International Collaborative Expedition to study Sub-Antarctic Indigenous Fish
Short Title: ICEFISH
Project URL: http://www.icefish.neu.edu/
Proposal URL: http://classic.ipy.org/development/eoi/proposal-details.php?id=93
In a world experiencing climate global changes, loss of biodiversity and depletion of fisheries, the biotas of the Antarctic and the Sub-Antarctic offer compelling natural laboratories for understanding the evolutionary impact of these processes. Since the IGY (1957-58), biologists have made impressive progress in understanding the Antarctic ichthyofauna. However, research integration into the broader marine context has been limited, largely due to lack of access to Sub-Antarctic fishes. These fishes, in particular those of the dominant suborder Notothenioidei, are critical for a complete understanding of the evolution, population dynamics, eco-physiology and eco-biochemistry of their Antarctic relatives.
The ICEFISH programme is designed to fill these critical gaps in our knowledge. Cruises, encompassing the South Atlantic, South Pacific and South Indian Ocean sectors constitute the ICEFISH programme, the first comprehensive international survey of the Sub-Antarctic marine habitat. The first, ICEFISH-2004 (17 May -17 July 2004) was a resounding success. Extensive fishing was performed in the South Atlantic sector: Burwood Banks, Falkland Islands/Islas Malvinas, Shag Rock, South Georgia, South Sandwich Islands, Bouvetoya, and Tristan de Cunha, at depths ranging from tidepools to the abyss (for information on the cruise, participants, and detailed science projects, see www.icefish.neu.edu).
Although autonomous, ICEFISH-2007 builds on the important legacy of ICEFISH-2004. It will sample the Sub-Antarctic Pacific sector, including Campbell and Scott Islands, Antipodes, Auckland, Macquarie, and Balleny Islands. Fishing will be multi-modal, using Otter, mid-water, Blake and MOCNESS trawls, plankton nets, beach seining, tide pooling, and traps. We will charter a suitable ice-strengthened ship/icebreaker, equipped with aquaria with running seawater to maintain live specimens, and with high-quality research laboratories. Twenty-four to 28 scientists will participate, largely those of the 2004 cruise, ensuring continuity of the scientific focus of the ICEFISH programme. The scientific activity will cover a wide range of topics, many of which will develop work carried out in ICEFISH-2004. We will summarise some of these topics:
- Systematics and evolutionary studies to relate Sub-Antarctic notothenioids to their Antarctic relatives through morphological, molecular and cytological analyses. The diversity of habitats and attendant species likely to be collected in ICEFISH 2007 clearly warrant such a comparative analysis, which will shed light on evolutionary diversity and radiative capacity within this sub-order.
- Life history strategies and population dynamics to characterise the composition, distribution, habitat preferences and diets of the Sub-Antarctic species, and larval recruitment.
- Diversity and biogeography. Documentation of fish biodiversity and possible discovery and description of unknown species, for example in the vicinity of the Balleny Islands and Scott Island (CCAMLR Statistical Subarea 88.1), where the fish fauna is poorly known. As transition zones between the Antarctic and Sub-Antarctic notothenioid faunas, these islands are key to recognizing and understanding latitudinal gradients in faunal composition in the Pacific Sector of the Southern Ocean. Liparids of the Southern Hemisphere are important from an evolutionary and zoogeographic perspective; many of these species are known only from one or two specimens. In addition, new species are still being found frequently. ICEFISH-2007 would be an important opportunity to sample previously poorly sampled regions to add to knowledge of the distribution and evolution of the family. Collection at depths below 1000 m is desirable.
- Physiological, biochemical and molecular-biological studies of organ and tissue systems to analyse the evolutionary basis of the adaptations of high-Antarctic nototothenioids relative to their ancestral stock.
- Genomic resources for Sub-Antarctic notothenioids (nucleic-acid libraries for comparative studies of the genomes of high- and low-latitude species). Because of the causal linkage between the thermal histories of marine environment, and the waxing and waning of the antifreeze trait, the extent of the antifreeze genotypic and functional capacity in related notothenioids within and outside of the high-Antarctic is an excellent biological indicator of regional variations or changes in thermal environments in the Southern Ocean. Spleen and testis tissues will be frozen for future preparation of DNA and RNA that will be used to evaluate the antifreeze glycoprotein genotype, Erythrocytes from red-blooded species and white blood cells from icefishes will be embedded in agarose plugs and used to prepare high molecular weight DNA for the construction of bacterial artificial chromosome (BAC) libraries. The BAC libraries will permit the global analysis of genome evolution of the notothenioids driven by thermal challenges.