MTN 68:35 IMO Project Review: Clean-Up at Karan Island

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IMO Project Review: Clean-Up at Karan Island

The clean-up of Karan Island [following the Gulf War] was regarded as a first-priority activity by the IMO and MEPA. Karan Island is the most important nesting site for green turtles in the Persian Gulf, which is itself an important component of the world's nesting areas for this endangered species. The island is also an important nesting site for the hawksbill turtle, which is also an endangered species because its shell is used to make jewelry and curios in some parts of the world. Finally, the island supports rookeries for lesser crested terns and other bird species on the global migratory routes. Because these birds are migratory, severe impacts on their reproductive effectiveness could be realized in several other nations.

The oil posed at least four potential threats to the turtles:

Because adult turtles have been known to eat tar balls, it was feared they would ingest oil and tar as they approached the island to nest. The materials can cause blocking of the digestive tract and death;
Oil has been demonstrated to cause irritation of mucous membranes in turtles, such as those in the eyes, nose and throat, leading to inflammation and infection. Loss of sight, inhibition of respiratory function, and similar pathologies can reduce the ability of the turtles to survive. While these impacts would not have affected the 1991 nesting activity [because the beaches were cleaned before nesting began], they could have impacted the population of green turtles as a whole;
Direct contamination of eggs could occur either by oil being deposited high enough on the beach to contaminate the nests or by oiling of the adult turtles as they made their way across the oiled beach to the nesting sites. It was feared that such direct oiling would inhibit development of the eggs;
After hatching and digging themselves from the nests, hatchlings make their way over-land to the water. It was feared they would become oiled during transit and suffer heavy mortality.

The island was visited on 14 March 1991 by IIAT staff accompanied by approximately 80 British Royal Air Force and U. S. Marine Corps volunteers. The entire shoreline was found to be oiled, with the primary nesting beach on the western shoreline covered by a tar mat up to 35 cm deep and 30 m wide. The island was also covered by a great deal of debris, pre-dating the oil spill but capable of interfering with transit of turtles to their nesting sites. The military volunteers collected several tons of this debris and burned it in the central part of the island.

Because the green turtles were expected to begin nesting in early May, clean-up of this island was properly assigned a number one priority, although it was decided to wait until the threat of additional oil stranding was substantially removed. Clean-up was planned to be completed by 30 April 1991, but the job was more extensive than anticipated, and was not completed until 5 May. Clean-up consisted of the following steps:

Digging several trenches, well above the area that the turtles use to nest, for disposing of oil and oiled sand recovered from the beach.
Saving sand removed from the trenches for beach replenishment.
Removing tar mats and oiled sand from the beaches mechanically, disposing of it in the trenches, and covering the oiled sand with two feet of clean sand originally taken from the trenches.
Replenishing the cleaned beaches with sand remaining from digging the trenches.

A verbal report in November 1991 by Dr. John Grainger, an environmental scientist with the National Commission for Wildlife Conservation and Development in Riyadh, indicated that results of this project were favourable. Dr. Grainger stated that turtle nesting apparently was unimpeded by the oil spill, and that bird nesting was even more extensive than in recent years. He attributed the bird nesting success to clean-up of debris, which made more land available to nesting activity. It appears that this project was effectively conceived and executed. In addition, the urgency imposed by the timing of annual turtle and bird nesting activity was properly considered as requiring that this project be undertaken with a very high priority. Source: International Maritime Organization IMO News, 1994(1):25-27.