The overall objective of this project was to demonstrate the abilities of the Automated Benthic Ecology System (ABES) to obtain a wide-range of regulatory-required data in areas that could be difficult for human divers. The specific technical objectives of the project were: 1) to demonstrate that ABES can enhance the Department of Defense's (DoD) benthic survey and monitoring protocols; 2) demonstrate a sampling protocol and technical transition plan for target users; and 3) demonstrate cost savings of ABES over traditional diver-based methods.
The project team tested the efficacy of ABES in the context of two applications: 1) assessment of overall benthic community structure on a man-made dock and its surrounding seafloor at the Pearl Harbor Naval Shipyard and Intermediate Maintenance Facility (PHNSY & IMF); and 2) assessment of coral metrics on a man-made structure under National Marine Sanctuary oversight at Naval Air Station Key West (NAS KW). The PHNS & IMF sites exemplified areas where military construction (MILCON) efforts will occur to lengthen and widen existing drydocks to accommodate for the larger class of Naval vessels. The NAS KW sites exemplified areas where MILCON, dredging, and placement of temporary structures need to occur within a national marine sanctuary. As such, stricter data ecological data requirements for compliance at NAS KW are enforced. To evaluate the potential benefits and costs of ABES, the project team compared ABES’s integrated approach with that of traditional methods for benthic assessment.
In particular, the project team assessed the effectiveness of ABES to 1) retain strengths of diver-based expert observations for benthic cover and species richness (Performance Objective 1); and 2) increase the efficiency of benthic surveys, both in terms of time and costs (Performance Objective 2). Performance Objective 1 consisted of two metrics assessed at the four different sites chosen for the PHNSY & IMF demonstration and six metrics assessed at the six different sites chosen for the NAS KW demonstration. Performance Objective 2 consisted of two metrics collected at both the PHNSY & IMF and NASKW sites. Comparison of the operational costs for both ABES and traditional methods (cost/m2 of area surveys served per metric) was the basis for cost-benefit analysis.
ABES integrates photomosaicking techniques and an environmental suite onto an underwater Remotely Operated Vehicle (ROV) that navigates with high Global Positioning System accuracy while interrogating vertical surfaces and seafloor areas. This work leverages several capabilities previously funded by a variety of sponsors:
Two field demonstrations were conducted to evaluate a total of ten metrics under two performance objectives.
The PHNSY & IMF demonstration consisted of assessing benthic coverage of coral, turf algae, macroalgae, crustose coralline algae, milleporans, gorgonians, zoanthids, sponges, various substrate types, and rugosity measurements using two different methods for Performance Objective 1. The imagery data obtained by ABES was used to calculate these metrics from a variety of software packages. Field data were obtained by Navy Scientific Divers (NSDs) using traditional benthic ecology survey methods. The time to obtain the data in the field and the time to analyze the products produced by the different methods was tracked for Performance Objective 2. The results showed that ABES can retain the strengths of diver-based observations for all metrics under Performance Objective 1. The results from Performance Objective 2 showed that the time taken for ABES to acquire data and the time taken to analyze ABES products were not significantly different than those of the diver-swum methods.
The NASKW demonstration consisted of assessing species richness, coral and sponge length, width and height measurements, percent disease of corals and sponges, and rugosity measurements in fulfillment of Performance Objective 1. The imagery data obtained by ABES were used to caclulate these metrics from using a variety of software packages. Field data were obtained by NSDs using a modified national marine sanctuary protocol. The time to obtain the data in the field and the time to analyze the products produced by the different methods was tracked for Performance Objective 2. The results showed that ABES can retain the strengths of diver-based observations for most of the metrics analyzed under Performance Objective 1. The results from Performance Objective 2 also showed that the time taken for ABES to acquire data and the time taken to analyze ABES products were significantly different than those of the diver-swum methods, with ABES being cheaper and faster.
ABES is found to be a superior approach under the following conditions:
The environmental compliance community is the intended end-user for ABES, specifically targeting at-sea range managers within the DoD. ABES can provide valuable datasets to be used in all types of environmental compliance documents, from Integrated Natural Resource Management Plans to Environmental Impact Statements. ABES can also supply valuable data for MILCON and alternative energy projects by performing benthic ecosystem surveys of pier and quay walls, navigational buoys, at-sea runway warning light structures, underwater wreckages, and other engineering applications. ABES is well suited to assess benthic communities growing on navigational buoy anchors and chains for the U.S. Coast Guard, and also has the potential to be used to detect leaks/cracks in quay and pier walls for structural integrity assessments. NIWC Pacific continues to work with the Explosive Ordnance Disposal community on the wreck identification work started under NESDI Project 521 and with Navy Range managers for future evaluations of unexploded ordnance, specifically in areas like Puerto Rico, where corals are growing on munitions components. Currently, no other single protocol exists that encompasses fish transects, benthic transects, rugosity measurements, and water quality measurements all in one survey to produce high-resolution photomosaics, 3D models, and stereoscopic data products. Due to the unique capabilities of ABES, a U.S. Patent was granted (U.S. Patent No. 11,080,821 B2 dated August 3, 2021).