Category Zoology

Sea anemones are known for their beauty; with their spectacular white, green, blue or red patterns and circles of petal-like tentacles, sea anemones have the appearance of harmless underwater flowers. It is with this appearance that they manage to deceive a lot of marine creatures.

More than 1,000 sea anemone species are found throughout the world’s oceans at various depths in varying sizes- some are as small as half an inch, while others may grow up to a size of six feet! Warmer seas are home to the largest and most colourful sea anemones.

Sea anemones are close relatives of jellyfish and corals. They do not have a solid skeleton. Some species have adhesive-secreting structures and cover themselves with grains of sand, bits of shell, or other foreign objects. With their elastic bodies and venomous tentacles, they trap a range of marine creatures including small fish, shrimps and crabs.

Do you know what a siphonophore is? It is an animal made up of a colony of organisms working together. The Portuguese man-of-war is a colony of individual organisms called polyps. It is often mistaken for a jellyfish, but truth be told, it is a highly venomous open ocean predator. It typically feeds on small marine organisms, such as fish and plankton.

Each polyp that makes up a Portuguese man-of-war is intertwined with the others, has highly specialized functions and cannot survive without the others. The largest of the polyps is known as the float; it is a bag of secreted gas which keeps the colony afloat. There are also feeding polyps, which are small digestive bags, each with its own mouth.

Tentacle polyps are the ones that look like elongated threads below the float and are studded with stinging cells. They have numerous venomous microscopic nematocysts which deliver a painful sting powerful enough to kill fish. They use the sting against predators as well. Apart from these, there are reproductive individuals as well.

Sea otters inhabit the Pacific coast. These sleek, furry marine mammals have no insulating layer of fat like other animals that live in colder climates, but are kept warm by their fur and high metabolism.

Sea otters were hunted for their fur to the point of near extinction. In fact, sea otters have the densest fur of any mammal; the coat of a sea otter has over half a million hairs per 6.5 square centimeters! These animals are very clean as well; they wash themselves after eating and frequently clean their fur with paws.

The way sea otters eat is interesting; they use their stomach as a table. A sea otter eats in the water, lying on its back, with its food on its chest. Sea otters are the only otters to give birth in the water. Mother sea otters have the ability to nurture their young while floating on their backs.

Sea otters play an instrumental role in controlling sea urchin populations which would otherwise inflict extensive damage to kelp forest ecosystems (underwater forests).

The humpback whale is an enormous creature; it is as big as a school bus! It is known both for the howling sounds it makes and the amazing acrobatic abilities.

Humpbacks feed primarily in summer and live off their fat reserves during winter. They use many innovative methods for feeding. One such method is called bubble net feeding.

A group of whales will swim in a shrinking circle blowing bubbles below a school of prey. The shrinking ring of bubbles will encircle the school and confine it in an ever-smaller cylinder. This way, they can swallow thousands of fish in a single gulp.

Mother humpbacks swim close to their young ones, often touching one another with their flippers. Humpbacks roam all over the world and the place where they could be located depends on the time of the year.

The walrus has a unique look with a long tusk and a moustache. It is usually found in the Arctic Circle, basking along with its companions. Though it is extremely sociable and playful, a walrus can be really aggressive during the mating season.

The diet of a walrus usually consists of clams and mussels. It occasionally includes fish and even small seals. It roots along the ocean floor with its tusk and identifies its prey with its whiskers.

The walrus has an iconic tusk which it uses for a variety of reasons. It is used to haul its enormous body out of frigid waters, and to break breathing holes into ice from below. But it is not used to dig up food.

Walruses usually live in large groups numbering up to a hundred and above. They occupy the coasts and margins of ice shelves, where they periodically haul themselves onto beaches and ice floes to rest and bask.

Sea lions are relatives of seals and walruses. They can be distinguished by their external ear flaps, long fore-flippers, short, thick hair, and a big chest and belly. Their strong flippers and streamlined body make them well-adapted to the aquatic way of life.

California sea lions are known for their intelligence, playfulness, and noisy barking. Keeping their playfulness aside, they are skilled hunters – they can hunt continuously for up to 30 hours!

California sea lions are also known to cooperate with other predators like dolphins while hunting large schools of fish. They prey on a wide variety of seafood, mainly squid and fish, and sometimes clam. The fish and squid species they commonly eat include salmon, hake, Pacific whiting, anchovy, herring, rockfish, lamprey, dogfish, and market squid. Depending on how much food is available, they either eat alone or in groups.

California sea lions aren’t normally dangerous to humans, and attacks are uncommon, but they are large and unpredictable wild animals with sharp teeth; so it’s better to maintain a healthy distance!