Pelecanoides magellani

Geographic Range

Magellanic diving petrels are found in the coastal and nearshore areas of southern Chile, Tierra del Fuego, and southern Argentina. They are found in fjords and coastal waters up to 125 km from shore.

• Biogeographic Regions
• neotropical neotropical
  • native native
• atlantic ocean atlantic ocean
  • native native
• pacific ocean pacific ocean
  • native native

Habitat

Magellanic diving petrels are mainly found foraging in nearshore, coastal waters. They breed on small, nearshore islands in coastal channels and fjords. Breeding islands generally have soft soil and some vegetation. Magellanic diving petrels dig nesting burrows in this soil and overhanging vegetation may help to mask the burrow entrance.

• Habitat Regions
• temperate temperate

• Aquatic Biomes
• coastal coastal

Physical Description

Magellanic diving petrels are about 19 cm long and recorded weights are from 145 to 174 g (although this is based on a small sample size). They are similar in appearance to other diving petrels , with black plumage dorsally and white plumage on the ventral surfaces. They have grey mottling on their flank and sides of their breasts. Soon after a molt, feathers on their back, rumps, and wings have white tips to them. They have a white line that runs from just above each eye, laterally down the neck to join with the white of the breast and flanks. Their bill is black and the feet and legs are blue, with black webbing. They are distinguished from other diving petrels by the white markings that run from their eyes along the neck and by dimensions of the bill. Wings are from 120 to 133 mm long, bill lengths are from 15 to 17 mm, and tails are from 34 to 44 mm. There are no described subspecies and sexual dimorphism is not reported. Like other diving petrels , they are able to store and transport prey items in a gular pouch, formed by a distensible portion of skin in the throat. This characteristic is hinted at by their generic name Pelecanoides , referring to its similarity to the gular sac of pelicans ( Pelecanidae ).

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

There is no information on mating in Magellanic diving petrels. Like their relatives, they are thought to be monogamous, with pairs occupying nesting burrows in small territories at breeding colonies.

• Mating System
• monogamous monogamous

There is very little information on breeding in Magellanic diving petrels. They seem to nest in burrows among vegetation on coastal, channel islands throughout their range. Eggs are laid from November to December and fledglings have been observed in March. Adults have a post-nuptial molt from April to June. Females lay a single egg. Other aspects of their reproduction are probably similar to common diving petrels .

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

Males and females both incubate, brood, feed, and protect their single young until they become independent.

• Parental Investment
• altricial altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female

Lifespan/Longevity

Magellanic diving petrel longevity has not been documented, although it is presumed to be similar to that of common diving petrels .

Behavior

Like other diving petrels , these birds fly with characteristic fast wing beats close to the water. They seem to molt all of their flight feathers at once, leaving them flightless for several weeks. However, the loss of their primary feathers doesn't impact their ability to dive and capture prey. Magellanic diving petrels are social at breeding colonies, which may be dense, but are generally seen alone or in small groups outside of the breeding season. They spend most of their time on the water when not at breeding colonies. They visit breeding colonies at night, resting in their nesting burrows, and seem to forage mainly during the day, although they will forage at night as well. Magellanic diving petrels are thought to be sedentary. They have been found up to 128 km from land, but are thought to generally occur in coastal waters near their breeding colonies.

• Key Behaviors
• flies
• diurnal diurnal
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• social social

Home Range

Home range sizes are not reported.

Communication and Perception

There is no information on communication in Magellanic diving petrels. They are likely to be similar to their close relatives, common diving petrels ( Pelecanoides urinatrix ), which are silent, generally, at sea but very vocal at breeding colonies at night.

• Communication Channels
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Magellanic diving petrels capture aquatic invertebrates, especially crustaceans, and small fish by diving, either from flight or from a surface dive. Like their diving petrel cousins , they are likely to be strong in underwater pursuit, propelling themselves underwater with their wings and steering with their tails. They seem to feed mainly in coastal, nearshore waters.

• Primary Diet
• carnivore carnivore
  • piscivore piscivore
  • eats non-insect arthropods

• Animal Foods
• fish
• aquatic crustaceans

Predation

Like other diving petrels , they seem to dive in response to threats rather than fly. They seem to escape much predation by gulls and skuas by visiting their nesting colonies mainly at night, landing briefly outside of their burrows and making a quick retreat to the safety of the burrow upon arrival. If they are forced to walk any distance on land to their burrow, there is a high probability that they will fall prey to larger birds.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Magellanic diving petrels are important predators of marine invertebrates and small fish in the coastal channels and fjords they inhabit.

Economic Importance for Humans: Positive

Magellanic diving petrels are important members of nearshore marine environments throughout their range and may attract ecotourism interest.

Economic Importance for Humans: Negative

There are no adverse effects of Magellanic diving petrels on humans.

Conservation Status

Magellanic diving petrels have a large distribution and are considered common throughout their range. They are listed as "least concern" by the IUCN.

Other Comments

Pelecanoides magellani were once considered conspecific with Pelecanoides urinatrix .

Diving petrels are strikingly similar physically and ecologically to the northern hemisphere puffins, murres, and auklets ( Alcidae ), especially little auks ( Alle alle ).

Additional Links

Encyclopedia of Life

Contributors

Tanya Dewey (author), Animal Diversity Web.

References

Brooke, M. 2004. Albatrosses and petrels across the world . Oxford: Oxford University Press.

del Hoyo, J., A. Elliott, J. Sargatal. 1992. Handbook of the Birds of the World, Volume I . Barcelona: Lynx Edicions.