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Daily News Analysis

Sea Lions

30th June, 2023 Environment

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  • The Channel Islands Marine & Wildlife Institute reported 1,000 sightings of sick and dead marine mammals from June 8 through 14.
  • They were found dead and sick along the coast of Southern California.
  • Many sick sea lion and new born pups are rescued from the beach and taken care at marine mammal care centres.

Other Details

  • Outbreak of algae bloom, also known as red tide, is being blamed for causing sickness and death to sea lions and dolphins.
  • As per California wildlife experts there is a sudden surge in animals falling ill to a neurotoxin.
  • Small fish consume the toxin and pass it up the food chain.

Symptoms of Sickness

  • Swaying their heads back and forth.
  • Foam at the mouth.
  • Experiencing seizures.
  • Lying listlessly in the surf.

California Sea Lions

  • The scientific name of California sealions is Zalophus californianus.
  • These animals belong to the family Otariidae.
  • This coastal eared seal is one of six species of sea lions and is native to western North America.


  • Large and playful eyes.
  • Pale to dark brown in appearance but seems black when wet.
  • A thick neck.
  • They can reach a maximum length of about 2.5 metres.
  • Weight could be as heavy as 1200 pounds.
  • In captivity it can live more than 30 years.


  • Important for Marine diversity.
  • Tourist attractions and hence can contribute to support economy.
  • Sea lions are considered a sentinel species, it means they are the animals that can help identify environmental risks to humans.

Diet and Habitat

  • They feed on a wide variety of seafood, mainly squid and fish, and sometimes clams.
  • They could be found along the western coast and islands of North America, from southeast Alaska to central Mexico.
  • It is mostly a coastal animal that frequently comes out from the water when swimming.
  • Highly trainable and are generally friendly to humans.


  • Algae Bloom
  • Introduced species, such as dogs, carry diseases that can spread to sea lions.
  • Climate change effect on ocean currents makes their survival difficult by severely affecting the food (fish) availability.
  • Their by-catch in fisheries could be another threat for their survival.

Algae Bloom

  • The algae is a natural phenomenon that causes the production of a neurotoxin called domoic acid.
  • However a harmful algal bloom (HAB) occurs when toxin-producing algae grow excessively in a body of water.
  • Reasons of Algal bloom
    • Human induced climate change
    • Release of excess of nitrates washed out to sea.
    • Discharge of other polluting substance and industrial affluent to oceans.

Conservation Status

  • California sea lion are considered as Least Concern as per IUCN Red list.
  • It is protected by the federal Marine Mammal Protection Act (MMPA), 1972.


Consider the following statements about Californian Sea Lion:

1. It is considered as one of the most vulnerable types of sea lions.

2. This Species is friendly to humans and highly trainable.

Which of the statements given above is/are correct?

A. 1 only

B. 2 only

C. Both 1 and 2

D. Neither 1 nor 2

Answer: (B)