unlike reefs on the Great Barrier Reef, there were few if any reefs nearby capable of supplying new recruits to replenish the lost corals at Scott Reef.
“However, the few small corals that did settle at Scott Reef had excellent rates of survival and growth, whereas on many nearshore reefs high levels of algae and sediment, and poor water quality will often suppress this recovery.
What about the future? Assuming global warming occurs, what happens to reefs which are frequently subject to extreme temperatures?
We tend to associate coral reefs with tropical seas of around 28 degrees, where even slight warming can have devastating effects on corals. But in the Arabian/Persian Gulf, corals survive seawater temperatures of up to 36 degrees Celsius every summer, heat levels that would kill corals elsewhere.
In their study, the NOCS team worked closely with NYUAD researchers to select and characterise model corals from the Arabian/Persian Gulf, which will facilitate future molecular-scale investigations into why they can tolerate heat stress.
Perhaps there is a protective adaption which helps coral survive extreme temperatures?
That warning about poor water quality near coastlines, near human habitation is a concern – what could humans be doing, which might be stressing the corals of the Great Barrier Reef, causing them to become more vulnerable to warm water?
Swimmers’ Sunscreen Killing Off Coral
The sunscreen that you dutifully slather on before a swim on the beach may be protecting your body—but a new study finds that the chemicals are also killing coral reefs worldwide.
Four commonly found sunscreen ingredients can awaken dormant viruses in the symbiotic algae called zooxanthellae that live inside reef-building coral species.
The chemicals cause the viruses to replicate until their algae hosts explode, spilling viruses into the surrounding seawater, where they can infect neighboring coral communities.
Zooxanthellae provide coral with food energy through photosynthesis and contribute to the organisms’ vibrant color. Without them, the coral “bleaches” — turns white — and dies.
“The algae that live in the coral tissue and feed these animals explode or are just released by the tissue, thus leaving naked the skeleton of the coral,” said study leader Roberto Danovaro of the Polytechnic University of Marche in Italy.
The researchers estimate that 4,000 to 6,000 metric tons of sunscreen wash off swimmers annually in oceans worldwide, and that up to 10 percent of coral reefs are threatened by sunscreen-induced bleaching.
Sun cream is a big deal in Australia. Schools demand parents apply suncream to children before attending. Sky high skin cancer rates, and decades of government campaigns, ensure a high level of awareness, and a relatively high rate of suncream application – especially when bathing under the blazing tropical sunlight of the Coral Sea. Newer suncreams, spray on nanoparticle creams, as opposed to the old oily white suspension, make suncream more convenient to apply, and less damaging to clothes. Even though applying suncream likely helps to kill the coral.