Spectral detection and monitoring of marine mammals

Abstract

This note presents an airborne spectral imaging system and methodology used to detect, track and monitor marine mammal populations. The system is a four band multispectral imaging system using spectral bands tailored for maritime imaging. This low cost, low volume, imaging sensor can be deployed on either a small unmanned air vehicle (UAV) or any other cost efficient aircraft. Results of recent multispectral data collects over marine mammals in St. Lawrence Seaway are presented. Species present included beluga whales as well as various species of larger baleen whales. OBJECTIVESTo develop an electro-optical system that will both search for and determine the presence of whales and verify radar or acoustic detection. Finally, to identify potential data products useful to both military and non-military users in marine mammal research and inventory projects. BACKGROUNDCurrent Naval Acoustic Anti Submarine Warfare (ASW) readiness requires the nearly continual testing of new active acoustic systems and tactics as threat profiles constantly change. This testing introduces high decibel (dB) sound into the water column at frequencies utilized by nearby marine mammals. This high dB sound has the potential to disorient or directly harm these animals thus arguably making active acoustic system testing a violation of the Marine Mammal Protection Act. A testing program that actively seeks to avoid exposing marine mammals to high dB noise is thus desired. The end goal of this program and others like it is to better understand marine mammal migrations and behaviors, investigate a wide collection of marine mammal detection systems and document their detection performance, and determine the interconnectivity of these systems in ASW acoustic testing.Advanced Coherent Technologies, LLC (ACT) is performing work under SBIR Topic: N07-019 "Whale Search Radar" in support of the Naval Airfare War Center and ASW military testing and training activities involving midrange sonar (AN/SQS-53C and AN/SQS-56). This agreement between parties allows scientists and engineers to further develop mitigation management protocol that conform to the National Environmental Policy Act (NEPA), 42 U.S.C. § 4321 et. Seq., and the Coastal Zone Management Act (CZMA), 16 U. S. C § 1451 et seq.Research activities are on-going in the investigation and development of an electro-optical (EO) system that will image whales with sufficient resolution to detect and classify them in a timely fashion. The goal is to combine the EO imagery with computer aided detection software in the development of algorithms and methods for detecting whales such that the NAVY may eliminate and/or mitigate any damage to the whales during sonar operational exercises. These technological advancements safeguard the protection of marine environments through enhanced mitigation measures derived from near real-time data analyses and product delivery. Most importantly, our research seeks to demonstrate how passive remote sensing and detection and prediction through strategies derived from quant...

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