Some types of seaweed are disappearing from the Bay of Fundy, according to scientists at the University of New Brunswick (UNB) and at the Huntsman Institute in St. Andrews, New Brunswick.
The reasons for the disappearance are far from clear.
“Something’s happening,” says Gary Saunders, Canada Research Chair in Molecular Systematics and Biodiversity at UNB. “There are clear signs of stress. We’re seeing a lot less red seaweed and a lot more green algae.” He explained that red seaweeds usually cling to the rocks just below the water’s surface, forming meadows, and these meadows create habitat for baby fish to big lobsters.
Saunders adds that the meadows are becoming thin in some places and have totally disappeared in others.
“I take my class regularly to L’Etete,” he says. “We’ve been monitoring there since ’98. In fact, a student noticed the changes then, and students set up the monitoring system.”
Saunders says he and his students have come up with more questions than answers. “There are a lot of issues here. L’Etete is close to some fish farms, but there’s no evidence of any direct link to fish farms.”
As for the Lepreau nuclear plant, he says, “any evidence there is really quite anecdotal. The physiology doesn’t seem to have changed, but we are noticing a lot of periwinkles where they weren’t before.” Lepreau is located on New Brunswick’s south coast, east of Campobello.
Overall, Saunders says, “is this phenomenon part of natural cycle or something else? We honestly don’t know. I’m hoping we can run for 10 years at least if I can find the resources to do it.”
Gerhard Pohle, Associate Director of the Huntsman Marine Science Center (HMSC), the co-author of a study on life in the Bay of Fundy says there may be a link to fish farms.
“My experience lies with bottom-living animals,” he said, adding that his study “shows that the community structure of benthic organisms (which, unlike planktonic ones, cannot move away from impacts) has changed significantly on a regional scale (i.e. not just at individual farm sites) in the 1990s. In the area with the longest period of aquaculture (Lime Kiln Bay) we showed increased biological stress and decreased benthic diversity with a corresponding increase in nutrient pollution. Similar work on recovery after cessation of aquaculture operations showed that the benthos takes years rather than months to recover.”