CALIBRATING UAS PHOTOGRAMMETRY TO DERIVE DELPHINID POPULATION DEMOGRAPHIC PARAMETERS
This project aims to develop a method to rapidly assess delphinid population age structure. This will ultimately provide an assessment of population growth and survival rates, and early insight into whether there may be cause for concern for specific populations.
The power to detect population increases or declines using traditional photo-identification methods typically requires decades of data collection before changes in vital rates (e.g. survival, fertility etc.) manifest themselves as changes in population size. The age structure of a population represents an informative parameter to evaluate the health and sustainability a population. New technologies are available that enable assessment of group composition and population age structure, as well as measures of individual animal health that can ultimately provide assessment of population growth and survival rates, and early insight into whether there may be cause for concern for these populations. This project consists of a four-phase study to assess the feasibility of using small Unoccupied Aerial Systems (UASs, or drones) to determine the population age structure of mid-sized delphinids. For this project, we will focus on the Hawaiian population of spinner dolphins, off the Kona coastline (Hawaii).
The long-term objective of this project is to define the age structure of the spinner dolphin population off the Kona coastline (Hawaii). Understanding the age structure of this population will provide a means by which to assess its trajectory and health status. This project will be achieved via four phases (see figure 1 below) using UAS photogrammetry (i.e., science of measuring objects through photographs). More information on each phase can be found on the links associated.
Figure 1. Schematic overview of the study components to assess the feasibility of using multi- rotor Unoccupied Aerial System (UAS) -photogrammetry to determine free-ranging delphinid group age composition and population age-structure.
The aims of the first two phases of this project are to (Figure 1, phase 1 and 2; click here for more information):
Collect hands-on physical measurements and UAS aerial images of dolphins at a public facility (Dolphin Quest Oahu, Hawaii).
Calibrate and test the precision of UAS-obtained length measurements of dolphins at a public facility by comparing UAS-derived length estimates with hands-on measurements of the dolphins.
Test the sensitivity of UAS-photogrammetry in converting length estimates (meters) to age-class of an individual.
The aims of the last two phases of this project are to (Figure 1, phase 3 and 4; click here for more information):
Collect aerial images of the Kona (Hawaii) population of spinner dolphins.
Estimate the length of the spinner dolphins.
Develop age-length growth curves for Hawaiian spinner dolphins.
Assess the age structure of the Kona population of spinner dolphins.
Lars Bejder - MMRP
Fabien Vivier - MMRP
Cormac Booth - SMRU Consulting
Erin Oleson - NOAA/PIFSC
Amanda Bradford - NOAA/PIFSC
Marie Hill - NOAA/JIMAR
Kristi West - Stranding network/MMRP
Jason Baker - NOAA
Aude Pacini - MMRP
Julie Rocho-Levine - DQ
Randall Wells - Sarasota Dolphin Research Program