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Hawksbill turtle (Eretmochelys imbricata) nesting populations and behaviors in the Republic of Vanuatu are poorly understood. In an effort to evaluate their internesting home range, post-nesting migration and foraging habitat home ranges, 7 post-nesting hawksbill turtles were satellite tagged at Moso Island, Republic of Vanuatu between January 2018 and January 2020. The mean internesting home ranges of two turtles was 0.8 km2 proximal to their nesting beach indicating possible value in establishing a marine protected area along the north coast of Moso Island during the nesting season. The Great Barrier Reef, Australia and New Caledonia were the two major post-nesting destinations. Hawksbill turtles are legally protected by law in both countries. Foraging home ranges for 4 hawksbill turtles in New Caledonia and Aneityum Island, Vanuatu ranged from 1.7 to 28.9 km2. It will be important to continue this study to better determine the total area of habitat utilization of the internesting hawksbills at Moso Island in order to facilitate the implementation of community-based conservation measures and to illuminate home range location and size.

Since the 1950's, 19 algal species were intentionally (e.g., aquaculture food) and/or accidentally (e.g., ballast water) introduced into Hawaii (Glenn and Doty 1990).

Breeding success of 5 Cory’s shearwater Calonectris diomedea sub-colonies of Lavezzu Island (Lavezzi Archipelago, Corsica) was checked annually for 25 consecutive years from 1979 to 2004. Between 1989 and 1994, 4 ship rat Rattus rattus controls were performed in several subcolonies. In November 2000, rats were eradicated from Lavezzu Island and its 16 peripheral islets (85 ha) using traps then toxic baits. We compare cost (number of person-hours required in the field) and benefit (Cory’s shearwater breeding success) of control and eradication. The average breeding success doubled when rats were controlled or eradicated (0.82) compared to the situation without rat management (0.45). Moreover, the average breeding success after eradication (0.86) was significantly (11%) higher than after rat controls (0.75). Furthermore, the great variation in breeding success recorded among sub-colonies both with and without rat control declined dramatically after eradication, suggesting that rats had a major impact on breeding success. The estimated effort needed to perform eradication and checking of the permanent bait-station system during the year following eradication was 1360 person-hours. In contrast, rat control was estimated to require 240 or 1440 person-hours per year when implemented by trained and untrained staff, respectively. Within 6 yr, eradication cost is lower than control cost performed by untrained staff and confers several ecological advantages on more ecosystem components than Cory’s shearwater alone. Improved eradication tools such as hand or aerial broadcasting of toxic baits instead of the fairly labour-intensive eradication strategy we used would dramatically increase the economic advantage of eradication vs. control. Therefore, when feasible, we recommend eradication rather than control of non-native rat populations. Nevertheless, control remains a useful management tool when eradication is not practicable.

The conservation status, ecology, and cultural importance of sea turtles at the three Polynesian atolls of Tokelau are presented. The green turtle, Chelonia mydas. is the most common species, occurring as a migrant breeder mostly during September through November. The hawks- bill, Eretmochelvs imbricata. is present in small numbers at all three atolls, but nesting is only known at Nukunonu Atoll. A third species, the loggerhead, Caretta caretta. has also been recorded on rare occasions. In Tokelau, sea turtles are considered "sacred fish" (ika ha) that must be shared among the entire village by an equitable system known as inati. The number of sea turtles has declined within historical times apparently as a result of modern and more efficient hunting methods.