Flying for science: Kenmore Air and WDFW’s Midwinter Seabird Survey

Kenmore Air reconfigured one of its de Havilland Turbine Beaver floatplanes for the Midwinter Seabird Survey, replacing seats with specialized cameras mounted to the floor of the aircraft to capture high-resolution, georeferenced imagery of the water’s surface below. Photo by Kenmore Air.

On a series of crisp winter mornings in the Pacific Northwest, when the water is glassy and the shoreline feels almost still, a signature Kenmore Air turbine beaver seaplane lifts off from Lake Washington headed toward the waters of Puget Sound. There are no traditional passengers onboard; no phone cameras angled at the skyline, no scenic narration through a headset.

Instead, the mission is scientific.

For decades, Kenmore Air has partnered with the Washington Department of Fish and Wildlife (WDFW) to support the Midwinter Aerial Seabird Survey, a critical, long-running effort to monitor the health, abundance, and distribution of marine birds across Washington’s Salish Sea. This work plays an essential role in how Washington manages and protects its inland marine waters.

This past winter, Kenmore Air once again took to the skies alongside WDFW biologists, this time helping advance a new, more precise approach to seabird monitoring that blends aviation expertise with cutting-edge technology.

A survey rooted in place and time

Brant feed on floating eel grass along a tideline in Samish Bay. Digital aerial surveys have informed management decisions around the Skagit County brant hunt over the past two years with greater accuracy than previous survey techniques. WDFW photo.

Washington’s midwinter seabird surveys date back to the early 1990s. Designed to capture a snapshot of marine bird populations during the heart of winter, the surveys focus on a critical window when sea ducks and other marine birds are least likely to be migrating. “Seabirds” refers to several bird groups that depend on the marine environment for some part of their annual life cycle, including ducks, geese, grebes, loons, murres, and more.

WDFW and Kenmore Air conduct these surveys in the winter because this is when the Salish Sea tells its most honest story. During these months, birds settle into predictable patterns tied to food availability, water depth, and habitat. By surveying consistently at the same time each year, biologists can track long-term trends, spotting population changes, identifying areas of concern, and informing wildlife management decisions that ripple far beyond the water’s surface.

Seabirds weren’t the only species observed during the surveys. Here, a raft of sea otters float in a kelp forest near Neah Bay. Harlequin ducks and gulls were also identified in this image. WDFW photo.

The survey is flown along nearly 3,800 kilometers of transect routes, distributed throughout Washington’s Salish Sea waters to systematically sample nearshore and offshore habitats. It’s an ambitious undertaking, one that requires precision (flying at 860 feet and a ground speed of 105 knots), consistency, and a deep familiarity with the region’s complex terrain. That’s where WDFW’s partnership with Kenmore Air comes in.

Why aviation matters in wildlife science

WDFW biologists adjust their survey monitors and equipment prior to a survey flight. Photo by Kenmore Air.

Counting seabirds from the air is not simply about flying low and looking out the window.

Historically, the surveys relied on experienced biologists visually identifying and counting birds from both sides of an aircraft flying approximately 200 feet above the water at 85–90 knots. Each observer focused on a defined strip of water along their side of the plane, calling out sightings in real time.

It’s a demanding process, and one that requires steady flight, excellent visibility, and close coordination between pilots and biologists. Winter conditions add another layer of complexity thanks to shorter daylight hours and shifting weather systems.

Kenmore Air makes this work possible by providing aircraft, pilots, and operational support capable of flying safely and consistently even in difficult conditions. Meanwhile, skilled WDFW biologists use their expertise in wildlife surveying and species identification to collect data during the flights.

This winter, the survey took an important step forward.

A new chapter: digital aerial surveys

The camera setup used to capture high-resolution digital images along set transects throughout Washington’s Salish Sea. Photo by Kenmore Air.

In partnership with WDFW and the Puget Sound Ecosystem Monitoring Program (PSEMP), Kenmore Air supported the deployment of a Digital Aerial Survey (DAS) system, an approach that uses high-resolution imaging, GPS-linked data capture, and machine learning to enhance how seabirds are documented and analyzed.

With traditional passenger seats in one of Kenmore’s seaplanes removed, digital cameras were mounted with a removable panel so that the DAS system captures imagery of the water below. Each image is precisely time-stamped and georeferenced, creating a permanent visual record of the survey area.

What once relied solely on human observation can now be reviewed, verified, and re-analyzed, allowing scientists to:

• Improve species identification accuracy
• Eliminate most uncertainty around species count and classification during surveys
• Revisit historical data as analytical tools evolve
• Expand survey coverage without increasing risk

The result is a richer, more resilient dataset, one that strengthens long-term conservation planning.

Large, mixed-species flocks were difficult to survey in the past, even for trained observers. During traditional ocular aerial surveys, an observer had only a second or two to identify species and estimate the number of individuals in a flock. Now, using high-resolution imagery and machine learning, WDFW biologists can detect individual birds, identify them to species, produce highly accurate counts, and even determine the precise geographic coordinates of every bird on the water.

A large, mixed-species flock of surf scoters, white-winged scoters, scaup, and gulls near a herring spawn event. Herring spawns provide important nutritional resources for a variety of marine bird and waterfowl species, particularly during spring migration. WDFW photo.

This image demonstrates the results of the machine learning processes. First, a model detects birds in the photo and places colored boxes around each individual. The technology is then able to identify the species of each bird. Sexually dimorphic species, such as waterfowl, are also identified by sex. Different box colors indicate various species and sexes of birds found in the image. In this example, male scaup are marked with red boxes and male white-winged scoters are marked with blue boxes. Photos by WDFW.

What the data reveals

The information gathered during these midwinter surveys feeds directly into WDFW’s Seabird Survey Web Map, a public tool that allows researchers, planners, and policy makers to explore bird abundance by species, year, basin, and water depth.

The data helps answer critical questions:

• Where are seabirds most concentrated and why?
• How are populations changing over time?
• How do development, climate, and human activity affect marine ecosystems?

These insights guide decisions around wildlife management and harvest regulations, oil spill response planning, coastal and marine permitting, habitat protection and restoration efforts, and long-term ecosystem monitoring.

A mixed-species flock of common and red-breasted mergansers. Machine learning processes can readily identify and distinguish adult males of similar species, such as common and red-breasted mergansers, common and Barrow’s goldeneye, and surf and white-winged scoters. WDFW photo.

The Midwinter Aerial Seabird Survey surveys help ensure that decisions affecting Washington’s waterways are grounded in real, observed conditions. As technology continues to evolve, so too will the ways biologists monitor and protect marine ecosystems.

Learn more about WDFW’s seabird monitoring on our website.

This article was adapted from a blog originally published by Kenmore Air. Read the full piece on Kenmore Air’s website.