SEALNET: Facial recognition software for ecological studies of harbor seals

Abstract Methods for long‐term monitoring of coastal species such as harbor seals ( Phoca vitulina ) are often costly, time‐consuming, and highly invasive, underscoring the need for improved techniques for data collection and analysis. Here, we propose the use of automated facial recognition technol...

Full description

Bibliographic Details
Published in:Ecology and Evolution
Main Authors: Birenbaum, Zach, Do, Hieu, Horstmyer, Lauren, Orff, Hailey, Ingram, Krista, Ay, Ahmet
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2022
Subjects:
Online Access:http://dx.doi.org/10.1002/ece3.8851
https://onlinelibrary.wiley.com/doi/pdf/10.1002/ece3.8851
https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ece3.8851
Description
Summary:Abstract Methods for long‐term monitoring of coastal species such as harbor seals ( Phoca vitulina ) are often costly, time‐consuming, and highly invasive, underscoring the need for improved techniques for data collection and analysis. Here, we propose the use of automated facial recognition technology for identification of individual seals and demonstrate its utility in ecological and population studies. We created a software package, SealNet, that automates photo identification of seals, using a graphical user interface (GUI) software to detect, align, and chip seal faces from photographs and a deep convolutional neural network (CNN) suitable for small datasets (e.g., 100 seals with five photos per seal) to classify individual seals. We piloted the SealNet technology with a population of harbor seals located within Casco Bay on the coast of Maine, USA. Across two years of sampling, 2019 and 2020, at seven haul‐out sites in Middle Bay, we obtained a dataset optimized for the development and testing of SealNet. We processed 1752 images representing 408 individual seals and achieved 88% Rank‐1 and 96% Rank‐5 accuracy in closed set seal identification. In identifying individual seals, SealNet software outperformed a similar face recognition method, PrimNet, developed for primates but retrained on seals. The ease and wealth of image data that can be processed using SealNet software contributes a vital tool for ecological and behavioral studies of marine mammals in the developing field of conservation technology.