Stop feeding tuna before they are full, EIA on Malta ranch suggests

The EIA warns of a series of negative environmental impacts as a result of extending existing tuna pens in the area

The tuna penning zone may have a major negative impact on marine water quality
The tuna penning zone may have a major negative impact on marine water quality

An EIA on the doubling of tuna cages by Azzopardi Fisheries from 12 to 24 in an ecologically protected area off Sikka l-Bajda, five kilometres from the coastline, suggests that proper management may reduce negative impacts.

One of the proposals made in an Environmental Impact Assessment to mitigate the negative environmental impact of tuna pens is to stop feeding the tuna before they are “satiated” to “minimise food loss,” and thus reduce the deposition of tuna feed on the seabed.

The EIA warns of a series of negative environmental impacts as a result of extending existing tuna pens in the area.

According to the study the tuna penning zone may have a major negative impact on marine water quality resulting from uneaten feed settling on thee seabed, discharges of oil and bilge waters, and discharge of sewage from marine vessels.

The EIA warns that the discharge of fish oils can also affect beaches and coastal areas, as has happened in recent years. “This would impact bathing, yachting, diving, and related recreation, tourism, and the general quality of life of coastal residents and visitors.”

According to the EIA, the severity of this impact will depend on the amount of fish oil released into the marine environment during feeding and the amount of oils that escape the farm and the collection systems deployed to counteract this issue.

The EIA proposes a number of measures to avoid these negative impacts including supervision of tuna feeding by divers and to stop feeding tuna before they are satiated to avoid loss of feed.

Other measures proposed include the availability of “additional oil collection services outside the farm to ensure immediate collection of any slick escaping from the farm.”

A number of vague proposals made include “good practices aboard ships to minimise discharges, noise, light, and littering,” and the use of oil skimmers to collect oil released in each cage.

The tuna farm extension may also have a negative impact on breeding seabird populations resulting from increased light pollution and the attraction of predatory sea gulls.

To avert these impacts the EIA suggests a downscaling of activities at night, the setting up of a seabird monitoring programme, the monitoring of gull colonies and the training of staff “in appropriate bird handling and reporting.”

The reason given for doubling the number of cages is to ensure that the tuna fish have sufficient space to allow them to reach optimal size before they are killed.

The decision to relocate the tuna pens from Comino and St Paul’s Bay was taken amidst a national outrage over reports of sea sludge polluting the Maltese coastline.

But the decision was opposed by environmental groups like Birdlife who lamented the absence of studies before the temporary location to a designated marine Natura 2000 site. The current application to double the number of tuna pens will still respect the company’s 3,300 tonnes of fish quota.

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