ALBERT

Description: A two day workshop on Southern Ocean cephalopods was held in Hobart, Tasmania, Australia prior to the triennial 2006 Cephalopod International Advisory Council (CIAC) symposium. The workshop provided a second international forum to present the current state of research and new directions since the last Southern Ocean cephalopod meeting held in 1993. A major focus of the workshop was trophic ecology and the use of a variety of tools that can be applied in Southern Ocean trophic studies for both cephalopod and predator researchers. New tools that are being used as trophic indicators and tracers in food chain pathways include stable isotope, heavy metal and fatty acid signature analysis. Progress is also being made on understanding squid population dynamics in relation to other key components of the ecosystem by incorporating squid data in ecosystem models. Genetic barcoding is now of great value to fish taxonomy as well as other groups and it is expected that a cephalopod barcoding initiative will be an important tool for cephalopod taxonomy. There is a current initiative to produce a new cephalopod beak identification guide to assist predator biologists in identifying cephalopod prey items. There were also general discussions on specific taxonomic issues, Southern Ocean Cephalopod paralarvae and parasites, and suggestions for future CIAC workshop topics.

Description: The ocean margins contain a great variety of habitats and biological communities. Recent discoveries, such as deep-water coral reefs, show that these communities are poorly described and understood. However, observations have already indicated that benthic communities on ocean margins show high levels of spatial and temporal variation at all scales. The European continental margin is increasingly exploited for both biological resources (fisheries) and non-biological resources (oil, gas, minerals). Environmental management of the exploitation of continental margins requires an understanding of natural levels of variation inherent in biological communities that are potentially impacted by such activities. This paper presents a synthesis of the present knowledge of the spatial and temporal variation of slope communities. Priorities for future research and its technological development are discussed. The aim of this research is to provide a scientific basis for the environmental management of the continental slopes of Europe.

Description:  An ensemble of twenty four coupled ocean-atmosphere models has been compared with respect to their performance in the tropical Pacific. The coupled models span a large portion of the parameter space and differ in many respects. The intercomparison includes TOGA (Tropical Ocean Global Atmosphere)-type models consisting of high-resolution tropical ocean models and coarse-resolution global atmosphere models, coarse-resolution global coupled models, and a few global coupled models with high resolution in the equatorial region in their ocean components. The performance of the annual mean state, the seasonal cycle and the interannual variability are investigated. The primary quantity analysed is sea surface temperature (SST). Additionally, the evolution of interannual heat content variations in the tropical Pacific and the relationship between the interannual SST variations in the equatorial Pacific to fluctuations in the strength of the Indian summer monsoon are investigated. The results can be summarised as follows: almost all models (even those employing flux corrections) still have problems in simulating the SST climatology, although some improvements are found relative to earlier intercomparison studies. Only a few of the coupled models simulate the El Niño/Southern Oscillation (ENSO) in terms of gross equatorial SST anomalies realistically. In particular, many models overestimate the variability in the western equatorial Pacific and underestimate the SST variability in the east. The evolution of interannual heat content variations is similar to that observed in almost all models. Finally, the majority of the models show a strong connection between ENSO and the strength of the Indian summer monsoon.

Description: We describe the behaviour of 23 dynamical ocean-atmosphere models, in the context of comparison with observations in a common framework. Fields of tropical sea surface temperature (SST), surface wind stress and upper ocean vertically averaged temperature (VAT) are assessed with regard to annual mean, seasonal cycle, and interannual variability characteristics. Of the participating models, 21 are coupled GCMs, of which 13 use no form of flux adjustment in the tropics. The models vary widely in design, components and purpose: nevertheless several common features are apparent. In most models without flux adjustment, the annual mean equatorial SST in the central Pacific is too cool and the Atlantic zonal SST gradient has the wrong sign. Annual mean wind stress is often too weak in the central Pacific and in the Atlantic, but too strong in the west Pacific. Few models have an upper ocean VAT seasonal cycle like that observed in the equatorial Pacific. Interannual variability is commonly too weak in the models: in particular, wind stress variability is low in the equatorial Pacific. Most models have difficulty in reproducing the observed Pacific 'horseshoe' pattern of negative SST correlations with interannual Niño3 SST anomalies, or the observed Indian-Pacific lag correlations. The results for the fields examined indicate that several substantial model improvements are needed, particularly with regard to surface wind stress.

Description: Dietary composition of the onychoteuthid squid Moroteuthis ingens at the Falkland Islands was related to predator size, as shown by stomach contents and fatty-acid analyses. Comparisons were made between two size classes of squid: those of mantle length 〈200 mm and those of mantle length 〉200 mm. Smaller squid had frequently consumed crustaceans and cephalopods; fish were of secondary importance. Larger squid consumed mostly fish and moderate amounts of cephalopods, but had rarely consumed crustaceans. These findings were supported by comparisons drawn between digestive-gland fatty-acid profiles and the fatty-acid profiles of potential prey species. Fatty-acid analyses indicated that the crustaceans Euphausia lucens, Munida gregaria and Themisto gaudichaudii were important prey items of smaller squid, whereas stomach content and fatty-acid analyses indicated that Gymnoscopelus nicholsi of around 100 mm standard length represented much of the fish prey of larger squid.

Description: Ambae Island is the largest of Vanuatu’s active volcanoes. It is also one of the nation’s potentially most dangerous, with 60 million m3 of lake-water perched at over 1340 m in the summit caldera and over the active vent. In 1995, small phreatic explosions, earthquake swarms and heightened gas release led to calls for evacuation preparation and community volcanic hazard awareness programs for the ~9500 inhabitants. Differences in perspective or world-view between the island dwellers adhering to traditional beliefs (Kastom) and external scientists and emergency managers led to a climate of distrust following this crisis. In an attempt to address these issues, rebuild dialogue and respect between communities, outside scientists and administrators, and move forward in volcanic hazard education and planning for Ambae, we adapted and applied Participatory Rural Appraisal (PRA) approaches. Initial gender-segregated PRA exercises from two representative communities provided a mechanism for cataloguing local traditional viewpoints and hazard perceptions. Ultimately, by combining elements of these viewpoints and perceptions with science-based management structures, we derived volcanic hazard management guidelines, supported by an alert system and map that were more readily accepted by the test communities than the earlier “top-down” plans imposed by outside governmental and scientific agencies. The strength of PRA approaches is that they permit scientists to understand important local perspective issues, including visualisations of volcanic hazards, weaknesses in internal and external communication systems, and gender and hierarchy conflicts, all of which can hinder community emergency management. The approach we describe has much to offer both developing and industrialised communities that wish to improve their awareness programs and mitigative planning. This approach should also enhance communication and understanding between volcanologists and the communities they serve.

Description: Grab samples from the submarine Conical Seamount, located about 10 km south of the giant Ladolam gold deposit, Lihir Island, reveal the highest gold concentrations yet reported from the modern seafloor. Lavas from Conical Seamount are characterized by high K2O contents, high K2O/Na2O ratios, and high Ce/Yb ratios, which are typical of high-K igneous rocks from oceanic (island) arc-settings. The primitive character of the rocks from Conical Seamount implies a magmatic evolution related to a single eruptive phase, which contrasts with the more evolved rocks forming Lihir Island. Geochemical as well as mineral chemical data suggest that the melts from both Conical Seamount and Lihir Island originate from the same magma source. In common with the samples from Lihir Island, elevated oxygen fugacities of 0.7–2.5 log units above the FMQ buffer are recorded from the Conical Seamount lavas. There are distinct differences between the mineralization styles at Conical Seamount and at the Ladolam gold deposit, Lihir Island. While early-stage pyritic stockwork mineralization at Conical Seamount is hosted by clay-silica altered basaltic rocks with local alunite±kaolinite alteration, main-stage Au-mineralization occurs in sericite-alkali feldspar altered polymetallic sulfide-bearing siliceous veins. By contrast, early-stage pyritic stockwork mineralization at Ladolam is restricted to biotite–magnetite ± silica-altered monzodiorite, while the main-stage bulk-tonnage mineralization occurs as auriferous pyrite-bearing hydrothermal breccias which, in places, are cut by quartz–chalcedony–illite–adularia–pyrite±marcasite veins containing isolated bonanza gold grades.

Description: Cephalopods are highly sensitive to environmental conditions and changes at a range of spatial and temporal scales. Relationships documented between cephalopod stock dynamics and environmental conditions are of two main types: those concerning the geographic distribution of abundance, for which the mechanism is often unknown, and those relating to biological processes such as egg survival, growth, recruitment and migration, where mechanisms are sometimes known and in a very few cases demonstrated by experimental evidence. Cephalopods seem to respond to environmental variation both ‘actively’ (e.g. migrating to areas with more favoured environmental conditions for feeding or spawning) and ‘passively’ (growth and survival vary according to conditions experienced, passive migration with prevailing currents). Environmental effects on early life stages can affect life history characteristics (growth and maturation rates) as well as distribution and abundance. Both large-scale atmospheric and oceanic processes and local environmental variation appear to play important roles in species–environment interactions. While oceanographic conditions are of particular significance for mobile pelagic species such as the ommastrephid squids, the less widely ranging demersal and benthic species may be more dependent on other physical habitat characteristics (e.g. substrate and bathymetry). Coastal species may be impacted by variations in water quality and salinity (related to rainfall and river flow). Gaps in current knowledge and future research priorities are discussed. Key research goals include linking distribution and abundance to environmental effects on biological processes, and using such knowledge to provide environmental indicators and to underpin fishery management.