Habitat use of a Critically Endangered elasmobranch, the largetooth sawfish Pristis pristis, in an intermittently flowing riverine nursery

Endangered species research

James Keleher^1¹  Brendan C. Ebner^2,3²  Colin A. Simpfendorfer^4³  David L. Morgan^1⁴  Jeff M. Whitty^1⁵  Adrian C. Gleiss^1⁶ 

[1] Fish Health Unit, Centre for Fish &Fisheries Research, Murdoch University, Murdoch, Western Australia 6150, Australia^1;CSIRO Land and Water, Atherton, Queensland 4883, Australia^3;Centre for Sustainable Tropical Fisheries and Aquaculture, and College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland 4811, Australia^4;Freshwater Fish Group &TropWATER - Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, Townsville, Queensland 4811, Australia^2

关键词: Diel activity;    Acoustic telemetry;    Large woody debris;    Dry season;    Pristidae;   

DOI  :  10.3354/esr00837

学科分类：动物科学

来源: Inter-Research

【 摘 要 】

Knowledge of how an animal uses its habitat is a fundamental component of effective conservation strategies. The Critically Endangered largetooth sawfish Pristis pristis uses rivers and their estuaries as nursery habitats, where it is likely to be exposed to elevated pressures from anthropogenic-induced stresses including fishing (e.g. bycatch or direct harvest) and instream habitat modification and degradation (e.g. barriers, water extraction, and mining). With a paucity of data available on habitat use of P. pristis, we monitored the movements of 32 juveniles (952 to 2510 mm total length; mean ± SE = 1919 ± 64 mm) using acoustic telemetry to explore correlations between sawfish movement and abiotic as well as biotic variables over an 8 yr period (2008 to 2015) in the freshwater reaches of the Fitzroy River, Western Australia. Monitored juveniles were least active when they occupied deeper runs and pools in proximity to large woody debris by day and were most active during night-time and twilight hours when inhabiting shallow water such as glides, pool edges, and shallow runs. These shifts in activity and habitat use were primarily mediated by foraging and refuging behaviours, which were coupled to day-night cycling of light availability. Protection of these instream habitats and the understanding of their use by P. pristis are important for aiding in the management of intermittently flowing rivers that are used as nurseries for this species.

【 授权许可】

Unknown