Oyster farms' ecosystem services in improving water quality are "not typically considered within the aquaculture permit review process," according to NOAA, whose new calculator aims to address this gap.
Image: NOAA
A newly developed online calculator, the Aquaculture Nutrient Removal Calculator, is set to enable oyster farmers to more accurately assess the environmental benefits of their aquaculture operations.
Created by scientists from NOAA's Northeast Fisheries Science Center and the National Centers for Coastal Ocean Science, the tool, based on a large dataset that covers the size of oysters and nitrogen concentrations from Maine to North Carolina, provides a science-based estimate of how much nitrogen oyster farms remove from local waterways.
“We've heard from both regulators and industry members that they need a simple, intuitive way to calculate the environmental benefits shellfish aquaculture provides,” said Julie Rose, project lead and research ecologist, in a NOAA news release.
"We're excited to share our tool, which synthesizes data collected by excellent scientists from around the region, to create a robust prediction of nitrogen removal that industry members and regulators can have confidence in.”
Nitrogen is a vital nutrient, but excessive levels from sources such as fertilizer run-off from arable land can lead to oxygen-deprived "dead zones" and harmful algal blooms in coastal waters. Oysters help mitigate these effects by filter-feeding on algae, which contain nitrogen, thus improving water quality, NOAA explains.
However, these environmental benefits - also known as ecosystem services - are often overlooked in the permitting process, NOAA officials point out, emphasizing that the new calculator aims to fill that gap.
The NOAA team that created the Aquaculture Nutrient Removal Calculator. (Left to right) Oceanographer Ryan Morse, Marine Ecologist Chris Schillaci, and Research Ecologist Julie Rose.
Photo credit: Lynn Fantom / NOAA.
The Aquaculture Nutrient Removal Calculator is designed for oyster growers in the Northeast United States, allowing farmers to input data such as the number of oysters harvested, their size, and other farm details.
Basedd on this, the online calculator generates a report estimating the nitrogen removal provided by the farm, and including citations for regulatory purposes, which can be used in the aquaculture permitting process. This science-backed estimate is a valuable addition to applications for regulatory review by aquaculture permit organizations like the U.S. Army Corps of Engineers or state agencies, NOAA states.
According to NOAA, the tool could also help shellfish growers build greater awareness of the environmental benefits of their farms within local communities and among regulators.
NOAA plans to expand the calculator's capabilities to estimate phosphorus removal, another key nutrient, and develop a similar tool for assessing the essential fish habitat benefits that shellfish farms provide. The project team say they plan to use data gathered from the GoPro Aquaculture Project, which has collected more than 1,600 hours of underwater video on shellfish farms and rock reef comparison habitats in Long Island Sound.
This work is expected to broaden the tool’s scope, extending its use to other bivalves like clams and mussels.
NOAA is also hoping to expand the area covered to include the Gulf of Mexico.
A virtual workshop to introduce the Aquaculture Nutrient Removal Calculator will be held by Connecticut Sea Grant on November 21, 2024, providing growers with the opportunity to learn more and offer feedback on the tool.
