Supplemental EIS evaluates risk that Bangor construction could pose for endangered marbled murrelet
October 28, 2011 · 1:43 PM
The shores and old-growth forests surrounding Hood Canal are a natural habitat of the endangered marbled murrelet, a small-bodied seabird which is protected under federal law. This area is also the site designated for Navy construction of a second explosives handling wharf to support the Trident D-5 Missile program.
Concerns for the safety of the marbled murrelet are causing the Navy to proceed with caution.
After the release of the original DEIS in 2009, the Navy determined the need to take a second look at how high underwater noise frequencies caused by shore construction could injure the marbled murrelet species.
“Section 7 of the [Endangered Species Act] requires that all federal agencies to enter into consultation with U.S. Fish and Wildlife Service and National Marine Fisheries Service whenever proposed projects may affect threatened and endangered species of plants or animals,” said Sheila Murray a public affairs officer for the Navy.
The proposed EHW-2 project will cost $750 million and involve demolition of some existing structures and pile driving to create the facilities to help maintain and support D-5 missiles.
The effect of such hammer strikes have been evaluated in other marine mammals and birds, but not the marbled murrelet. The lack of data specific to this case presented a challenge. In other species, high impact underwater frequencies have been linked to irreversible inner ear cell damage.
According to Emily Teachout, U.S. Fish and Wildlife biologist and species lead for the marbled murrelet, such damage would impact not only murrelet hearing but behavior, the ability to forage for food, and ultimately the species ability to survive.
Teachout explained that Washington has seen a decline of 50 percent of its marbled murrelet population in the last ten years alone.
“It’s a population where every bird counts,” said Doug Zimmer, supervisor of Information and Education for the USFWS.
The Navy responded to the concern by assembling the Marbled Murrelet Science Panel in cooperation with the USFWS. The group included subject experts from avian hearing, murrelet ecology, and underwater sound.
The panelists faced the unique challenge of applying their area knowledge to a species who has never been tested for those variables. There is no definitive authority on marbled murrelets or their reaction to damaging noise impact.
“There is no existing expert on underwater impulse noise and its specific effects on murrelets. That data just doesn’t exist,” said Teachout.
She explained that in light of limited information, the panel faced the huge task of creating a defensible criteria for risk.
During the sessions, experts considered data on impulse sounds similar to that of pile driving such as explosions or seismic testing. Later continuous sounds like sonar were also considered.
A hierarchy of animal species was also created. The panel pooled research on comparable diving sea ducks, other small-bodied birds, marine mammals, and even sea turtles and documented behavior to acoustic effects. Then they had to extrapolate from the literature.
“Nothing was a perfect match,” said Teachout.
Still, the Department of the Navy is relatively confident that they have located an acceptable threshold of injury. The current study looks at harm in determining the lowest level of injury possible only. It does not go into the consequences of noise harassment which has more variables. In addition, executing proper monitoring of the marbled murrelets is key.
“Injury to marbled murrelets could occur if they were within the injury zone when piles were driven with an impact hammer,” said Murray.
Teachout adds that though murrelets are “shy, cryptic birds,” they display an overwhelming drive to forage their territories for food. This could prove a wild card in monitoring.
“It’s possible that [the murrelets] don’t feel the damage of the noise impact, and swim closer to the pile driving regardless of the damage it does to them,” she said.
The Navy has proposed bubble curtain to reduce underwater noise, zones of injury, and monitoring of the murrelets.
“If these species are seen within the injury zones, the Navy will stop pile driving and will not resume driving with an impact hammer until these species move outside of the injury zone,” said Murray.
Jim Ullrich of the Kitsap Audubon Society observes the huge task that the Navy has before them.
“These officers and senior enlisted have so many things to be responsible for with keeping this beautiful area pristine and also following the rules,” he said.
He recalls how different the building of the original EHW-1 was back in the 1970s.
“Back then, the damage was big, but then there wasn’t the same awareness of environmental issues as today.”
Vern Rutter of the Hood Canal Environmental Council adds, “[The Navy] is serious about doing the right thing, and there’s a long history of that.”
The Navy welcomes all comments from the public regarding the construction of the second explosives handling wharf.
The complete supplemental Draft EIS is open to the public at https://www.nbkeis.com/ehw/. Public comments are open until Nov. 21.