FIDALGO BAY — Armed with binoculars and spotting scopes Thursday, volunteers scanned the choppy waters of Fidalgo Bay, calling out the birds they saw.
They ticked off their counts as part of a new survey to track what types of birds, and how many, are seen in the bay.
The survey began in September at the recommendation of the Fidalgo Bay Aquatic Reserve Citizen Stewardship Committee — a group of volunteers working to ensure that efforts to restore and protect the bay are successful — and the Skagit Audubon Society.
“In case there’s an oil spill or whatever, we want to see what’s going on and watch for trends,” committee member Morty Cohen said.
The survey is being led by Erica Bleke of the state Department of Natural Resources’ Aquatic Reserves Program. Fidalgo Bay is one of eight state aquatic reserves managed by the state agency.
The survey will be done annually from September to May, when most migratory birds are seen in the bay.
Cohen said it will build off of data from when the bay was surveyed years ago and is adhering to previous methods, including using the same magnification power that was available for spotting scopes at that time.
The goal is to monitor the birds long term so that changes in population — such as a decrease due to pollution or an increase that shows the recovery of a species — are more easily recognized.
“We want to gather baseline data so we know what is there and whether to be worried in the future if something happens,” Bleke said.
The group isn’t sure yet which bird species to document through the survey. One of the tasks during the first year is to note all species seen.
So far, surveyors have primarily seen buffleheads — a small diving duck that uses fresh and saltwater habitats — and other species such as bald eagles and teals, another type of duck.
The survey is done once a month during high tides because diving ducks are more active during that time.
This type of survey has been done at the Cherry Point Aquatic Reserve in Whatcom County for five years.
Bleke said the Cherry Point survey data is beginning to offer insight into trends such as what time of year the most birds are seen.
The most birds are seen in that area during May, according to a 2016 report. The birds are believed to be drawn to the reserve at that time because it correlates with the spawning of herring.
Herring is a small forage fish that spawns in shoreline areas and is eaten by many larger fish and marine birds.
Since surveys began at Cherry Point in 2013, brant and surf scoters have been the most abundant bird species, numbering in the hundreds, according to the report.
Compared to data from other surveys done in the area as far back as the 1970s, bald eagle numbers have increased most dramatically, while surf scoter numbers have decreased.
Surf scoters are believed to have declined because of the loss of herring spawning areas due to development on Cherry Point shorelines, according to the report.
Bleke and the stewardship committee said it’s important to have that type of information available for Fidalgo Bay.
“A lot of the habitat in Fidalgo Bay is eelgrass meadows and mudflats and things that are really important for species that are going to be migrating,” Bleke said.