In the hidden depths of coastal ecosystems, the dynamic interplay between hard-shelled marine mollusks and their predators unfolds silently yet profoundly influences the health of these environments. Organisms like clams and snails, essential for stabilizing shorelines, filtering water, and supporting biodiversity, face mounting threats from ocean acidification and burgeoning populations of mobile shell-crushing predators. Despite their importance, deciphering the rapid and often submerged interactions that govern these predator-prey relationships has long posed a formidable scientific challenge.

The primary obstacle in studying these underwater predation events lies not only in their elusive locations but also in the fleeting nature of the encounters. Predators such as the whitespotted eagle rays (Aetobatus narinari) forage silently in subtidal zones where direct visual observation is hindered by light availability and water clarity. Consequently, the critical ecological process of mollusk consumption remains difficult to quantify in natural settings, leaving a significant knowledge gap in coastal marine ecology.

Unexpectedly, these predation events broadcast distinct acoustic signatures through the water. The fracturing and crushing of clam and snail shells generate unique sounds—transient acoustic signals rich with ecological information. Employing passive acoustic monitoring techniques coupled with autonomous recording devices, researchers can now “listen in” on these feeding behaviors as they happen in situ, capturing data inaccessible through visual surveys alone. Nonetheless, the challenge remains to reliably isolate these faint shell-crunching sounds amid the cacophony of underwater noise.

Addressing this, a team from Florida Atlantic University (FAU) has created an innovative machine learning framework designed to enhance the detection and classification of these subtle shell-crushing acoustic events. Through controlled aquarium trials featuring whitespotted eagle rays—a species renowned for their shell-cracking feeding strategy—the researchers built and trained an AI system adept at distinguishing feeding sounds from ambient oceanic noise, vastly advancing the capability to monitor predator-prey interactions acoustically.

This framework employs a sophisticated, multi-tiered approach. Initially, it processes extensive underwater audio recordings to identify potential predation events via acoustic pattern recognition. Subsequent analytical layers refine these detections by using machine learning classifiers to minimize false positives, thereby filtering actual shell-crushing events from environmental background sounds with high precision.

Beyond mere detection, the system also categorizes the type of mollusk prey consumed during these events. This is achieved by integrating traditional classification algorithms such as random forests with advanced deep learning architectures, including long short-term memory networks (LSTMs) and convolutional neural networks (CNNs). Each method is fine-tuned to recognize nuanced features in the acoustic structure of shell-crushing sounds, enabling detailed insights into prey identity.

Significantly, the study, recently published in the journal Ecological Informatics, demonstrates that complex AI architectures are not always essential for robust performance. Simplified models leveraging gammatone feature cepstral coefficients (GTCCs)—a biologically inspired auditory filterbank approach—proved nearly as effective as deep learning models in detecting shell-crushing sounds, while demanding significantly less computational power. This finding holds promise for scalable, long-duration deployment in challenging marine environments where energy and processing capacity are constrained.

As Laurent Chérubin, Ph.D., a research professor at FAU’s Harbor Branch Oceanographic Institute and lead author, emphasizes, these acoustic signals reveal substantial ecological information beyond mere occurrence. Passive acoustic monitoring represents a transformative tool, offering unprecedented access to predator-prey dynamics in otherwise inaccessible ocean habitats, enhancing our understanding of marine ecosystem functionality.

The implications for coastal ecosystem management are profound. By remotely detecting and classifying predation events, the new technology enables quantification of predator impacts on mollusk populations at ecosystem-wide scales—a methodological leap beyond fragmented, location-specific observations. This ability not only enriches basic ecological knowledge but also equips managers with actionable insights into shellfish populations vital for habitat restoration and commercial aquaculture.

The system’s effectiveness extends beyond controlled laboratory settings. Tested in real-world conditions, including data from animal-borne acoustic tags and fixed underwater sensors, the AI framework reliably identified feeding events and prey types in natural habitats. Its resilience when trained exclusively on tank data yet performing accurately in the field demonstrates robust generalizability, critical for widespread application.

Further intriguing is the framework’s capacity to elucidate predator behavior. According to Dr. Matt Ajemian, senior author and director of the Fisheries Ecology and Conservation Lab at FAU Harbor Branch, the acoustic signatures not only reflect prey species but also reveal handling techniques and processing durations. This opens potential avenues for scientists to distinguish between individual feeding strategies and even estimate prey size categories from subtle variations in shell-crushing sounds.

As global investments in shellfish aquaculture and coastal restoration intensify, tools that effectively monitor predator-prey interactions grow increasingly vital. Considering the diverse prey types analyzed range from buried filter feeders to agile mobile shellfish, this AI-powered acoustic monitoring system emerges as a versatile instrument for tracking mollusk mortalities and ecosystem health across heterogeneous coastal environments.

Finally, the computational efficiency of GTCC-based detection models is especially advantageous for deployment on autonomous underwater platforms constrained by limited power and processing resources. This capability supports extensive, real-time ecological monitoring in remote marine areas where traditional sensor networks are impractical, heralding a new era in marine ecology research.

The research represents a collaborative effort among scientists at Florida Atlantic University, including Ph.D. candidates and faculty from the College of Engineering and Computer Science, highlighting the power of interdisciplinary approaches to address complex ecological challenges with innovative technological solutions. Funded partially by the National Science Foundation and institutional grants, this work exemplifies how AI and acoustic technologies can transform environmental conservation, providing a vital toolkit for safeguarding marine ecosystems under increasing anthropogenic pressure.

Subject of Research: Animals

Article Title: Evaluation of a signal processing and machine learning framework to detect and classify shell-crushing predation events

News Publication Date: 7-May-2026

Web References:

• Florida Atlantic University: https://www.fau.edu/
• Ecological Informatics Journal: https://www.sciencedirect.com/science/article/pii/S1574954126002013

References:

• DOI: 10.1016/j.ecoinf.2026.103795

Image Credits: FAU Harbor Branch, Cat Nickell and Conrad Pfalzgraf

Keywords

Artificial intelligence, aquatic animals, natural resources conservation, sustainability, wildlife management, engineering, technology, acoustics, sound, underwater acoustics, wildlife, predators, marine conservation, ecological restoration, ecosystem management