Sea lions heating up for breeding

California sea lions gathered on Port Dock 5 to sunbathe Saturday afternoon. They’ll leave Yaquina Bay for a few months this summer to breed in the waters near California’s Channel Islands. (Photos by Kenneth Lipp) California sea lions face off with “threat gestures” on Port Dock 5 on Saturday. Breeding season for the animals begins in late spring, and the male pinniped denizens of the port are growing more aggressive as they prepare for displays of dominance, bidding to win a mate when they return to the waters off southern California.

YAQUINA BAY — Spring comes in like a lion.

As their breeding season approaches, the mostly male sea lions of Yaquina Bay are growing hormonal and more aggressive as they prepare to head south for courtship.

The pinnipeds that crowd the docks of Newport’s harbor are California sea lions. The typical adult male is close to 8 feet long and weighs between 700 pounds and a half ton, while adult females are usually 6 feet long and weigh less than half as much. The Steller sea lion is also found in the area but tends to stay away from harbors, favoring to haul out on sea rocks and buoys offshore. The most obviously recognizable differences between sea lions and their cousins, the seals, are that the former have external ear flaps and walk semi-upright with their forelegs.

Because the females don’t need to migrate, with rare exceptions, and remain mostly in waters near California’s Channel Islands to wean their pups, the jetties, piers and beaches of the Oregon coast are occupied almost exclusively by males, whose full range extends from central Mexico to southeastern Alaska. According to Jim Rice, stranding coordinator for the Marine Mammal Institute at Oregon State University, the boys are getting geared up to vie for a mate when they return to California during late May and June.

“Their testosterone is ramping up, and they’re starting to engage in more displays of aggression and dominance,” Rice said. Most of those displays are heated jousting and what Rice called “threat gestures,” but once they’re in southern California and establishing territories, among which their female counterparts will shop for a suitor, the fighting words can turn to serious biting, and many of the Newport cohort bear scars from those battles when they return to northern climes in August.

“The most aggressive and dominant animals will be the most successful at finding a mate,” Rice said.

The dog-faced sea mammals can be found in great numbers on the area’s jetties and piers outside of summer breeding season, and Port Dock One on the Bayfront provides easy access to observe the creatures without significantly disturbing them. The Marine Mammal Protection Act makes it illegal to hunt, capture, kill or harass sea lions, with limited exceptions for the deterrent hazing of individual nuisance animals.

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