Monday, August 24, 2020

Wildlife of the Week!


© Five Star Whale Watching/ Andrew Lees. A male Elephant Seal lounges on the warm rocks of Race Rocks Ecological Reserve.

The ocean is composed of many moving parts; marine mammals cooperatively hunting prey, seabirds gathering and flocking around a bait ball, small invertebrates living in dense forests of green kelp, migrating whales and more! But did you know that some marine mammals, other than whales, may also migrate? Let’s take a look at one such species for this week’s Wildlife of the Week. 

The Elephant Seal is the largest of the true seals, meaning it is not a Sea Lion or a fur seal. To help imagine what features of a true seal set it apart from other pinnipeds, think of the more common Harbour Seal (small fore-flippers, no ear flaps, type of swimming). The Northern Elephant Seal that we occasionally spot in the Salish is slightly smaller than its relative, the Southern Elephant Seal. To read more about the Northern Elephant Seal, read on!

The Northern Elephant Seal may measure an impressive 4,400 pounds (males) or 1,300 pounds (females). Length for this animal ranges between 10-13 feet long. The animal is dark brown, tan or grey. Perhaps the most noticeable characteristic of the species is the large “proboscis” that only male Elephant Seals have; a large inflatable nose that hangs over their lower lip and appears a shorter version of an elephant’s trunk. 

Females do not carry this adaptation, which is primarily used for breeding purposes. Males will emit vocalizations through their nose, creating threatening noises to ward off other competitor males. Adult males also have a thick, wide neck as opposed to the females. 

Northern Elephant Seals, as their name suggests, are majorly found in higher latitudes of the globe, but as they are migratory they are also spotted in mid-latitude/southern areas for breeding. They can be spotted as far north as Alaska and as far south as California and Mexico. Feeding is generally between moulting and breeding seasons, which are respectively spring/summer and winter. Males and females even show distinct differences in geographic feeding habits, with females showing preference to more southern grounds. 

Though the Elephant Seal may appear inefficient on land, the contrary is true under the water. An excellent agile swimmer the Northern Elephant Seal spends about ¾ of its life in the sea. Capable of reaching diving depths of 1,000-25,00 feet, they search for prey such as squid, fishes, sharks and rays. 

The Elephant Seal forms complex breeding societies in which males defend a “harem”, or a group of females in which he will mate with. Males can often be aggressive, violent and very territorial to each other while in competition. Females need only wean their pup for about a month before they will return to their home in the water usually impregnated with another calf. They return the following year after about 11 months to again give birth on land in the wintertime. 

The Elephant Seal is known to form massive colonies during breeding seasons, especially in California. The animal has rebounded well from near-extinction due to commercial sealing; it continues to be a fascinating example of an extensive yearly migration (some travel 13,000 miles round trip). 

To test your knowledge on the Northern Elephant Seal, try out some trivia below! 

  1. True or False? The Northern Elephant Seal undergoes a “catastrophic moult” for 4-5 weeks in which their outer layers of fur and skin are shed. (ANS: TRUE). 
  2. The Southern Elephant Seal has a larger proboscis than the Northern Elephant Seal. (ANS: TRUE). 
  3. Female Elephant Seals have multiple pups born at one time. (ANS: FALSE). 

BONUS CHALLENGE:

What is the scientific Latin name for the Northern Elephant Seal?

Mirounga angustirostris. Can you think of any tricks to help remember this complicated name? 

Author: Alexa D./ Five Star Whale Watching.

View our Reference to read up on more about the Northern Elephant Seal! 

“Northern Elephant Seal.” NOAA Fisheries. U.S. Department of Commerce. https://www.fisheries.noaa.gov/species/northern-elephant-seal#:~:text=NOAA%20Fisheries%20is%20committed%20to%20protecting%20northern%20elephant,of%20entanglement%20in%20fishing%20gear%20or%20other%20stressors.


 

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