Fish farms, not divers, to blame for Eilat coral damage

[Fiona]

Fish farms, not divers, to blame for Eilat coral damage

Researchers are blaming the deterioration of the once-pristine coral reefs around the Red Sea resort of Eilat on intense fish farming, and not, as previously thought, on pollution or divers.

Professor Yossi Loya* has been studying the coral reef at Eilat for the past three decades, and believes that the reef is likely to be completely wiped out unless measures are taken to stop nitrates, excreted by over 5 million farmed fish, killing the coral.

Environmentalists have long voiced concern over damage to the coral reefs close to Eilat. Positive measures such as introducing efficient sewage treatment and restricting the areas that divers could visit should have resulted in a regeneration of the reef; but in 1993, intensive fish farms began to appear in the Gulf of Eilat.

"The key point is that the Gulf of Eilat is an oligotrophic sea, a sea that does not have nitrogen at all," Professor Loya explained.
"Coral reefs thrive in seas that are poor in nitrogen. If you increase nitrogen you are changing the environment and in such a sensitive environment like coral reefs it is mainly affecting the reproductive system of corals".

From 1993 to 2000, the yield from fish farms increased from 300 tonnes per year to 2,000 tonnes - reflecting a massive increase in the number of fish being farmed, and a corresponding increase in waste products.

The fish farming industry is worth $20 million(US) to Israel. The fish farmers and scientists from state-owned Israel Oceanographic and Limnological Research Institute (which collects royalties from fish farmers) have denied that there is a link between the declining coral and the fish farms.

However, a comparison between the reef close to Eilat and those around Sharm and Hurghada - which have mass tourism, poorer sewage treatment and far larger numbers of visiting divers - illustrate that the Eilat reef has deteriorated to a much greater extent.

* Professor Yossi Loya is a professor of Marine Biology, and Chair for Environmental Research at the Department of Zoology, Tel Aviv University
Taken from Divernet

[Scuba1]

I have been diving under some fishfarms here and the seabed is dead within less than 2 years. There are some fishfarms of the coast of Callao Salvaje here on Tenerife and the university of La Laguna has estimated the waste produced by the 12 nets each having a diametre of 19 metres and each containing about 400 000 Doradas and or Lubinas is the equvalent of about 17000 people.

Makes me think.

MIchael