Analysis of a new data set for sea surface temperature shows that the seawater temperature rise in 1998 in the southern Arabian Gulf was the largest since 1870; it also showed that there is an underlying rising trend of sea surface temperature across the whole of the measured area spanning 5 degrees longitude and 3 degrees latitude. Over the last 50 years, sea surface temperature rise was about 0.2 ± C per decade, though this has accelerated to about 0.45 ± C per decade in the last 20 years. The pattern in temperature values in each 1 degree 'cell' are used to show that, at any one time, temperature rises towards the east of this area, which supports the concept of a general anti-clockwise circulation in the southeastern half of the Arabian Gulf. Spatial and temporal patterns in sea surface temperature rises also show that the mean temperature eld at any location is similar to that which existed in the one degree cell immediately to its east approximately 30 years earlier.Coral cover in shallow water (<3 m depth) was <1 percent immediately following the 1998 event, due to near total mortality of vast areas of shallow Acropora (stagshorn) corals. Deeper than 3 m there was increasing survival of the large Porites ( boulder) corals, survival increasing with depth. Coral survival improved towards the east, though overall, less than twenty coral species were found altogether. Juvenile recruitment also increased towards the east, and at any one site, recruitment increased with increasing depth. The identity of new juveniles was mainly faviid corals, not the Acropora or Porites which dominated these reefs before the 1998 event. This suggests that there may be a phase shift to a different stable state in terms of coral communities. We also speculate that, because the Arabian Gulf contains an extreme warm-tolerant subset of the Indian Ocean coral fauna, the changes seen in the Gulf may re ect future patterns across a greater part of the Indian Ocean.

We investigated camps of black Pteropus alecto and red¯ying-fox P. scapulatus in the early dry season of 1992 (April±June) in Kakadu National Park, a World Heritage Area in the wet-dry tropics of north Australia. Fifteen camp-sites were located and two types of camps were de®ned: main camps containing > 1000 animals and a signi®cant component of young (P. alecto, n = 4; P. scapulatus, n = 2) and satellite camps of lesser size (P. alecto, n = 9; P. scapulatus, n = 3). The two species shared three camp-sites. All camps were in dense riparian vegetation (fresh and saltwater mangroves, paperbark forests, closed forest and bamboo), overhanging or adjacent to water inhabited by crocodiles, that would provide a protected microclimate and protection from predators. All camps were within 5 km or less of one or more unoccupied sites that were indistinguishable in landform or vegetation from camp-sites. In Kakadu NP riparian vegetation makes up about 6% of the park and is a non-limiting resource for¯ying-fox roosting. We propose that the initial colonization of camp-sites is essentially random when roost vegetation is nonlimiting and that factors such as predation by humans, cyclones and ®res determine the persistence and size of camps at the local level. At a broader temporal and spatial scale, interaction between the seasonal availability of forage and reproductive cycles is known to in¯uence the location, size and structure of Pteropus camps. We advance the hypothesis that colonies of¯ying-foxes could be moved to new campsites, a strategy that would facilitate resolution of the frequently problematic management of these animals.

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