Controls on underwater noise and protections for an area that is a food-foraging hot spot are among the elements of a new five-year, five-part action plan aimed at nudging Cook Inlet's endangered beluga whales toward recovery.

The plan, released Wednesday by the National Marine Fisheries Service, lays out actions the agency plans to take over the next five years -- as long as funding is available and cooperating agencies participate. The action plan is part of a broader program, including a recovery plan, aimed at improving prospects for a population that continues to struggle 16 years after formal protections were granted to it.

"The action plan for Cook Inlet belugas will go a long way in helping us secure the partnerships and support that we need to recover this extremely vulnerable species. Together with the Draft Recovery Plan, it is a roadmap to help ensure this species has a fighting chance," Mandy Migura, a marine mammal biologist for NMFS' Protected Resources Division, said in an email.

Cook Inlet belugas were designated in 2000 as depleted under the Marine Mammal Protection Act. They were listed as endangered eight years later.

A big focus of the new action plan is noise -- determining how much exists in the waters off Alaska's biggest city and most populous region, how it affects the belugas and how it may be reduced.

Noise is not a new concern, and has been cited in past studies and management documents, Migura said. But the action plan seeks to broaden existing noise studies.

It calls for year-round monitoring to determine background levels in the Inlet. For now, funding is available for such monitoring for only one year, and only in the Susitna River delta area, a site known to be important to the belugas. But such work should continue until Cook Inlet belugas recover to the point where they are delisted, the action plan says.

Seasonal restrictions on noisy activities might be appropriate for the Susitna River delta, a site where belugas are known to congregate to eat salmon and eulachon, the action plan says.

That is a logical place for protections, Migura said. The delta is where "several hundred belugas may be found" during the summer, she said.

She noted that a new study identifies the area as a potential calving ground. That study, presented at last month's Alaska Marine Science Symposium, tracks the past decade's worth of sightings in that area of newborns and their mothers.

The plan also calls for beefed-up procedures to respond to beluga strandings. For example, NMFS is seeking better equipment to gather information when dead belugas are found. For now, "most necropsies of Cook Inlet beluga whales are done in the field and generally are limited by access to the carcasses and the dangerous environmental conditions," the action plan says.

An improved stranding program would also include enhanced public participation, with citizens reporting strandings of live and dead whales and helping gather scientific data, the action plan says.

Other elements of the action plan address studies of fish that belugas eat, more formalized protection of critical habit and better understanding of population dynamics.

Aerial population surveys have been conducted since 1993; the last survey, in 2014, yielded a population estimate of 340. The surveys are now conducted on a biennial basis, with the next planned for this coming June.

Another type of monitoring, which produces photographs of individual whales, has been conducted since 2005. Another photo-identification survey is planned this summer, and NMFS also plans to add a biopsy program to that, the action plan says.

NMFS also issued action plans for seven other protected marine populations that are "among the most at risk of extinction in the near future," according to a NMFS statement. Those were three specific Lower 48 salmon populations along with populations of Hawaiian monk seals, Pacific leatherback sea turtles, southern resident killer whales of the Pacific Northwest and white abalones.