The Giant Petrels of King George Island
Antarctica trips take you to what is undoubtedly one of the world’s greatest birding hotspots. Nowhere else in the world can you find penguins, storm petrels, skuas, and kelp gulls all within the same binocular glance. No matter your degree of interest in birds, or what level of experience you have with birding, there’s always a great amount of admiration when seeing them for the first time in their natural habitat. There’s one species in particular that you may encounter that stands a few inches higher than the others, lumbering awkwardly around the beach as if it had never walked on ground before. On windy days, they can be seen cruising around with a wingspan up to seven feet! With piercing grey eyes and a sharp beak equipped with a small tube, the giant petrel is the king of the beach, and an impressive sight to behold.
The Tube Noses of Antarctica
Also referred to as “stinkers” for their overpowering odor, the giant petrels are one of the largest birds encountered in the southern hemisphere. Currently, there are two different recognized species of giant petrels, the northern and southern giant petrels. The two species are virtually indistinguishable from one another, and are often grouped into one umbrella species of “giant petrel”. Several different color variations or “morphs” are recognized within the two species, and can vary from complete white to a dark grey.
Due to the fact that the giant petrels spend most of their life at sea away from any source of fresh water, accommodations must be made. On top of their beak sits two tube-shaped nostrils that are responsible for filtering out salt from seawater. This special adaptation allows the petrels to acquire fresh, filtered water from their salty environment. Other groups of birds, including shearwaters, fulmars, albatross, storm petrels, and diving petrels also possess this feature, and are casually referred to as just “tubenoses”.
Giant petrels are very much solitary creatures. They spend months on end feeding out at sea on their own, and seldom encounter members of their own species during this time. When summer arrives in October, it’s time migrate to the circumpolar regions of Antarctica to breed.
The giant petrels love their privacy, and will nest several hundred meters away from one another in colonies that have been utilized for many, many generations. Constructing a nest is the easiest part of this process, and usually only requires moving a few stones around to correctly accommodate their large bodies and long legs. Several weeks after establishing a nesting space, the eggs begin to arrive. At an impressive eight inches in diameter, a giant petrel’s egg can easily be mistaken for a dinosaur egg. Oddly enough, the giant petrel only lays one egg per year, making it important for the parents to remain as vigilant and as protective as possible. Still, the parents are extremely sensitive to disturbance of any kind, and will abandon their egg if they sense even the slightest amount of danger. Evolution has taught them that their own survival is more important than their unhatched egg as far as the future of their species is concerned. The adults can always return next year and try nesting again, but risking their own lives to defend a single egg is just not in their nature.
Working with Petrels
However sensitive they may be, the Austral summer period from October to March is the only practical time that scientists have been able to study the petrels, and learn how to better conserve and manage their populations around Antarctica. At the beginning of the breeding season, the petrels are monitored at a safe distance through binoculars and high-powered spotting scopes so as to not scare them off their nests. A census of their colonies is taken, mapped, and compared to historical records.
Occasionally, a nesting giant petrel colony will overlap with a penguin colony, making disturbance from penguins and humans a difficult matter. When it’s absolutely imperative that the scientists need to approach the petrel colonies for the purposes of penguin monitoring, it’s best to move slowly, and avoid any kind of close contact. They’ll be keeping a sharp eye out all the while, and may even emit a low “uuuurrr” sound if they’re feeling especially threatened. Once the eggs are laid, the petrels will seldom be seen away from their nest. They’re devoted parents, and keeping the large egg warm in a cold environment is important.
When the chicks begin to poke their tiny tubenoses out of their eggs, it’s time for the parents to begin feeding. It’s an around the clock task, and requires lots of time out at sea catching fish, looking for dead seals that may wash up on the beaches, and cruising penguin colonies for unattended eggs or chicks. The petrel chicks experience some of the finest dining in Antarctica!
When disturbed in any way, the chicks have their own line of defense, referred to as “gakking”, which is the sound they make as they projectile vomit all over a predator, or worse yet, a scientist that dares come too close. It’s a horrible smell, and is composed of digestive fluid, and the remains of whatever sea creature their parents last stuffed into their mouths. Clothing and gakking do not mix well, and most commonly result in immediate disposal of anything that has touched the horrible brew in any way. Unfortunately for the scientists, brief contact with the chicks must be made, all in the name of wildlife conservation. As chicks, the giant petrels are fitted with a unique, metal band that permanently sits around their leg. The number on the metal bands corresponds to the year they were banded. Giant petrels banded as chicks may return to these breeding grounds in following years. Every year when the scientists return to collect data, they try to read these band codes and determine which individuals have returned from previous years to rear young of their own.
From 1997 and 1998, thousands of giant petrels were killed in illegal longline fishing operations in the Southern Ocean. The long lines were meant for Patagonian tooth fish, but instead caught upwards of 4,000 giant petrels and countless other species of sea birds and marine mammals. This method of fishing has since been highly regulated, and resulted in the regeneration of the giant petrel’s population. Although they are currently classified a species of least concern, an increase in marine plastics and other trash pose as a constant threat to their population.
Where to Find Giant Petrels
Luckily, giant petrels have seen an increase in their population over the past 20 years since the increased regulation in longline fishing, and can be found in abundant numbers throughout their range. During the breeding season, they’re most likely to be found all throughout the coastal areas of Antarctica and on sub Antarctic islands. If you’re travelling through the Drake Passage to get to Antarctica, make sure to keep those binoculars out! Giant petrels and many other unique seabirds are plentiful in this area. They can frequently be seen catching strong gusts of wind, or lazing about in the water looking for dead fish.