All of the stranded seals that Schofield and his colleagues rescued were lethargic when they were found and had high levels of liver enzymes and chest congestion.
The scientists speculate that the hooded seal population may be suffering a virus, something like a seal version of a human flu, although it's too early to tell. Another possibility, Schofield suggests, is that climate change may have contributed to a delayed birthing season and the pups became confused by the warm water and swam the wrong way.
Lost contact with 12-CC, Schofield said, may mean that he died or that his satellite tag failed or fell off and is now somewhere in the ocean. Such tags can only send a signal when animals surface for air.
The tag was adhered to the fur on 12-CC's upper back, so he would lose it naturally during the annual molting season.
"When we released 12-CC he was pretty feisty," said Schofield. "During his week after release 12-CC was moving at about 200 to 300 miles per day, which suggests he was doing pretty well."
Schofield said he and his colleagues have attached satellite tags to turtles, porpoises, and other marine mammals, and most don't seem to mind or even notice. "But when we released 12-CC on the beach," he said, "he spent at least half an hour rolling in the sand trying to dislodge the tagjust like the way a dog tries to get rid of a collar." Schofield thinks 12-CC probably managed to rid himself of the tag.
Explaining 12-CC's heading south rather than north toward his fellow seals, Schofield said rehabilitated seals typically wander a bit before they head in the right the direction. Unfortunately, the Baltimore researchers don't have signal data to know whether 12-CC got back on track.
Schofield, who coordinates the Marine Animal Rescue Program, part of a larger network devoted to saving stranded animals from the sea, is not sure whether the recent strandings are part of a large die-off of hooded seals triggered by disease, pollution, climate change, or some other factor. The seals are usually found stranded in the winter months, so the months ahead may help the researchers determine whether the lost and sick seals are part of a much larger problem or just an anomaly.
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