The hit of El Niño on Galapagos penguin

When we think of causes concerning the decline of certain animal species, one of the biggest factors that affect them are human activities. However, that is not always the case. Some populations can fluctuate in size because of natural environmental events [2].

Galapagos penguin drying wings, photo from www.arkive,org

A Galapagos penguin (Spheniscus mendiculus) can be found at the northern part of the equator of the Galapagos Island. They are known as one of the smallest penguin species that has an average height of around 50 centimeters. [1] However because of certain events such as the El Niño Southern Oscillation (ENSO), in 1980 this resulted to a decline of its population by 77%. Although 50% of its population were able to recover by 1995, the 1997 to 1998 El Niño caused its population to further reduce to 65%.  [3] The ENSO also introduces a strong negative effect on the behaviour, breeding, and reproduction of the penguins. It was concluded that breeding periods that occur during El Niño result to the failure of the survival of their nests. Galapagos penguins depend on the upwelling of the cool nutrient rich oceanic water that supports the small schooling fish that they feed on. [4] The oceanic conditions have resulted to a decline of food availability due to the increase in its temperature over the past years which have overall reduced the population to more than 50% comparing to its population during the 1970’s.

At present, its population is now around 1800 individuals. [5] Galapagos penguins are classified as Endangered (EN) according to the IUCN red list.

To know more about them, visit SeaLifeBase.

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[1] Akst, E.P., Boersma, P.D., & Fleischer, R.C. (2002) A comparison of genetic diversity between the Galapagos Penguin and the Megallanic Penguin. Conservation Genetics 3:375-383

[2] Ludwig, D. (1996) The Distribution of Population Survival Times. The American Naturalist (147)4:506-526

[3] Boersma, P. (1998) Population trends of the Galapagos Penguin: Impacts of El Niño and La Niña. The Condor (100)2:245-253

[4] Lacy, R.C., Meile, R.J., Parker, P.G., Vargas, F.H. (2013) Modeling Plasmodium Parasite arrival in the Galapagos Penguin (Spheniscus mendiculus) The Auk 130(3):440-448

[5] BirdLife International 2012. Spheniscus mendiculus. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 15 April 2015.

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