Sharks caught on baited fishing lines flee to deeper waters after hooked, say marine biologists in a new report. Twenty-one tiger sharks hooked off the coast of Brazil on longlines -- a commercial fishing technique responsible for half of the global shark catch -- were tracked by scientists for up to 24 months after the sharks' release.
In every instance, after scientists freed the animals from the fishing line, the sharks steered clear of the area where they were hooked because of the stress of capture. (The tiger shark making the closest return came within roughly 10 miles of where it was caught, but only after a span of 74 days.)
None of the animals died after being released, except for a single shark that perished, unrelatedly, after 45 days. When sharks are properly released from hooks, they "experience negligible post-release mortality," the researchers write. A mandatory release of live sharks caught by fishermen, they conclude, could ease the industry's pressure on tiger shark populations.