As they tracked a young male beluga whale rescued from the Nepisiguit River near Bathurst last week, researchers were growing increasingly concerned about his health, but on Wednesday morning there were encouraging signs.

'Swimming offshore means he is strong enough to fight the current.' - Robert Michaud, marine biologist

Robert Michaud, a marine biologist and the scientific director of the Group for Research and Education on Marine Mammals in Quebec, said it has been a roller-coaster ride.

"Remember that the vets were concerned with the health of the animal when we captured it, and when we released it — its blood sample showed ... the sodium was very low, so the prediction or the prognostic was not so good."

Over the last three days, satellite transmissions from the whale showed the mammal constantly moving downstream, which Michaud said was a big worry. It suggested the whale might not have the strength to fight the current.

Robert Michaud

Marine biologist Robert Michaud says the beluga whale has moved farther offshore and the transmission times from a satellite tag are coming in over a larger window — both signs the whale is getting better. (GREMM)

"We felt very bad," Michaud told Information Morning Fredericton.

On Wednesday, however, the research team received "encouraging signals" from the whale, now near Saint-Fabien, a community about 65 kilometres downstream from where he was released.

"Yesterday, he started moving offshore, so he's still within the range of normal beluga summer distribution," Michaud said. "So he may be in contact with beluga whales. 

"Swimming offshore means he is strong enough to fight the current so ... hopefully it's going to be a long story to follow — that will mean that the animal will have made it."

Next few days critical

beluga on plane

The beluga was carried out of the Nepisiguit River and transported to Quebec on a small plane last Thursday. (Patrick Bergeron/Radio-Canada)

Scientists are hoping to find the whale and check up on him but between bad weather along the St. Lawrence River and satellite locations that aren't received in real time, it has been very difficult, Michaud said.

"If summer can come in with less fog and less wind, we should be able to have visual contact in the next day."

The other encouraging sign from the satellite transmissions has been the window of time during which that information is received.

"The satellite tag on his back is programmed to send about 250 uplinks a day," Michaud said. "We ask the tag to send those uplinks every time it can, and it can send the signal only when the tag is at the surface and since the first day we received all the signals within about two hours."

On Tuesday night that window increased, suggesting the whale is spending less time at the surface.

"This is the other encouraging news from last night — the transmission window was a bit larger than the other days. So we don't have much, but that movement offshore, that prolongation of that window, is for us encouraging signs."

Continuing to collect information

Michaud hopes researchers will be able to locate the whale and gather more information about whether he has joined a pod.

"Hopefully, this guy will find peers and will make bonds as this would be the best chance for him to reintegrate into this society on the St. Lawrence."

Michaud said the next few days will be critical for the whale, which was nicknamed "Piz" by a researcher, after the Nepisiguit River where he was rescued.

It may take several weeks, according to researchers, for the whale to regain his strength and begin a "normal" beluga life.

With files from Information Morning Fredericton