After receiving numerous reports about a sharp mortality increase in two different endangered species of sturgeon in the Hudson River, a federal agency is taking another look at possible dangers posed to the fish by the construction of the new Tappan Zee Bridge.
The National Marine Fisheries Service, which is affiliated with the National Oceanic and Atmospheric Administration, has begun a new analysis of the bridge project”™s work vessels, which had previously been written off by the agency as posing no threat to sturgeon life in the river.
Julie Crocker, the regional endangered species coordinator for the National Marine Fisheries Service, said in email that the agency is working with the Federal Highway Administration, the lead federal agency for the bridge replacement project, to analyze the operations of all Tappan Zee project vessels.
This effort, she said, will help “determine what measures can be implemented at the project to reduce the risk to sturgeon from project vessels.”
Crocker also said that the agency, the state of New York and the bridge contractors have carried out the monitoring and reporting requirements for dead or injured sturgeon since the project started.
From 2013 to 2014, 68 sturgeon were reported dead or injured within 15 miles of the bridge replacement project, up from a combined 21 reported in the same area between 2007 and 2012.
Riverkeeper Inc., an Ossining-based environmental organization, obtained that information from the state Department of Environmental Conservation through a Freedom of Information Act request.
The new Tappan Zee Bridge, which is estimated to cost nearly $4 billion, started pile installation testing in 2012 and began construction in 2013. About three dozen propeller-powered vessels are used to do work on the new bridge, which is expected to be finished and the bridge fully open to the public in 2018.
Riverkeeper and the Pace Environmental Litigation Clinic, the attorney group with Pace University School of Law that represents Riverkeeper, included the sturgeon mortality data in a July 9 letter to the National Marine Fisheries Service in Massachusetts. The letter urged the agency to reinvestigate “the extent to which reported increases in sturgeon mortality must be assumed to be related to Project construction activities.”
Karl S. Coplan, co-director of the Pace clinic and one of the lawyers representing Riverkeeper in the petition, said, “The numbers speak for themselves. It”™s hard to look at this and not have a strong conviction that the bridge activity has played a role in the increased sturgeon mortality.”
Jennifer Givner, a spokeswoman for the state Thruway Authority, said those involved in the bridge project are working with state and federal agencies to look into the concerns made by Riverkeeper.
“Since construction began, the project team has taken unprecedented measures to protect endangered sturgeon and other aquatic life in the Hudson River, including the use of bubble curtains during pile driving to reduce underwater noise, extensive sturgeon monitoring, tracking and habitat studies,” Givner said in an email.
Because Atlantic sturgeon and shortnose sturgeon are endangered species, the Thruway Authority had to obtain a permit from the National Marine Fisheries Service to do work in the river that included terms and conditions to help mitigate the construction impact on the fish.
As part of the agreement for the permit, the project could not be responsible for more than two sturgeon of each species dying during dredging or pile driving during the five years of the bridge”™s construction.
In addition, the agency assumed ”” based on previous studies, sturgeon spawning patterns and the nature of the Hudson River ”” that “the increased vessel traffic associated with the Tappan Zee Bridge replacement is not expected to result in direct interactions with sturgeon,” according to the most recent biological opinion issued by the agency in 2014.
As a result of the scientific information being gathered by the agency as it reinvestigates the relationship between sturgeon and the bridge project”™s vessels, a new biological opinion may be issued with new terms and conditions that the Thruway Authority and bridge contractors must adhere.
Crocker said a new biological opinion is expected this winter.
