Humpback Whales
Known for their magical songs, which they sing to communicate with others and to attract potential mates is quite complex and can continue for hours on end. They weigh up to 40 tons and grow anywhere between 48 to 62 feet. Humpback whales migrate annually for feeding as well as breeding. They are omnivore in their dietary habits, feeding on fish, plankton, and tiny shrimp-like krill. They are powerful swimmers; using their tail fin called a fluke to propel and even leap out of water. They are affectionate in their gestures, with mother and calves often swimming close and touching each other with their fins.
Archive for the ‘Sea Creatures’ Category
Whales | Humpback Whales
20
Apr
Whales- Orca Whales
20
Apr
Orca Whales
Most of the times, they hunt together in pods of 40. They often frequent coastal waters, but can also be found in regions close to the Equator. They prey on marine mammals as well fish. They can even grab seals and polar bears right off the ice, using their four inches long teeth. They use a variety of sounds to communicate and each pod is known to have its own typical sound. They have distinctive black-and-white coloring and perform in many aquarium shows.
Whales- Blue Whale
20
Apr
Blue Whale
It is the largest as well as the loudest animal to live on earth. Adult female blue whales are larger than adult males in size. They can grow up to 105 feet long weighing up to 200 tons. Despite their gigantic size, they are shy and placid. They are generally found to be swimming in small groups or pairs. The summers are spent in polar waters and migrate towards the Equator during winters. Their diet mainly composes of nearly 4 tons of krill, tiny shrimp like animals, in a day. They emit a series of sounds to communicate with each other up to 1,000 miles away. Scientists believe they also use these vocalizations to sonar-navigate the ocean depths. They look true blue underwater, but on the surface their coloring is more a mottled blue-grey.
types of whales
19
Apr
The suborder Mysticeti includes the types of whales known as baleen whales and contains four families, which includes the Gray whale, the rorquals, the Right Whales and the Humpback Whale which resides in a genus all it’s own. The largest animal ever to live on the earth, the Blue Whale, is a baleen whale and a member of the group known as rorquals, so called because they have pleated throats. Reaching lengths in excess of 33 metres there are estimated to be only between 6,000 and 14,000 Blue Whales remaining in the oceans of the world, the majority in the southern hemisphere. Baleen whales are filter feeders and largely eat krill (euphausids), copepods and small schooling fish. These types of whales suffered badly at the hands of whalers during the last century and their numbers have been seriously depleted.
Different Types of Whales
Mysticeti
Currently taxonomists divide the mysticetes into the following four families although recently the fact that the Gray Whale stands alone in the family Eschrichtiidae has been challenged.
- Balaenopteridae – Rorquals
- Eschrichtiidae – Gray Whale
- Balaenidae – Right Whales
- Neobalaenidae – Pygmy Right Whale
The suborder Odontoceti, the largest within the order Cetacea, comprises the toothed whales, which includes all dolphins and porpoises. Between them, the ten families contain 36 genera and 70 species, which include Sperm Whales, White Whales, the little known Beaked Whales and Pilot and Killer Whales. The largest Odontocete or toothed whale is the Sperm Whale reaching lengths of 20 metres. An animal of great extremes the Sperm Whale has the largest brain of any animal and probably makes the deepest dive of any whale, possibly up to 3000 metres deep that may last up to two hours in duration. The Sperm Whale is truly global in its coverage and may be found in all oceans of the world.
Odontoceti
- Physeteridae – Sperm Whales
- Kogiidae – Dwarf and Pygmy Sperm Whales
- Monodontidae – White Whales and Narwhal
- Ziphiidae – Beaked Whales and Bottlenose Whales
- Delphinidae – Dolphins, Humpbacked Dolphins, Pilot & Killer Whales
- Plantanistidae, Iniidae, Lipotidae, Pontoporiidae – River Dolphins
- Phocoenidae – Porpoises
Sharks
25
Aug
Sharks
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. They respire with the use of five to seven gill slits. Sharks have a covering of dermal denticles that protect their skin from damage and parasites and improve fluid dynamics so the shark can move faster. They have several sets of replaceable teeth. The earliest known sharks date from more than 420 million years ago, before the time of the dinosaurs.
Intelligence
Contrary to the common wisdom that sharks are instinct-driven “eating machines”, recent studies have indicated that many species possess powerful problem-solving skills, social skills and curiosity. The brain- to body-mass ratios of sharks are similar to mammals and other higher vertebrate species.
In 1987, near Smitswinkle Bay, South Africa, a group of up to seven great white sharks worked together to move a partially beached dead whale to deeper waters to feed.
Sharks can engage in playful activities. Porbeagle sharks have been seen repeatedly rolling in kelp and chasing an individual who trailed a piece of kelp behind it.
Speed
In general, sharks swim (“cruise”) at an average speed of 8 kilometers per hour (5.0 mph) but when feeding or attacking, the average shark can reach speeds upwards of 19 kilometers per hour (12 mph). The shortfin mako may range upwards of 50 kilometers per hour (31 mph). The shortfin mako shark is the fastest shark and one of the fastest fish. The great white shark is also capable of bursts of speed. These exceptions may be due to the “warm-blooded”, or homeothermic, nature of these sharks’ physiology.
Sleep
Some sharks can lie on the bottom while actively pumping water over their gills, but their eyes remain open and actively follow divers. When a shark is resting, it does not use its nares, but rather its spiracles. If a shark tried to use its nares while resting on the ocean floor, it would be sucking up sand rather than water. Many scientists believe this is one of the reasons sharks have spiracles. The spiny dogfish’s spinal cord rather than its brain, coordinates swimming, so it is possible for spiny dogfish to continue to swim while sleeping.
It is also possible that sharks sleep in a manner similar to dolphins, one cerebral hemisphere at a time, thus maintaining some consciousness and cerebral activity at all times.
Teeth
The teeth of sharks are embedded in the gums rather than directly fixed to the jaw, and are constantly replaced throughout the shark’s life. Multiple rows of replacement teeth are grown in a groove on the inside of the jaw and moved forward in a “conveyor belt”; some sharks can lose some 30,000 teeth in their lifetime. The rate of tooth replacement varies from once every 8–10 days to several months. In most species teeth are replaced one at a time, while in the cookie-cutter sharks the entire row of teeth is replaced simultaneously.
The shape of a shark’s tooth depends on its diet: those that feed on mollusks and crustaceans have dense flattened teeth for crushing, those that feed on fish have needle-like teeth for gripping, and those that feed on larger prey such as mammals have pointed lower teeth for gripping and triangular upper teeth with serrated edges for cutting. The teeth of plankton-feeders such as the basking shark are greatly reduced and non-functional.
Types of Sharks
Types of shark teeth
Some sharks can lie on the bottom while actively pumping water over their gills, but their eyes remain open and actively follow divers.[44] When a shark is resting, it does not use its nares, but rather its spiracles. If a shark tried to use its nares while resting on the ocean floor, it would be sucking up sand rather than water. Many scientists believe this is one of the reasons sharks have spiracles. The spiny dogfish‘s spinal cord rather than its brain, coordinates swimming, so it is possible for spiny dogfish to continue to swim while sleeping.[44]
It is also possible that sharks sleep in a manner similar to dolphins,[44] one cerebral hemisphere at a time, thus maintaining some consciousness and cerebral activity at all times.
