GIANT LIVES
Chapter One
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GIANT LIVES
BLUE WHALE
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BLUE WHALE
Balaenoptera musculus
Only in the vastness of the ocean could there live the largest creature on earth. The blue whale. Before commercial whaling 300,00 blue whales cruised the oceans. Today less than 10,000 remain. We know almost nothing of their lives and for years assumed that like the other great whales they migrated to cold rich seas to feed. Blue whales are the largest animals ever to have lived, bigger even than the largest of the dinosaurs. These jumbo-jet-sized giants inhabit the open ocean, where they are found most frequently along the continental shelf edges and near polar ice. They are so big that a blue whale’s blood vessels are wide enough for a human to swim through. A single calf is produced every two to three years, and from birth each calf consumes up to 50 gallons of milk every single day, leading to a colossal weight gain
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of 90 kilograms per day in its first year of life. Blue whales are not easy to approach like southern right whales and not friendly like humpback whales. They are elusive and perfectly streamlined blues are one of the fastest ocean giants powering along at over 30 miles an hour. The largest creature in the ocean feeds almost exclusively on one of the smallest, krill. A crustacean just a few inches long Krill are normally found in cold polar seas. Recently Scientists have discovered that along the Sri Lanken coastline unusual condiitions allow kirll to thrive in tropical waters. The upwelling of cold nutrient-rich water is unusual for the tropics but appears to contain the perfect food for blue whales. The Indian Ocean blue whales are unique as they live there all year round.
The Blue Whale is the largest animal that has ever lived on planet Earth
BLUE WHALE
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The blue whales feed by diving deep down and find dense patches of krill and lunge-feed through them. They dive to 600 feet below where the krill are hiding in the gloom. The whale then powers up through the swarm gulping its own body weight of water into its ballooning throat It then strains out the nutritious krill through its fine mesh of baleen. Each lunge requires huge effort but if you have a mouth as big as a blue whale’s you can catch so much food that the whole process becomes extraordinarily efficient. Their size is the secret of their success. Pumped up on tonnes of krill blue whales can grow as long as a jetliner weighing almost 200 tonnes twice the size of the largest dinosaur. Worryingly the blue’s giant size and its giant appetite are now putting it at risk. We know that climate change is occurring and that in places like Antarctica the temperatures have sky-rocketed. We also know that krill has started to decrease and when you don’t have enough food blue whales are going to have trouble surviving
So as climate change happens as krill starts to be depleted blue-whale survival could be in jeopardy. Blue whales are still endangered but they are recovering slowly For their recovery to continue it’s not just the whales themselves that will need protection. For their recovery to continue it’s not just the whales themselves that will need protection but the seas and the other creatures they depend on. We may have missed the chance to live with the great dinosaurs of the past but we do have the good fortune to be sharing our time with the largest creatures that ever lived these magnificent ocean giants
Blue whale
Length - 32 m Wieght - 200 Tons (Max.) Type - Baleen LIfe span - 80~90 years Food - Krill
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BLUE WHALE
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32m
15m
12m
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15m
12m
12m
BLUE WHALE
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SOUTHERN RIGHT WALES Eubalaena australis
A southern right whale’s head measures one third of its total length. It is one of the easiest whales to identify as the enormous head is also covered in white-coloured outgrowths of tough skin. These callosities form a unique pattern on each whale, like fingerprints in humans. Courtship and mating is both tender and graceful, without any animosity between males mating with the same female. Females calve once every three years, giving birth to a weighty 1,500kg calf. Despite their great size, the young are brought up on a diet of high-fat milk and remain in shallow waters, safe from the likes of orcas and great white sharks. Southern right whales are only found in the oceans of the southern hemisphere. They inhabit waters close to Antarctica during the summer and migrate northwards to coastal areas in winter. Male southern right whales have the largest sexual organs of any animal. Their testicles can weigh up to one tonne and their penises can measure over 2.5m. Scientists have linked these proportions to increased sperm competition in the species in which mating is described as an “orgy”
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BLUE WHALE
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BLUE WHALE
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BOWHEAD WHALE Balaena mysticetus
Within the Arctic Circle lives a whale three times the size of a grey whale, It’s a bowhead whale named after its enormous curved upper jaw. It’s grown to massive size for even more extraordinary reasons as it stays in the Arctic all year round it doesn’t need to be big to survive lengthy migrations and protected by the maze of shifting pack ice it has less to fear from killer whales. So why is this whale so big?
In eastern Greenland a scientific teams are attempting to unlock the secrets of this little-known giant. In the last two centuries bowheads were almost wiped out by commercial whalers and are notoriously wary of humans and are remarkably alert to danger. During the winter bowheads are impossible to track but in spring they announce their presence with song. Scientists think that these are mating calls and that the bowheads may gather
These whales are the fattest animals on the planet
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GIANT LIVES
BOW HEAD
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to breed. Bowheads are the masters of concealment able to hold their breath for up to an hour and a half The bowheads survive this cold through being a giant. The bigger and rounder the body the better it is at retaining heat. Wrapped in 50 tonnes of insulating blubber these whales are the fattest animals on the planet. Half their entire body weight is fat! The bowhead whale is second only in size to the mighty blue whale. Its enormous bow-shaped mouth, the largest mouth of any animal, contains a baleen measuring three metres. The 300 plates filter out the tiny crustaceans from the water which make up its diet. The bowhead whale inhabits cold Arctic waters and so needs the best insulation. It’s blubber is the thickest found on any animal at half a metre. Female bowheads are perhaps the most flirtatious ocean mammal, constantly teasing the males into a frenzy.
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Length - 20 m Wieght - 100 Tons (Max.) Type - Baleen LIfe span - 150~210 years Food - Copepods
BOW HEAD
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GREY WHALE
Eschrichtius robustus
Grey whales undertake the longest annual migration of any known mammal, along the coastlines between their summer feeding and winter breeding grounds. Belonging to the baleen whale group, they have plates for filtering marine worms and crustaceans from the ocean floor. Grey whales are split into two separate populations, the eastern North Pacific (American) and the critically endangered western North Pacific (Asian) population. They are the only species in their genus, which in turn, is the only genus in the family. Grey whales undertake the longest annual migration of any known mammal, travelling from warm breeding grounds at the equator to their summer feeding grounds in the Arctic. Researchers have suggested that these epic journeys could also be driven by the threat of predation from killer whales. Gray whales are often covered with parasites and other organisms that make their snouts and backs look like a crusty ocean rock. The whale uses its snout to forage by dislodging tiny creatures from the seafloor. It then filters these morsels with its baleen—a comblike strainer of plates in the upper jaw. A piece of gray whale baleen, also called whalebone,
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GIANT LIVES
Length - 15 m Wieght - 40 Tons (Max.) Type - Baleen LIfe span - 50~60 years Food - Amphipods
GREY WHALE
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is about 18 inches (46 centimeters) long and has a consistency much like a fingernail. Whalebone was once used to make ladies’ corsets and umbrella ribs. The gray whale is one of the animal kingdom’s great migrators. Traveling in groups called pods, some of these giants swim 12,430 miles (20,000 kilometers) round-trip from their summer home in Alaskan waters to the warmer waters off the Mexican coast. The whales winter and breed in the shallow southern waters and balmier climate. Other gray whales live in the seas near Korea. Like all whales, gray whales surface to breathe, so migrating groups are often spotted from North America’s west coast. These whales were once the target of extensive hunting, and by early in the 20th century they were in serious danger of extinction.
Grey whales undertake the longest annual migration of any mammal
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GREY WHALE
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