This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility:


peer-reviewed publication


AI-enabled bio-loggers capture rare bird behavior

AI naturalists record rare bird behavior
Example use of our bio-loggers for rare event detection and recording. A) A bio-logger was used in this study. B) Bio-logger attached to the back of a streaked shearwater. C) The bird with the bio-logger is released and freely moves in a wild environment. The bio-logger automatically records videos of interesting events without supervision by researchers. D) Example frames and sensor data collected by our bio-logger showing foraging behaviors of streaked shearwaters. Credit: PNAS Nexus (2024). DOI: 10.1093/pnasnexus/pgad447

For centuries, naturalists have braved trackless forests, windy clifftops, and the cramped confines of blinds and submarines, hoping to capture rare behaviors that might reveal important aspects of animal biology and ecology. Takuya Maekawa and colleagues sought to deploy wearable trackers, which have become common in animal biology, to capture rare behaviors for study.

As animal-borne video loggers can only capture a few hours of video due to battery limitations, a key challenge is deciding when to record. The authors created an on-device AI program capable of "unsupervised learning" to automatically find and record rare behaviors without supervision by human naturalists.

The findings are published in the journal PNAS Nexus.

First, an outlier detector program was trained on unlabeled accelerometer and water-depth data from seabirds to automatically determine when an unusual behavior is taking place. This outlier program was used to create streamlined outlier detectors—one for accelerometer data and one for water-depth data—that fit on a low-energy micro control unit on a logger with limited memory and .

Rare behaviors recorded by AI-enabled bio-loggers affixed to streaked shearwaters. Credit: Tanigaki et al, Osaka University

These detectors turn on a of the logger when a rare behavior occurs in real time. The final AI-enabled bio-logger includes a video camera, three-axis acceleration sensor, GPS unit, water pressure sensor, thermometer, magnetometer, and illuminometer, which was then affixed to a streaked shearwater (Calonectris leucomelas).

The bio-logger weighs 23 g, less than 5% the weight of a shearwater. In in 2022, the authors attached the bio-loggers to 18 birds.

The acceleration-based rare-behavior detectors recorded videos of vigorous head shaking near the beginning of flight that the authors hypothesize may function to remove nasal salt gland fluids and other external materials to increase subsequent flight efficiency. The depth-based rare behavior detectors captured 50 minutes of active foraging for fish—including preliminary below-water peeks before diving— rarely caught on camera.

According to the authors, AI-enabled bio-loggers can be used on a range of species to capture many kinds of seldom-seen moments, including deep-sea mating rituals, the hunting strategies used for rare prey items, and the causes of death of wild animals.

More information: Kei Tanigaki et al, Automatic recording of rare behaviors of wild animals using video bio-loggers with on-board light-weight outlier detector, PNAS Nexus (2024). DOI: 10.1093/pnasnexus/pgad447

Journal information: PNAS Nexus

Provided by PNAS Nexus

Citation: AI-enabled bio-loggers capture rare bird behavior (2024, January 17) retrieved 12 April 2024 from
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Explore further

Birdwatching from afar: AI-enabled camera system to target specific behaviors


Feedback to editors