Skip to main content

Gray Whale

Eschrichtius robustus
As it is Mother's Day, we're going to learn about one really awesome mother from the Animal Kingdom-- the Gray Whale!

Gray Whale breeding season takes place in November and December, and happens while the Whales are wintering in warmer waters near the Equator. Females gestate for a whopping 13.5 months and give birth to a single calf while in their wintering grounds the following year. Calves are born in safer waters off of Baja, Mexico that are free from predators, and the mothers will help lift their infants up to the surface so that they can breathe... at least until they become stronger swimmers. Calves are around 4ft long at birth, and grow very quickly. They can drink up to 80 gallons of milk a day, and that milk is 53% fat!

Eventually, the mother an calf must travel back to colder climates in order to feed. The wintering waters are safe for giving birth, but that is because there is so little food, and thus very few predators. All Gray Whales migrate, and they actually take part in one of the greatest animal migrations in the world, travelling as far as 12,500 miles (20,000km) round trip each year. Females and calves are the first to leave the warm winter waters, destined for the nutrient rich seas of the north. But the trip is not easy! Not only is the swim difficult for the calves due to it's distance, it is also incredibly dangerous thanks to all the predators (like Killer Whales) that are out to get them.

Calves remain with their mothers for around a year, and will themselves take about 8 years to reach sexual maturity. One fact that I found particularly interesting is that the female Gray Whales are often larger than the males, which is unusual for Cetaceans. Sperm Whales, for example, have some of the most ridiculous sexual dimorphism of any mammal.

Gray Whales also have a very distinctive look to them, thanks to the various parasites and growths that collect on their skin. Calves are born completely smooth, and will collect their barnacles and lice as they age. Doesn't sound especially pleasant, does it?

Currently, Gray Whales can only be found in the Pacific Ocean. Before the growth of Commercial Whaling they also lived in the Atlantic, but they are now extinct in that particular area. Gray Whales almost disappeared from the planet completely, but they are now protected and their population is slowly rebounding. Boat collisions, fishing gear entanglement, habitat degradation, and the effects of climate change all continue to impact the species.
IUCN Status : Least Concern
Location : Pacific Ocean
Size : Length up to 50ft (15m)
Classification : Phylum : Chordata -- Class : Mammalia -- Order : Cetacea
Family : Eschrichtiidae -- Genus : Eschrichtius -- Species : E. robustus
Labels:

Comments

Post a Comment

Popular posts from this blog

Bornean Orangutan

The Bornean Orangutan is one of two extant Orangutan species in the world. It is the third largest primate (after Gorillas) and is the largest primarily tree-dwelling animal in the world. Males are substantially larger than females, and average at around 165lbs. Bornean Orangutans are largely solitary. A handful might live within a small range but they will seldom interact with one another. Males and females only meet up to breed, which happens only once every several years. A young Orangutan will stay with it's mother for about five years, and the females tend to go about eight years between births. That is the longest interim period of any animal! Sadly, the Bornean Orangutans are in a lot of trouble. They need large forests in order to thrive, and deforestation and habitat degradation has left many homeless. They are also hunted for meat and for traditional medicines. Conservation areas are being established to help these guys in the wild, and it is believed that there are a
59 comments
Read more

Four!

For anyone who was counting, yesterday was our birthday-- four years! Four years filled with animals from A to Z, more than 1,100 of them! I can't thank my readers enough, it's been wonderful! And in celebration of that milestone... I'm taking a break. Hopefully not forever, but for a little bit at least. In the mean time I plan on getting a new layout out, along with some updates to some of the older articles. I'll post updates here and on the Facebook page, I'm also brainstorming some new animal-related projects, so keep an eye out! Thanks again for four awesome years!
18 comments
Read more

Halloween Crab

Gecarcinus quadratus The Halloween Crab goes by many names, including the Red Land Crab, Whitespot Crab, and Moon Crab. I personally like Halloween Crab though, since it really reflects the interesting colors. They have black carapaces, orange-red legs, and purple claws! Halloween Crabs live in the Pacific coast mangroves and forests of Central and South America. They actually live in the forests as adults, and return to the ocean in order to reproduce. Did you know that they live as far away as 18 miles (30km)  from water? Not where you normally think Crabs to be! While living in the forest, the Crabs forage nocturnally for different plant matter, including leaves and sapling. They also dig long burrows into the ground for protection. These burrows can measure nearly 5 ft long! Halloween Crabs are sometimes kept in captivity, and can be very tricky pets due to their excellent climbing skills. IUCN Status :  Not Listed Location :   Cent
Post a Comment
Read more