Agricultural Pesticides Threatening Great Barrier Reef

A new water quality survey conducted by the Australian government shows that agricultural pesticides are harming the Great Barrier Reef in a significant way. 

Pesticides were found as far as 38 miles into the reef at levels deemed toxic for coral. 

Although coral bleaching has been touted as the biggest threat to the reef in recent years, this is the first government report conducted on water quality in the area and it indicates significant risks to the health of coral in the region as a result of agricultural runoff. 

While the reef is “in moderate condition overall,” the study found that nearly 25 percent of horticulture producers and 12 percent of pastoral farmers were “using practices deemed unacceptable by the industry,” reported the BBC. 

The Herald Sun explained that 14 million tons of sediment from human activities wash into the coral reef annually, originating primarily from cattle farms in the northeast regions of Australia. 

Cyclone Yasi, which swept through the region earlier this year, is thought to have exacerbated the dissemination of sediment and toxins when it churned up waters off the coast of Australia.  Environmental groups, however, point out that the study’s findings are not based upon data from this year, so severe weather cannot fully explain the breadth of the pollutants’ dispersal. 

Similarly, the agriculture industry claimed the dated nature of the information, collected from 2008 to 2009, renders it an inaccurate reflection of current practices they claim are now more eco-friendly.  The data does not show what Steve Greenwood of Canegrowers called, “signs of very, very significant change” in the reef. 

The sugar cane industry has been particularly targeted by environmentalists as one of the primary sources of agricultural runoff and pollution in Australia’s waters. 

“The majority of the 28,000 kilograms of pesticide runoff comes from the Mackay and Whitsunday sugarcane farming region in north Queensland,” reported The Herald Sun. 

Sugar cane farmers claim that no real alternatives to pesticides and weed killers exist to protect their crops, and that banning such chemicals would cause a “major setback” to their industry. 

In particularly hot contention is the chemical Diuron, a weed-killing pesticide currently suspended from use by farmers while the Australian Pesticides and Veterinary Medicines Authority decide whether its harm to waterways is significant enough to justify a ban on its usage. 

The decision will be made by September 30, giving sugar cane growers and other industry representatives just over a month to present a compelling case for its continued application. 

“The Queensland government is investing $175 million over five years to implement a reef plan, including $50 million to implement reef protection laws and research.”

The World Wildlife Fund and other conservation groups are advocating for the ban to protect what is considered the world’s largest collection of barrier reefs, housing 1,500 species of fish and 4,000 species of mollusk. 

In recent years, conservation efforts to protect this prized natural wonder have concentrated upon mitigating the threat of coral bleaching caused by climate change.  Coral bleaching occurs when corals expel colorful algal cells from their tissue as a result of stress.  Their white skeletons are then visible through their transparent outer tissue. 

Sources of stress include changes in water temperature, salinity, extreme light, toxic exposure, and more factors associated with climate change.  Although coral can recover from bleaching if a healthy environment is restored, many also are unable to recuperate and eventually die. 

Conservation efforts are, thus, crucial to protecting the Great Barrier Reef, which is listed as a World Heritage Site and is considered one of the great natural wonders of the world.

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