Pacific Harbour Seal

Pacific Harbour Seal

Author: Tessa March

Identifying Features:

Coat colors of the Pacific harbour seals are varied in shades of white, black, gray or sometimes dark brown. Spots are common markings on the harbor seals, and are often in contrasting colors to the main coat color. Harbor seals have also been known to have an almost red color in the San Francisco Bay.  The Pacific harbour seals have large, round, smooth heads, with no external ear flap, signifying them as ‘true’ seals. Whiskers and large eyes, with large pupils, are other identifying features. Males of this species are often larger than the females. Thick fat (also known as ‘blubber’) covers the seals body. Harbour seals have short pectoral flippers that are covered in hair with five fingers that are used for scratching, defense and grooming of themselves. Their hind flippers also have five fingers. The hind flippers are used to propel the forward and are also used for side to side motions.

Habitat:

Though they often travel up rivers and into lakes, the Pacific harbor seal stays mainly in temperate coastal areas of the north Pacific. They favor being near shore and are often seen on rocky beaches, sandy beaches, bays and estuaries. They can range from Alaska to Mexico.

Prey:

The Pacific harbour seal eats by ripping their prey into pieces, then swallow the pieces whole. The molars of the seal crush shells before swallowing, but food is almost never chewed. They feed mainly on crustaceans, mollusks, squid and various fish, including herring, cod, salmon and sea bass. Feeding is often in shallow water.

Predators:

The main predator of the Pacific harbour seal is the Orca, while other minor predators include specific types of shark, such as the Great White Shark, and humans. Though the Pacific harbour seal is now protected against commercial exploitation, it is still often hunted by some Native American peoples. Harbour seals often get entangled in fishing nets and are strangled and injured.

Life Cycle:

Mating season for Pacific harbour seals often happens in the warmer months of the year, and only one pup is usually born. Female seals are ready to breed about 6 months after birth, and reach maturity around 2-5 years, while male seals are a bit longer, around 5-6 years. It takes about 9-11 months from the pup being conceived to when the pup is born. Pups can crawl and swim right after birth, usually within an hour. Following birth, the pup is protected and nursed by its mother for 4-6 weeks. To breed, Male Pacific harbour seals become very violent and fight each other for the female’s attraction. Male’s will breed with many females’ during the breeding season. Male Harbor Seals live an average of 20 years, and females an average of 25-30 years. The Pacific harbour seals have one of the smallest populations of all the harbour seals, fewer than 4,000. Pacific harbour seals are only seen in groups during molting and breeding.

Photos by D. Young and T. March

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Pacific White-sided Dolphin

Pacific White-sided Dolphin

Author: Isabella de Souza Dias

Common name: Pacific White-sided Dolphin.

Scientific name: Lagenorhynchus obliquidens

Size range: Maximum length of 2.3 meters.


Identifying Features: 

The Pacific White-sided Dolphin’s back is black, the sides are striped light and dark gray, and the belly is white.  They have a dorsal fin that located in the middle of the back and is very curved .  They are a very gregarious species, often seen in large groups that range from 1 to 1000 (mean: 62, median: 15, mode: 6), and will often leap clear of water.

Habitat:

Pacific White-sided Dolphins are found continuously throughout the north Pacific.  In the eastern part of their range, Pacific White-sided Dolphins are found from 20º N to 61ºN. Through out their range they are found in open-ocean and coastal waters.  In Canada, Pacific White-sided Dolphins were primarily considered a pelagic species, however since the mid-1980s their distribution has shifted and they are increasingly common in coastal waters.

Prey (food):

Pacific White-sided Dolphins eat herring, capelin, Pacific sardines, squid, anchovies, salmon, rockfish, pollock, hake and other small fish.

Predators:

Transient killer whales and sharks both eat Pacific White-sided Dolphins. When the dolphins first came back to B.C. waters, it took the Killer Whales a couple of years to figure out how to catch the fast-moving dolphins. Some Killer Whale pods drove groups of dolphins into small bays and killed them en masse but this behavior is no longer as common, suggesting the dolphins have learned to avoid this trap.

Life Cycle:

The maximum age recorded for a female Pacific White-Sided dolphin is 46. The oldest male recorded is 42. Females have their first calf when they are seven to nine years old. Length of pregnancy (gestation period) is around 12 months. When the calves are first born they are approximately one metre long and weigh roughly 15 kg. Females will nurse their calves for eight to ten months and give birth approximately every 4.5 to five years. In B.C. most newborn calves are sighted between June and August but researchers have yet to determine whether there is a defined calving season here.

Illustration by Isabella de Souza Diaz

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River Otter

River Otter

Authors: Cory Davidson, Chandler North and Brianna Sheppard-Murphy

Common name:  River Otter

Scientific name: Lontra canadensis

Size:  1 to 1.4 meters in length (3.1 – 4.5 feet)

Identifying Features   The River Otter (Lontra canadensis) has a muscular body, short legs, webbed feet and rich brown fur.  The fur on their underside may be light brown to almost white.  The River Otter is three to four feet long with sharp claws, a slender body and it has a diamond shaped nose.  It weighs between 5 to 11 kg (11-25 pounds) and its thick tail is 17 to 18 inches long.

Habitat   The River Otter is often found along the shore line of British Columbia including the Victoria area and the Gulf Islands.  Though many resources indicate that they prefer marshes and wooded banks in fresh water areas they are just as at home in the ocean and are commonly found with their families in quiet bays foraging among rocks or on sandy beaches. They create burrows around land habitats close to the water and are comfortable living in the space under docks at marinas.  River Otters stay close to the shore so they can avoid water predators.

(This is a young pup on the left)



Prey (food)   River Otters have a rapid metabolism and must hunt frequently. They eat a variety of animals including fish, clams, and frogs. They also attack beavers, and punch holes in beaver dams to collect and eat the trapped prey which include catfish, crayfish, and insects. In the ocean they often eat gunnels and pricklebacks, sculpins, and various crab species such as the Red Rock Crab (Cancer productus). They use their sharp claws to catch and eat their prey and can hold their breath under water for long periods of time using their large lungs while they are hunting.

Predators   There are a number of predators of the River Otters including bobcats and wolves and even bald eagles may take young pups. In the southern United States they are sometimes ambushed by alligators. They avoid being eaten by either fighting off the enemy or running/swimming away.

Life Cycle   River Otters breed in the winter or early spring. They can have up to three to five young pups each mating season and the pups are born blind and remain blind until five weeks of age. They can live from 13-15 years in the wild, and 20-25 years in captivity. River Otters are very playful and play games to teach their young coordination.

Photos by Lydia Young and David Young

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