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1 What is the marine biome? Marine regions cover about three-fourths of the Earth's surface and include oceans, coral reefs, and estuaries. Marine algae supply much of the world's oxygen supply and take in a huge amount of atmospheric carbon dioxide. The evaporation of the seawater provides rainwater for the land. Reef fish and coral off Eniwetok atoll in the central Pacific. Source: Blue Whale Link to World Book article on blue whales: e+whale

2 Blue Whale Earth's largest animal, the endangered blue whale can eat some 4 to 8 tons (3.6 to 7.3 metric tons) of krill per day. Photograph by Flip Nicklin Map Blue Whale Range Fast Facts Type:

3 Mammal Diet: Carnivore Average life span in the wild: 80 to 90 years Size: 82 to 105 ft (25 to 32 m) Weight: Up to 200 tons (181,437 kg) Group name: Pod Protection status: Endangered Did you know? When a blue whale exhales, the spray from its blowhole can reach nearly 30 ft (9m) into the air. Size relative to a bus: Blue whales are the largest animals ever known to have lived on Earth. These magnificent marine mammals rule the oceans at up to 100 feet (30 meters) long and upwards of 200 tons (181 metric tons). Their tongues alone can weigh as much as an elephant. Their hearts, as much as an automobile. Blue whales reach these mind-boggling dimensions on a diet composed nearly exclusively of tiny shrimplike animals called krill. During certain times of the year, a single adult blue whale consumes about 4 tons (3.6 metric tons) of krill a day. Blue whales are baleen whales, which means they have fringed plates of fingernail-like material, called baleen, attached to their upper jaws. The giant animals feed by first gulping an enormous mouthful of water, expanding the pleated skin on their throat and belly to take it in. Then the whale's massive tongue forces the water out through the thin, overlapping baleen plates. Thousands of krill are left behind and then swallowed. Blue whales look true blue underwater, but on the surface their coloring is more a mottled bluegray. Their underbellies take on a yellowish hue from the millions of microorganisms that take

4 up residence in their skin. The blue whale has a broad, flat head and a long, tapered body that ends in wide, triangular flukes. Blue whales live in all the world's oceans occasionally swimming in small groups but usually alone or in pairs. They often spend summers feeding in polar waters and undertake lengthy migrations towards the Equator as winter arrives. These graceful swimmers cruise the ocean at more than five miles an hour (eight kilometers an hour), but accelerate to more than 20 miles an hour (32 kilometers an hour) when they are agitated. Blue whales are among the loudest animals on the planet. They emit a series of pulses, groans, and moans, and it s thought that, in good conditions, blue whales can hear each other up to 1,000 miles (1,600 kilometers) away. Scientists think they use these vocalizations not only to communicate, but, along with their excellent hearing, to sonar-navigate the lightless ocean depths. Really Big Babies Blue whale calves enter the world already ranking among the planet's largest creatures. After about a year inside its mother's womb, a baby blue whale emerges weighing up to 3 tons (2.7 metric tons) and stretching to 25 feet (8 meters). It gorges on nothing but mother's milk and gains about 200 pounds (91 kilograms) every day for its first year. Blue whales are among Earth's longest-lived animals. Scientists have discovered that by counting the layers of a deceased whale's waxlike earplugs, they can get a close estimate of the animal's age. The oldest blue whale found using this method was determined to be around 110 years old. Average lifespan is estimated at around 80 to 90 years. Between 10,000 and 25,000 blue whales are believed to still swim the world's oceans. Aggressive hunting in the 1900s by whalers seeking whale oil drove them to the brink of extinction. Between 1900 and the mid-1960s, some 360,000 blue whales were slaughtered. They finally came under protection with the 1966 International Whaling Commission, but they've managed only a minor recovery since then. Blue whales have few predators but are known to fall victim to attacks by sharks and killer whales, and many are injured or die each year from impacts with large ships. Blue whales are currently classified as endangered on the World Conservation Union (IUCN) Red List. Source: Click on this link to an interactive activity about the size and behavior of the blue whale:

5 Click this link for a video story about blue whales off Los Angeles. What do you think about boats going so close to the whales? Source: US:official&biw=971&bih=556&tbm=isch&tbnid=NwLF7BBGkudxTM:&imgrefurl= 65&hovw=306&tx=225&ty=83&sig= &page=1&tbnh=80&tbnw=149&start=0&ndsp=15&ved=1t:429,r:9,s:0,i:86ß Blue whales dine in treacherous waters off L.A.'s coast Endangered blue whales, because they increasingly feed near the ports of Los Angeles and Long Beach, are at risk of being hit and killed by the enormous ships heading to and from the complex. October 07, 2011 By Tony Barboza, Los Angeles Time The waters near the nation's largest port complex have become a bustling feeding ground for increasing numbers of blue whales, putting the endangered animals at greater risk of being hit

6 and killed by the enormous ships moving in and out of the harbor, according to researchers who've been tracking them for nearly two years. The whales, which migrate along the coast of California and are regularly spotted from May to December, are congregating in such numbers in the midst of this virtual freeway of ship traffic that the spot has become "the area of densest concentration close to shore in all of California," said research scientist John Calambokidis. Daily appearances by the world's largest animal feeding along an underwater drop-off outside Los Angeles Harbor have been a huge draw for sightseers. But the underwater buffet of krill, the shrimp-like crustaceans the whales feast on, is in the path of a major shipping lane and puts them in danger of being hit and killed by vessels leaving the port. "While this is a unique and exciting opportunity to have these animals out here, it also puts them at great risk," said Calambokidis, co-founder of the Olympia, Wash.-based Cascadia Research Collective. Over the last decade, dozens of whales off the California coast have been injured or killed by ships, and scientists think the slowly recovering population of about 2,500 West Coast blue whales is especially vulnerable. Four blue whales were struck and killed by vessels in 2007 near the Channel Islands National Marine Sanctuary off the coast of Santa Barbara, raising the alarm of federal wildlife officials, who now monitor the whales from the air and use their coordinates to issue notices asking freighters to voluntarily slow down. With the increase in blue whales near the Los Angeles-Long Beach port complex, Calambokidis said, "now we're worried about here." For two years, Calambokidis has headed the project to photograph, tag and keep tabs on whales that feed near the shipping lanes. Interns for the Aquarium of the Pacific accompany tourists aboard twice-a-day whale watching trips by Harbor Breeze Cruises to photograph and mark coordinates of the few dozen blue whales that have taken to grazing about 5 miles off the Los Angeles coast. As part of the ongoing work to track the whales' movements through the busy waters off Long Beach, researchers in an inflatable motorboat approach a whale and use a long pole to press a shoe-sized transmitter equipped with a suction cup to its back as it surfaces. The bright orange transmitters are designed to fall off after less than 24 hours. An 80-foot whale whose tag was scooped from the ocean Tuesday is a regular visitor that has been in the area for about a month. When researchers tagged the same whale a week before, they downloaded data that revealed a typical behavior pattern. The animal spent most of the day just outside the port, diving as deep

7 as 1,000 feet. After dark, it stayed near the surface, perhaps to rest, and swam to the Santa Monica Bay. The tag was eventually recovered in the South Bay. The GPS tracking device records the whale's coordinates each time it surfaces, measures how deep it dives and how it reacts to passing ships. Some are equipped with acoustic sensors that record the animals' low-frequency calls and the rumble of passing freighters. The information collected so far has uncovered a disturbing pattern: At night, the whales spend twice as much time lingering near the surface, where they are most vulnerable to being hit by ships. And they show no sign of trying to avoid approaching container ships. For reasons that are not yet understood, the whales often draw closer to the vessels, increasing the odds of a collision. A better understanding of the whales' behavior in busy waters could help authorities decide how to separate them from ship traffic. Ocean carriers are backing a proposal to alter shipping routes to avoid whale feeding grounds, while conservation groups have petitioned the Obama administration for a speed limit through California's national marine sanctuaries. Later on the research trip Tuesday, Calambokidis spotted a group of whales surfacing to breathe as a fully-loaded cargo ship cruised by. "These whales are in the outbound shipping lane," he said. Among them was the regular the same whale they had just retrieved the tracking device from. He can recognize the individual by its skinny dorsal fin and unique pattern of dark blotches, markings that are like fingerprints but even more detailed. It's not surprising the abundant food has the creature coming back again and again. "They're constantly in this mode of looking for a place to feed," Calambokidis said. "So when they find a patch of prey, they stick around for a while." tony.barboza@latimes.com

8 Source: US:official&biw=971&bih=556&tbm=isch&tbnid=axN2iHfb0DK7cM:&imgrefurl= EmtmWM&imgurl= infographic.jpg&w=600&h=600&ei=erwnt- GlMImgiAKa8JCsCA&zoom=1&iact=hc&vpx=285&vpy=203&dur=115&hovh=225&hovw=225&tx=147&ty=124&sig= &p age=9&tbnh=158&tbnw=158&ndsp=13&ved=1t:429,r:1,s:101,i:35

9 Blue whales keep getting bigger Tuesday, 31 January 2012 Anna Salleh ABC It's easier to grow bigger in the sea with the water holding up your weight, say researchers (Source: Don Shapiro/iStockphoto) Blue whales are the largest animal to have ever lived on Earth and - for now - are continuing to get bigger, say researchers. The findings come out of a study by evolutionary biologist Dr Alistair Evans, of Monash University in Melbourne, and colleagues. "The biggest animal ever is potentially still getting bigger," says Evans, whose study is reported this week in Proceedings of the Royal Academy of Sciences. When the dinosaurs and their marine cousins went extinct 65 million years ago, mammals took the opportunity to take advantage of the space these creatures had previously occupied, says Evans. He and colleagues investigated the increase in the size of mammals since this time. The study estimated the body size of hundreds of species in 28 different orders of animals in 20 time periods over the past 70 million years. The researchers used teeth, skulls and limb bones to work out the size of the animal, based on comparisons with current day species. The researchers found it took whales 5 million generations, or 30 million years, to go from 25 kilograms to 190 tonnes - the weight of a blue whale. By contrast land mammals got bigger at half the rate of marine mammals.

10 For example, it took 10 million generations for a mammal to get 5000 times bigger, and over twice as long to evolve form the size of a mouse to the size of elephant. Elephants have been the largest land animal for the past 10 million years, and before that the record was held by a now-extinct rhino-like animal, says Evans. The researchers believe one reason for this faster evolution in size among marine animals is that it's easier to grow bigger in the sea. With the water holding you up, fewer body modifications are required to handle the increase in weight. Whales getting bigger Interestingly the new study found that almost all mammals are smaller today than they were in the last major ice ages - a million or so years ago. Evans says this may be because the biggest animals have been hunted to extinction, or because the weather is warmer and there is less advantage to being big. But the blue whales are an exception, he says. "It's continued to get bigger," says Evans. He says ocean currents boosting the amount of krill around the Antarctica are likely to be responsible for this growth. Co-author zoologist Dr Erich Fitzgerald of Museum Victoria says whales in general have continued to get larger and could theoretically continue to grow assuming they could get the food they require. But he says the future is uncertain given such things as overfishing, which threatens whales' food source. "Their maximum size may be peaking during our lifetime," says Fitzgerald. Why get bigger? Evans says there are certain advantages to increasing in size. For example, your relative metabolic rate decreases with size which means you don't have to eat as much food per gram of your own tissue. "It's more efficient to be big," he says. This means you can eat more abundant low energy-dense foods, like trees, leaves and grass. And you can avoid being eaten by other animals, can store more energy and can travel further distances. Small animals by contrast have a high metabolic rate and need to eat insects, seeds and fruit, which are less available.

11 But not all mammals got larger after the demise of the dinosaurs. Some, especially those isolated on islands, got smaller - including now extinct dwarf mammoths off the coast of California and dwarf elephants in the Mediterranean. Getting smaller can have advantages too, adds Evans, including helping animals to adapt to a smaller food resource. Interestingly, these animals evolved smaller size much faster than those evolving larger size, the researchers found. Source: Dead Blue Whale off California Coast, 2007 Source:

12 Sorce: US:official&biw=971&bih=556&tbm=isch&tbnid=QXX7e1nBYU6DgM:&imgrefurl= bluewhale.htm&docid=_pcvyeknkviqkm&imgurl= rint- 2pH6WyiQLv4sGjCA&zoom=1&iact=hc&vpx=554&vpy=142&dur=3090&hovh=183&hovw=275&tx=166&ty=106&sig= &page=1&tbnh=108&tbnw=154&start=0&ndsp=15&ved=1t:429,r:3,s:0,i:73