All the Way from Canada

An unusual object handed in to the NAFC Marine Centre UHI recently turned out to be a data recording tag that had drifted at least 4,500 km (2,800 miles) across the Atlantic Ocean from Canada, where it had originally been attached to a lobster.

The tag was found washed up on the beach at Burwick, near Scalloway, by David Leask who brought it into NAFC. Staff there discovered that the object was a "pop-up satellite archival tag" (PSAT) which had originally been attached to a lobster in the Bay of Fundy in Canada. The tag was more than 25 cm long even though its antenna and part of its base had broken off during its time at sea.

PSATs are designed to record environmental information such as temperature, depth and location over a period of time while attached to an animal. They then detach and float to the surface where they transmit the recorded data back to researchers on shore via a satellite.

The tag found at Burwick by Mr Leask had been used by Bryan Morse, a researcher at the University of New Brunswick, who was studying the seasonal migrations of American lobsters (Homarus americanus) in the Bay of Fundy. Between 2013 and 2015 he attached tags like this one to a number of large, berried (egg-bearing) female lobsters to monitor their movements between deep and shallow water. This was the first time that tags of this type had been used on lobsters; usually they are used on larger animals such as sharks, tuna or turtles.

NAFC fisheries technician Mark Hamilton thanked David Leask for bringing the tag in and was surprised at its size: "We have tagged lobsters at NAFC but only using small numbered tags. We were really surprised that a tag as big as this one could be attached to a lobster, although American lobsters do grow much larger than our European lobsters. We've sent the tag back to Bryan Morse in Canada and he hopes to be able to download additional information from it."