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Situated about 500 km off the Malagasy east coast, the island of Tromelin is a key nesting site for the endangered green turtle, Chelonia mydas, in the south Western Indian Ocean. Nesting turtles found in this isolated island have been closely monitored since the 1970s, but the most recent estimates of nesting parameters date from 1986. Using mark-recapture data, track counts, and nests monitoring data collected over the 2009/2010 nesting peak, reproductive characteristics, population size, and offspring production were updated and discussed in the light of the track survey undertaken from 1986 to 2010. Females showed a consistent reproductive behaviour compared with previous studies in terms of clutch frequency (2.75 +/- 1.46) and nesting success (0.65). Nest indices such as hatching success (0.76 +/- 0.25) and emergence success (0.61 +/- 0.33) were also included in the range of values calculated in the 1980s. Importantly, the estimated number of nesters and production in eggs and hatchlings were similar to older estimates, suggesting a relative demographic stability. For the 2009/2010 year-long nesting season, the size of the nesting population was estimated at about 1500 individuals, which produced around 480,900 eggs (+/- 103,900), resulting in 289,200 emerging hatchlings (+/- 152,000). These results are promising and support the effectiveness of conservation measures undertaken in the Iles Eparses, but further comparable monitoring is needed in the coming years to confirm the stability in Tromelin's green turtle nesting population.

This paper describes predation tactics used by the saltwater crocodile (Crocodylus porosus) on flatback (Natator depressus) and olive ridley (Lepidochelys olivacea) sea turtles on nesting beaches in northern Australia. For adult turtles, crocodiles used both a sit-and-wait tactic in which they attacked a turtle at the water's edge after it completed nesting and an active hunting strategy in which crocodiles followed turtle tracks into the dunes to attack turtles at nest sites. Saltwater crocodiles also hunted sea turtle hatchlings in the dunes and excavated a sea turtle nest and consumed the eggs. The protection of saltwater crocodiles in Australia starting in the early 1970s has led to increased population sizes and a greater proportion of larger individuals. This likely has resulted in increased predation rates on sea turtles over several decades, which should be considered as an important mortality component for some tropical nesting aggregations.

Field Island in Kakadu National Park, Northern Territory, Australia, supports a nesting population of flatback turtles (Natator depressus) monitored since 1990. We summarize 9 years of survey data for this location and make recommendations for future research. At least 221 nesting flatbacks were tagged at Field Island between 1990 and 2001. Nightly emergence rates indicate that Field Island is a locally and regionally important rookery for flatbacks with no other species recorded nesting. The mean interseasonal remigration period was 2.82 years. Female flatbacks laid clutches of similar sizes to those reported for other Australian rookeries, but nests tended to be deeper than those on nearby mainland beaches. No evidence of size decline (curved carapace length) occurred over the years, and mean curved carapace length was similar to those observed at other nesting rookeries. The amount of biological information now available for the Field Island rookery and the number of nesting turtles already tagged makes it valuable as an index site for flatback turtles in northern Australia.