Petrel

The petrel is the hero of many lyrical poems and songs, a bird that invariably accompanies sea vessels along with seagulls. These giants are dangerous predators and dexterous hunters that can soar over the surface of the water for days on end.

Origin of the species and description

Photo: Burevestnik

Photo: Petrel

The petrel is a sea bird of the petrel order. In fact, the order includes many species of birds that are grouped under this name. Common to all species is their physiology, which allows them to soar over water for a long time and feed from the ocean. The main distinguishing feature is the tubes in the beak through which the salt comes out.

Petrels need a lot of water, but live over salty seas and oceans, where there is no source of fresh water for a huge number of kilometers. Therefore, they, like penguins, have adapted to drink salt water. Salt water passes through a “filter” in their beak and is excreted as salt through tubes.

Video: Petrel

Petrels vary in size and coloration, but are mostly very large, massive birds with a wingspan of up to 1m. It is the second largest bird after the albatross. Petrels have their roots in the Oligocene – about 30 million years ago, although some remains of physiologically similar birds have been found as early as the Cretaceous – date back to 70 million years old.

It was a common ancestor of petrels, albatrosses and storm petrels , but the petrels were the first to stand out. Most of the progenitors of the petrel lived in the Northern Hemisphere, including in the northern part of the Atlantic Ocean. At the moment, there are no petrels there, or they fly there by chance, being in an active search for food.

Appearance and Features

Photo: What a petrel looks like

Photo: What a petrel looks like

With all its appearance, the petrel testifies to the ability to soar in the air for a long time over the expanses of the ocean. They have a short body, strong wings and small paws. The feather cover of petrels is dense, which does not allow birds to freeze under gusts of wind and get wet from salt water and rain.

Interesting fact: The paws of petrels are so small and located so close to the tail that they cannot stand on them – they have to rely on their wings and chest. The beaks of these birds are always slightly pointed, curved at the end – this allows the birds to effectively hold slippery fish.

Depending on the species, petrels differ in appearance, including size.

The most common species are as follows:

  • northern giant petrel. This is the largest bird of the petrel family;
  • southern giant petrel. This bird is inferior in size to its northern relative;
  • Antarctic petrel. These are medium-sized brown birds;
  • cape petrel. They are also called Cape doves. This is a medium-sized bright bird, reaching a length of 36 cm;
  • snow petrel. This is a small species up to 30 cm long;
  • blue petrel. Also a medium-sized bird with a wingspan of up to 70 cm.

These are just some of the petrel species. The family includes more than 70 officially recognized species.

Where does the petrel live?

Photo: Petrel in flight

Photo: Petrel in flight

The petrel spends almost its entire life hovering over the oceans and seas. Its wings are adapted to hold the petrel’s body for days, tacking on gusts of air. It is difficult to name a certain range of petrels, since, unlike albatrosses, they live in both the Southern and Northern hemispheres. The northern giant petrel can be found in the Atlantic, Pacific, and Indian oceans. The nesting place is the South Georgia Islands.

The southern giant petrel lives in the same waters, but nests only near Antarctica. Antarctic and snow petrels also live there. Cape and blue petrels prefer subantarctic climates, nesting at Cape Horn. The Wetland petrel lives only off the coast of New Zealand. Lesser, variegated and gray petrels nest in the Atlantic. The range of the slender-billed petrel is also limited – exclusively to Tasmania off the coast of Australia.

Petrels do not need land as a permanent habitat. They can take short breaks right on the water, have the ability to sleep right in the air, simply relying on spread wings and the wind. Petrels often land on ships and barges to rest – this is how this species was discovered by sailors. Petrels nest only during the breeding season, when they need to lay their eggs and take care of their offspring. They always choose the same places for nesting.

Interesting fact: A petrel born on a certain island will always breed only there.

Now you know where the petrel is found. Let’s see what he eats.

What does a petrel eat?

Photo: Petrel Bird

Photo: Petrel Bird

The petrel is a bird of prey. To constantly maintain energy in a huge body that is in flight for days, the petrel needs a huge amount of protein. Therefore, in addition to small fish, its diet includes all kinds of crustaceans and cephalopods – especially squids. Sometimes petrels chase fishing boats. There they can not only relax, but also profit from fish from the nets. Also, petrels willingly eat carrion, steal food from other birds of prey and mammals.

Especially large species of petrels are able to hunt on land. They mainly destroy the nests of gulls, penguins and other birds by eating eggs. But it happens that they even attack penguin chicks or fur seal cubs. It doesn’t cost anything for a large petrel to peck at a pinniped calf while the mother is on the hunt.

Fun fact: Even though crested penguins are small birds, petrels do not touch them due to their lively nature.

A special item in the diet of petrels is krill. Thanks to salt water filtering features in their beaks, petrels glide right at the surface of the water, scoop up water in their beaks, filter it, and ingest nutritious krill as they go. This allows them to survive even in times of famine. Petrels actively hunt only at night. Tightly pressing the wings to the body, they, like a rocket, plunge into the water in the place where they noticed a flock of fish. They quickly catch several fish, swallow them right under the water and swim out with a fish in their beak. The maximum depth to which these birds dive is 8 meters.

Peculiarities of character and lifestyle

Photo: Burevestnik in Russia

Photo: Burevestnik in Russia

The bird spends most of its time flying over water. They fly in small flocks – 5-7 individuals each. So it is easier for them to look for prey under water and escape from possible dangers. Large groups of petrels congregate over a school of fish, a vessel, or other prey. Because of this, some sailors consider them “sea vultures”. Sailors know about the amazing ability of the petrel to feel the approach of a storm. In calm, windless and dry weather, these birds soar peacefully in the sky, looking for prey. But if a thunderstorm and a strong wind are approaching, the petrels descend low to the water and scream. Thanks to this behavioral feature, petrels got their name.

Petrels are aggressive and cunning birds. Descending on ships in small groups, they share duties: some individuals distract sailors by pretending to steal fish, while other petrels are really engaged in stealing and feeding. On fishing barges, petrels can fill their belly well. But there is a downside, because of which petrels do not like to go down on ships. Not only are their paws not adapted for normal walking, but they also cannot take off, landing on too low a surface.

The fact is that with such a ratio of wingspan and body size, you can take off only by diving from a great height and catching gusts of wind. Therefore, petrels willingly fly into storms when they can safely maneuver between numerous wind gusts. Petrel aggression extends to other animals as well. Having noticed a baby fur seal or a penguin as prey, they may not wait until the parent goes hunting, but attack openly. Usually, the maneuverability of a penguin or fur seal is not enough to drive away the petrel, and he kills the cub, feeds on it in front of the parent.

Social structure and reproduction

Photo: Gray Shearwater

Photo: Gray petrel

Sexual dimorphism in petrels is not expressed. In some species, the female is slightly smaller than the male, but sometimes there is not even such a difference. Therefore, the petrels themselves determine the female or male by certain sound signals and body movements.

Birds unite in large colonies, where they look for a mate. Such colonies can reach a million individuals. This makes it difficult to find a good nest site, so petrels fight a lot among themselves for comfortable territory. Fights between petrels continue for the right to mate with a female. It is extremely rare for petrels to form stable pairs that do not break up for several years.

After the female has chosen a male for herself, mating games begin. The male brings gifts to the female — stones and branches for nest building. Together they create a nest, after which mating occurs and one egg is laid. The female leaves the egg in the care of the male, and she flies away for a month and feeds in the sea. By the time she returns, the chick has already hatched, so she begins to feed it with overcooked food from their special crop. The father may fly to the sea to feed, but regularly returns to feed the female and the growing chick.

Leaving him alone is dangerous – other petrels for unreasonable reasons can kill the cub. Small petrels mature by two months, large ones by four. Adult chicks fly away from the nest and forget their parents. In total, these birds live for at least 15 years, but the longest lived in captivity lived up to 50.

Natural enemies of the petrel

Photo: What a petrel looks like

Photo: What a petrel looks like

Petrels are large birds that can stand up for themselves, so they do not have many natural enemies. The south polar skua often destroys nests, eats eggs and immature chicks if the parents have gone somewhere. Also, these birds compete with petrels for food, so serious skirmishes can occur between them.

Rats and cats introduced into the nesting area also pose a danger to nests and chicks. But baby petrels also have their own means of protection. Feeling fear, the chick shoots a jet of foul-smelling liquid from its mouth, which instantly scares off any predators. This liquid is oily, hard to wash off and smells for a long time, which complicates the further hunting of a possible predator.

Fun Fact: As with penguins, gender confusion can sometimes lead to same-sex pairings in these birds.

Small petrel species may also be threatened by some fish and sea lions. They may be attacked by sharks or other large marine life when the petrel dives into the water for prey or when simply floating on the waves. Under water, these birds are defenseless, so they are easy prey.

Species population and status

Photo: Petrel Bird

Photo: Petrel Bird

Petrels are distinguished by their huge numbers. Being predators with large sizes, they do not arouse interest in other birds of prey and animals. Having no commercial value, they have never been the object of targeted hunting by people. The number of petrels in the Atlantic alone is about 3 million. The Pacific Ocean is inhabited by about 4 million individuals. The Antarctic petrel has approximately 20 million individuals in total. The population is stable.

However, some species are classified as rare, although they are not listed in the Red Book.

These are the following species:

  • Balearic petrel;
  • pink-footed petrel;
  • white typhoon;
  • Madeiran typhoon;
  • Hawaiian typhoon.

The decrease in numbers is caused solely by anthropogenic factors that have several reasons, one of which is pollution of the oceans. Petrels often dip into oil slicks, mistaking them for schools of fish, which is why they soon die of poisoning. So birds can get entangled in plastic while swimming and die, unable to float or take off. And also, mass fishing. Fish are caught on a commercial scale in the habitats of petrels. They are deprived of food supply, which is why they need long migrations in search of food. This also affects the population.

The petrel is a giant bird, second in size only to the albatross. Their size, lifestyle and character traits have allowed them to become one of the most numerous species of birds. They still actively accompany ships on sea voyages and notify sailors of approaching storms.

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