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Research Overview THE SHARK DIVE within Shark Reef Marine Reserve (SRMR) currently hosts the Bull Shark Tagging Programme. This research project is led by Juerg M. Brunnschweiler and funding is provided by: • Shark Foundation Switzerland The long term goal of the project is to establish SRMR as a prime site for shark research and to produce scientific data that will help towards the conservation of the shark species that regularly visit THE SHARK DIVE at Shark Reef. More specifically, the Bull Shark Tagging Programme aims to better understand bull shark behaviour and ecology. It uses the full spectrum of telemetry techniques, ranging from direct observation of sharks in their natural habitat to state-of-the-art satellite telemetry, as well as genetics and local ecological knowledge. Bull sharks can be encountered in great numbers at THE SHARK DIVE in the SRMR from January until September/October each year. This is when individual sharks can be directly observed and counted to, for example, estimate the population size. During the months of October/November into December, very few bull sharks are seen in the SRMR. Year after year they presumably move away from Shark Reef during these two months to either give birth or to mate. This is the most likely explanation because many females are seen with fresh mating scars when they return to the site in end of December and in January. Furthermore, pregnant females that left at the end of the year return non-pregnant the next year. A first and obvious question has been “where do the bull sharks go when they leave the SRMR?". A tool to address this question are pop-up satellite archival tags. As of September, 2009, a total of 14 bull sharks have been tagged with pop-up tags in Fiji. A preliminary analysis of the data collected so far tells us that the bull sharks move up and down the coast, but do not leave the Viti Levu coast on large-scale. We have learned a lot about at what depth and temperature they spend most of their time, but little about where exactly they go when they leave SRMR. As a consequence, we started to also tag the bull sharks with acoustic tags. These small tags are either attached externally or fed to the sharks. A tagged shark will be picked up by so-called listening stations (acoustic receivers) that are placed on Shark Reef and neighboring reefs. Such a receiver array provides us with presence-absence data of individual sharks, from which, together with the visual census data, inferences about site occupancy and small-scale movement patterns can be made. The following projects are currently underway in Fiji: • maintaining an exhaustive database about the shark dives. This is the backbone of our research into population dynamics, life cycles, inter- and intra-specific interactions and questions pertaining to the shark diving industry, namely the effects of Beqa Adventure Divers’ activities on the animals and the optimum procedures we ought to adopt in order to ensure a maximum of safety but also, of enjoyment for our clients • the Bull Shark Tagging Programme, to investigate the large- and small-scale movements of the bull sharks, for which we employ satellite and acoustic telemetry, but also use visual census data from the database. Whereas the large-scale movement studies are principally aimed at identifying and eventually protecting the bull shark nurseries in the rivers, the small-scale movement research is aimed at determining the optimum size and geographical extension of the protected area. Our most recent tagging sequence has the specific aim of testing several hypotheses linking the periodic disappearance of the bull sharks in September/October to their birthing and mating cycles • exploring local and traditional ecological knowledge along all of Fiji's major rivers. Local and traditional ecological knowledge have the potential to improve community-based coastal resource management by providing baseline data such as information about the presence, behaviour and ecology of species inhabiting these environments. Our major aim is to explore the potential of local and traditional ecological knowledge to identify shark river habitats in Fiji, to learn how locals regard and use sharks, and to capture ancestral legends and myths that shed light on the relationship between local people and these animals Shark Protection MAI TV Part One Shark Protection part two here • collecting tissue samples with the aim of contributing to the mapping of the bull sharks' global genetic structure and thus determine whether there are distinct local populations warranting distinct local conservation measures. The tissue samples are also used in toxicological studies linking the consumption of shark to dementia and mercury poisoning. We also collect discarded teeth which are being analyzed for exposure of the animals to fresh water • direct observation of the animals' behaviour. This research is principally aimed at deciphering dominance and aggression patterns and determining whether bull sharks are territorial (probably not) or even social (maybe). It also plays a critical role in helping us to better understand how to interact with the sharks we feed • regular fish counts aimed at recording any changes to the biodiversity within the SRMR and at improving our management of the area. Preliminary results indicate that as a consequence of changed feeding protocols, the fish population of Shark Reef has evolved from being predator- and scavenger-dominated to one in line with what would be expected of a vibrant and rich reef ecosystem. We have also recorded several range extensions, some of which spectacular and have identified a few fishes that may well turn out to be new species. The Shark Reef Fish List can be viewed online and is likely to develop into a proper Fiji fish list that will be set up as a wiki with scientific moderation from Hawaii • questionnaires investigating different aspects of ecotourism and the impressions and expectations of divers visiting the SRMR News and more information about the Bull Shark Tagging Programme can be found on the Save Our Seas Foundation Blog or at www.leucas.net. Literature The Shark Reef Marine Reserve: a marine tourism project in Fiji involving local communities. Journal of Sustainable Tourism (in press) A contribution to marine life conservation efforts in the South Pacific: The Shark Reef Marine Reserve, Fiji. Cybium 30 (Supplement): 133-139 Tracking free-ranging sharks with hand-fed intra-gastric acoustic transmitters. Marine and Freshwater Behaviour and Physiology 42: 201-209 First record of Carcharhinus leucas from Tonga, South Pacific. Marine Biodiversity Records 1: e51 A new and unexpected host for the sharksucker (Echeneis naucrates) with a brief review of the echeneid-host interactions. Marine Biodiversity Records 1: e41  |