DIVING-PETRELS: PelecanoididaeCOMMON DIVING-PETREL (Pelecanoides urinatrix): SPECIES ACCOUNT
Diving-petrels are small, tubenosed seabirds that dive and swim to catch their food. They weight 4 to 8 ounces (120 to 220 grams) and are 7 to 10 inches (18 to 25 centimeters) long. Unlike other tubenoses, the tube-like nostrils of the diving-petrel project upward rather than forward. Scientists believe this is an adaptation, change over time, to diving. The bill is short and wide, with a slight hook at the tip. The short wings are used as flippers to help move the bird forward. Feathers are bluish-gray or black with white on the underside. When the birds molt, shed their feathers, they are unable to fly until new feathers grow in.
Diving-petrels live in the waters of the Southern Hemisphere. Although they prefer shallow coastal waters, they have been sighted offshore as well.
Peruvian and Magellan diving-petrels live in South American waters, while the common and South Georgian species are circumpolar, living at both the North and South Poles.
Diving-petrels prefer the colder temperatures of the ocean waters. They breed on oceanic islands and do not stray far from breeding sites.
Diving-petrels get their name from their habit of diving for their food, mainly small fish and crustaceans such as crabs and shrimp. They use their wings to propel themselves under water toward their food. Once their prey is caught, the diving-petrels use their wings to push themselves toward the waters' surface and directly back into the air.
BEHAVIOR AND REPRODUCTION
Diving-petrels are the only tubenoses that dive into the water to catch food. They typically fly low and fast over the water, and in stormy weather, often fly right into the crests of waves rather than fly over them. These birds are social, eating and breeding in herds and colonies. They come to land only to breed.
Diving-petrels nest in burrows, holes, or in the crevices of rocks. The female lays one egg that incubates, warms, for eight weeks. Both parents take turns sitting on the egg, usually for day-long periods. Eggs are laid between July and December, and newborn chicks are watched closely for the first two weeks of life. The chick will make its first flight around eight weeks, and at that time, begins to take care of itself.
Diving-petrels molt after the breeding season is over, and until their flight feathers grow back, they are flightless.
DIVING-PETRELS AND PEOPLE
Diving-petrels and people do not interact. The birds do attract birdwatchers, so they benefit marine ecotourism, travel in order to study wildlife and the environment.
ECOTOURISM: PUTTING YOUR MONEY WHERE YOUR MOUTH IS
According to The International Ecotourism Society (TIES), ecotourism is "responsible travel to natural areas that conserves the environment and improves the well-being of local people." Ecotourism benefits animal life in many ways. First, some money goes toward the cost of maintaining wildlife populations and habitats. Second, ecotourists are more likely to invest time or money into the part of the environment that they are concerned about.
Birds like diving-petrels do not interact directly with humans. But by attracting people who travel to watch birds, petrels indirectly benefit the regions where they live by bringing in revenue, money, to help sustain an environmental balance.
Except for the Peruvian diving-petrel, these birds are not threatened. The Peruvian diving-petrel is Endangered, facing a very high risk of extinction in the wild, due to excessive hunting and habitat destruction.
Physical characteristics: Common diving-petrels are 8 to 10 inches (20 to 25 centimeters) long with a wingspan of 13 to 15 inches (33 to 38 centimeters). They have the same bluish gray or darker and white coloration as other diving-petrels, and their legs and feet are bright blue. Their feet get even brighter during mating season. Their nostrils project upward.
Geographic range: Common diving-petrels are found in the Southern Ocean between 35 and 55° South latitude. They breed on islands off Australia, New Zealand, Chile, Argentina, and in the south Atlantic and Indian Oceans.
Habitat: Common diving-petrels feed in colder ocean waters close to breeding sites. They breed on oceanic islands.
Diet: Common diving-petrels dive into water to catch small fish and crustaceans such as crabs and shrimp.
Behavior and reproduction: These social birds fly low and fast through both air and water. The female lays a single egg in her burrow or crevice, and the egg is incubated for eight weeks by both parents.
Scientists estimate the lifespan of the common diving-petrel to be three to four years. Kelp gull, giant petrels, and skuas, aggressive birds that feed on smaller species, feed on these smaller birds, remove large numbers from the population each year.
Common diving-petrels and people: Bird watching of the common driving petrel benefits the ecotourism trade.
Conservation status: Common diving-petrels are not threatened. ∎
FOR MORE INFORMATION
Parkinson, Brian, and Tim Lovegrove. Field Guide to New Zealand Seabirds. London: New Holland Publishers, 2001.
Warham, John. The Behaviour, Population Biology and Physiology of the Petrels. London and San Diego: Academic Press, 1996.
"Birding." Birdwatching.com. http://www.birdwatching.com/birdingfaq.html (accessed on May 26, 2004).
"Common diving-petrel." Australian Government, Department of the Environment and Heritage. http://www.antdiv.gov.au/default.asp?casid=1552 (accessed on May 26, 2004).