Annex II

A Brief Description of Species Monitored by the CCAMLR Ecosystem Monitoring Program

Antarctic fur seal (Arctocephalus gazella)

Distribution
Antarctic fur seals breed on most sub-Antarctic islands in the Atlantic and Indian Ocean sectors from South Georgia to Macquarie Island, but ~95% of the world’s population is found at South Georgia. They also breed in small numbers at the South Sandwich, South Orkney and South Shetland Islands and at a few sites on the northern Antarctic Peninsula. The total population at South Georgia is approaching 3 million individuals. Although males generally move south from South Georgia towards the ice edge after breeding, some are present at South Georgia all winter. Females disperse after breeding but their distribution at sea is unknown.

Size and age
Adult males are up to 2 m long, weigh from 120 to 220 kg, and live for up to 15 years. Sexual maturity is reached at around age 4, but males normally do not breed until 6 to 7 years old. Adult females are up to 1.5 m long, weigh from 25 to 60 kg, and live for up to 20 years. They mature from 2 to 4 years of age and produce a single pup in most years.

Biology
In the Atlantic Ocean sector, Antarctic fur seals feed on krill (E. superba), but also take fish, such as mackerel icefish and lanternfish (Myctophidae). In the Indian Ocean sector, lanternfish are their main prey. They give birth between late November and early January, when dominant males hold territories in the breeding colonies. Females mate again five to seven days after parturition and thereafter make regular four- to six-day trips to sea to find food. Lactation lasts four months and pups are weaned in early April.

Exploitation
The species was nearly exterminated by sealing in the 19th and early 20th centuries. By 1920 the species was considered extinct, but during the 1920s sightings were reported from South Georgia. By 1957 a colony had become established. During the 1960s the population growth rate was close to the biological maximum (18% per annum); by the 1980s it had declined to 10% per annum.

Status
Antarctic fur seal numbers are increasing throughout the Southern Ocean. Their increase in some locations may be driven by emigration from South Georgia. Entanglement in marine debris is thought to be the only current threat to this species.

Crabeater seal (Lobodon carcinophagus)

Distribution
Although this species is distributed circum-Antarctic and within the pack-ice zone, it is especially abundant towards the marginal-ice zone. Individuals have been shown to move over many thousands of kilometres and evidence suggests that crabeater seals in the Antarctic belong to a single population, with little or no segregation between residual pack-ice zones. These seals are most commonly solitary, but are sometimes found in groups of 50 to 100 swimming close together.

Size and age
Crabeater seals reach 2.6 m in length, weigh up to 200–300 kg and may live for over 40 years. Sexual maturity of both males and females is at 4 to 6 years of age.

Biology
The main prey is krill with a small proportion of fish, such as Antarctic silverfish (Pleuragramma antarcticum). Their diving behaviour is consistent with feeding on krill in the top 50 to 60 m. The pups are born during September and October. Lactation lasts 15 to 20 days and, towards weaning, mothers mate with an attending male.

Exploitation
In the past, small numbers of crabeater seals have been exploited as food for sledge dogs and, occasionally, as part of a limited commercial harvest. There is no current exploitation.

Status
Estimates of the number of crabeater seals vary from 7 to 30 million. A figure of 10 to 12 million is most likely, but a more precise estimate is required to discern trends in the size of the population. There are no known threats to crabeater seals at present.

Adélie penguin (Pygoscelis adeliae)

Distribution
This species’ breeding distribution is circum-Antarctic, with concentrations in the Ross Sea, the Antarctic Peninsula and associated island groups, as far north as the South Sandwich Islands. Outside the breeding season this penguin is mainly confined to the pack-ice and marginal-ice zones. The lowest estimate of the total breeding population is about 2.5 million pairs.

Size
Overall length 70 cm, weight about 4 to 5 kg.

Biology
The breeding season starts in October and ends in February. The eggs are incubated for 35 days (two long shifts by each parent) and the chicks reared for 50 to 60 days. The birds usually moult on the sea-ice before dispersing into the pack-ice and marginal-ice zones for winter. On average, breeding starts at age 5 (female) to 6 (male), and can continue for the next 8 to 10 seasons. They have high fidelity to nest site, colony and place of birth. Juveniles usually first return to their birth site at 2 years old.

The penguin’s diet mainly consists of crustaceans (krill) but fish, especially Antarctic silverfish, may be important at colonies on the Antarctic continent. Of crustaceans, E. superba dominates the diet of birds breeding in the Peninsula region. In the Ross Sea, E. crystallorophias is dominant; at other continental sites both Euphausia species are taken, proportions varying substantially within and between years.

Status
In the Ross Sea, colonies declined until 1970, remained stable in the 1970s and increased significantly in the 1980s, but are currently decreasing. At other continental sites more limited data suggest stability or slight increase from the 1950s to the 1980s, with some evidence of local increases in the 1990s. In the Peninsula region, colonies increased steadily from the 1940s to the 1970s, remaining stable (with considerable fluctuation) during the 1980s, but most have decreased in the 1990s.

Chinstrap penguin (P. antarctica)

Distribution
Breeding is virtually confined to the northern Antarctic Peninsula and associated island groups (particularly the South Sandwich Islands), with the northern limit at South Georgia. The only other breeding sites are Peter I, Balleny and Heard Islands; their current status is unclear. The world’s breeding population is estimated at 7.5 million pairs – but this assumes 5 million pairs at the South Sandwich Islands, which have not been adequately surveyed.

Size
Their overall length is 70 cm, and weight about 4 kg.

Biology
The duration and chronology of the breeding cycle are similar to those of the Ad?ie penguin, but are shifted one month later, i.e. late October–early November to late February–early March. After breeding, chinstrap penguins moult (usually on land, often near breeding sites) and then disperse, mainly to open-water areas at the edge of the marginal-ice zone. Age of breeding, site fidelity and survival rates have not been recorded, but are probably similar to the Ad?ie penguins’. In the breeding season they eat krill almost exclusively.

Status
Peninsula populations increased rapidly from the 1940s to the 1970s; up to 1990 there were substantial fluctuations, but the populations were basically stable. However, there is evidence of recent population declines at many sites.

Gentoo penguin (P. papua)

Distribution
Widespread as a breeding species at sub-Antarctic islands in the South Atlantic and South Indian Oceans and at Macquarie Island, the gentoo penguin is also widespread on the Peninsula (and associated island groups) south to 64?S. The total world breeding population is about 317 000 pairs (33% at South Georgia, 21% at the Falkland/Malvinas Islands, 12% at Kerguelen).

Size
This species’ overall length is 75 cm, and weight 5 to 7 kg.

Biology
At most sites most of the population probably remains near the breeding site year-round. The start of breeding is very variable between years and sites, being earliest (June) and longest at Indian Ocean sites; it more typically starts later (October) and is more synchronised, for example, at South Georgia and the South Shetland Islands. Incubation lasts 35 days (in shifts of only one to three days) and chick-rearing lasts from 80 to 120 days. After breeding they moult ashore, often near the breeding colony. Breeding can start as early as 2 years (mean 3 years) of age, with 8 to 10 further breeding seasons on average. Site and mate fidelity are strong but colonies are prone to shift location periodically. In the Atlantic Ocean sector the diet mainly comprises E. superba, less often also substantial quantities of fish, particularly mackerel icefish (C. gunnari) and nototheniids. In the Indian Ocean, fish (especially myctophids and nototheniids) dominate, with E. vallentinii (and Nauticaris marionensis at Marion Island) the main crustaceans.

Status
At the Falkland/Malvinas Islands and South Georgia, numbers have decreased by 20 to 40% over the last 20 years. Some Peninsula populations have increased by similar percentages over the last 10 to 15 years. Populations, especially in the Indian Ocean, are very susceptible to disturbance by humans.

Macaroni penguin (Eudyptes chrysolophus)

Distribution
This species is a widespread breeder, usually in very large colonies, at sub-Antarctic and similar islands in the Atlantic and Indian Oceans from Chile to Heard Island; its southern limit is effectively in the Elephant Island group (South Shetland Islands). The world breeding population is estimated at about 9 million pairs, but reliable recent data are lacking for many sites. Its strongholds, in descending order, are South Georgia and Crozet, Kerguelen, Heard and McDonald Islands. Outside the breeding season, its distribution is virtually unknown.

Size
The macaroni penguin has an overall length of 70 cm, and weighs 3 to 4 kg. Markedly sexually dimorphic, males are about 10% larger than females.

Biology
This penguin returns to colonies in late October–early November. Incubation (35 days) and brooding (about 20 days) are done in three long shifts (with the middle one by the female). Chick-rearing takes from 55 to 70 days. The adults then spend from 15 to 30 days at sea before returning to the breeding colony for 20 days to moult and fast. On average, it first breeds at 8 years of age, showing high site and mate fidelity. Juveniles of all ages return to shore to moult, often to their natal colony. They eat mainly, sometimes exclusively, euphausiid crustaceans, typically E. superba, (sometimes with Thysanoessa spp.) or E. vallentinii in the Indian Ocean. Occasionally tiny fish (mainly myctophids), particularly towards the end of chick-rearing, and the amphipod T. gaudichaudii are taken in some quantity.

Status
Few data exist. Numbers increased in the Kerguelen Islands from 1962 to 1985; there is no subsequent information. At South Georgia, numbers probably increased between the 1950s and the 1970s; since 1977 there has been a substantial decline, perhaps by up to 50%.

Black-browed albatross (Diomedea melanophrys)

Distribution
The black-browed albatross breeds at South Georgia, Crozet, Kerguelen, Heard, Macquarie and Antipodes Islands; also in the Falkland/Malvinas Islands and South America. The world population numbers about 680 000 pairs, 86% in the Falkland/Malvinas Islands, 10% at South Georgia. In the breeding season, the birds are mainly associated with continental shelves and adjacent frontal zones. Non-breeders and immatures are widely distributed between 40 and 65?S. Breeding birds migrate north in winter, especially to coastal waters around South America, South Africa and Australia.

Size
This albatross stands about 50 cm tall (overall length about 90 cm), with a wing span up to 250 cm. It weighs about 4 kg.

Biology
In September–October, the adults return to their colonies and lay in mid–late October. The eggs are incubated for 68 days and the chicks fledge in April–May after another 115 days. Adults show very high site and mate fidelity; juveniles show high fidelity to their birth site. This bird breeds first, on average, at about 10 years of age. Its diet is a varied mixture of crustaceans, fish and cephalopods. At South Georgia, fish (usually P. guntheri, P. georgianus and C. gunnari); squid (mainly ommastrephids M. hyadesi); and crustaceans (chiefly E. superba). In the Indian Ocean, krill are absent, crustaceans rare and fish predominant, with ommastrephid squid also important.

Status
The Falkland/Malvinas Islands population increased rapidly during the 1980s (in concert with a major offal-producing fishery), but is now virtually stable. The population at Bird Island, South Georgia, fluctuated but was fairly stable until the late-1980s; since 1989 it has decreased by about 7% a year, with reductions in adult survival and, especially, juvenile recruitment. Interactions in the non-breeding season with longline fisheries, especially those for toothfish around South Georgia and elsewhere, are believed to be the most likely cause. The Kerguelen population is also decreasing, and at-sea abundance in the Prydz Bay region decreased significantly between 1981 and 1993.

Antarctic petrel (Thalassoica antarctica)

Distribution
Breeding is confined to the Antarctic continent, all but one of the 35 known colonies being in eastern Antarctica. Colonies are often very large, and many are on mountain tops well inland. The birds feed mainly in open-water areas near ice. Outside the breeding season they are mainly associated with polynyas in pack-ice and with the marginal-ice zone. The world population is unknown, but rough estimates are of several million birds.

Size
Its overall length is 45 cm, wing span 100 cm, and weight about 700 g.

Biology
Birds arrive at the colony in early October and lay in mid-November. The chicks fledge in early March after incubation and chick-rearing periods of about 45 days each. Demography is largely unknown. In the breeding season the birds eat mainly krill, but substantial amounts of squid and fish (especially Pleuragramma) have also been recorded.

Status
No data available.

Cape petrel (Daption capense)

Distribution
The cape petrel breeds at all sub-Antarctic islands (north to the Chatham Islands and New Zealand), around the Antarctic continent (mainly in the Indian Ocean sector) and is widespread in the northern Antarctic Peninsula and associated island groups. Breeding birds are mainly found on shelf waters during the breeding season, and there are few records north of 50?S. In March, they make a northward migration, with a substantial proportion of the population wintering north to 20?S off the coasts of South America, South Africa and Australia. The world population is unknown, but undoubtedly numbers several million birds.

Size
The adult birds have an overall length of 40 cm, a wing span of 85 cm, and weigh about 450 g.

Biology
Birds return to the breeding colony in September–October and lay in November–December. Their chicks fledge in March after 45 days’ incubation and about 50 days of rearing. The cape petrel first breeds on average at 6 years of age. Its diet in the breeding season is mainly euphausiids – E. superba in the Atlantic Ocean sector, usually mixed with E. vallentini and often smaller amounts of fish, typically P. antarcticum in the Indo-Australian sector.

Status
In the Atlantic Ocean sector, numbers increased markedly during and after the whaling era; they may have colonised South Georgia early in this period. Populations are probably stable nowadays.