California Sea Lions
Back in 2018, a few of my Circus Siren Pod sisters and I went on Mermaid Dream Retreats to La Paz, Mexico. It was here that we got to experience swimming with California Sea Lions in the wild - something that isn’t allowed in the states. Thankfully, our tails counted as our buoyancy object so we were free to swim and dance with the playful animals.
Zalophus californianus are “eared seals” native to the northeastern Pacific Ocean. They can be found from southeast Alaska to the Pacific coast of central Mexico. They’re very intelligent and easily trained, making them a favorite at many zoos and aquariums.
Pups, weighing about 16 pounds, are dark brown at birth. Around 4-5 months old, they molt their dark brown coat for a lighter brown or even silver coat. Juveniles and females range from blonde to tan, while adult males grow back into dark brown or black coats. Males also have a tuft of blonde hair crowning a pronounced forehead crest. Sea lions have visible ear flaps, long, narrow snouts, broad front flippers, and 3-5 claws on their hind flippers. Females grow to be about 6 feet long and can weigh up to 240 pounds. Males can weigh up to 700 pounds and grow to be 7.5 feet. They live 20-30 years and between 1975-2014, their population had a growth rate of about 7% per year.
California sea lions prefer shallow waters, and like to rest and mate on sandy beaches, rocky coves, marina docks, jetties, and buoys. There are three main populations, the United States, Western Baja California, and the Gulf of California. In the winter, males often migrate to feeding areas in Alaska and Canada, where females and pups tend to stay near the breeding colonies. Breeding grounds range from California's Channel Islands to central Mexico.
Breeding normally occurs from June to August, with pups being born May to June. Females can mate again 3-4 weeks after giving birth. Sea lions reach sexual maturity around 4-5 years old, but don’t reach social maturity until they’re 9-12 years old. Males are polygamous and can have up to 14 females in their breeding territory, which they defend aggressively with physical displays and vocalization.
Mothers nurse their pup for 1-2 days, then head out to sea to feed for 2-5 days while the pup remains ashore. While the mother is gone, the pup doesn’t eat. This cycle repeats for about a year until the pup is weaned off the mother.
Feeding takes place offshore in coastal areas. Sea lions often find their prey in upwell currents, including squid, anchovies, mackerel, rockfish, and sardines. However, sea lions are also opportunistic and will take fish from commercial fishing gear, fishing lines, and from fish passage areas on rivers and dams.
Sea lions are very social creatures, both on land and in the water. Males bark like dogs, while females and pups have unique vocalizations special to the individual. Females and pups also have a unique scent to identify them as well.
Females will fight other females to protect their pups, and males will aggressively defend their territory, but sea lions are very skittish when it comes to humans.
Sea lions also display what’s called “rafting”. This is when they hold their flippers above water, motionless, for a long time to rest and regulate their body temperature. When they do this, it can look like the sea lion is caught in a net.
When rafting, they aren’t in any danger, however entanglements in nets and other fishing gear is a real threat for sea lions! Traps, pots, and gillnets can get caught on the sea lion, leading to fatigue, compromised feeding abilities, injury, and even death.
Other threats to sea lions include biotoxins from algal blooms. Sometimes algae can grow out of control, especially in warmer water. Because sea lions are top predators, as they consume prey, the toxin builds up in their body. This can lead to seizures or domoic acid poisoning, which can cause death.
Of course, humans also pose a threat to sea lions. Harassment from humans and boats is a real issue. Additionally, when sea lions get used to eating off of fishing lines, it disrupts their natural hunting skills. Fishermen and boaters sometimes get angry at the sea lions eating their catch, and retaliate by purposefully shooting or killing the sea lion.
Not all hope is lost, though! Sea lions are part of the Marine Mammal Protection Act of 1972, which “prohibits taking of marine mammals, enacts a moratorium on import, export, and sale of any marine mammal or marine mammal parts or products within the United States”. This act also requires humans and pets to remain a safe distance of 50 yards away from the sea lions at all times.
NOAA, the National Oceanic and Atmospheric Administration, is doing several things to increase the conservation and protection of sea lions as well as increase the science that is known about sea lions. Some main bullet points of things they’re currently implementing include “reducing interactions with commercial fishing gear, minimizing harassment and illegal feeding, responding to dead, injured, or entangled sea lions, encouraging responsible viewing, minimizing vessel disturbances, accessing abundance, survival, and birth rates of sea lions, monitoring their food habits, and describing disease ecology and human sources of death”.
There are a few things you can also do to help out! Remember to keep your distance - 50 yards minimum between you and your pets and the resting sea lion! Try to limit your viewing to 30 minutes or less as well. Report any distressed sea lions to a local protection agency (here in Maryland we report to the National Aquarium for distressed seals and turtles), but never approach the animal. Please report any violations to the NOAA Fisheries Enforcement Hotline, available 24 hours a day, 7 days a week in the United States - 800-853-1964.