NOAA biologist Jeff Seminoff, leader of the Marine Turtle Ecology and Assessment Program, examines the belly of an Eastern Pacific Green Sea Turtle in Seal Beach National Wildlife Refuge Seal Beach, CA, on Thursday, May 16, 2019. NOAA set up a net to catch and examine the sea turtles. Photographed under the authority of NMFS ESA Permit number 18238. (Photo by Jeff Gritchen, Orange County Register/SCNG)
SEAL BEACH — Biologists from the National Oceanic and Atmospheric Administration were out in a small channel at the Naval Weapons Station Seal Beach on a recent cool and windy day watching for signs of an entangled Eastern Pacific green sea turtle.
Entanglements don’t typically thrill biologists, but these planned net captures were key to their research.
The threatened green turtles live and forage on eelgrass within the nearly 1,000-acre Seal Beach National Wildlife Refuge, the only such refuge on a military installation in the nation.
The Navy and NOAA are studying the sea turtles as part of a proposed $150 million naval project to relocate the base’s ammunition wharf. The reconfiguration would provide greater installation security and improve safety for private boaters and nearby communities. The 5,000-acre base is responsible for weapons storage, loading and maintenance for ships of the United States Pacific Fleet.
Construction could begin by the end of the year, pending final approvals, with completion by 2025.
On this particular day, three sea turtles were caught in large nets draped underwater and stretched across a small entrance channel near the Seventh Street pond. The channel is part of a network of water that stretches across the southern end of the base and flows beneath Pacific Coast Highway to Huntington Harbor and then into Anaheim Bay.
Jeff Seminoff, marine ecologist and leader of the NOAA’s Marine Turtle Ecology and Assessment Program at the Southwest Fishery Science Center in La Jolla, and his team, are working with Navy biologists to study the turtles’ habitat and lifestyle.
For now, the sea turtles travel along the channel into the bay and to the ocean, but the Navy’s project would change their route.
Officials at the base, which provides ammunition to about 40 ships a year, want to dismantle the more than 60-year-old ammunition wharf and build a new ammunition pier in a different location. Naval operations are limited by the condition of the existing wharf. The Navy expects to service more ships once the new project is done.
The new pier would allow larger ships to more safely enter Anaheim Bay for loading and unloading. The project also would create a new public boat navigation channel farther from Navy operations and would move ammunition loading away from Pacific Coast Highway, increasing safety for nearby communities, said Gregg Smith, spokesman for the naval base.
Seminoff and other NOAA biologists expanded turtle research at the base starting in November 2018. Collected data will be provided to the Navy and the NOAA Regional Office, which is in charge of issuing permits for construction and channel reconfiguration in the refuge and greater Anaheim Bay.
The scientists are studying the sea turtles’ health, the proportion of juveniles to adults, their gender breakdown, and their movements and foraging habits around the bay.
“We’re working collaboratively on determining how that will change with the proposed project,” said Bob Schallmann, a Navy biologist. “The question is we don’t know how long it will take them to figure out the new configuration.”
Currently, the turtles travel from the ocean to the northeast end of Anaheim Bay, then head southeast and follow the channel, finally turning east and passing under the Pacific Coast Highway bridge — a total distance of about 1.3 miles. The proposed channel would follow the lower jetty and turn east under the PCH bridge, a distance of just under one mile.
The green sea turtles, which for the last few decades could be found in San Diego Bay, have expanded their territory into Orange and Los Angeles counties in recent years. Protected bays — such as those at the naval base — have become homes.
The turtles come from nesting beaches off mainland Mexico or from nearby islands there. The biggest green sea turtle nesting population is found off Michoacan, Mexico, where every year there are about 30,000 nests, Seminoff said.
Seminoff and his team identified the turtles caught Thursday, May 16, as two juveniles — likely under 25 years old — and one adult. Turtles typically live to be older than 100.
Green sea turtles are recognized by their dark shell, a scalloped bottom edge to the shell and soft plump skin. They have gray on the belly and a soft patch on the nose, similar to that of a dog.
All three turtles looked generally healthy, Seminoff said.
One juvenile, however, showed signs of small cauliflower-shape tumors on its left eye and flippers. Researchers first saw these growths on sea turtles in the 1950s in Hawaii and Florida, Seminoff said. This is the first one he’s seen at the Seal Beach base.
“There is a high relationship with stranding and this disease,” he said. “The cause is a giant mystery. It’s likely a manifestation of water quality and habitat quality.”
The turtles were micro-chipped, measured and weighed — at 90, 132 and 156 pounds. Tags were clipped to their flippers and satellite telemetry monitors were attached to their shells, with information to be transmitted to Seminoff’s computer. The $5,000 monitors are paid for by the Navy.
So far, eight turtles have monitors. Seminoff said he would like to tag 10 more.
“We’ll be able to determine the specific seagrass patches that the turtles like for forage and also the sites where the turtles go to sleep,” he said. “We are currently studying to see what areas are most preferred. Once construction starts, we’ll continue to track turtles to see if their home ranges and movements shift due to construction, excessive noise and water turbidity.”
The NOAA and Navy also will study whether there is a greater risk of ship strikes to the sea turtles with the new configuration.