Saturday 1 May 2021

Authorities in California concerned by rising use of hydrolic pumps to harvest Clams.

The California Department of Fish and Game has raised concerns about the increasingly widespread use of hydraulic pumps to harvest Clams on the northern coasts of the state. The pumps, which first appeared about four years ago, use a mechanism similar to a bicycle pump to inject water into the sediment around the Clams, liquifying the sediment and making them easier to extract. This enables the clammers to extract many more Clams in a given period of time than was possible with more traditional methods, such as digging with a garden fork.

Home-made hydraulic pumps, which are being used to harvest Clams on the beaches of northern California. Beth Schlanker/The Press Democrat.

The use of hydraulic pumps has expanded rapidly in the past year, as thousands of people laid off from their regular employment due to the Covid-19 pandemic have turned to hunting and gathering activities as pastimes which can be carried out in socially distanced ways, and which provide some food for the table and possibly a bit of extra income. This has put particular pressure on protected Gaper and Washington Clams, both of which are subjected to harvesting restrictions. Harvesting of these large Clams is restricted to ten per person per day, which is not unreasonable with traditional techniques, but with the pumps it is often possible to harvest this many Clams in an hour, with daily yields consequently being much higher. To make matters worse, the pumps have made it viable to target areas which are more difficult to access with traditional techniques, usually because they are not exposed by the tide for very long, thereby endangering Clam populations which have, until now, acted as reserves from which more accessible populations can be re-seeded. This overharvesting led to a ban on the pumps being introduced in February 2021, but this has proved difficult to enforce, with many harvesters apparently either ignorant of or indifferent to the ban.

A large Gaper Clam from the coast of California. California Department of Fish and Wildlife/Twitter.

As well as the large numbers of amateur Clam harvesters, professional Clam poachers have become a serious problem on parts of the coast. These poachers harvest particularly large numbers of Clams, not just for personal use, but to be sold on into the commercial seafood industry. The advent of hydraulic pumps has made it much easier for these poachers, not just to extract many more Clams, but to extract them without any chips to the shells, which is common with traditional digging techniques. This often enables the poachers to pass off Californian Gaper Clams as more valuable Geoduck Clams from the coast of Washington, which can sell for up to US$80 per kg.

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