Network Data Collection Instruments:

The role of passive acoustic monitoring (PAM) in AEON is to provide long-term observations of human and biological activity as well as changes in environmental conditions in support of all four AEON Objectives. PAM information has a wide variety of uses including documenting the temporal-spatial distribution of vocalizing marine life, quantifying the natural variability of and human induced effects on the soundscape, and providing reference soundscapes for comparison to noise models. At each network site, AEON employs the latest generation of JASCO’s AMAR recorder mounted on an Autonomous Long-Term Observatory (ALTO) lander with ancillary sensors.

JASCO ALTO lander with AEON acoustic measurement instruments

Active Acoustics. To assess the spatial and temporal distribution of the soundscape and biological scatterers, including their expected variation and correlation with distance from the observation points, small (6-10 km2), spatial surveys at each lander site will be conducted using a multiple frequency, broadband fisheries echosounder system (EK80 operating at 38, 70, 120, and 200 kHz).  The vessel-based and lander echosounder (Acoustic Zooplankton Fish Profilers, ASL Environmental Sciences) systems operate at the same four frequencies.  The echosounder surveys conducted at each lander site during the deployment and recovery cruises will provide  information on the spatial structure of water column scatterers (in both the vertical and horizontal dimensions) and how organism patchiness will vary in both time and space.  This information will be critical to properly interpret the long time-series data from upward-looking echosounder data collected by each lander.

In order to ground truth the acoustic backscatter data, it is necessary to collect physical specimens of the organisms present in the water column using a combination of vertical ring net tows and midwater trawls.  During each survey, a small ring or bongo-style net will be vertically hauled through the upper 25 to 100 m of the water column.  This will collect samples of meso- and macro-zooplankton, primarily animals like copepods, crustaceans, gelatinous organisms, shelled pteropods, etc.  These animals can scatter significant quantities of sound at higher frequencies and are often aggregated along oceanographic features such as fronts or pycnoclines.

High resolution temporal and vertical sampling of the water column is required.  To combine high-rate bottom-mounted acoustic measurements with a separate dedicated vertical sampling mooring, a profiler, the DelMar Oceanographic Wirewalker with a combination of bio-optical (chlorophyll, turbidity, scattering), metabolic rate (O2), and CTD sensors will be deployed to provide profiles from the surface to 50 m every 10 minutes.  The deployment approach will be to operate the profiler for 1-2 months in summer and winter periods near an established AEON site.

Products of Research

The data to be collected during this project include; raw data and products or models created through data analysis.

AEON Dataset categories by Team Responsibility

Data Type

Related Activities


Raw Data Collection

Lander acoustic backscatter

UNH - Miksis-Olds

Ship acoustic backscatter

Stony Brook - Warren

Zooplankton ship sampling

Stony Brook - Warren

Passive acoustic omni and directional data

JASCO - Martin

Hydrographic data

UNH – Vandemark, JASCO - Martin

Compiled or Derived Data

Soundscape modeling output

AOS - Heaney

Acoustic backscatter datasets from bottom-landers and ship sampling

UNH – Miksis-Olds, Stony Brook - Warren


Soundscape spectra and decidecade levels

JASCO - Martin


Marine mammal detections and density estimation

JASCO - Martin