April172007

Nature Photos of the Week

April 19, 2007

Baja's Whales, Sea Lion, and Osprey!

The Gray Whale or Grey Whale (Eschrichtius robustus), more recently called the

Eastern Pacific Gray Whale, is a whale that travels between feeding and breeding

grounds yearly. It reaches a length of about 16 meters (52ft), a weight of 36 tons and

an age of 50–60 years. Gray Whales were once called devil fish because of their

fighting behavior when hunted.

The Gray Whale is the sole species in the genus Eschrichtius, which in turn is the sole

genus in the family Eschrichtiidae. This animal is one of the oldest species of mammals,

having been on Earth for about 30 million years. In the remote past it was preyed

upon by Megalodon sharks (which are now extinct).

The California Sea Lion (Zalophus californianus) is a coastal sea lion of the

northern Pacific Ocean. Males grow to 300 kg (600 lb) and 2.4 m (8 ft) long, while females

are significantly smaller, to 100 kg (200 lb) and 2 m (6.5 ft) long. The California Sea Lion

has a streamlined body that contains a layer of blubber under the skin to provide warmth and buoyancy. Their large eyes help them adjust to low levels of light in underwater environments,

while their whiskers augment their sense of touch.

Osprey, Pandion haliaetus is a medium-large raptor which is a specialist fish-eater

with a worldwide distribution. It occurs in all continents except Antarctica, but in

South America only as a non-breeding migrant. It is often known by other colloquial

names such as fishhawk, seahawk or Fish Eagle. The Osprey is a species with many

unique characteristics, and therefore has been given its own taxonomic genus, Pandion,

and family, Pandionidae.

Osprey breed by freshwater lakes and sometimes on coastal brackish waters. Rocky

outcrops are used on Rottnest Island off the coast of Western Australia. Some nests have

been used for over 70 years. The nest is a large heap of sticks built in trees, rocky outcrops,

telephone poles or artificial platforms. In some regions with high Osprey densities, such as

at the mouth of the Connecticut River, most ospreys do not start breeding until they are

five to seven years old, and there may be a shortage of suitable tall structures. If there

are no nesting sites available, young Osprey may be forced to delay breeding. To ease

this problem, platforms may be erected to provide more sites suitable for nest building.