Black-Browed Albatross

## Description

The black-browed albatross (Thalassarche melanophris ), also known as the black-browed mollymawk, is a large seabird of the albatross family Diomedeidae; it is the most widespread and common member of its family.

## Appearance

The Black-browed albatross is a member of the albatross family Diomedeidae, the ‘tube-noses’, related to shearwaters, petrels, and fulmars. It is the most common and widespread albatross. The name for this large seabird comes from the dark black plumage above its eyes. Albatrosses are true marine birds, traversing the oceans in the southern hemisphere, returning to land only to breed. They are similar to the gray-headed albatross but the latter has a wholly dark bill and more complete dark markings on the head.

## Distribution

The Black-browed albatross is found anywhere in the south Atlantic and circumpolar in the southern hemisphere. It can travel further to the north with cold currents. During September and October, these birds breed on south Atlantic islands such as South Georgia and the Falkland Islands, South Sandwich, and the Cape Horn islands. These are marine, pelagic birds but they do commonly come inshore, typically moving toward the shore during violent weather. Breeding grounds are typically on steep slopes with cliff terraces, tussock grass, or level ground.

## Behavior

Black-browed albatrosses typically are solitary at sea, except when there is a large feeding opportunity. They forage both day and night, according to the prey species. They gather during the breeding season in nesting colonies that can number over 180,000 pairs. They are very mobile birds and can travel 500 to 3,000 km to forage. They are often seen hundreds of miles offshore following a ship, simply gliding behind it. This species only establishes territory during the breeding season. Breeding pairs will not permit another individual to come within 1.5 m of their nest. They are generally silent birds, but with breeding colonies will make rapid grunting noises. They will also make noises by beak-clapping. Breeding pairs communicate through courtship behaviors like allopreening and beak touching. Black-browed albatrosses, like all birds, perceive their environment through visual, auditory, and tactile, as well as chemical stimuli.

## Diet

Black-browed albatrosses are carnivores (piscivores) and scavengers; they mainly eat crustaceans and fish but will also consume squid, carrion, and fishery discards.

## Reproduction

This species is monogamous, and Black-browed albatrosses often mate for life. A pair will often engage in rituals of feeding each other, using stereotyped postures while facing each other. Mutual preening is also performed, mainly to the head, and rubbing each other’s bills, as well as dances and calls. The breeding season begins in September or October and runs until April. The birds form colonies during the breeding season. They build their nests from mud, grass, seaweed, and guano, on a volcano-shaped mound. The single egg is incubated for 71 days. The chick is brooded during its first weeks and fledges at about 120 days old. Both parents feed and guard the downy young until it becomes independent when it fledges. These birds are reproductively mature around 7-9 years of age but mating activity usually begins at 11 years old.

## Population

### Population threats

The greatest threat to these birds seems to be an increase in by-catch due to long-line sea fishing practices in the southern oceans, particularly off the coasts of Argentina and Uruguay along the Patagonian shelf. Further threats include natural disasters (fires, floods, and volcanic activity), disruption of prey populations, ingesting plastic, pollution, habitat destruction, and disease.

### Population number

According to IUCN’s Red List, the total size of the Black-browed albatross population is 700,000 pairs (i.e. 1,400,000 mature individuals), roughly equating to 2,100,000 individuals. This includes: Falkland Islands (Islas Malvinas) - 475,500-535,000 pairs; Chile - 55,000 pairs on Diego Ramirez; 58,000 pairs on Ildefonso; 15,500 pairs on Diego de Almagro; South Georgia (Georgias del Sur) - 56,000 pairs. There are an estimated 5,800 pairs in other populations (Antipodes, Campbell, Heard and MacDonald, Crozet, Kerguelen, Macquarie, Snares). Overall, currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are increasing.

### Ecological niche

Being piscivores, these birds may likely affect fish populations in their range.

## Fun Facts for Kids

Black-browed albatrosses locate krill, their favorite food, using a method called local enhancement, i.e. when they see another forager feeding successfully, they join in.

Black-browed albatrosses tolerate other bird species close to their nests but another albatross may not come closer than around one and a half meters.

A group of albatrosses is called a "flight", "rookery", or "weight" of albatrosses.

On landing, a Black-browed albatross will lower its webbed feet to use as brakes to slow down.

Black-browed albatrosses produce oil in their stomachs to use as nutrients during long flights or to spit at attackers.

These birds possess a gland above their nasal passage that produces a saline solution that gets rid of the salt they swallow when diving for food in the sea

The flying heart rate of a Black-browed albatross is almost the same when it is resting, due to its excellent gliding ability, thanks to the size of its wings.

## References

https://animalia.bio/black-browed-albatross