A group of oil companies and geophysical contractors is sponsoring development of a software program designed to improve the detection of marine mammals near seismic surveys and in underwater activities requiring explosives.
Permits for offshore seismic surveys often require contractors to have qualified biologists or other trained observers aboard survey vessels to determine the presence of marine mammals that might be harmed by seismic shots.
The animals, which include whales, dolphins, porpoises, dugongs, manatees, seals, and sea lions, must be at least 500 m from seismic operations in most cases.
Seismic surveys are expensive, and false sightings that delay operations are costly. In addition to visual equipment, such as laser range-finding binoculars and video ranging automatic systems, observers can use passive acoustic monitoring (PAM) software with two hydrophones to detect the whistles, clicks, thumps, moans, “songs,” and other sounds animals make to communicate, locate food, and navigate.
PAM systems have a major limitation, however: They can provide data identifying the angular direction, or bearing, of a vocalizing animal from the point of observation but not its distance away, or range. Work toward a solution to that problem is limited because the source code of PAM software is not freely available. However, a solution is now at hand.
Pamguard
To address the limitations of PAM systems, Heriot-Watt University, Edinburgh, is hosting development of a software program called Pamguard with the backing of the International Association of Geophysical Contractors (IAGC) and the support of Ecologic, a Scottish consultant.
A group of oil companies, the Industry Research Funders Coalition (IRFC), is providing funding for the initial phases of development. IRFC includes BHP Billiton Petroleum (Americas) Inc., BP Exploration & Production Inc., ChevronTexaco Exploration & Production Co., ConocoPhillips Co., ExxonMobil Exploration Co., Shell Exploration & Production Co., and members of IAGC.
The Pamguard software is being developed as an integrated PAM software structure that will be “open source” (publicly owned and available at no cost to PAM users), reported Paul Redmond, one of the Heriot-Watt project directors. He said it will work much like existing PAM software, such as Ishmael, Rainbow Click, and Logger, and be usable on multiple operating systems such as Windows and Linux.
It also will be able to incorporate new modules as they are developed “to include additional detection, localization, classification, and sound visualization functionalities.”
The software is being designed to provide flexibility in the number of hydrophones used, sensitivities, spacing, and geometry, Redmond said.
Scheduling
In the first phase of development in 2004, Heriot-Watt created a web site (www.pamguard.org) to gather field experiences and user requirements and established an administrative center where software architecture would be developed to provide usage standards for the passive acoustic detection technology.
Heriot-Watt was fully funded in 2005 to develop up-to-date software applications with vocalization detection, navigational-mapping, and data logging, all compatible with existing software applications that use a two-element towed hydrophone array.
In 2006, Pamguard software will contain additional detection and 3D localization methods that currently are being developed as part of the sperm whale seismic study (SWSS) research program in the Gulf of Mexico, which the US Minerals Management Service is funding. SWSS involves researchers from Ecologic with support and cooperation from IRFC and IAGC, along with nine universities and governmental research foundations.
Aaron Thode of Scripps Institution of Oceanography, San Diego, and David Mellinger of Oregon State University are developing this function. Mellinger also has received funds to complete the updating of Ishmael to Linux by early 2006 and to build a Logger capability. Ishmael will then be implemented in Java as part of Pamguard.
Jonathan Gordon of the Sea Mammal Research Unit, St. Andrews University, is providing a practical marine mammal acoustic monitoring perspective for the project, and Doug Gillespie, the author of much existing PAM software, is assisting with overall program architecture and the implementation of algorithms from existing click and whistle detection programs into the Pamguard framework.
The Pamguard software application is expected to become a standard user interface that will benefit all PAM users and will be a catalyst for modernizing and standardizing all PAM technology.
