Galapagos penguin (Spheniscus mendiculus)

KingdomAnimalia
PhylumChordata
ClassAves
OrderSphenisciformes
FamilySpheniscidae
GenusSpheniscus (1)
SizeLength: 53 cm (2)
Top facts

The Galapagos penguin is classified as Endangered (EN) on the IUCN Red List (1).

The Galapagos penguin (Spheniscus mendiculus) is the most northerly of all penguins, occurring on the Galapagos Islands, on the equator (3). It is the smallest of the South American penguins, with an average length of less than 50 centimetres (4). 

This diminutive penguin has a black head and upperparts, with a narrow white line extending from the throat around the head to the corner of the eye (4). The underparts are white, with two black bands extending across the breast (2). The upper part of the bill and the tip of the lower part of the bill are black, but the rest of the bill and a bare patch around the eye and bill are pinkish yellow. The female Galapagos penguin is generally smaller than the male (4). Juveniles have a completely dark head, and lack the dark breast bands seen in adults (2). 

The Galapagos penguin has a longer and more slender bill than other penguins (5).

The Galapagos penguin is endemic to the Galapagos Islands, Ecuador. Approximately 95 percent of the population occurs on the western islands of Ferdinandina and Isabela, with the remaining 5 percent on Bartolome, Santiago and Floreana (2). 

This species has the smallest breeding range and lowest population size of any penguin (4). In 2007, the population numbered just 1,000 individuals (2).

The Galapagos penguin nests in cracks, caves and depressions in the island’s lava flows. It feeds near the shore in cool, nutrient-rich oceanic waters, where there is an abundance of prey year-round (2) (6).

The Galapagos penguin displays a great number of unique behavioural adaptations that allow it to inhabit the Galapagos Islands and keep cool on land. These include standing with the flippers extended to aid heat loss, as well as panting and seeking shade. When standing on land, it tends to adopt a strange hunched posture, which shades the bare feet, a major site of heat loss (4). 

The flexibility of breeding in the Galapagos penguin allows it to take advantage of times of high food abundance. When the surface temperature of the sea becomes high, the water becomes very poor in nutrients resulting in food shortages. During these periods, known as El Nino Southern Oscillations (ENSO), the Galapagos penguin will delay breeding completely until food resources improve (4). 

Pair bonds are for life, enabling the Galapagos penguin to begin breeding quickly when conditions improve. The bond is reinforced by mutual preening and bill tapping. Two eggs are produced at an interval of around four days. Incubation takes up to 40 days and is shared by the male and female. After 30 days, the chicks develop plumage to protect them from the sun, and the chicks fledge after 65 days (4).

The main threat facing this unique penguin is the increasing frequency of ENSO events, which reduce the strength of the cool currents this species needs to survive and causes fluctuations in its prey (6). The 1982-1983 ENSO resulted in the catastrophic loss of 77 percent of the Galapagos penguin population through starvation. A slow period of recovery followed, but the 1997-1998 ENSO resulted in another precipitous population crash of 66 percent. Such events may have a disproportionate affect on females, which can skew the sex ratio and make recovery from population crashes even slower (2). Furthermore, during periods of food shortages, the Galapagos penguin forages individually and makes no attempt to breed until sea temperatures decrease once again (4). 

Other threats facing this beleaguered penguin include global climate change, which may increase the frequency of ENSO events, accidental drowning in fisheries, oil spills, predation by introduced feral cats, and avian malaria, which is carried by mosquitoes brought to the Galapagos islands by humans in the 1980s (2).

All populations of the Galapagos penguin occur within the Galapagos National Park and Marine Reserve. At present, all populations are closely monitored and feral animals are controlled (2). 

Proposed measures to help this highly endangered species include discouraging the use of fishing nets in foraging areas, preventing coastal developments in breeding areas, and providing nest-boxes in predator free areas to allow research into the reproductive success of this species (2). 

As the population of the diminutive and uniquely adapted Galapagos penguin is so small and precarious, and restricted to just one breeding location, unfortunately this species is extremely vulnerable to extinction (2).

For more information on the Galapagos penguin see:

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

  1. IUCN Red List (July, 2011)
    http://www.iucnredlist.org/
  2. BirdLife International (July, 2011)
    http://www.birdlife.org/datazone/speciesfactsheet.php?id=3864
  3. MarineBio - Galapagos penguin (July, 2011)
    http://marinebio.org/species.asp?id=246
  4. International Penguin Conservation Work Group - Galapagos penguin (July, 2011)
    http://www.penguins.cl/galapagos-penguins.htm
  5. BBC Wildfacts - Galapagos penguin (July, 2011)
    http://www.bbc.co.uk/nature/wildfacts/factfiles/364.shtml
  6. Schulenberg, T.S. (2010) Galapagos penguin (Spheniscus mendiculus). In: Schulenberg, T.S. (Ed.) Neotropical Birds Online. Cornell Lab of Ornithology, Ithaca. Available at:
    http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=93511