Rohmatul Ula, Sultan Iskandar Ini materi Bahasa Inggris, kita tentang Orcinus Orca (Killer Whale) ada 4 artikel, ini artikel pertama GENERAL DESCRIPTION The orca or killer whale is a toothed whale that is an efficient predator, even attacking huge young blue whales. Their only enemy is human beings. Orcas live in small, close-knit, life-long pods and have 1 blowhole. The killer whale belongs to the family of dolphins and is the biggest dolphin. It is sometimes called the wolf of the sea because its behavior is similar to that of wolves. SIZE Orcas grow to be about 27-33 feet (8-10 m) long, weighing more than 8,000-12,000 pounds (3.600-5.400 kg). The male orca is larger than the female. They are the largest member of the dolphin family. SKIN, SHAPE AND FINS The Orcas skin is mostly black with distinctive white patches. Orcas have stocky bodies and a rounded head with a distinctive beak. They have a tall, falcate (sickle-shaped) dorsal fin and large, paddle-like flippers. The dorsal fin of the male is taller (up to 6 ft tall) and more upright than that of the female (whose dorsal fin is up to 4 ft tall). DIET AND TEETH Orcas are efficient hunters that eat a very diverse diet of fish , squid , sharks , marine mammals (including whales and seals), turtles, octopi, and birds (penguins and gulls). They have even been known to attack young blue whales and other large whales. They have 10-13 pairs of large, interlocking conical, enameled teeth distributed in BOTH the upper and lower jaws (for a total of 20 to 26 pairs, so the orca has from 40 to 52 teeth). The teeth curve inwards and backwards - this helps the orca catch its prey. Teeth average about 3 inches (7.6 cm) long and about 1 inch in diameter, but some are even longer. Members of a pod frequently cooperate in hunts. An average-sized orca will eat 551 pounds (250 kg) of food a day. The Food Chain of an Orca Orca Seal Squid Fish Zooplankton Phytoplankton SOCIAL GROUPS Orcas live in small pods of 6-40 whales; they are very social animals. The bonds between the close-knit members of Orca pods are strong and last for life. The members of a pod hunt together in a very sophisticated manner, attacking even very large prey and then sharing it. The pod members protect the young, the sick and the injured. DIVING, BREACHING, SPYHOPPING, AND TAIL SLAPS Orcas can dive to a depth of 100 feet (30 m) in order to hunt. Orcas commonly breach (swim at very fast speeds toward the surface in order to rise above the surface of the water and then fall back onto the surface, splashing and making noise). Spyhopping (poking the head out of the water to look around) and tail slapping are also common orca activities. The purpose of these activities is unknown. SPOUTING - BREATHING Orcas breathe air at the surface of the water through a blowhole located near the top of the head. Their blow is a single, low bushy cloud. SPEED Orcas are very fast swimmers. They can swim up to 30 mph (48 km) in bursts in order to catch prey. VOCALIZATION Orca vocalizations include clicks used in echolocation, whistles, and scream-like pulses. The sounds are used to communicate with other orcas, for mating purposes, and for locating prey. Different pods (long-lasting groups of orcas) have distinctive accents and can recognize members by this accent. HABITAT AND RANGE Orcas whales live in waters ranging from tropical to arctic, and both coastal and deep oceanic waters. They are found in all the worlds oceans and most of the seas. Orcas sometimes enter estuaries, but dont go far from the sea. MIGRATION Orcas dont make long, seasonal migrations. They may, however, cover an area of hundreds of miles (or kilometers) in order to find seasonal prey. REPRODUCTION Orca breeding occurs mostly in the winter to early spring while near the surface and in warm waters. The gestation period is about 16-17 months and the calf is born tail first (this is normal for cetaceans) and near the surface, usually between October and March. The newborn instinctively swims to the surface within 10 seconds for its first breath; it is helped by its mother, using her flippers. Within 30 minutes of its birth the baby whale can swim. The newborn calf is about 6.5-8 feet (2-2.5 m) long, weighing up to 400 pounds (180 kg). Twins are extremely rare; there is almost always one calf. The baby is nurtured with its mothers milk. The mother and calf may stay together for a year or longer. Female orcas reach maturity at 6-10 years old, and males at 12-16 years old. LIFE SPAN Male orcas have a life expectancy of 50-60 years. Females have a life expectancy of 90 years. POPULATION COUNT The species is in no danger as their numbers are abundant. CLASSIFICATION Orcas (Orcinus orca) are toothed whales (Suborder Odontoceti) They are one of 76 cetacean species, and are marine mammals. This species was named by Linnaeus in 1758. Kingdom Animalia (animals) Phylum Chordata (vertebrates) Class Mammalia (mammals) Order Cetacea (whales and dolphins) Suborder Odontoceti (toothed whales) Family Delphinidae (oceanic dolphins) Genus Orcinus Species orca ORCA ACTIVITIES A simple coloring print-out about Killer whales. A coloring print-out about Killer whales with information. An Orca quiz to print out. A first grade addition activity. Solve the 1-digit addition problems, then do letter substitutions to find the name of a whale. A first grade subtraction activity. Solve the 1-digit subtraction problems, then do letter substitutions to answer a whale question. A Killer whale word hunt activity - For second and third graders. Dolphin Theme Page enchantedlearning/subjects/whales/species/Orca.shtml
Posted on: Mon, 11 Nov 2013 11:34:11 +0000