Fishes and Cetaceans

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ON THIS PAGE:

Fishes:

  • Spiny Sand Shark
  • Grunt Sculpin

Cetaceans:

  • Orca
  • Pacific White-Sided dolphin

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Spiny Sand Shark (Squalus acanthius)

Also known as a dogfish, this small shark lives along the coasts of all the continents except for Antarctica. They are one of the most common species, but because of their popularity in Europe as a food fish, and for their use in household products and dissections, have been overfished.  Spiny sand sharks are named for the slightly poisonous spines at the front edge of their dorsal fins. When caught, the sharks will reach their tails around in an attempt to stab the predator. They are most often grey, or grey-brown, and sometimes have a spotted pattern on their backs.  Spiny sand sharks are benthic, meaning they live along the bottom (“sand” shark) , leading them to depths as much as 700m. They live up to 100 years, and gestate their young up to two years. The males grow to one metre, while the females grow larger, to a metre and a half.

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Grunt sculpin (Rhamphocottus richardsonii)

Where to begin? These fish are quirky, adorable animals, with a list of qualities that make them bizarre. The name grunt sculpin comes from the strange noises they make, although no one seems to know the reason behind them. Their body shape is stockier and more exaggerated than most sculpins, with a tiny tapered tail, enormous head and seahorse-like mouth. The orange of its spiny pectoral and caudal fins give it a slight clownfish look. These fins also make them rather clumsy swimmers, so instead they mostly hop along the bottom, or hide in giant barnacle shells, imitating the shape of a closed barnacle with its nose and colouration.  They eat plankton, baby fish and small crustaceans,  and are eaten by certain sea birds.  The mating habits of grunt sculpins are also special: females chase males into empty barnacles, lay their eggs them leave the male to fertilize and guard them from predators.

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Orca (Orcinus Orca)

The orca is an iconic species in the Salish Sea, and thanks to its enormous range, practically everywhere else too. Found in the Arctic, Antarctic, tropics and temperate regions, they are one species with many populations, varying in size, colouration, diet and behaviour. The three types found off of British Columbia are resident, transient and offshore orcas, although offshore are rarely seen and not as much is known about them. All orcas live in matrilineal (led by the eldest female) groups called pods, but the size depends on the type, food availability and seasonal activity. Transients feed on other marine mammals like seals, porpoises and even baleen whale calves. They travel fairly unpredictably and in small, more changeable groups. The resident orcas, who eat fish (mainly salmon) include two general groups who return annually to their region: the northern residents, about 200 individuals living between northern Vancouver island and Alaska, and southern residents, who inhabit the Salish Sea during summer and the coast from California to Haida Gwaii in the winter.  With only 85 members, divided into three pods, they are the only orcas officially deemed endangered. Lack of chinook salmon, an increase in boat traffic and pollution are factors in their decline. They are a favourite species of whale watchers and scientists, and have been studied extensively.

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Pacific White-Sided Dolphins (Lagenorhyncus obliquidens)

Unlike the classic long-nose thin body we often expect in dolphins, Pacific White-Sided have a stubby beak and thick trunk, with a large curved dorsal fin. They live in pods of up to 1000 individuals, or more when forming superpods, but are more often found in groups of ten to one hundred, and sometimes fewer on the coast of British Columbia. They have long whitish-grey patches along their sides (obviously) as well as on their dorsal fin, a pale stripe along their backs and a pure white ventral area.  Pacific-white sided dolphins are very playful and perform acrobatics, especially around boats, where they can ride waves along the bow.  The North Eastern Pacific range of this species includes around 27 000 dolphins, from California to Alaska. Depending on oceanic conditions, such as the El-Nino cycle, these dolphins can be found in their more pelagic range, out in the open ocean, or in areas along the continental shelf, like the Salish Sea. In our area the dolphins have been most recently seen near Nanaimo and Howe Sound. They tend to visit in the spring and summer, when food like herring and smelt are more available.

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