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The attraction or provisioning of sharks for the purpose of tourism is a lucrative and popular industry that remains controversial regarding its possible risks to target species and impacts on local ecosystems. The long-term impacts of such activities on the behaviour and movement patterns of sharks have typically been difficult to establish as most studies investigate contemporary behaviour concurrent with existing operations and thus have no comparative base from which to compare effects. We compared patterns of residency and behaviour of acoustic-tagged white sharks at the Neptune Islands in South Australia between periods before and after an abrupt and sustained doubling of cage-diving effort that occurred in 2007. The number of sharks reported by cage-dive operators significantly increased after 2007. Comparisons also revealed there were significant increases in sharks' periods of residency, the periods spent within areas where shark cage-diving operations occur and changes in sharks' diel pattern of habitat use. Changes were site-specific with no significant differences in shark behaviour revealed over the same period at an island group 12 km from regular shark cage-dive sites. The results suggest that cage-diving operations can lead to long-term changes in the site-specific behaviour of a highly vagile shark species which may need to be considered in the context of their conservation and in managing the impacts of the industry. [ABSTRACT FROM AUTHOR]

nimal movement is a pivotal element of many ecological processes, and on ocean-exposed sandy shores, ghost crabs (genus Ocypode) undertake extensive nocturnal forays on the beach surface. Because crab populations are also threatened by vehicle traffic, indicators that can detect sublethal effects before population declines are manifest are important. To this end, we tested on a barrier island in Eastern Australia whether movement patterns of crabs respond predictably to disturbance by vehicles; this was done by tracking (using the spool-and-line technique) crabs at night in beach sections open and closed to traffic. Beach traffic not only halved population densities of crabs on the unvegetated beach seawards of the dunes, but it also fundamentally changed crab behaviour and movement: individuals from beach areas rutted by tyre tracks travelled shorter distances in a more erratic zigzag pattern, and they had significantly compressed home ranges. Such behavioural changes linked to human pressures could be well suited as an early warning signal for wider negative ecological impacts (as demonstrated by reduced abundances). They also emphasize the need to incorporate sublethal effects into the assessment and management of ecological changes resulting from beach recreation. [ABSTRACT FROM AUTHOR]

Sea anemones that host obligate symbiotic anemonefish are ecologically important throughout many coral reef regions of the Indo-Pacific. This study provides the first quantitative data on larval settlement rates and juvenile development of two species of host sea anemone, Heteractis crispa and Entacmaea quadricolor. Larvae were reared from broadcast spawned gametes of sexually reproductive male and female anemones collected from the Solitary Islands Marine Park, NSW, Australia. Prior to the start of the experiments, H. crispa larvae were reared for 3 days after spawning in March 2004 and E. quadricolor larvae were reared for 4 days after spawning in February 2005. Larval settlement onto biologically conditioned terracotta tiles in outdoor flow-through seawater aquaria was first recorded 4 days after spawning for H. crispa and 5 days after spawning for E. quadricolor. Peak settlement occurred 10 days after spawning, with a mean of 33.4 and 50.3% of the original groups of 350 larvae in replicate tanks settling for H. crispa and E. quadricolor, respectively. Tentacles arose as outpocketings of the oral region, at first appearing as small rounded buds. These buds elongated to form long, thin, tapering tentacles in H. crispa, whereas E. quadricolor tentacles had slight bulbs below the tips. Juvenile anemones, especially H. crispa, were found to have very different colouration and markings when compared with adult anemones, and therefore the descriptions and images provided here will enable correct identification of juvenile recruits. [ABSTRACT FROM AUTHOR]

Little Penguins, Eudyptula minor, breed in several small colonies in New Zealand and Australia. In this study, we compare the birds’ diving performances at different sites situated throughout their breeding range. Environmental conditions and breeding success vary drastically amongst colonies, but all birds feed on similar types of prey and face similar limitations on their foraging range. We examined several diving parameters and calculated the proportion of foraging zone available during breeding to examine whether oceanographic and geographic factors in the foraging zone can explain variations in diving behaviour and fledging success among the different colonies. In colonies with high fledging success, Penguin Island and Oamaru, penguins made shallow dives <50 m depth and had lower diving effort. More than 90% of the foraging zone was in waters <50 m depth in these colonies. Motuara Island also has shallow waters with 95% <50 m depth, but the fledging success was low. Phillip Island has only 42% of waters <50 m and comparatively low fledging success. Thus, penguins dived deeper and showed a higher diving effort in colonies with lower fledging success (Motuara Island and Phillip Island), indicating that they were disadvantaged compared to conspecifics from other colonies that dived shallower and with a lesser diving effort. We concluded that bathymetry is an important factor, but not the only one, which influences fledging success. [ABSTRACT FROM AUTHOR]

Focuses on a study of the short-term movements and behavior of the whale sharks at Ningaloo Reef in Western Australia. Information on whale sharks; Materials and methods; Results of the study.