today I feature another wonderful species - WHALES. Believe it or not, one of the few things on my bucket list is to be up close and very personal with some whales - camera at hand of course. Anyway, here is some interesting information on these amazing mammals.
Whales are large, intelligent, aquatic mammals. They breathe air through blowhole(s) into lungs (unlike fish who breathe using gills). Whales have sleek, streamlined bodies that move easily through the water. They are the only mammals, other than manatees (seacows), that live their entire lives in the water, and the only mammals that have adapted to life in the open oceans.
Like all mammals:
- Whales breathe air into lungs,
- Whales have hair (although they have a lot less than land mammals, and have almost none as adults),
- Whales are warm-blooded (they maintain a high body temperature),
- Whales have mammary glands with which they nourish their young,
- Whales have a four-chambered heart.
The biggest whale is the blue whale, which grows to be about 94 feet (29 m) long - the height of a 9-story building. These enormous animals eat about 4 tons of tiny krill each day, obtained by filter feeding through baleen. Adult blue whales have no predators except man.
The smallest whale is the dwarf sperm whale which as an adult is only 8.5 feet (2.6 m) long.
TWO TYPES OF CETACEANS
Cetaceans include the whales, dolphins and porpoises. There are over 75 species of Cetaceans. Whales belong to the order Cetacea (from the Greek word "ketos" which means whale).
SWIMMING AND OTHER WATER ACTIVITIES
Whales have a streamlined shape and almost no hair as adults (it would cause drag while swimming). Killer whales and Shortfin Pilot whales are the fastest, swimming up to 30 miles per hour (48 kph).
Many ceteaceans, especially baleen whales, migrate over very long distances each year. They travel, sometimes in groups (pods), from cold-water feeding grounds to warm-water breeding grounds.
Cetaceans have very strong social ties. The strongest social ties are between mother and calf. A social group of whales is called a pod. Baleen whales travel alone or in small pods. The toothed whales travel in large, sometimes stable pods. The toothed whales frequently hunt their prey in groups, migrate together, and share care of their young. Cetaceans give birth to live young which are nourished with milk from their mothers - they don't lay eggs. Cetaceans breed seasonally, usually in warm tropical waters, and females usually have one calf every 1-3 years. The gestation times range from 9-18 months. Whale calves can swim at or soon after birth. Mother whales care for their young for an extended period of time, usually at least a year, feeding them milk and protecting them.
Complex whales songs can be heard for miles under the water. The humpback's song can last for 30 minutes. Baleen whales sing low-frequency songs; toothed whales emit whistles and clicks that they use for echolocation The songs are thought to be used in attracting mates, to keep track of offspring, and for the toothed whales, to locate prey.
Now, you might like to watch an amazing video, captured by the Great Whale Conservancy. Some guys save the life of a humpback whale that is trapped in fishing net:
Clancy's comment: Truly amazing mammals, eh? Gotta get near them and take hundreds of photographs before I head to the big library in the sky.
Think about this!
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