Two major food sources for millions of birds and fish in the Bay of Fundy may have been brought to the Maritimes unwittingly by early European explorers.
Hediste diversicolor, or mud worms, were likely carried to the shores of the Bay of Fundy by early European explorers, according to new research from the University of New Brunswick. (Jim Wolford/Government of Nova Scotia)
Research from the University of New Brunswick suggests mud shrimp and mud worms are invasive species from Europe carried across the Atlantic in ship ballasts, perhaps that of Samuel de Champlain.
"There's no way to tell for sure," said researcher Tony Einfeldt, "but it very well could have been him."
Einfeldt's conclusion comes from genetic analysis — comparing the genes of the Bay of Fundy populations of mud shrimp and mud worms to those on European coastlines.
A female Corophium volulator, or mud shrimp, is shown in its protective U-shaped burrow. (Jim Wolford/Government of Nova Scotia)
"We can tell where they came from because the genetic identity of both species in the Bay of Fundy matches that of those in Europe," he said.
To explain how they got here, Einfeldt had to match movement patterns of the invertebrates with movements in history.
"We know that both of these species are not very good swimmers. They don't disperse naturally very well," he said.
Many invasive species can be traced to ships' ballast water.
UNB researcher Tony Einfeldt collected specimens in Europe to compare with those on this side of the Atlantic. (Submitted by Tony Einfeldt)
Large ships pump water in and out to offset cargo loads. Sea creatures get sucked in with the ballast and can be borne great distances.
Neither shrimp nor worms have ever been found in the ballast water of any modern ship.
However, the first ships that crossed the Atlantic didn't use water for ballast, but rather rocks, sticks and mud.
Mud is where both of these species make their home.
"And the only ships that we know of that did this were the earliest ones used by the expeditions of Samuel de Champlain in the early 1600s and Henry Hudson," he said.
Tony Einfeldt looks for mud shrimp and mud worms in Maine, just south of the Canada-U.S. border. (Submitted by Tony Einfeldt)
Einfeldt said that is likely how they were transported.
Einfeldt's genetic work has been able to pinpoint several introductions of these species along the East Coast.
"The Bay of Fundy populations most likely came from France and the Bay of Biscay," he said.
"A second introduction that occurred in the Gulf of Maine is more likely from northern Europe, like the Norway, Germany, Denmark area," said Einfeldt.
The researchers are now using new techniques in hopes of determining exactly which coast they came from.
The semipalmated sandpiper is one of many birds that feed on mud shrimp and mud worms on the Fundy coast. (Nature Canada)
Einfeldt said these invertebrates have become extremely valuable to the Maritimes' ecology.
"The reason that many of these birds and fish come to our mud flats is to feed on these prey. There's so many of them," he said.
"The idea that so much of what our ecosystem runs on came from our history — it's very exciting."
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