Cafe Scientifique Tauranga - Sharks in the Bay
Event Information
About this Event
Welcome to Cafe Scientifique 2021! We are starting the year off with the very topical subject of sharks. This summer shark sightings in the Bay have been frequent. Come let Mel and Daisy, from University of Waikato Coastal Marine Science team, share their research and educate us on the shark populations in our local waters.
Remember:
- Please Register so we can cater for the right number of people
- $5 door fee covers the venue and light refreshments
- Doors open at 6:30pm for a 7pm start
Sharks are some of the most diverse apex predators within marine food webs and play a crucial role in the stability and sustainability of ecosystems. However, global populations are in decline due to a combination of anthropogenic pressures, in particular, the onset of commercial fisheries. The Bay of Plenty region hosts a diversity of habitats and species. However to date, research on sharks and their potential role in local food webs is largely restricted to analysis of offshore fisheries catch. The loss of top predatory sharks from marine ecosystems has already been reported in areas around the world. However, such changes can be difficult to identify and assess when information on shark populations is limited. We will present findings on pioneering research on bronze whaler sharks (Carcharhinus brachyurus) in New Zealand, and the biodiversity of benthic and pelagic shark species within Bay of Plenty waters.
Satellite telemetry presented novel findings on the seasonal movement patterns of bronze whaler sharks, challenging what was previously known about the distribution of this species. Furthermore, location transmissions allowed new metrics to be measured, such as swimming speed, while temperature preferences looked to be a driving factor in the seasonal shifts displayed by this species.
Baited Remote Underwater Video Systems (BRUVS) provide a standardised, non-destructive and fishery independent approach to estimating biodiversity indices and relative abundance measures for a variety of species. This technique was used in a pilot study to test its efficacy in surveying such population measures in temperate environments, such as the Bay of Plenty. In the process, a first look into much needed baseline information of community structure was provided. BRUVS were deployed at coastal sites near Matakana Island and Papamoa Beach, along with offshore sites around Motunau (Plate) Island. A total of six shark, two ray, and many fish species were observed on camera. We look forward to sharing this extraordinary footage with you!