Continental-scale animal tracking reveals functional movement classes across marine taxa

Stephanie Brodie,Robert G Harcourt,Russell C Babcock,Elodie J I Lédée,Daniel C Gledhill,Colin A Simpfendorfer,Xavier Hoenner,Michelle R Heupel,Hamish A Campbell,Vinay Udyawer,Charlie Huveneers,Matthew D Taylor,Fabrice R A Jaine

doi:10.1038/s41598-018-21988-5

Abstract

Acoustic telemetry is a principle tool for observing aquatic animals, but coverage over large spatial scales remains a challenge. To resolve this, Australia has implemented the Integrated Marine Observing System’s Animal Tracking Facility which comprises a continental-scale hydrophone array and coordinated data repository. This national acoustic network connects localized projects, enabling simultaneous monitoring of multiple species over scales ranging from 100 s of meters to 1000 s of kilometers. There is a need to evaluate the utility of this national network in monitoring animal movement ecology, and to identify the spatial scales that the network effectively operates over. Cluster analyses assessed movements and residency of 2181 individuals from 92 species, and identified four functional movement classes apparent only through aggregating data across the entire national network. These functional movement classes described movement metrics of individuals rather than species, and highlighted the plasticity of movement patterns across and within populations and species. Network analyses assessed the utility and redundancy of each component of the national network, revealing multiple spatial scales of connectivity influenced by the geographic positioning of acoustic receivers. We demonstrate the significance of this nationally coordinated network of receivers to better reveal intra-specific differences in movement profiles and discuss implications for effective management.

Highlights

Animal telemetry has transformed our ability to remotely-monitor animals and provide critical insights into how they utilize their environment, such as revealing new and unexpected behavior relating to fine-scale habitat use, home range extent, inter-specific interactions, phenology, and migratory patterns[1]
There is a need to evaluate the effectiveness of this collaborative national network in monitoring animal movement ecology, and to identify the spatial scales that the network operates over
Our analyses demonstrated that removal of either Integrated Marine Observing System (IMOS) or non-IMOS installations produce a less well-connected system and reduce the ability of sub-networks to define functional movement classes (FMCs)

Summary

Introduction

Animal telemetry has transformed our ability to remotely-monitor animals and provide critical insights into how they utilize their environment, such as revealing new and unexpected behavior relating to fine-scale habitat use, home range extent, inter-specific interactions, phenology, and migratory patterns[1]. Australia is the only continent whose entire coastline is under the jurisdiction of a single nation This region provides a unique opportunity to examine the utility of a large-scale collaborative system for monitoring marine vertebrate movement ecology. The IMOS Animal Tracking Facility (IMOS ATF) facilitates large-scale, collaborative animal tracking research through the deployment of continental-scale curtains and grids of acoustic receivers[11] This strategically located[11], permanent array of acoustic receivers are integrated with a large number of independent, project-based, non-IMOS installations that are deployed by individual researchers and research teams to address regional research needs (Fig. 1a). There is a need to evaluate the effectiveness of this collaborative national network in monitoring animal movement ecology, and to identify the spatial scales that the network operates over Such an evaluation will demonstrate the utility of IMOS ATF to national user groups, and similar international acoustic telemetry platforms[13]. We assessed the utility of, and redundancy within, the IMOS ATF by: a) undertaking network analyses on acoustic receiver installations, and b) comparing whether FMCs can be discerned when only IMOS or non-IMOS installations are included

Methods

Results

Discussion

Conclusion