The Puget Sound, located in the Pacific Northwest region of North America, is home to a diverse array of marine birds. Of the many species that inhabit the inland waters, estuaries, and shorelines of the Puget Sound, some are particularly well-adapted for diving and foraging in the area’s rich waters.
The Common Loon
One of the most recognizable diving birds found in the Puget Sound is the common loon (Gavia immer). Also known as the great northern diver, this large bird measures 70–90 cm (28–35 in) in length with a wingspan of 130–170 cm (51–67 in). Its plumage is checkered black-and-white during the breeding season and gray in winter. The common loon is well-suited to diving and swimming underwater. Its heavy, streamlined body allows it to sink easily, while its strong legs placed far back on its body propel it through the water when submerged. Its pointed bill is perfect for catching slippery fish.
Common loons spend most of their time in water, only coming ashore to mate and incubate eggs. They nest along quiet inland lakes, rivers, and sheltered bays, breeding in summer months and migrating south in winter. Though they struggle on land due to their rear-placed legs, these birds are graceful and agile in water. Common loons make eerie, wailing calls that echo across lakes and bays. They feed mainly on fish such as herring, carp, and perch, but also eat aquatic invertebrates, frogs, and aquatic plants.
Breeding and Nesting
Common loons return each spring to breed in the clear, quiet lakes of the Puget Sound region. Courting pairs perform elaborate mating rituals, including the “penguin dance” where they rush across water surface while spraying each other with water. Between April and May, the female lays 2 eggs which both parents incubate for 28-30 days. Loon chicks are precocial, able to swim and dive right after hatching while carried on their parents’ backs. Parents fiercely defend territory and chicks from predators and other dangers. Many Puget Sound lakes host breeding pairs of common loons each summer.
Threats and Conservation
Though common loon numbers are healthy overall, they face threats in the Puget Sound area. Shoreline development, recreational pressures, and environmental contaminants impact their breeding habitat. Loons are sensitive to human disturbance and may abandon nests when feeling threatened. Conservation efforts focus on protecting important nesting lakes as wildlife reserves and limiting shoreline development and recreation during breeding months. With appropriate habitat conservation, the iconic common loon will continue diving and fishing in the Puget Sound’s waters for years to come.
The Western Grebe
Another diving bird well-adapted to the Puget Sound’s habitats is the western grebe (Aechmophorus occidentalis). This large waterbird measures 46–56 cm (18–22 in) with a 71–86 cm (28–34 in) wingspan. It has a long, slender neck and a pointed bill perfect for spearing fish. Its black crown and hindneck contrast with its bright red eyes. Western grebes nest in colonies along shallow, vegetated lakes and wetlands. They feed mainly on small fish and aquatic invertebrates.
Diving Adaptations
The western grebe’s streamlined body and lobed feet make it perfectly suited to diving and swimming underwater. Its feet are placed far back on its body, providing excellent propulsion. Flat bones and dense plumage help reduce buoyancy, allowing the bird to sink easily. Since its wings are small relative to its body size, the western grebe cannot take flight from water. Instead, it must run across the water while flapping to become airborne, in a spectacle known as “dancing” or “rushing”. This running start gives it the momentum and lift needed for flight.
Breeding Rituals
Western grebes perform elaborate mating displays, unique among North American waterbirds. They engage in “rushing” across the water surface, as well as synchronous head shaking and diving, all while swimming together. Western grebes nest in large colonies, building floating nests anchored to emergent vegetation in shallow water. Parents share incubation duties. Newly hatched chicks ride on their parents’ backs until they fledge at 10-12 weeks. Though western grebe numbers are currently stable, habitat loss threatens some breeding colonies in the Puget Sound region.
The Surf Scoter
The surf scoter (Melanitta perspicillata) is a large sea duck found year-round in the Puget Sound and along the Pacific coast. It is a premier diving duck, foraging for food in deeper waters near rocky coasts, inland lakes, and estuaries. Adult males are unmistakable with their black plumage, bold white patches on the forehead and nape, and large orange-and-black bill. Females are brownish-gray with a small whitish patch behind the bill.
Diving and Feeding
With their robust bodies, large feet set far back for propulsion, and thick plumage that traps air for insulation and buoyancy, surf scoters are well-adapted to diving deep underwater. Their short wings provide power for swimming as they hunt for prey near the sandy or muddy bottom. Using their specialized bills, surf scoters feed mainly on mollusks, crustaceans, and other small invertebrates. The large-gaped bill allows them to extract prey from shells very efficiently.
Breeding and Migration
Surf scoters breed in the northern boreal forests and subarctic regions of North America. They migrate south along the Pacific coast for the winter. The Puget Sound provides prime overwintering habitat for surf scoters, with its abundance of mussels, clams, crabs, and other prey. Surf scoters form large flocks and dive together, feeding cooperatively. Conservation efforts focus on protecting marine habitats from pollution and overdevelopment for the benefit of overwintering waterfowl.
Rhinoceros Auklet
An unusual-looking seabird well-suited to diving in the Puget Sound is the rhinoceros auklet (Cerorhinca monocerata). This chunky, dark-gray bird measures 25–30 cm (9.8–11.8 in) long with a 49–58 cm (19–23 in) wingspan. As its name suggests, it has a horn-like extension on its orange bill used for courtship displays. The rhinoceros auklet nests in burrows on small offshore islands and feeds on small fish, krill, and plankton across the Puget Sound and northern Pacific.
Diving Adaptations
The rhinoceros auklet has several adaptations that aid its diving ability. Its wings provide power for “flying” underwater as it swims. Its feet are webbed for surface swimming and placed far back on its body to propel dives. Dense plumage and solid bones provide weight for descending rapidly into water. Like other alcids, rhinoceros auklets close their nostrils as they dive, preventing water entry.
Breeding and Conservation
Rhinoceros auklets nest in burrows on islands in the Puget Sound, using their distinctive bills in courtship displays. Parents take turns incubating the single large egg. The chick fledges at night, swimming away from land under the cover of darkness. Major threats include invasive species, habitat loss, pollution, and human disturbance. Conservation efforts across the Puget Sound protect seabird colonies and restore nesting islands.
Marbled Murrelet
An unusual small seabird that thrives diving for fish in Puget Sound waters is the marbled murrelet (Brachyramphus marmoratus). Despite being classified as a seabird, this robin-sized bird actually nests inland up to 50 miles from shore in old-growth and mature forests. It is uniquely adapted to fly from its forest nest to coastal feeding grounds multiple times per day.
Diving Adaptations
The marbled murrelet excels at diving and swimming using its compact, streamlined body shape and relatively long, narrow wings. Its feet are placed far back on its body and webbed for propulsion underwater. By flapping its wings up to 200 times per minute, the murrelet can dive to depths of over 100 feet in pursuit of small fish and invertebrates.
Breeding and Conservation Challenges
The marbled murrelet’s dependence on both old-growth forests for nesting and coastal marine areas for feeding makes it highly vulnerable to habitat loss in the Puget Sound region. Extensive logging of coastal old-growth forest is linked to population declines over the past century. Conservation efforts aim to protect remaining nesting habitat and restore degraded forest land for future recovery of this species.
Cormorants
The Puget Sound is home to a number of cormorant species, waterbirds perfectly adapted for diving and swimming in pursuit of fish. These seabirds have long necks, slender hooked bills, and cruciform tails. Their wings have reduced feathering to decrease buoyancy underwater. Two species commonly seen around the Puget Sound are the double-crested cormorant (Phalacrocorax auritus) and the pelagic cormorant (P. pelagicus).
Diving Adaptations
Cormorants are expert divers, capable of plummeting deep below the water’s surface and swimming in pursuit of fish with great speed and agility. Their feet have all four toes joined by webbing, providing excellent propulsion. They are able to dive to depths of over 45 meters (150 feet). Since their plumage absorbs water, cormorants must stand with wings outstretched to dry after fishing.
Breeding and Threats
Cormorants nest colonially along rocky shorelines and on islands throughout the Puget Sound, building nests of sticks, vegetation, and guano. Double-crested cormorants suffered severe declines due to DDT and other pesticide use but rebounded after the chemicals were banned. Ongoing threats include human disturbance, predation, and contamination from oil spills and other pollutants. Protection of nesting sites and reduction of contaminants are vital for cormorant conservation.
Pigeon Guillemot
The pigeon guillemot (Cepphus columba) is a small alcid perfectly adapted to pursue fish and invertebrates while diving and swimming in Puget Sound waters. This sooty-gray seabird has bright red feet and mouth lining, and white wing patches that flash in flight and underwater. It nests along rocky coasts and feeds near shore, rarely venturing onto land except for breeding.
Diving Adaptations
The pigeon guillemot’s compact, teardrop-shaped body and long, pointed wings make it streamlined for diving in open water after prey. Its feet are placed far back on its body and fully webbed for swimming and launching dives. It propels through water with its wings and can dive to depths of over 30 meters (100 feet). Like other alcids, it closes its nostrils when diving to prevent water entry.
Breeding and Conservation
Pigeon guillemots nest in cavities along rocky shorelines, defending nesting territories from predators with loud whistling calls. Both parents incubate the eggs and feed the chicks. Major threats come from oil spills, overfishing of prey species, and human disturbance of breeding colonies. Protecting nesting sites and restricting development are key conservation aims for this and other seabirds.
Conclusion
The Puget Sound provides prime habitat for a diverse array of diving birds due to its coastal fjords, estuaries, rocky shorelines, and abundant marine life. From the common loon patrolling a secluded lake to the marbled murrelet commuting inland to its old-growth nest, the birds that dive and swim in these rich waters are specially adapted to find food and breed along the region’s intersecting marine and terrestrial ecosystems. Protecting the health of Puget Sound habitats will ensure these remarkable birds continue gracing the region’s landscapes and waterways.