BackgroundUnderstanding the distribution of marine biodiversity is a crucial first step towards the effective and sustainable management of marine ecosystems. Recent efforts to collate location records from marine surveys enable us to assemble a global picture of recorded marine biodiversity. They also effectively highlight gaps in our knowledge of particular marine regions. In particular, the deep pelagic ocean – the largest biome on Earth – is chronically under-represented in global databases of marine biodiversity.Methodology/Principal FindingsWe use data from the Ocean Biogeographic Information System to plot the position in the water column of ca 7 million records of marine species occurrences. Records from relatively shallow waters dominate this global picture of recorded marine biodiversity. In addition, standardising the number of records from regions of the ocean differing in depth reveals that regardless of ocean depth, most records come either from surface waters or the sea bed. Midwater biodiversity is drastically under-represented.Conclusions/SignificanceThe deep pelagic ocean is the largest habitat by volume on Earth, yet it remains biodiversity's big wet secret, as it is hugely under-represented in global databases of marine biological records. Given both its value in the provision of a range of ecosystem services, and its vulnerability to threats including overfishing and climate change, there is a pressing need to increase our knowledge of Earth's largest ecosystem.

1986. The constraints on cephalopods: why squid aren't fish. Can. J. Zool. 64: 1591-1605.The convergent evolution of cephalopods and fish has often been discussed on an anatomical basis, but recent advances in the knowledge of cephalopod life cycles, physiology, and biochemistry suggest that there are constraints on cephalopods that prevent them from competing directly ,with fish. These advances are reviewed against the background of detailed information on fish from the perspective that the basic inefficiency of the jet-propulsion system has required bioenergetic, physiological, and biochemical adaptations in squid which maximize their metabolic rates. Such "high-energy" adaptations are suggested to have resulted in the short life history and semelparous reproductive patterns that seem to characterize these coleoid cephalopods. Conversely, the physiology and biochemistry of fish give them distinct advantages for long lives and iteroparity. O'DOR, R. K., et D. M. WEBBER. 1986. The constraints on cephalopods: why squid aren't fish. Can. J . Zool. 64: 1591 -1605 L'kvolution convergente des ~Cphalopodes et des poissons a souvent fait l'objet de discussions basCes sur I'anatomie des organismes, mais, plus rkcemment, l'acquisition de connaissances sur les cycles biologiques des ckphalopodes, leur physiologie et leur biochimie indique que des contraintes empkhent les ckphalopodes de faire une compktition directe aux poissons. Ces nouvelles donnCes sont rCvisCes a la lumi&re des donnCes disponibles sur les poissons en tenant compte que 17inefficacitC inhkrente au systkme de dkplacements par propulsion a oblige les ~Cphalopodes a dCvelopper des adaptations bioCnergCtiques, physiologiques et biochimiques propres a maximiser leur taux de mktabolisme. De telles adaptations a coot knergktique ClevC ont probablement donnk lieu au cycle biologique court et au mode de reproduction semelpare qui semble car?.ctkriser ces ~Cphalopodes colkoi'des. Inversement, la physiologie et la biochimie des poissons donnent lieu a une vie longue et un mode de reproduction itkropare.[Traduit par la revue]

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The home-range size and location of reef-associated snapper Pagrus auratus: Sparidae were investigated by use of a radio acoustic-positioning telemetry (RAPT) system. Tags were surgically implanted in 5 snapper that were subsequently monitored every minute for a period of 5 mo, and then intermittently over another 7 mo. Site fidelity was high amongst these fish, with home ranges not exceeding 650 m in diameter or 139 600 m 2 in area. Eleven other snapper received tags by feeding and were tracked for periods of up to 2.5 d. Site fidelity was also high for these fish, with standardised estimates of home-range size not differing between the 2 groups. Home ranges overlapped considerably, indicating that the fish were not territorial. The location of the home ranges generally remained stable throughout the entire tracking period, although 1 fish relocated its home range bỹ 220 m. A new method of home-range estimation was developed, which matched the level of detail provided by the RAPT system, to directly estimate the time spent in an area. The relevance of this method and the residential behaviour of these fish are discussed, with reference to the general understanding of animal behaviour, previous investigations into snapper movement, and the selective capacity that may be imposed by marine reserves on fish behaviour.