Drone-Based High-Resolution Tracking of Aquatic Vertebrates
Abstract
:1. Introduction
2. Materials and Methods
2.1. Drone Piloting and Tracking
2.2. Measurement Accuracy
2.3. Data Preparation
2.4. Data Analysis
3. Results
4. Discussion
Considerations for Use of This Methodology
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Step | Process |
---|---|
1 | Check for appropriate weather conditions (low wind <10 kph = optimal, maximum of 30 kph). |
2 | Take off with drone and fully-charged battery, fly with camera pointed directly down. |
3 | Fly S-shaped search pattern above area of interest at 15–50 m altitude, depending on size of target species. Adjust height accordingly. |
4 | Once target species is spotted, immediately centre animal in the dead centre of viewing screen and descend to 2–5 m altitude. |
5 | Start recording video to record behaviours and aid in data processing, |
6 | Use gentle and consistent pilot inputs to remain directly above animal in this fashion. Avoid jagged and large inputs (this is true of any remote piloting, but especially in this case). |
7 | Continue tracking until animal is lost or battery gets to the 30% mark (this will prevent long-term battery degradation). |
8 | Return drone and land. |
Track Number | Species | Estimated Length (m) | Duration of Track (s) | Distance Travelled (m) | Mean Speed (m/s) | SD of Speed (m/s) | Sinuosity | Emax (103) | Pauses Greater than 5 s (/min) | Observed Foraging |
---|---|---|---|---|---|---|---|---|---|---|
EP1 | Epaulette | <0.7 | 406.3 | 116 | 0.29 | 0.21 | 0.92 | 4.36 | 1.03 | Yes |
EP2 | Epaulette | <0.7 | 377.7 | 160 | 0.42 | 0.25 | 0.81 | 6.34 | 0.48 | No |
EP3 | Epaulette | <0.7 | 429.5 | 172 | 0.40 | 0.26 | 0.87 | 5.99 | 0.56 | No |
EP4 | Epaulette | <0.7 | 350.6 | 169 | 0.48 | 0.23 | 0.80 | 7.56 | 0 | No |
EP5 | Epaulette | <0.7 | 602.8 | 222 | 0.37 | 0.23 | 0.95 | 4.85 | 0.40 | No |
EP6 | Epaulette | <0.7 | 468.9 | 179 | 0.38 | 0.36 | 0.97 | 4.50 | 0.90 | No |
EP7 | Epaulette | <0.7 | 316.6 | 69 | 0.22 | 0.19 | 1.46 | 2.12 | 2.08 | No |
EP8 | Epaulette | <0.7 | 301.8 | 117 | 0.39 | 0.28 | 1.04 | 4.29 | 0.40 | No |
EP9 | Epaulette | <0.7 | 185.7 | 89 | 0.48 | 0.27 | 0.86 | 5.99 | 0 | No |
BLK1 | Blacktip | >1.25 | 378.7 | 386 | 1.02 | 0.31 | 0.14 | 226.91 | 0 | No |
BLK2 | Blacktip | >1.25 | 680.6 | 454 | 0.67 | 0.26 | 0.19 | 116.03 | 0 | No |
BLK3 | Blacktip | >1.25 | 645.5 | 562 | 0.87 | 0.45 | 0.26 | 69.24 | 0 | Yes |
BLK4 | Blacktip | >1.25 | 300.2 | 161 | 0.54 | 0.17 | 0.40 | 29.13 | 0 | Yes |
LEM1 | Lemon | >1.25 | 357.4 | 286 | 0.80 | 0.23 | 0.20 | 107.39 | 0 | No |
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Raoult, V.; Tosetto, L.; Williamson, J.E. Drone-Based High-Resolution Tracking of Aquatic Vertebrates. Drones 2018, 2, 37. https://doi.org/10.3390/drones2040037
Raoult V, Tosetto L, Williamson JE. Drone-Based High-Resolution Tracking of Aquatic Vertebrates. Drones. 2018; 2(4):37. https://doi.org/10.3390/drones2040037
Chicago/Turabian StyleRaoult, Vincent, Louise Tosetto, and Jane E. Williamson. 2018. "Drone-Based High-Resolution Tracking of Aquatic Vertebrates" Drones 2, no. 4: 37. https://doi.org/10.3390/drones2040037