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Marine Wildlife Observation: Part of a Day's Work

Dredging and marine construction are vital activities that maintain our nation’s waterways. However, an important yet lesser-known aspect of these projects is monitoring and protecting endangered marine life. For Manson’s project crews, looking out for sea turtles and other threatened or endangered species is part of a day’s work.

Manson works with third party subcontractors to provide a certified Endangered Species Observer (ESO) on each project. On our Gulf and East Coast Dredging projects, the ESO monitors the water from the vessel’s bridge for a sign of any of the five species of sea turtles (green turtle, hawksbill, Kemp’s ridley, leatherback, and loggerhead) that populate the Gulf of Mexico and the Atlantic Ocean off the South Atlantic Coast. According to Lisa Rodriguez, an ESO who has worked on numerous Manson dredging projects, some projects require two observers to perform 24-hour observation coverage for the project in shifts.

Since the Endangered Species Act of 1973, the U.S Army Corps of Engineers (USACE) and the dredging industry have developed protocols and operational methods to successfully reduce dredging impacts to sea turtles. When a sea turtle is spotted in the ocean or caught in the hopper, there is a formal chain of command that must be followed to report the incident and/or get the turtle to safety. The ESO alerts their company, then alerts Manson, who then alerts USACE.

Another form of monitoring comes in the form of trawling which is done prior to dredge performance. The turtle trawler is a modified shrimp trawler equipped with specialized nets to capture turtles and sturgeon – another endangered species seen on hopper dredge projects – clearing the project site so that turtles won’t have the chance to get caught or hit by the dredge. If a marine animal does get spotted or caught, observers check for a tag. If there isn’t one, the sea turtle will be tagged in order to track its movements. The turtle is then relocated to a location several miles away from the project site and released back into water. Identifying individual sea turtles in this manner is critical for understanding nesting behavior and monitoring the sea turtle populations.

To further protect turtles or sturgeon from getting caught in the dredging process, hopper dredges are equipped with screens to prevent them from getting into the drag heads. After every load, the ESO checks the drag head in case it “takes” a turtle, the term used if a turtle is injured.

During beach restoration projects, and depending on the time of year, ESOs also look out for shore birds’ nests – such as piping plovers – as well as sea turtle nests. These creatures often make their nests on the beaches right next to resting dozers left in place overnight. Often observers arrive to the project site in the mornings to find a nest directly next to a dozer as the machines help block the wind.

The ESOs walk up and down the beach looking for nesting activities. Once a nest is found, they cordon off the area and Manson project crews maintain a certain distance from the restricted space.

Jessica Heath, Manson field engineer, has worked on numerous projects where marine animal monitoring was required. She says that what can make marine monitoring challenging, is that “you don’t really know what’s down there until something happens, you are not aware of where they are or how many are there. Turtles will burrow themselves down, or (swim away.)”

If a sea turtle is injured, it is taken a relocation center which is usually run by NOAA or another state agency. Jessica said that three years ago, during the Kings Bay Maintenance Dredging project, (Manson) took a turtle and it survived. “It was taken to the Georgia Sea Turtle Center. They named it ‘Newt,’ short for (Manson’s) NEWPORT.” According to Nicole Thomas, Education Program Manager at the Georgia Sea Turtle Center, Newt “recovered quickly and was released back into the wild at Little Talbot State Park” just a few months later.

Jon Nowak, Manson project engineer, proudly recalls that in 2017, when Manson was working on the Regional Hopper Dredge project for USACE Wilmington District in North Carolina, project crews successfully relocated 80 sturgeon and several sea turtles (see photos). This is an example of the increase in sea turtles spotted on dredge projects, a testament that these methods have been successful, and that sea turtle populations are slowly coming back.

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