NB researchers monitor invasive tunicates

Lurking just across the St. Croix River, an invasive species with a deceptively innocent name has slowly been making its way toward New Brunswick, and it has some researchers worried.

The pancake batter tunicate, which resembles its namesake, blankets everything from docks to sea floors and poses a threat to the local ecosystem’s diversity, Jennifer Martin said. She is the lead researcher on a team of scientists and divers that will head to Campobello Island and Deer Island at the end of the month to spend two days monitoring the spread of the species that has been causing problems for north-eastern American states since it first snuck into the area aboard a mussels ship from Japan.

Tunicates, also known as sea squirts, are invertebrate filter-feeders that can largely carpet ocean floors. They usually move around by hitching a ride on something faster, such as a boat.

“It can smother and out-compete anything that is in our natural environment,” Martin said.

The researchers at the St. Andrews Biological Station have been monitoring the spread since 2009. At last inspection it was growing on pontoons and wharves in Eastport, Maine. They haven’t yet seen it in New Brunswick waters.

But Martin said it wouldn’t be a big jump to make. The two sides have nearly identical environments.

In late September, St. Andrews researchers will lead a diving expedition to Eastport, where they will study the invasive species to determine if there has been any progress since last year.

The researchers from St. Andrews Biological Station will be joined by counterparts from Halifax, Montreal and P.E.I., as well as some partners from the Woods Hole Oceanographic Institute in Maine.

This year will be their biggest team yet, at about 14 people in total, Martin says.

While species that get buried beneath its quarter-inch shell still seem to be able to breathe, the tunicate impedes growth. It can also latch itself to and weigh down fishing gear, aquaculture structures and buoys.

Unfortunately, Martin said there’s not a lot people can do once it’s there. They can scrape it off surfaces with a paint chipper, but this poses possible threat of spreading it further.

On Sept. 27 and 28, divers will go down during low tides, when the current is calm, to take photographs of the species and retrieve samples, which will be taken to the lab for study. They will also drag for scallops, which will likely haul up some of the tunicates at the same time, if present.

Tunicates can also be monitored by deploying collectors (plates) attached to floating docks or buoys.

In recent years, there has been increased efforts to study the invasion of aquatic species, as international trade expands and more vessels enter the Bay of Fundy.

To date, the Bay of Fundy tunicate monitoring program has provided evidence that the golden star tunicate, and the vase tunicate are present in the Bay of Fundy.

The pancake batter tunicate has been observed on the U.S. portion of Georges Bank and in northern Maine, including Eastport in Passamaquoddy Bay. But as Martin said, nature knows no political boundaries.

Previously published by the Telegraph-Journal; Sept. 1, 2011

East N.A. coast among places that merit protection

The waters around New Brunswick and along the northeast American coastline have been cited in a new study as being among the top nine marine places in the world that merit protection.

The study criteria looked at how many marine mammal species are there, how rare they are, and how at risk they are from human influence.

While 20 sites were highlighted worldwide, the report’s authors determined that by preserving just 2.5 per cent of the ocean, they could protect the vast majority of marine mammal species.

“We’re in a very important species extinction crisis,” researcher Gerardo Ceballos said in a telephone interview.

Like all the hot spots, eastern Canada is at a medium to high level of dangerous human impact, Ceballos said. He and Sandra Pompa Mansilla co-authored the study from the National Autonomous University of Mexico.

They worked on the study for four years with a fellow researcher at Stanford University and published the paper in the Aug. 16 edition of the Proceedings of the National Academy of Sciences.

The key sites seem to congregate in upwelling oceanic areas, where cold currents meet warm ones. These often produce areas of high primary production, which are good feeding grounds for marine mammals.

Southern New Brunswick, which is known for its whale-watching industry, serves as the summer home of the right whale, an endangered species that was pinpointed as one of the animals of particular concern by the scientists. Other species frequenting the Fundy area are the minke whale, the humpback whale, the finback whale and white-beaked Dolphins, among other species.

Although they are known to visit, it’s considered rare to see a blue whale, sperm whale, killer whale or beluga whale.

Marine mammals provide some of the best-known cases of population and species extinction through overexploitation, the study states.

For the North Atlantic, the study lists the whale-watching industry, toxic waste dumping and vessel collisions with whales as the most dangerous threats to the rich marine population in the North Atlantic.

The researchers are the first to combine various habitat maps of marine mammals around the world into an all-inclusive map showing the hot spots, Mansilla said from her university office in Mexico.

But Ceballos said their study “is a guideline for some of the most important places … but it doesn’t mean that the rest of the areas shouldn’t be taken into account.”

The other nine sites are located off the coasts of Baja California in Mexico, Peru, Argentina, northwestern Africa, South Africa, Japan, Australia and New Zealand.

Of the 129 species of marine mammals on Earth, including seals, dolphins and polar bears, approximately 25 per cent are facing extinction, the study said, ranging from being considered vulnerable to critically endangered.

Previously published by the Telegraph-Journal; Sept. 6

Researchers monitoring salt water in wells

Sea water is gradually seeping into the drinking water wells along the Northumberland Strait, a University of New Brunswick researcher says.

While no one’s gotten sick yet the future looks grim, Kerry MacQuarrie said.

Climate change experts warn of rising sea levels, which have the unfortunate side effect of leaving groundwater sources ruined by salt water intrusion.

MacQuarrie is looking specifically at the coastal community of Richibucto, where the water has a history of being too salty. The two-year project is part of the Atlantic Regional Adaptation Collaborative, which is a branch of a larger federal climate change planning initiative.

“We would say that the issue is definitely there in Richibucto now,” said Robert Hughes, an adaptation co-ordinator at the Department of Environment. Hughes manages the province’s various climate change adaptation programs, which includes MacQuarrie’s salt water intrusion project.

While Richibucto’s water is currently well within the Canadian drinking water standards, studying the case could illuminate possible future problems and solutions, MacQuarrie said. When the water does eventually become too salty, Richibucto could serve as the model for other communities’ action plans.

About a decade ago, Richibucto was forced to abandon a well and drill a replacement in a new location when the salt water intrusion became a real issue. It resolved the problem, but the town’s seaside location still puts it at risk.

While salt is essential to a healthy diet, too much can be dangerous. Sodium and chloride occur naturally in groundwater, but high levels can turn the water corrosive and damage household plumbing, not to mention cause a salty taste.

“You can’t drink seawater, as everyone knows,” Hughes said.

But rising oceans aren’t the only cause. Higher demand for water means excessive pumping and the groundwater doesn’t have time to replenish with fresh rain or snowmelt. With nothing to stand in its way, the lower, denser salt water is suctioned into the well’s reserves.

“The concern is that if salt water really gets into those aquifers, it’s pretty much there. It doesn’t go away again. That groundwater area is no longer useful,” Hughes said.

MacQuarrie is measuring sodium and chloride levels in Richibucto’s wells with his project partner Karl Butler, a geophysicist at UNB.

Working with two of the university’s master’s students, they shoot electric currents about the power of a car battery through the water. Electricity passes through salt water more easily than fresh water, so the measured conductivity indicates daily levels. The technique is well-established and causes no harm to humans or the water, MacQuarrie said.

With their data in hand, MacQuarrie and Butler then create 3D worlds on their computer screens in which they control a well’s hypothetical pumping rate or possible sea-level rise, among other variables, and see the effect. They also assess where the salt water is beneath the surface. Combined, the findings could be the basis for an action plan.

The project ends around next March or April, MacQuarrie said.

Previously published July 20, 2011; Telegraph-Journal