Lobster will be harmed if waste water pipe allowed

Opinion
Pictou-Advocate-opinion

To the Editor:

This writer has just completed researching some of the many studies done about how cold water lobster hatch and eventually become market size. Female lobsters develop eggs that adhere to the shell overwinter and hatch the following late June into July. These larvae live in the top two meters of the water for about 20 to 30 days while they grow through three stages and finally reach stage 4 and then fall to the water bottom where they live in the mud/sand/rocks for at least five years and reach a weight of 500 grams (1 pound). Each shell moult sees the lobster gain about 40 per cent in weight. By year seven to eight they reach 750+ grams and can be caught and sold. Some are not immediately caught and live to be much larger.

It is the life of the hatchlings or larvae that was my research. It’s a lengthy story but I’ll shorten it to this summary: Cold water lobster are found from the coast of Gaspe down along the eastern shores of N.B./N.S. and along the North Shore of N.S. and around Cape Breton. Water temps during the hatching months ranges from 10C at Gaspe to about 15C down off Caribou, Chance Harbour, Little Harbour and beyond. The PEI shore has similar temps.

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Larvae live well in 10C water and better in temps up to 14 C. After that temp there is a lot of mortality until at 22C — none survive. The warmer the water the faster they grow and rate of survival lowers a lot. If they survive until stage 4 size they drop down to the floor of the water and make homes among the rocks, mud, sand where most will live for another five years — moulting each year and increasing weight about 40 per cent at each shell moult. By years six to eight they have reached a weight of 1.5 lbs and become legal catch. Some escape and live on for many more years .

The temperature of the waste water from the proposed pipeline from the pulp mill across the Pictou Harbour and out to Northumberland Strait is estimated to be 25C in cooler months to 37C in warmer summer months. All 70 to 90 million litres. This being flowed into 15C N. Strait water will gradually warm the coastal waters the larvae live in. Every degree above 15C will shorten the life of a cold water lobster larvae. When the temperature reaches 16.5C survival rate lowers until at 22C none survive .

Gradually, over the next five years, the catches are reduced until there is almost no legal marketable lobster to catch.

No one knows how far the mill-heated water will be blown by water surface winds. Thus no one knows how far away the larvae will be affected.

Climate change is already warming the surface waters and adding warmed mill water to the mix must not be allowed to take place. Waste that reduces the oxygen in the water compounds the danger to all life including fin fish. There must not be a waste water pipeline from the mill.

Ref: Journal of Crustacean Biology, Vol 33. Issue 4, pages 527-536.

Also, Bigelow Laboratory for Ocean Sciences at West Boothbay, Maine. Jessica Waller study.

Don Wilson,

Brule Point

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