GRAY WHALE (Eschrichtius robustus)

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1 GRAY WHALE (Eschrichtius robustus) Description: The Gray whale has a streamlined body, with a narrow tapered head. As a baleen whale, it has a series of fringed overlapping plates hanging from each side of the upper jaw, where teeth might otherwise be located. The upper jaw is dimpled and each of the little depressions contains one stiff hair. There are two to five long grooves on the ventral throat that allow it to expand as the whale feeds. Color: The gray whale received its name from the gray patches and white mottling on its dark skin. On the skin are many scratches, scattered patches of white barnacles, and orange whale lice. New born calves are dark grey to black, although some may have distinctive white markings. Fins and fluke: The gray whale has no dorsal fin. About two-thirds of the way back on its body, is a prominent dorsal hump followed by a series of six to twelve knuckles along the dorsal ridge. Its flippers are paddle-shaped and pointed at the tips. Its fluke is about ten to twelve feet across and deeply notched in the center. Size: Adult males measure 45 to 46 feet and adult females measure slightly more. Both sexes weigh 30 to 40 tons. Feeding: This baleen whale feeds on small crustaceans such as amphipods, and tube worms found in bottom sediments. When feeding on the bottom this whale lies on its side and sucks in sand and/ or mud, leaving a large pit. Mating and Breeding: Gray whales reach sexual maturity at 5 to 11 years of age, or when they reach 36 to 39 feet in length. Gestation is 12 to 13 months. The calf weighs 1100 to 1500 pounds and is about 15 feet long. Calves nurse 7 to 8 months on milk that is around 50% fat. Females bear a single calf at intervals of 2 or more years. Distribution and Migration: Gray whales inhabit shallow coastal waters of the eastern North Pacific. They make one of the longest of all mammalian migrations, averaging 10,000 to 14,000 miles. Southbound Gray whales may be seen near the Piedras Blancas Rookery from December through February and traveling northbound from February through May. Cows with calves are seen mainly in April and May. Natural History: Typically gray whales blow 4 to 6 times per minute between dives of 3 to 5 minutes but can stay submerged up to 15 minutes. They travel at 3 to 6 miles per hour. Status: Hunted to the edge of extinction in the 1850's and again in the early 1900s the north Pacific gray whale population has made a remarkable recovery since being protected in It now numbers between 19,000 and 23,000, probably close to their original population. Gray whales were known as devilfish because of their fighting behavior when defending themselves from whalers.

2 THE HUMPBACK WHALE (Megaptera novaeangliae) Description: The head of a humpback whale is broad and rounded when viewed from above, but slim in profile. The body is quite round, narrowing to a slender peduncle (tail stock). The top of the head and the lower jaw have rounded bump-like knobs, each containing at least one stiff hair. The purpose of these hairs is not known, though they may allow the whale to detect movement in nearby waters. There are between 20 and 50 ventral grooves which extend slightly beyond the navel. Color: The body is black on the dorsal (upper) side, and mottled black and white on the ventral (under) side. The color pattern extends to the flukes. When the humpback whale "sounds" (goes into a long or deep dive) it usually throws its flukes upward, exposing the black and white patterned underside. This pattern is distinctive to each whale. The flippers range from all white to all black dorsally, but are usually white ventrally. Fins and Fluke: About 2/3 of the way back on the body is an irregularly shaped dorsal (top) fin. Its flippers are very long, between 1/4 and 1/3 the length of its body, and have large knobs on the leading edge. The flukes (tail), which can be 18 feet wide, are serrated and pointed at the tips. Size: Adult males measure 40 to 48 feet; adult females measure feet. They weigh 25 to 40 tons. Feeding: Humpback whales feed on krill and various kinds of small fish. Each whale eats up to 1-1/2 tons of food a day. As a baleen whale it has a series of fringed overlapping plates hanging from each side of the upper jaw where teeth might otherwise be located. These plates consist of a fingernail-like material called keratin that frays out into fine hairs on the ends inside the mouth near the tongue. The plates are black and measure about 30 inches in length. During feeding, large volumes of water and food can be taken into the mouth because the pleated grooves in the throat expand. As the mouth closes water is expelled through the baleen plates, which trap the food on the inside near the tongue to be swallowed. Mating and Breeding: Humpback whales reach sexual maturity at 6-10 years of age or when males reach the length of 35 feet and females reach 40 feet. Each female typically bears a calf every 2-3 years. Gestation is 12 months. A calf is between feet long at birth and weighs up to a ton. It nurses on the mother s rich milk which has 45-60% fat content. The calf is weaned to solid food when it is about a year old. Distribution and Migration: Found in all the world's oceans. Migration is southbound in November and northbound in the spring. Natural History: Male humpback whales, as part of mating behavior, sing long, complex songs. A typical song lasts from 10 to 20 minutes, is repeated continually for hours at a time, and changes gradually from year to year. Status: Because their feeding, mating and calving grounds are close to shore, and because they are slow swimmers, these whales were an easy target for early whalers. The IWC gave them worldwide protection in It is believed they number 30,000 to 40,000 at present, or about 30 to 35% of the original population.

3 THE ORCA (KILLER WHALE) (Orcinus orca) Description: The orca is a stout, streamlined animal. It has a round head that is tapered, with an indistinct beak and straight mouth-line. Color: The orca has a striking color pattern made up of well defined areas of shiny black and white. The dorsal (top) part of its body is black, with a pale white "saddle" behind the dorsal fin. It has an oval, white eye patch behind and above each eye. The chin, throat, central length of the ventral (underside) area and undersides of the tail flukes are white. Each whale can be individually identified by its markings and by the shape of its saddle patch and dorsal fin. Fins and Fluke: The dorsal fin is a distinctive feature which can reach 6 feet high in males and is shaped like an isosceles triangle. The immature male and the female dorsal fins are also large, reaching 3 feet high but are falcate (curved). The paddle-shape pectoral flippers are broad, and can reach a length of nearly 6 feet and a width of 3 feet. Size: Males can grow as large as 32 feet long and weigh 8 to 9 tons. Females can reach 23 feet in length and weigh up to 4 tons. Feeding: The mouth of the orca is large and well adapted for hunting. It has 46 to 50 conicalshaped teeth that point slightly backwards and inward. The upper and lower teeth interlock, which aids in gripping large prey and tearing it into smaller pieces for swallowing. Orcas feed on a variety of animals including: sea lions, elephant seals, harbor seals, porpoises, squid, sharks, fish, penguins, smaller whales such as belugas and narwhales and even large baleen whales, such as gray whales. Mating and Breeding: Orcas become sexually mature between the ages of 10 and 18. Newborn calves have been observed throughout the year suggesting that mating can occur at any time with no particular breeding season. The gestation period is estimated to be between 13 and 17 months. At birth, a calf is generally 6 to 7 feet long and weighs around 400 pounds. Distribution and Migration: The orcas are found in all oceans of the world though they are more abundant in cooler waters. They seem to travel according to the availability of food and move freely from hemisphere to hemisphere. Natural History: Generally Orcas spend their lives in cooperative, tightly structured family groups called pods. These pods persist for generations, developing their own dialects of squeals and moans. Members of the pod hunt together, defend their young and assist sick or injured members. Other pods have much less structure and more fluid membership. Status: Although orcas are widely distributed, total world population is still unknown. They have no natural enemies and have not been hunted as much as other whales.

4 COMMON DOLPHIN (Delphinus delphis) Description: The color patterns are the most elaborate of any cetacean. The back is dark gray to black from the top of the head to the tail dipping to a V on the sides below the dorsal fin. The flanks are light gray behind the dorsal fin and yellowish-tan toward the dorsal fin, forming an hourglass pattern. Its belly is white. There are large dark circles around the eyes connected by a dark line that runs across the head behind the beak and a black stripe runs from the jaw to the flippers. This is the classic dolphin of Greek and Roman mythology. Fins and Fluke: The dorsal fin is triangular-to-falcate (curved). It is pointed and located near the middle of the back and is black to light gray in color with a black border. The flippers are long and thin and slightly curved or pointed depending on geographic location. Flukes are thin and pointed at the tips with a slight notch in the center. Size: Common dolphins can reach lengths of 7.5 to 8.5 feet and weigh as much as 300 pounds. Feeding: Common dolphins feed on squid and small schooling fish. They have been seen working together to herd fish into tight balls. Like many other dolphin species, the common dolphin will sometimes take advantage of human fishing activities (such as trawling), feeding on fish escaping from the nets or discarded by the fishermen. Mating and Breeding: Sexual maturity is reached at 3 to 4 years of age or when they reach 6 to 7 feet in length. Calves are 30 to 34 inches at birth; gestation period is 10 to 11 months. Distribution and Migration: The common dolphin is found in all tropical waters and can be seen off our coast in late summer. Natural History: Common dolphins are often found in large herds of hundreds or even thousands. They are extremely active, fast moving, and engage in spectacular aerial behavior. They are noted for riding bow and stern waves of boats. Status: Hundreds of thousands of common dolphins have been taken in purse seine nets used by tuna fishing operations, but the species is not considered threatened.

5 PACIFIC WHITE-SIDED DOLPHIN (Lagenorhynchus obliquidens) Description: The Pacific white-sided dolphin has a short, rounded, thick beak containing 23 to 32 small, rounded slightly curved teeth in each side of the upper and lower jaws. This dolphin is energetic and quite active and is frequently seen leaping, belly flopping, and somersaulting. It is a strong and fast swimmer and enthusiastic bow rider, often staying with moving vessels for extended periods. Color: The Pacific white-sided dolphin is attractively marked. Its back is black and its sides are light gray with thin, white stripes that extend from above the eye along the sides, widening towards the tail; its belly is white. It has a black beak and lips and a black ring around each eye. Fins and fluke: Its dorsal fin is tall and sharply hooked, and is located at the center of the back. The leading edge is black and the rear portion is light gray. Its flippers are small and curved and rounded at the tips. It flukes are notched in the center. Size: These dolphins reach a length of 7 to 8 feet and can weigh 300 pounds. Feeding: It eats squid and small schooling fish such as anchovies, herring, sardines, and hake. It is believed to feed largely at night. Mating and Breeding: Sexual maturity for both sexes is reached when they are 6 feet in length. Length at birth is 31 to 37 inches; gestation period is estimated to be 9 to 12 months. Distribution and Migration: The Pacific white-sided dolphin inhabits temperate, coastal waters in the North Pacific, avoiding tropical or Arctic waters. Its range extends from the Aleutians to the tip of Baja California. They are very common year round residents in our area. Natural History: They are often found in large herds of 90 to 100. The herds are made up of both sexes and all ages. Status: This species is no longer commercially hunted in the United State. Population figures are unknown. They are often referred to as "lag" because of its cumbersome scientific name.

6 BOTTLENOSE DOLPHIN (Tursiops truncatus) Description: This is a relatively robust dolphin with a short and stubby beak hence the name bottlenose. The bottlenose dolphin (like the beluga) has more flexibility in its neck than other oceanic dolphins, because 5 of the 7 neck vertebrae are not fused together as in other oceanic dolphins. There are pairs of sharp, conical teeth in each side of its jaw. Color: The color of the bottlenose dolphin varies considerably, but generally this dolphin is light gray to slate gray on the upper part of the body shading to lighter sides and pale, pinkish gray on the belly. Fins and fluke: The dorsal fin is high and falcate (curved) and located near the middle of the back. The flukes are broad and curved with a deep median notch. The flippers are of moderate length and pointed. Size: Adult length is from 8-12 feet. These dolphins may weigh as much as 1,100 pounds. Males are significantly larger than females. Feeding: Feeding behaviors are diverse, sometimes involving coordinated efforts to catch food, feeding in association with human fishing, and chasing fish into mud banks. An adult bottlenose dolphin may consume pounds of food each day. They will eat primarily fishes, and sometimes squid, and crustaceans. Mating and Breeding: Males reach sexual maturity at about 10 years. Females reach sexual maturity between 5-10 years. The gestation period is 12 months. Calving takes place year round with peaks during the spring and fall. Calves nurse for over a year and stay with their mothers for 3-6 years. Distribution and Migration: They are found worldwide in temperate and tropical waters, absent only from 45 degrees pole-ward in either hemisphere. In some areas, dolphins have limited home ranges; in others, they are migratory. Natural History: They live in relatively open societies. Mother and calf bonds and some other associations appear to be strong. Status: Protected by the Marine Mammal Protection Act, the bottlenose dolphins are still generally plentiful in numbers off our coast; however they are near depletion in some areas of the world. Bottlenose dolphins are accidently caught in a variety of fishing gear and they are very vulnerable to pollution, habitat alteration, collisions with boats, and other disturbances.

7 HARBOR PORPOISE (Phocaena phocoena) Description: The body of the harbor porpoise is small in size, but rotund and stocky through the mid-section, tapering to a slender tailstock. Its snout is blunt and rounded without a prominent beak. Its mouth is small and tilts upward, and contains 22 to 28 small, spade shaped teeth on each side of the upper jaw and 22 to 26 on each side of the lower jaw. Ancient Romans called them porcus piscus or pigfish. Our word porpoise comes from this. Color: Its back is very dark gray or dark brown, shading to a lighter gray patch on the sides; its belly is white. Its flippers are also dark in color, and a dark stripe extends from the flipper to the eye. Fins and fluke: Flippers are small, rounded at the tips, and oval in shape. The dorsal fin is broad based, low, and triangular and is located slightly aft of the center of the body. Sometimes a series of nodules are found on the leading edge of the dorsal fin. Its flukes are small and curved with a definite median notch. Size: Maximum length is 6 feet with a possible maximum weight of 200 pounds. Most harbor porpoises are much smaller, and do not exceed 5 feet or weigh more than 130 pounds. The females are slightly larger than the males. Feeding: The harbor porpoise eats non-spiny fish such as herring, cod, whiting, squid, Pollock, and sardines. It seems to require large amounts of food, consuming approximately 10% of its body weight each day. Mating and Breeding: Sexual maturity is believed to be at 3 to 4 years. Calves are 27 to 35 inches at birth and weigh 14 to 22 pounds. Gestation period is about 11 months, and the calving interval is usually every 2 years. Calves may nurse for about 8 months. Distribution and Migration: This is an inshore species inhabiting shallow, coastal waters. Harbor porpoises are common in our area. Natural History: Harbor porpoises may be seen singly or in pairs, or in small groups of 6 to 10 animals. Status: The harbor porpoise has been hunted for centuries. Though still locally abundant, they are not as numerous as they once were.

8 DALL'S PORPOISE (Phocoenoides dalli) Description: Dall s porpoise has an extremely robust and muscular body, especially through the mid-section, and the male is considerably thicker than the female. Its head is very small and rounded. The head slopes steeply to a short poorly defined beak. Its mouth is small and narrow, with 19 to 23 very small spade-shaped teeth in each side of the upper jaw and about 20 to 24 teeth in each side of the lower jaw. The teeth of Dall s porpoise are most unusual. Each tooth is separated by rigid, protruding growths called gum teeth. These horny growths help in grasping slippery food. Color: Dall s porpoise is black with white markings. Though the color pattern varies, most are basically black on the upper portions of the body, with large, oval-shaped white sides and white bellies. A band of white borders the flukes and the dorsal fin is usually patterned in white. Fins and fluke: Its dorsal fin is placed slightly forward of the center of the body and is triangular in shape, and the flippers are very small and rounded at the tips. Flukes are small and pointed at the tips with a slight center notch. Size: They are quite small, averaging 6 feet in length and 270 pounds. Feeding: Dall s porpoise eats a wide variety of prey species including squid, small schooling fish such as capelin, sardines and herring. It usually consumes pounds of food each day. Mating and Breeding: Sexual maturity is reached at 6.5 feet or at 8 years of age for males and about 5.5 feet or seven years for females. Calves average about 3.5 feet at birth and weigh 55 pounds. Calves may nurse for 2 years and the calving interval is probably about 3 years. Gestation period is between 10 to 12 months. Distribution and Migration: They are found only in the north Pacific, ranging from Baja to Alaska. They are year round residents Natural History: It may be the fastest swimmer of all the small cetaceans and has reached speeds of 30 knots. They are often found in the company of Pacific white-sided dolphins. Status: They are still numerous but in urgent need of protection due to the numbers caught in fishing nets.

9 THE BLUE WHALE (Balaenoptera musculus) Description: Blue whales are long and streamlined. They are rorqual whales, a family of baleen whales with pleated throat grooves that expand when the animal takes in water while feeding. They have throat grooves that extend from the throat to the navel. Blue whale baleen is black with over 800 plates. Color: Blue whales are an overall blue-gray color, mottled with light gray. Cold-water diatoms adhere to their skin and sometimes give their bellies a yellowish tinge, giving the blue whale its nickname of "sulfur bottom." Fins and Flukes: Their pectoral (side) flippers are long and the tail flukes are broad and triangular. Size: The blue whale is the largest animal inhabiting the earth. There are records of individuals over 100 feet long, but feet is probably average. They are about as long as three school buses. An average weight for an adult is 200,000 to 300,000 pounds ( tons). Its heart alone is as large as a small car. Feeding: The favorite food of these giants is krill, or shrimp-like euphausiids, that are up to three inches long. Blue whales must eat two to four tons of krill a day during the feeding season. During the summer months, they concentrate on feeding around the Channel Islands, Monterey Bay, and the Farallon Islands. During the winter months, they migrate to the warmer waters in Mexico and Costa Rica. Mating and Breeding: Females give birth to calves every two to three years. They remain pregnant for about one year before giving birth. When born, the blue whale calf is about 23 feet long and weighs 5,000 to 6,000 pounds. A nursing blue whale mother produces over 50 gallons of milk a day. The milk contains 35 to 50% milk fat and allows the calf to gain weight at a rate of up to 10 pounds an hour or over 240 pounds a day! At six months of age and an average length of over 52 feet, the calf is weaned. The blue whale reaches sexual maturity at around 10 years of age. Distribution and Migration: Blue whales have been found in every ocean of the world. Blue whales swim individually or in small groups. Pairs are very commonly seen. Approximately 2,000 blue whales live off the California Coast and migrate to Mexico and Costa Rica. More and more are seen passing by Piedras Blancas. Natural History: They spend summers feeding in the north Pacific and take lengthy migrations towards the Equator as winter arrives. They travel about five miles an hour but accelerate to more than 20 miles an hour when agitated. They are among the loudest animals on the planet, emitting a series of pulses and groans, and it s thought that, in good conditions, they can hear each other up to 1,000 miles. Status: The blue whale was too swift and powerful for the 19th century whalers to hunt, but with the arrival of harpoon cannons, they became a much sought after species for their large amounts of blubber. The killing reached a peak in 1931 when 29,649 blue whales were taken. By 1966, blues were so scarce that the International Whaling Commission declared them protected throughout the world. Today, there are between 8,000-9,000 blue whales in the oceans, and while they are still considered an endangered species the numbers are increasing. We can see them in the summer and fall off the central California coast. The 2,800 blue whales that feed along the California coast make up the largest concentration of blue whales in the world.