Visualizing habitat use and behavior of whale sharks using the open tag, applications for ecotourism regulation.
- Published
- Accepted
- Subject Areas
- Animal Behavior, Conservation Biology, Marine Biology
- Keywords
- Data Visualization, Behavior
- Copyright
- © 2013 Levenson et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
- Cite this article
- 2013. Visualizing habitat use and behavior of whale sharks using the open tag, applications for ecotourism regulation. PeerJ PrePrints 1:e145v1 https://doi.org/10.7287/peerj.preprints.145v1
Abstract
Background. The rapidly decreasing cost of components and growing open source electronics industry has enabled access to improved tools for monitoring the behavior of aquatic species on a fine scale never before achieved. We use the new Open Tag as a novel approach to visualizing feeding behavior of whale sharks. Methods. The Open Tag is a Arduino compatible open-source inertial measurement unit for recording high speed motion sensor data to a microSD memory card. A three dimensional gyroscope, accelerometer, and magnetometer allow for calculating pitch, yaw, and heading, while depth and temperature sample continuously. The rechargeable lithium battery allows for deployments up to 7 days sampling at 100Hz. The Open Tag is placed in a hydrodynamic syntactic foam float, with a band that stretches around the dorsal fin. A galvanic release incorporated into the tag allows for a release time to be programmed and a VHF tag (ATS) aids in recovery. Results. An Open Tag was successfully deployed on a whale shark for 101 hours in August of 2013 in Yucatan Mexico. Behaviors noted included frequent surface intervals, even during the night when previously believed whale sharks were normally in deeper waters. A maximum depth of 49 meters was observed, with dives to 25 meters recorded regularly. We were able to identify possible harassment at the surface and defecation events. Conclusion. The Open Tag fills a unique niche in whale shark studies as a useful tool to better understanding of fine scale habitat use and behavior. By incorporating these data into Trackplot with data on the position of ecotour vessels, we can visualize behavior and investigate potential erratic changes in depth, heading and lateral movement amplitude indicative of harassment
Author Comment
Submitted for the 3rd International Whale Shark Conference.
Supplemental Information
Whale shark diurnal vertical movement
Diurnal changes in vertical movements recorded during the open-tag deployment. Day depicted in green & night in blue. Increased changes of swimming depth during daylight hours coincides with peak ecotour vessel activity.
