Bats provide important ecosystem services throughout the South Pacific but many species are threatened. The Fiji archipelago has a rich bat fauna yet few arrangements exist to promote the conservation of this group. From July 2008 to March 2011 we visited important sites identified in previous surveys for bats on Vanua Levu, Taveuni, Viti Levu and the Yasawa Islands. We netted and recorded five of Fiji's six bat species (Pteropus tonganus, Pteropus samoensis nawaiensis, Notopteris macdonaldi, Chaerephon bregullae and the Critically Endangered Mirimiri acrodonta). This was only the sixth recorded capture of M. acrodonta. P. tonganus is widespread in Fiji and exploits many different environments. P. samoensis nawaiensis mostly uses forested areas, and large tracts of forest are required for its long-term protection. Cave protection is vital for the two insectivorous species (C. bregullae and Emballonura semicaudata) and N. macdonaldi. In particular, the Nakanacagi maternity site remains globally significant for C. bregullae. E. semicaudata was not caught or detected during our surveys. It appears to be extinct from most large islands in Fiji and has abandoned the only large cave roost (Yaqeta) observed 10 years ago. This species has disappeared from or declined dramatically on Vanuatu, Samoa, Tonga and Fiji. We recommend that the category of E. semicaudata semicaudata on the IUCN Red List be changed to Critically Endangered. Management priorities should focus on community engagement and education, and improved cave and forest management and protection.

Cave temperature monitoring was carried out in the Cueva del Agua de Iznalloz, Granada, Spain, a cave that has great tourist potential and which has been maintained under natural conditions for over 30 years. The cave temperature under natural conditions was used to identify possible anthropogenic influences, in order to distinguish these from the variations directly related to natural changes. In particular, the relative influence of external weather conditions, thermal modification caused by visitors and the subsequent thermal recovery of the cave were identified. In addition, controlled experiments investigated the effect of two large-scale visits (980 and 2088 visitors day−1) to the cave interior, before any tourist activities in the cave were undertaken. Correlation and spectral analyses of time series were used to determine the thermal behaviour of the cave over time. The effect of both mass visits on the air temperature in the interior of the cave was very rapid (2.5 min). The maximum perturbation of air temperature within the cave during the two experiments was after 30 and 70 min. The memory effect for temperature whilst the cave was open to the public was estimated to be 5–6 h, whilst the response to external meteorological changes exceeded one week. A permanent visitor capacity of 53 people ensures that the natural cave temperature can be regained within 4–5 h. The cave can only support small groups of visitors, not the massive visits characteristic of show caves.