Early next month, Dr Margaret Klinowska and her colleagues from Cambridge University will set off for the Moray Firth, north Scotland, to verify that their invention can divert dolphins away from drift nets. She said yesterday that they needed about pounds 100,000 a year for three years to develop and test the device properly, whereas at present 'we have to make do with the odd pounds 2,000 that we can pick up'.
The team carried out its first tests last year and the preliminary indications were that the device worked. But those tests were only possible, she said, because of a grant from the Co-op. This year's tests are being financed by money saved from an EC grant.
Scientists believe entrapment in fishermen's nets is a major cause of dolphin deaths. Because they are air-breathing mammals, the dolphins will drown if they become entangled in underwater drift nets.
Professor Guiseppe Notobartolo di Sciara, from the Tethys Research Institute in Milan, said that fishing was the biggest single cause of dolphin mortality in the Mediterranean, far more important than pollution or disease.
He said that even though EC regulations now forbid the use of nets longer than 2.5 kilometres (1.5 miles), some fishermen were using nets up to 15 kilometres (9 miles) long. He called for the establishment of dolphin sanctuaries in the Mediterranean.
Dr Thijs Kuiken, from the Institute of Zoology in London, said that of the 55 dolphins which were washed up on British shores last year, post-mortem examinations revealed that 15 had died as a result of being entangled in fishing nets.
Dr Klinowska's group, together with sonar engineers from the University of Loughborough, have discovered that small floats which are standard equipment on 'bottom-set' nets can reflect the sonar signals that dolphins send out when navigating underwater.
The floats are plastic and shaped rather like an egg, about the size of a small fist. In normal use they are not attached to drift nets.
By placing these floats at intervals of 2 metres (2.2 yards) on drift nets, the researchers can make the nets appear to the dolphins as if they were solid barriers. Instead of swimming straight into the nets, the dolphins avoid them.
Dr Klinowska said that adding so many of these floats to a net increased the price by about 10 per cent and also made them more cumbersome to handle and store. Further work was needed to refine the system, but the group was being handicapped by lack of funds.
Nonetheless, because it used components which were already mass-produced for the fishing industry, the system was 'cheap and cheerful', Dr Klinowska said.
'Fishermen are dying to get these things on their nets,' she continued, partly because they wanted to save their equipment and prevent the loss of nets that sometimes occurs when dolphins do get entangled, but also because in many parts of the world it is considered unlucky to catch dolphins.Reuse content