The Southern Ocean and South Pacific Region

The Region comprises three sub-regions (FAO Statistical Areas) with very different characteristics. The South Pacific includes the vast and virtually unpopulated Southern Ocean surrounding the Antarctic. It has the world’s largest fisheries off Peru and Chile and some of the world’s best managed fisheries in Australia and New Zealand. The Region has over 27% of the world’s ocean area and over 98% of the Region’s total area of 91 million km2 is ‘open ocean’. The Region contains less than 5% of the global continental shelf area and only a fraction of this area is covered by three large marine ecosystems (the New Zealand Shelf, the Humboldt Current and the Antarctic large marine ecosystems (LMEs). The Humboldt Current System (HCS) is the world’s largest upwelling which provides nutrients for the world’s largest fisheries. The Region also has a high number of seamounts. The marine capture fisheries of the Region produce over 13 million tons annually and an expanding aquaculture industry produces over 1.5 million tons. Peru’s anchoveta fishery provides about half the world’s supply of fish meal and oil, key ingredients of animal and fish feeds. El Niño Southern Oscillations (ENSOs), known more generally as El Niños, can substantially change the species composition of the key small pelagic catches (anchovy, sardine, horse mackerel and jack mackerel) causing production to fluctuate from about 4-8 million tons. Partly due to the lack of upwelling and shelf areas, fisheries production in the Southern Ocean and Area 81 is relatively small but supports economically important commercial and recreational fisheries and aquaculture in New Zealand and in New South Wales (Australia). Krill remains a major underexploited resource, but is also a keystone species in the Antarctic food web. The Region is home to numerous endangered species of whales, seals and seabirds and has a high number of seamounts, vulnerable ecosystems fished for high-value species such as orange roughy.

The Southern Ocean and South Pacific Region

The Region comprises three sub-regions (FAO Statistical Areas) with very different characteristics. The South Pacific includes the vast and virtually unpopulated Southern Ocean surrounding the Antarctic. It has the world’s largest fisheries off Peru and Chile and some of the world’s best managed fisheries in Australia and New Zealand. The Region has over 27% of the world’s ocean area and over 98% of the Region’s total area of 91 million km2 is ‘open ocean’. The Region contains less than 5% of the global continental shelf area and only a fraction of this area is covered by three large marine ecosystems (the New Zealand Shelf, the Humboldt Current and the Antarctic large marine ecosystems (LMEs). The Humboldt Current System (HCS) is the world’s largest upwelling which provides nutrients for the world’s largest fisheries. The Region also has a high number of seamounts. The marine capture fisheries of the Region produce over 13 million tons annually and an expanding aquaculture industry produces over 1.5 million tons. Peru’s anchoveta fishery provides about half the world’s supply of fish meal and oil, key ingredients of animal and fish feeds. El Niño Southern Oscillations (ENSOs), known more generally as El Niños, can substantially change the species composition of the key small pelagic catches (anchovy, sardine, horse mackerel and jack mackerel) causing production to fluctuate from about 4-8 million tons. Partly due to the lack of upwelling and shelf areas, fisheries production in the Southern Ocean and Area 81 is relatively small but supports economically important commercial and recreational fisheries and aquaculture in New Zealand and in New South Wales (Australia). Krill remains a major underexploited resource, but is also a keystone species in the Antarctic food web. The Region is home to numerous endangered species of whales, seals and seabirds and has a high number of seamounts, vulnerable ecosystems fished for high-value species such as orange roughy.

Congruent trends in long-term zooplankton decline in the north-east Atlantic and basking shark (Cetorhinus maximus ) fishery catches off west Ireland

Trends in basking shark (Cetorhinus maximus) fishery catches off Achill Island, west Ireland between 1949 and 1975 were examined in relation to zooplankton (total copepod) abundance in four adjacent sea areas over a 27-year period. The numbers of basking sharks caught and copepod abundance showed downward trends and were positively correlated (r-value range, 0.44–0.74). A possible explanation for the downward trend in shark catches was that progressively fewer basking sharks occurred there between 1956 and 1975 because fewer copepods, their food resource, occurred near the surface off west Ireland over the same period. We suggest that the decline in basking sharks may have been due to a distributional shift of sharks to more productive areas, rather than a highly philopatric, localized stock that was over-exploited.

Genetic structure of whiting (Merlangius merlangus) in the north east Atlantic and adjacent waters

Accurate identification of stock boundaries is essential for efficient fisheries management, hence the present study focused on the genetic structure of whiting. To this aim, 488 individuals collected from the southern Bay of Biscay to the southern Norwegian coast were genotyped using seven microsatellites. A low level of genetic structuring was detected in Atlantic waters since only the Bay of Biscay differentiated from more northern samples. The lack of genetic structure along the western margin of the British Isles is consistent with a high level of passive transport of pelagic eggs and larvae due to the combined influence of the North Atlantic Current and the Shelf Edge Current. High levels of dispersal could also occur between the western British Isles and the North Sea through both the branching of the North Atlantic Current into the northern North Sea and from the residual current flowing from the English Channel to the Southern Bight. In contrast, a significant genetic structure was identified within the North Sea, and this may be associated with the complex oceanography of this basin and retention systems reducing larval dispersal. In addition, considering also genetic, phenotypic and tag-recapture data collected on whiting, a learned homing behaviour of adults toward spawning areas may be hypothesised.

Interannual variability of marine zooplankton and their environments: Within- and between-region comparisons

The work highlights the first Global Comparison of Zooplankton Time Series. ► Variation of the peak in abundance is affected by annual temperature anomalies. ► Results show no global-scale synchrony in zooplankton time-series. ► There are spatial autocorrelations over substantial distances (1000–3000 km). ► There remains considerable uncertainty about the relative causes of shifts in distributions.

A review of some common Indo-Malayan and western Pacific species of Chthamalus barnacles (Crustacea: Cirripedia)

The type specimens of the common tropical intertidal barnacles Chthamalus malayensis and C. moro, were re-investigated and compared with other specimens of Chthamalus from the Indian Ocean, Indo-Malaya, northern Australia, Vietnam, China and the western Pacific, using ‘arthropodal’ as well as shell characters. Chthamalus malayensis occurs widely in Indo-Malayan and tropical Australian waters. It ranges westwards in the Indian Ocean to East Africa and northwards in the Pacific to Vietnam, China and the Ryukyu Islands. Chthamalus malayensis has the arthropodal characters attributed to it by Pope (1965); conical spines on cirrus 1 and serrate setae with basal guards on cirrus 2. Chthamalus moro is currently fully validated only for the Philippines, Indonesia, Taiwan, the Xisha (Paracel) Islands, the Ryukyu Islands, the Mariana Islands, the Caroline Islands, Fiji and Samoa. It is a small species of the ‘challengeri’ subgroup, lacking conical spines on cirrus 1 and bearing pectinate setae without basal guards on cirrus 2. It may be a ‘relict’ insular species. Chthamalus challengeri also lacks conical spines on cirrus 1 and has pectinate setae without basal guards on cirrus 2. Records of C. challengeri south of Japan are probably erroneous. However, there is an undescribed species of the ‘challengeri’ subgroup in the Indian Ocean, Indo-Malaya, Vietnam and southern China and yet more may occur in the western Pacific. The subgroups ‘malayensis’ and ‘challengeri’ require genetic investigation. Some comments are included on the arthropodal characters and geographical distributions of Chthamalus antennatus, C. dalli and C. stellatus