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Notes: Abstract The distribution and abundance of the late-stage phyllosoma larvae of Panulirus longipes cygnus George and the distribution and densities of the final larval stage, the puerulus, both in the plankton and at settlement along the coast, were investigated. A total of 3,617 late-stage phyllosoma (Stages VI to IX) and 301 puerulus larvae were caught at 187 plankton stations during the July to November periods 1974, 1975 and 1976 off the west coast of Australia between 29°00′ to 32°30′S and 113°30′ to 115°00′E. The depth range sampled was 0 to 35 m on the continental shelf and 0 to 90 m off the shelf. During onshore/offshore cruises with similar sampling effort on and off the shelf, 1,169 late-stage phyllosoma larvae were taken, of which only 9 were caught on the shelf, and these near the outer edge. A series of cruises sampling two areas beyond the shelf near 29°30′ and 32°00′S yielded 2448 late-stage phyllosoma, with greater densities of larvae in the northern location. The settlement of puerulus-stage larvae along the coast in the same geographical range was also greater in the north than in the south. The data from the onshore/offshore cruises showed a definite effect of moon phase on numbers of puerulus larvae caught on the shelf, with higher catches near new moon. The low numbers of puerulus larvae (usually 0, 1 or 2 individuals) caught at all stations showed that the puerulus stage is sparsely distributed in the plankton. Fewer puerulus larvae were present at the surface than at lower depths, but it was not possible to determine a depth preference for the puerulus between 10 m and the lowest depths sampled because of the low catch numbers. No relationships were found between puerulus larvae density and surface-water temperature, salinity, or plankton biomass at each station. Data on the larval distributions indicate that, near the end of their planktonic existence, the majority of the late-stage phyllosoma larvae of P. longipes cygnus are not carried onto the shelf, where mixing of oceanic and continental shelf waters occurs only on the outer third, but are transported southward by oceanic circulation beyond the shelf. The puerulus moults from the last phyllosoma stage beyond the shelf and completes the larval cycle by swimming across the shelf and settling in the shallow reef areas.

Notes: Abstract Studies off the west coast of Australia showed that the phyllosoma larvae of Panulirus cygnus George undergo a diurnal vertical migration, with light as an important factor influencing the depth distribution of all 9 phyllosoma stages. The early stages (I to III) occurred at the surface at night regardless of moonlight intensity, whereas late stages (VI to IX) concentrated at the surface only on nights with less than 5% of full moonlight. Midday peak densities of early-stage larvae occurred in the 30 to 60 m depth range while those of mid (IV to VI) and late stages were in the 50 to 120 m range. Depths of peak densities of larvae increased with distance offshore. The limits of vertical distribution of the phyllosoma remained within ranges of illuminance which were estimated to be in the order of 50 to 250 μE m-2 sec-1 for early stages, 20 to 200 μE m-2 sec-1 for mid stages and 5 to 50 μE m-2 sec-1 for late stages. Minimal rates of net vertical movement were estimated for the larvae. Early stages exhibited mean net rates of ascent and descent of 13.7 and 13.0 m h-1, respectively, while the rates for mid stages were 16.0 and 16.6 m h-1 and for late stages 19.4 and 20.1 m h-1. Diurnal migrations and vertical distribution are shown to have a vital role in the relationships between circulation in the south-eastern Indian Ocean and the transport and dispersal of the phyllosoma larvae. The diurnal migrations of early stages place them at the surface at night, when offshore vectors of wind-driven ocean-surface transport dominate, and below the depth of wind-induced transport during the day, when offshore vectors are small or negative, thus accounting for their offshore displacement. Mid and late stages, because of their deeper daytime distribution and absence from the surface on moonlight nights, are predominantly subject to circulation features underlying the immediate surface layer. This is hypothesized to account for the return of the phyllosoma to areas near the continental shelf edge by subjecting them to a coastward mass transport of water which underlies the immediate surface layer.

Notes: Abstract Juvenile Kyphosus cornelli were sampled and observed at Disappearing Island reef flat, Abrolhos Islands, in 1981 and 1984, and their diet, intestinal morphology and gut microflora examined. K. cornellii is partially carnivorous during its early post-settlement stages. Animal material forms a smaller proportion of its diet at this time than is the case for most other reef fishes that are herbivorous as adults. Anatomical specializations of the gut are present when the K. cornelli juveniles settle onto to the reef, and a gut-resident microflora develops by the time they grow to 36 mm fork length. The development of fermentative microbial digestion at an early stage appears to reduce K. cornelii's dependence on animal material in the diet. Relative gut length increases rapidly during the transition to a strictly herbivorous diet.

Notes: Abstract On an 85 km stretch of coastline along the western and northwestern edge of North West Cape Peninsula, Western Australia, are numerous beaches used for nesting by the green turtle Chelonia mydas. Many other beaches in the area are not so used. Nesting beaches displayed three characteristics that distinguished them from non-nesting beaches: the salinity of the sand moisture at nesting depth was lower, the salt content of surface sand was lower, and the beaches were sheltered from prevailing winds. Several beaches on which turtles did not nest exhibited these characteristics, but possessed sand platforms of reduced elevation above sea level. These observations are discussed in relation to the question of what cues green turtles use in selecting nesting beaches.

Notes: Two herbivorous fishes of the genus Kyphosus (family Kyphosidae) possess unique digestive tracts among fishes, with well-developed caecal pouches and a complex gut-resident microflora. The presence of high concentrations of volatile fatty acids in the gut confirms fermentative digestion in fishes for the first time.