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Advances in the aquatic sciences
RESEARCH ARTICLE

Assessing variation in assemblages of large marine fauna off ocean beaches using drones

Brendan P. Kelaher A D , Andrew P. Colefax A C , Alejandro Tagliafico A , Melanie J. Bishop B , Anna Giles A and Paul A. Butcher A C
+ Author Affiliations
- Author Affiliations

A Marine Ecology Research Centre, Southern Cross University, National Marine Science Centre, PO Box 4321, Coffs Harbour, NSW 2450, Australia.

B Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia.

C NSW Department of Primary Industries, National Marine Science Centre, PO Box 4321, Coffs Harbour, NSW 2450, Australia.

D Corresponding author. Email: brendan.kelaher@scu.edu.au

Marine and Freshwater Research 71(1) 68-77 https://doi.org/10.1071/MF18375
Submitted: 5 October 2018  Accepted: 16 November 2018   Published: 22 January 2019

Abstract

The turbulent waters off ocean beaches provide habitat for large marine fauna, including dolphins, sharks, rays, turtles and game fish. Although, historically, these assemblages have proven difficult to quantify, we used a new drone-based approach to assess spatial and temporal variation in assemblages of large marine fauna off four exposed beaches in New South Wales, Australia. In total, 4388 individual large marine animals were identified from 216 drone flights. The most common taxa, bottlenose dolphins (Tursiops spp.) and Australian cownose rays (Rhinoptera neglecta), occurred in 25.5 and 19.9% of flights respectively. White (Carcharodon carcharias), bull (Carcharhinus leucas) and other whaler (Carcharhinus spp.) sharks were observed in <1% of flights. There was significant variation in the structure of assemblages of large fauna among beaches, with those adjacent to riverine estuaries having greater richness and abundance of wildlife. Overall, drone surveys were successful in documenting the spatio-temporal dynamics of an impressive suite of large marine fauna. We contend that emerging drone technology can make a valuable contribution to the ecological information required to ensure the long-term sustainability of sandy-beach ecosystems and associated marine wildlife.

Additional keywords: Carcharodon, dolphin, RPAS, ray, sandy-beach, shark, Tursiops, turtle, UAV, UAS.


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