Monday 30 July 2012 Long-tailed field mouse - Comic of the Forest

The long-tailed field mouse (Apodemus sylvaticus) is commonly found in the woods, hedgerows and scrub throughout the countryside in Britain and Ireland. It also ranges to Scandinavia to the north, to Ukraine to the east and to the south in north western Africa and on many Mediterranean islands.

It is the cousin to the yellow-necked mouse, but the long-tailed field mouse is smaller and darker. Cats, weasels, stoats, foxes, owls and moles will make a meal of the mouse if they can, but the long-tailed field mouse is a great jumper and climber and not easy to catch. If it is caught by the tip of its tail, it will immediately shed the end of its tail and make its escape. The shed tip may never grow back. On the IUCN Red List of threatened Species it is classified LC (least concern).

Also called the wood mouse, it is mainly nocturnal and will eat a varied omnivorous diet including seeds and nuts when they are plentiful and small insects, snails, spiders and larvae mainly in the spring along with roots, berries and other fruit. It lives underground in burrow systems and has chambers for nesting and storing food. Its nests consist of balls of dry grass, leaves and moss. Sometimes it uses vacated bird’s nests to store food. It lives mainly outdoors in grassland and cultivated fields, but it will live inside a building during an especially harsh winter.

It has a breeding season from February to October which consists of a free-for-all competition between males and females. This results in multiple paternity litters. After 25 or 26 days the litters are born and usually contain five young. They are independent at three weeks and sexually active at two months.

The long-tailed field mouse is larger than a common house mouse measuring 8.1 cm (3.9 inches) to 10.3 cm (4 inches) nose to tail. The tail is 7.1 cm (2.8 inches) to 9. 3 cm (3.6 inches) long. They weigh between 13 grams (.46 ounces) and 27 grams (.95 ounces).

The long tailed field mouse does not hibernate, but it does greatly reduce its physiological activity during sever winter seasons. At night when they are most active they sometimes mark their food hiding places with conspicuous objects such as a bright leaf or large twig. They use these signs as landmarks while they are foraging for food. Basically, they are organized food gatherers, but have scramble competition for copulation.

Picture of the long-tailed field mouse by Rasbak, licensed under GNU Free Documentation License. You can help spreading the word about this animal by liking it on facebook

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Thursday 26 July 2012 The Golden-Bellied Water Rat -Australia's Resilient Rodent

The Golden-bellied water rat (Hydromys chrysogaster) is another one of the many hidden gems within Australia's wildlife; commonly mistaken for the famed platypus due the fact that they inhabit many of the same waterways and bear a resemblance from a distance, golden-bellied water rats are just as unique and intriguing. Native to Australia, New Guinea, and their surrounding islands, the golden-bellied water rat is a crucial part of the ecosystem with roles as both predator and prey.

The golden-bellied water rat is typically found along the shorelines of ponds, rivers, and lakes in burrows where a mother and pups will live or a single water rat will live alone. The mother weans her young quickly and within about 35 days the pups are fully independent. Golden-bellied water rat burrows are often found along coastlines as well, but they usually stay withing range of a fresh water source; the water rat's burrows commonly have multiple chambers and entrances, and seeking cover in the burrow is its only real defense mechanism against predators like birds of prey and snakes.

The golden-bellied water rat is brown to gray in color with a lighter brown or tan underbelly and a very distinctive broad-based tail that is tipped white. They typically grow to be around 24 inches (60cm) long and can weigh 30 ounces (850g) or more. Water rats live on the land but get all of their food from the water; prey items include aquatic insects, crustaceans, mollusks, frogs, toads, and fish. The golden-bellied water rat has also been known to feed on one of the most toxic amphibians in the world, the ominous cane toad.

The golden-bellied water rat is perfectly suited to its environment with webbed toes on both feet, a long and slender snout, and a strong tail for agility in the water; these animals are said to resemble an otter when swimming and hunting more than a rat. The golden-bellied water rat also has the curious ability to tolerate polluted, clouded, and brackish waterways, giving them an advantage in habitat competition. The water rat is warm-blooded and therefore must contend with potentially dangerous cold spells, and they are also susceptible to hypothermia; another of their adaptations in the form of a layer of special insulating fat helps them combat the winter temperatures when they must still hunt in the frigid water.

The golden-bellied water rat is abundant and thriving and is considered a low risk as far as endangered species watch lists are concerned. Outside of being a great example of animal diversity and a key element in the food chain and ecosystem as a whole, the golden-bellied water rat may also hold potential breakthroughs in medical research due to its tolerance of toxins ingested internally, as with the cane toad, and toxins in the environment like polluted waters.

Picture of the Golden-bellied water rat by Mikeybear, licensed under the Creative Commons Attribution 3.0 Unported license. You can help spreading the word about this animal by liking it on facebook

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Tuesday 24 July 2012 Pacific Sleeper Shark - the Silent Killer

The Pacific sleeper shark (Somniosus pacificus), a quiet but deadly predator, lives in deep water, 2000m (6600 ft.), and on the continental shelves in temperate water. It lives in the North Pacific from Japan along the Siberian coast and the Bering Sea. Also, off the coast of southern California, Baja California and Mexico. In the Atlantic they are found off the coast of Uruguay. In Australasia they live from south Tasmania to eastern New Zealand. Usually just lying on the bottom of the sea, they were named sleeper sharks, but they can be very aggressive and never stop moving. This is proven by the content of the stomach of some captured specimens. They eat salmon and sea lions which are fast moving animals.

Pacific sleeper sharks are bottom feeders and prey mainly on fish, Giant Octopus and squid as well as flounders, rockfishes, pollocks, shrimps, hermit crabs and soles. Their diet depends on how big they are. Normally, the males grow to 4.4 meters (14 ft.) and females a bit less but have been seen at 7 meters (23 ft) and weigh from 700 to 800 pounds.

Pacific sleeper sharks swallow their prey whole and usually alive, if they can, and break any pieces too large to swallow with their unusual teeth. The upper teeth are like spikes and the lower teeth are oblique cusps. A 12 ft. female was found with an intact Southern Rightwhale dolphin in her stomach. When food is hard to find they are also scavengers and feed on carrion.

For reproduction, the eggs are retained within the body (ovoviviparous) in a brood chamber in the female until the embryos develop. The embryos are nourished from a yolk sac inside the egg and when they break out of the egg, still inside the mother, they are born soon afterwards. Called pups, there is sometimd>