The Wild Life Blog

Bear Hybernating

Winter season introduces many changes in the way animals live and survive, such as the activity of migration by whales, seals, turtles, eels, crabs, fish, butterflies, etc. Hibernation is a popular term, when referring to animals during winters. Basically, animals resort to hibernation in order to escape from the chillness of the weather. They use it as a medium for preserving the energy and heat in their body, which is assisted by their own body system.

True hibernation is an inactive sleep-like state, which some animals enter during the winter season. The body of the animal also goes through a number of changes, such as the body temperature becomes lower than normal and the heart beat and breathing slows down tremendously. Talking about bears, they do not experience true hibernation. Rather, they go through a state of ‘winter lethargy’, which in general terms is called Hibernation.

Example :-

Bears enter the winter lethargy state gradually and do not awaken until disturbed. However, if the bear is dormant, it is quite easy to awaken him. This is yet another contrast as true hibernators are hard to wake-up and enter dormancy quickly. Before entering their dens for winter lethargy, bears gain considerable amount of weight. The accumulated fat is the only source of energy that fuels their metabolic activity, providing its fluid needs. The basic purpose of hibernation is to bypass the winter season, during which the food supplies get restricted. Thus, in order to conserve energy, bears do not eat, defecate or urinate during winter lethargy. However, when the bears come out of their winter lethargy, they are much thinner than when they entered. Bears lose about 22 percent of their muscle strength during their food-less, three to four month hibernation.

Kingfisher

The 2008 figures show 3,000 sightings compared to 4,000 in 2007 – despite a 17 per cent rise in visitor numbers across the waterways network. Officials are baffled by the drop but suspect it is a statistical ‘blip’ rather than a dramatic fall in the number of animals.
Many more people now use waterway tow paths as a route to work – walking, running or cycling – as well as for spotting wildlife.

“If there is a similar fall-off in numbers next year then there will be a cause for concern but at the moment I am not too worried,” Ecology manager for British Waterways.

The results of the fifth annual wildlife survey reveal that the wet spring and summer took its toll on at least some species. The kingfisher, which last year was fourth on the most-seen list with 314 sightings, dropped to 11th this year with only 138 sightings.
Heavy rain and flooding happened at the worst time for the kingfisher as young birds were about to fledge and although there are no specific proofs its suspect that many nests in riverside banks are washed away.

Reports of heron, moorhen and cormorant were also well down on last year as were sightings of water vole and its main predator the invasive American mink.
Others – the only native creature capable of competing with the mink, is also being increasingly seen in cleaner rivers.

This year’s survey, focused on dragonflies and damselflies and more than 350 were spotted across the country, particularly in the North West.
British Waterways’ ecologists say that the presence of the colorful insects is a key indicator of good water quality and a healthy local ecosystem as they need to lay their eggs in or near water.

Other key findings:
* Frogs moved up six places in the table to become the sixth most sighted animal with more than half spotted in Scotland.
* Mallards, swans and moorhens were the most commonly sighted species.
* Invasive terrapins, mainly released pets, were widespread but in low numbers.
* Water voles were spotted in even numbers across the country.
* Mink were seen most frequently in the East Midlands, Yorkshire and Scotland, but were entirely absent in London.

White Tiger

A white tiger is a tiger with a genetic condition that nearly eliminates pigment in the normally orange fur although they still have dark stripes. This occurs when a tiger inherits two copies of the recessive gene for the paler coloration: pink nose, pink paw pads, grey-mottled skin, ice-blue eyes, and white to cream-coloured fur with black, grey, or chocolate-coloured stripes. Mr. H.E. Scott of the Indian police gave this description of a captive white tiger’s eyes-”The colourings of the eyes are very distinct. There is no well defined division between the yellow of the comex and the blue of the iris. The eyes in some lights are practically colourless merely showing the black pupil on a light yellow background.
White tigers do not constitute a separate subspecies of their own and can breed with orange ones, although all of the resulting offspring will be heterozygous for the recessive white gene, and their fur will be orange. The only exception would be if the orange parent was itself already a heterozygous tiger, which would give each cub a 50% chance of being either double-recessive white or heterozygous orange. If two heterozygous tigers, or heterozygotes, breed on average 25% of their offspring will be white, 50% will be heterozygous orange (white gene carriers) and 25% will be homozygous orange, with no white genes. In the 1970s a pair of heterozygous orange tigers named Sashi and Ravi produced 13 cubs in Alipore Zoo, of which 3 were white. If two white tigers breed 100% of their cubs will be homozygous white tigers. A tiger which is homozygous for the white gene may also be heterozygous for many different genes. Inbreeding promotes homozygosity and has been used as a strategy to produce white tigers. Inbreeding is detrimental when deleterious genes are present. Otherwise it is harmless. The white gene may be considered deleterious or categorized as a genetic defect.