Long-tailed Duck

(Clangula hyemalis)

General Information:  Formerly known as Old Squaw, this duck is a circumpolar breeder and a common winter resident in Kachemak Bay off the Homer Spit.  The “old squaw” name was in reference to the bird’s talkative behavior, although it is the male Long-tailed Duck that “talks” the most. 

The Long-tailed Duck  is a member of the Anatidae family, and the only living member of the genus Clangula. 

Range:  You will have to travel north to find these birds – summer or winter.    In North America they winter in the northern portions of the eastern U.S., Alaska, and Canada, and breed in the Alaska, northern Canada, and the Soviet Union. 

Source: https://www.allaboutbirds.org/guide/Long-tailed_Duck/maps-range

Worldwide Range

Source: http://maps.iucnredlist.org/map.html?id=22680427

Bird Biology:

Characteristics/Description:   The summer breeding plumage is distinctively different from the winter plumage.  In summer, males have a black head, chest, and wings with a gray face patch that surrounds the eyes.  The male’s upper back feathers are long and buffy with black centers.  The central tail feather very long (hence their name).   The male’s winter plumage, displays a white head and neck, but the gray face patch remains.  The winter plumage also includes large black spots extending from the side of the check down through the side of the neck.  There is a black band across the breast and lower neck.  Their lower back is black.  The upper back feathers are long and gray.  The central tail feather is black.  Eyes are a dull yellow-brown. 

Females in the summer have mostly a dark head and heck, with a white patch around the eyes, extending in a thin line towards the ears.  Back and breast are various shades of gray or brown.  Eyes are brown.  During the winter, their head and neck are white with a round dark brown cheek patch.  They have a white belly.  Their crown, breast, and back are brownish-gray.

Both sexes have uniformly dark under-wings, and small bodies with large heads.  They sit low in the water and are often hidden by the ocean waves. 

Preferred Habitat:  During the breeding season, lakes and ponds are preferred.  During the winter, they prefer the open ocean and can also be found on large freshwater lakes.  A good spot to find them in Kachemak Bay is off the end of the Homer Spit.

Breeding Season:  Breeds in the northern Arctic boreal forest and tundra, utilizing open permafrost pools and lake islands.  The breeding season begins in late May in the south, to June in the north.  They have a single brood. 

Nest:  The nest is a shallow scrape on the ground (often islands or peninsulas), lined with nearby plant material (e.g., willow and/or birch leaves), down, and feathers.  The nests are placed close to the water.  These birds are sociable nesters, nesting near other Long-tailed Ducks. 

Eggs and Incubation:  Usually 5-9 eggs constitute a clutch.  The female incubates the eggs for 23-25 days.  The chicks are born precocial (eyes open) and downy.  The young are lead to sea shortly after hatching.  They are able to swim, dive, and feed themselves immediately. 

Fledging: The hatchlings become independent approximately 5 weeks after hatching. 

Food Preferences:  Long-tailed ducks eat aquatic invertebrates – crustaceans (e.g., amphipods and cladocerans), mollusks, fish, and other marine invertebrates.  During the breeding season, they will also eat freshwater insects and insect larvae, plant material (algae, grasses, seeds, and fruits of tundra plants). 

Feeding Methodology:  Long-tailed ducks are “diving” ducks. 

Migration:  The Long-tailed Duck migrates from its breeding ground in the far north to its wintering grounds in the not so far north.  Spring migration to the breeding grounds begins late February through May, and fall migration to the wintering grounds begins in October continuing through December.   The migration is often in groups, and the birds fly low over the water. 

Vocalizations:  These birds are active vocalizers all year long.  Their call is a three-part yodel. 

Threats:  These birds are “sea” birds and are susceptible to by-catch in gill nets, and oil pollution.

Fun Facts:

• This bird can dive 200 feet, although most food is obtained within the first 30 feet of the surface. One of the deepest diving ducks in the world. 
• A diving duck, it spends more time underwater than it does on top of the water.
  
• Adults molt three times per year, rather than the typical two times per year of other ducks.
• And that beautiful plumage we see during the winter? That is actually their breeding plumage (attracting a mate), although the birds actual breed during the spring where their plumage is non-breeding plumage.  Confusing right?

Conservation Status:  The world population is estimated at between 3.2 million and 3.75 million birds. 

The International Union of Concerned Scientists list the Long-tailed Duck as vulnerable due to the severe wintering population decline in the Baltic Sea between the early 1990s and late 2000.

The Alaska Audubon Society has identified the Long-tailed Duck as a species in possible decline on the Yukon-Kuskokwim Delta, although stable on the Alaska Coastal Plain (Audubon Alaska Watchlist 2017:  Common Species Suspected to be Declining). 

Similar Species:  Harlequin Duck, Northern Pintail, Steller’s Eider.

Sources of Information:

All About Birds.  2017.  Cornell Lab of Ornithology.  Downloaded on 29 July 2018.  https://www.allaboutbirds.org/guide/Long-tailed_Duck/id

Audubon: Guide to North American Birds.  Downloaded on 30 July 2018 at https://www.audubon.org/field-guide/bird/long-tailed-duck. 

Baicich, Paul J. and Colin J.O. Harrison.  19997.  Nests, Eggs, and Nestlings of North American Birds, 2nd Edition.  Princeton Field Guides. 

BirdLife International. 2018. Clangula hyemalis (amended version of 2017 assessment). The IUCN Red List of Threatened Species 2018: e.T22680427A122303234. Downloaded on 29 July 2018.

Dunn, Jon L. and Jonathan Alderer, Editors.  National Geographic: Field Guide to Birds of North America.  5^th Edition, 2^nd Printing.  2008.

Dunne, Pete.  2006.  Pete Dunne’s Essential Field Guide Companion:  Comprehensive Resource for Identifying North American Birds.  Houghton Mifflin Company. 

Henri Ouellet//Macaulay Library at the Cornell Lab (ML Audio 74469)

Warnock, N. 2017. The Alaska WatchList 2017. Audubon Alaska, Anchorage, AK 99501.

American Dipper

(Cinclus mexicanus)

Photo by Michelle Michaud

General Information:  As the name implies, the American dipper (Cinclus mexicanus), also formerly known as the “Water Ouzel”, is characterized by its dipping movements.  The American dipper is a stocky dark grey bird with a head sometimes tinged brown and distinctive white feathers on the eyelids that cause the eyes to flash white as the bird blinks.  It has long legs, and bobs its whole body up and down while perched on a rock in or near a stream.

The American Dipper’s habit of ‘dipping’ or bobbing up and down while perched on a rock or ledge is not well understood though some believe the action of dipping may help them spot prey beneath the surface of the water or help conceal their image from predators.  Dipping may also be a form of visual communication between birds in the noisy environment they favor – clear, clean, fast-moving streams.

The American dipper is of the Order, PASSERIFORMES; Family, Dipper (Cinclidae).

Range:  The American Dipper is ‘Alaska Hardy’ — a permanent resident of the Kenai Peninsula, but also able to tolerate winters even in the Brooks Range and Seward Peninsula.  Now that’s cold. 

The American Dipper is North America’s only aquatic songbird, and one of five species of dipper in the world (Europe, Northern Africa, Asia, South America, and North America).

Range Map Source:  https://www.allaboutbirds.org/guide/American_Dipper/maps-range

Bird Biology:

Characteristics:  It is hard to mistake the American Dipper with its dependency on streams and its iconic bobbing nature.  Look for a bird 5.5 to 7.9 in (14 to 20 cm) in length, and weighing in at 1.5 to 2.4 oz. (43 to 67 g).  Males and females look alike, although the average body mass of males is slightly greater than females.  Unlike most other songbirds, but similar to ducks, the American Dipper molts its wing and tail feathers all at once in the late summer. The bird is flightless during this time.

Find a fast-moving stream, look for a stream boulder, and the probability of seeing a dipper increase as they will spend up to 10 minutes preening (preen oil glands), creating their form of wet suit – necessary for waterproofing and insulation.

The American Dipper takes a ‘polar dip’ in the cold water with relish. It is well-adapted to its cold, underwater habitat. The American Dipper has a thick coating of down and feathers as insulation, large preen glands secreting oil to waterproof their feathers, a moveable flap over the nostrils that seals when the bird is underwater, blood cells with a large capacity for carrying oxygen, and an efficient internal system of thermoregulation.

Preferred Habitat:  American Dippers are stream-dependent, foraging in clear fast-moving streams with rocky bottoms.  They prefer unpolluted waters, and can be found in mountain, coastal, or even desert streams.

Breeding:  Dippers are fiercely territorial, vigorously defending their linear stream-dependent nesting territory from other pairs. They are mainly monogamous and in most cases return to the same nest year after year. The American Dipper breeds along swift, rocky streams, seeming to favor clear, cold water, often in narrow canyons. Seem repetitive…Guess you have the picture now about stream preference.

The courtship display may have either the male or female strutting and singing in front of the other bird, with wings drooping and bill pointed up.  The pair may then conduct a ‘flight chase’ with complex aerial maneuvers, all the while singing.  Though some pairs stay together in winter, the dipper is generally a solitary bird; after the chicks’ fledge, parents often divide their brood and their territory and part ways.

Nesting:  The nest, probably built by the female, is a volleyball-sized shell of moss, with an inner saucer of dry grass on which 4-5 white eggs are laid. In Alaska, nest building usually begins in April or May, though cold weather and high altitudes may result in delayed nesting.

Nest sites include a slight ledge on a mossy rock wall just above stream, among roots on a dirt bank, or behind a waterfall.  The nest is often placed where it remains continuously wet from flying spray.  Many dippers commonly select nest sites under bridges – an adaptable bird.  Good nest sites seem to be the main limiting factor for the presence of a population of dippers.  So if you see a bridge near a fast moving stream and you can look under the bridge, check for a dipper nest.

The clutch is incubated for 2 to 2.5 weeks. Females do all the incubation, but males bring food to the incubating female. The female will brood the chicks for a week or more while the chicks grow feathers to help regulate their body temperature. Both parents feed the chicks, bringing insects and small fish – feeding the hungry brood as many as 20 times an hour.  One would think the parents would be worn out after all that activity, but second broods have been recorded.

Fledging:  When born, the chicks are helpless with sparse down, but are ready to leave the nest in about 24-25 days.  The young are fed by both parents for another two weeks after fledging, as they gradually learn how to find and catch their own prey.  Chicks are able to swim and dive after fledging.

Food Preferences:  The American Dipper feeds on aquatic insects and their larvae (yay! mosquitoes) and may also eat fish eggs and very small fish (less than 3″ long).

Feeding Methodology:   The American Dipper can wade, swim, and dive from either the water or the air and are capable of moving underwater rocks on the stream bed to get food.

Photos by Michelle Michaud

The American Dipper uses its short, stubby wings to ‘fly’ underwater with powerful strokes of their partially folded wings when chasing prey.  They can take prey from the water’s surface while swimming or from mid-air while in flight, but most food is taken underwater.

With its long legs and strong toes, the American Dipper is an underwater marvel; easily able to negotiate along the bottom of fast-moving, rocky streams in current capable of knocking over you or I.

Roosting:  A variety of sites on the ground adjacent to streams are used for nocturnal roosts.

Migration:  The American Dipper is not a long-distant migrant so it is a ‘Homer Bird’ — a  permanent resident of the Kenai Peninsula; but it may move to other locations if necessary to find food or unfrozen water.

Vocalizations:  The song consists of high whistles or trills peee peee pijur pijur repeated a few times.  The song has also been described as a loud, bubbling song.  Whatever you interpret, you will hear the dipper as the song carries over the noise of stream rapids.   Both sexes of this bird sing year round, but are often quiet after nesting.

Call:  The call is a harsh, zeet-zeet-zeet.

Fun Facts:

• Eat and be eaten… The American Dipper eats fish eggs, but its habit of diving underwater in search of food can infrequently make it the prey of large salmonids.
• To see an American Dipper stay close to a stream as the dipper will be seen bobbing up and down on a rock in mid-stream, or flying low over the water, following the winding course of a stream rather than taking overland shortcuts.
• The American Dipper is equipped with an extra eyelid called a nictitating membrane allowing it to see underwater.

Conservation Status:  American Dipper presence/absence can be an indicator of stream quality, as aquatic prey becomes scarce in polluted streams.  No food, no dippers.  The dipper has vanished from some locations due to pollution or increased silt load in streams. Also, sedimentation, acidification, and toxic waste from industry of various types can cause dipper reproductive failure and abandonment of a stream.

The American Dipper’s population status is thought to be a species of ‘Least Concern’ by the International Union of Conservation of Nature and Natural Resources, with a stable population.  The American Dipper does not appear on the Alaska Audubon Watchlist (2017).

Other Dipper Species in Alaska: The American Dipper is the only dipper species in Alaska; well okay in all of North America.

Sources of Information:

All About Birds.  Cornell Lab of Ornithology.  Downloaded on 23 November 2018 at: https://www.allaboutbirds.org/guide/American_Dipper/id

Alaska Department of Fish & Game.  Species Profile:  American Dipper.  Downloaded on 23 November 2018 at http://www.adfg.alaska.gov/index.cfm?adfg=americandipper.main

Audubon: Guide to North America Birds. National Audubon Society.  Downloaded on 23 November 2018 at: https://www.audubon.org/field-guide/bird/american-dipper.

Baicich, Paul J. and Harrison, Colin J.O. 1997.  Nests, Eggs, and Nestlings of North American Birds, 2^nd Edition. Princeton Field Guides.

BirdLife International. 2016. Cinclus mexicanus. The IUCN Red List of Threatened Species 2016: e.T22708163A94152063. http://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T22708163A94152063.en. Downloaded on 25 August 2018.

Dunne, Pete.  2006.  Pete Dunne’s Essential Field Guide Companion:  Comprehensive Resource for Identifying North American Birds.  Houghton Mifflin Company.

Randolph S. Little//Macaulay Library at the Cornell Lab

Warnock, N. 2017. The Alaska WatchList 2017. Audubon Alaska, Anchorage, AK 99501.

William W. H. Gunn//Macaulay Library at the Cornell Lab

It’s A Great Day to Bird

 

Common Redpoll

(Carduelis flammea)

General Information:  Common Redpolls are common Arctic and sub-Arctic breeders.  Their numbers vary from year to year (irruptions) depending upon on the availability of seed. 

Description:  These small songbirds are members of the finch family and are about 5.25 inches in length.  Females have a red or orange cap, while males have a red cap and red on the breast and sides, with distinctive black chins.  The male and female have streaking of the flanks, rump, and undertail coverts and a yellow bill. 

North American Range:

 

Source: https://www.allaboutbirds.org/guide/Common_Redpoll/maps-range

Bird Biology:

Preferred Habitat: In winter, the Common Redpoll prefers open woodlands, brushy edges, weedy fields, and is a regular visitor at bird feeders.  During the summer they can be found breeding in varying habitat types: edges of spruce forests, birch stands, mixed conifer and birch, willow thickets, and low tundra shrub.  They avoid dense forest. 

Breeding Season:  Breeding begins in late April in the western states, and June in the east.  The female searches for the nest site and builds the nest on a horizontal branch or in the crotch of a spruce, alder, or willow.  They nest low to the ground.  On the tundra the nest is placed under a rock ledge, in low ground cover, or among driftwood.  

Nest: The nest is cup-shaped, consisting of fine twigs, grasses, and plant stems, and lined with down, feathers, and hair.  In the arctic, old nests may be reused, in which case the female relines the nest.  Pairs will often nest near one another in loose associations.

Eggs and Incubation: Usually 4-5 eggs.  Nestlings are altricial (young are unable to care for themselves when born).  Female incubates the eggs 10-13 days.  Young are tended by both parents. The adult pair remain together and may have from 1-3 broods in a season.  That’s a lot of young ones to take care of each year.

Fledging: The young quickly grow flight feathers and fledge 11-14 days after birth. 

Food Preferences:  Common Redpolls are seed eaters, preferring a seed about the size of their bill.  Birch catkins are a preferred seed source. 

Redpolls do come to feeders, preferring nyjer or thistle seed, but also eating black oil sunflower seed.  They will also scavenge opened seeds left by other birds.

Feeding Methodology:  The Common Redpoll is an active communal forager generally found in flocks. 

Migration:   During a normal year, fall migration begins in late August and extends to early December.  Spring migration is from late February to early June.   Birds migrate during the day and in flocks. 

The Common Redpoll is an irruptive migrant.  They will move south irregularly in winter following patterns in food supply.  Their winter habitat is the northern boreal forest, however every couple of years, redpolls move farther south in winter, occasionally reaching the central or southern United States. Their movements generally correspond to the availability of seeds and population response to increasing numbers.

Vocalizations:

• Song:  Combination of a trill and twittering.
• Call:  Swee-ee-et
• Flight Call:  A dry rattle

Threats:  Climate change is transforming the Common Redpoll habitat.

Fun Facts:

• During a winter night, the Common Redpoll will tunnel into the snow to stay warm. These tunnels may be more than a 12 inches long and 4 inches under the snow.  Brrrr.
  
• The Common Redpoll can pull a string to get to a piece of hanging food. They can shake seeds out birch catkins so the seed falls to the ground where the birds easily eat them.
• Redpolls have throat pouches where they temporarily store seeds to later take to a protected, warm spot to eat.
• Some redpolls eat a diet consisting entirely of birch seeds.
• Redpolls have high-energy needs and can eat up to 42% of their body mass each day.
• Redpolls are ‘Alaska Hardy’ and have been found to survive in areas where the temperature dips to minus 65 degrees F. That’s cold!!!
• A redpoll banded in Alaska was recovered in the eastern U.S. A redpoll banded in Belgium was found in China two years later.  Those are long distance trips. 

Conservation Status:  Common Redpolls are species of least concern, but populations are declining. Their estimated global population is 160 million.

Similar Species in Alaska:  Hoary Redpoll

Sources of Information:

All About Birds.  2017.  Cornell Lab of Ornithology.  Downloaded on 5 June 2018, and 19 July 2018.  https://www.allaboutbirds.org/guide/Common_Redpoll/id

Arthur A. Allen//Macaulay Library at the Cornell Lab

Baicich, Paul J. and Harrison, Colin J.O. 1997.  Nests, Eggs, and Nestlings of North American Birds, 2^nd Edition. Princeton Field Guides.

Dunn, Jon L. and Adlerfer, Jonathan, Editors.  National Geographic: Field Guide to Birds of North America.  Fifth Edition.  2006. 

Dunne, Pete.  2006.  Pete Dunne’s Essential Field Guide Companion:  Comprehensive Resource for Identifying North American Birds.  Houghton Mifflin Company. 

Geoffrey A. Keller//Macaulay Library at the Cornell Lab

National Audubon Society.  Birds of North America.  Downloaded on 19 July 2018.  https://www.audubon.org/field-guide/bird/common-redpoll

Sibley, David Allen.  2003.  The Sibley Field Guide to Birds of Western North America.  Andrew Stewart Publishing Inc. 

The IUCN Red List of Threatened Species. Version 2018-1. <www.iucnredlist.org>. Downloaded on 19 July 2018.

Warnock, N. 2017. The Alaska WatchList 2017. Audubon Alaska, Anchorage, AK 99501.

 It’s A Great Day to Bird

 

Northern Saw-whet Owl

(Aegolius acadicus)

General Information:  The Northern Saw-whet Owl is a small owl about the size of an American Robin.  They are members of the Strigidae family.

North American Range

Source: https://www.allaboutbirds.org/guide/Northern_Saw-whet_Owl/maps-range

Bird Biology:

Characteristics/Description: Northern Saw-whet Owl is a charismatic small owl – 7.1 to 8.3 inches in height, with a wing span between 16.5 and 18.9 inches – an owl that will fit in the palm of your hand.  Adults are mottled brown with a whitish facial disk and white-spotted head.  Their beak is black and their eyes are yellow.  Juveniles are dark brown with a cinnamon-colored breast and belly.  They have large, rounded heads that lack ear tufts. 

Preferred Habitat: You’ll only find these owls in the forest, preferring mature forests with an open understory (for foraging).  They prefer deciduous trees for nesting and dense conifers for roosting (the better to hide), with riverside habitat nearby. 

Breeding Season:  Breeding season begins mid-March to mid-April, ending in late June.  They are generally monogamous, however, if there is sufficient food available the male will mate with more than one female.  Males begin calling (incessantly) in late January to attract a mate and to defend its territory. 

Nest:  The females choose the nesting location.  They are secondary cavity nesters (nesting in previously excavated holes – think woodpecker hole) in dead snags.  They are not known to reuse a nest cavity two years in a row. 

The nest is located at the bottom of the cavity, and may consist of wood chips, twigs, moss, hair, and small mammal bones or may even be unlined.   Nest cavities may be anywhere from 8-60 feet off the ground.  The nest hole is generally 3inches wide and 9-18 inches deep. 

Northern Saw-whet Owls also will use nest boxes (see https://nestwatch.org/learn/all-about-birdhouses/birds/northern-saw-whet-owl/ for plans on how to build a nest box).  You might want to consider one for your home, provided you have the right habitat.  If you install a nest box it is helpful to lay some wood chips in the bottom.

Eggs and Incubation:  The female Northern Saw-whet Owl lays between 4-7 eggs (generally 5-6) with a 1 to 3-day interval between each egg, and can have up to two broods per year.  The eggs are incubated by the female for 26-29 days.  The young hatch in intervals, and are taken care of by the female, although the male brings food to the nest during incubation and brooding.  The chicks fledge within three-weeks of hatching at which time the female and male hunt and feed the young. The young are born covered in white down, eyes closed (opening 8-9 days later).  They are semi-helpless when born. 

Fledging:  The young leave the nest 27-35 days after hatching.  However, they remain near the nest and are feed (primarily by the male) for another four weeks or more. 

Food Preferences:  So what do these birds like to eat?  The mostly eat small mammals – mice, shrews, voles, shrew-moles, bats, and the young of chipmunks, squirrels, and gophers. 

All food bets are off during migration, where they supplement their diet with birds – chickadees, juncos, sparrows, wrens, warblers, robins, waxwings, and kinglets.  They may also eat insects such as grasshoppers, moths, beetles, and bugs.i

In the Homer area (coastal), they may also eat intertidal invertebrates, such as amphipods and isopods. 

Feeding Methodology:   These owls hunt at night (nocturnal), using both sight and sound; hunting hunt from a low perch along the forest edge flying silently and low towards prey. 

Roosting:  These birds roost during the daytime in dense vegetation making them difficult to see even though they are typically just above eye level.   

Migration:  The Northern Saw-whet Owl is both a resident and a long-distance migrant.  They may migrate north/south or in altitude (moving to lower elevations in the winter).  Others may remain in the same location year-round.  These birds migrate at night using known migration routes across the continent.  They are found year-round in Alaska, although their range is quite limited (see range map). 

This owl winters in a variety of woodland habitats, but may also be found in suburban and urban areas.   Spring migration begins late February and continues into May.  Fall migration is from late September to December, peaking in October and early November.

Vocalizations:

Call:  A rhythmic, repetitive toot, toot.

The bird is most vocal before dawn.  During the breeding season the male gives this rhythmic song for hours without a break.

Threats:   Habitat loss due to reduction in mature forests through logging.  Climate change. 

Fun Facts:

• Kachemak Bay Birder Jason Sodergren of Homer Alaska has been banding Northern Saw-whet Owls at his home since 2009. To date, he has captured and banded 1231 of these cute, little owls – many of them juveniles.  That is a lot of owls coming through the Homer area. 
• Its name may have come from its call, which has been likened to a saw being sharpened on a whetting stone. 
• Migrating Northern Saw-whet Owls can cross large bodies of water, e.g. the Great Lakes.
• The female keeps a very clean nest, however, once she leaves to roost elsewhere (and prior to the young fledging), the young birds can quickly turn that clean nest box into a typical youngsters’ quarters – messy (layers of feces, pellets, and rotting prey parts).

Conservation Status:  The Northern Saw-whet Owl is a common species, with an estimated global breeding population around 2.0 million.

Only the Southern Appalachian Northern Saw-whet Owl population is listed on the Audubon 2014 State of the Birds Watch List.  This population is at risk of becoming threatened or endangered unless conservation actions are undertaken.  South Dakota and North Carolina have listed the birds as species of special concern.

The International Union of Concerned Scientists listed the Northern Saw-whet Owl as a species of least concern, with a declining population trend.

The species is not listed on Alaska Audubon’s Alaska WatchList 2017. 

Similar Species in Alaska:  Boreal Owl, Northern Hawk Owl

Sources of Information:

All About Birds.  2017.  Cornell Lab of Ornithology.   Downloaded on 3 August 2018 at: https://www.allaboutbirds.org/guide/Northern_Saw-whet_Owl/id

Audubon:  Guide to North America Birds.  Downloaded on 6 August 2018 at: https://www.audubon.org/field-guide/bird/northern-saw-whet-owl

Baicich, Paul J. and Harrison, Colin J.O. 1997.  Nests, Eggs, and Nestlings of North American Birds, 2^nd Edition. Princeton Field Guides.

BirdLife International. 2016. Aegolius acadicus. The IUCN Red List of Threatened Species 2016: e.T22689366A93228694. http://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T22689366A93228694.en. Downloaded on 06 August 2018.

Dunne, Pete.  2006.  Pete Dunne’s Essential Field Guide Companion:  Comprehensive Resource for Identifying North American Birds.  Houghton Mifflin Company. 

Warnock, N. 2017. The Alaska WatchList 2017. Audubon Alaska, Anchorage, AK 99501.  Downloaded on 6 August 2018 at: http://ak.audubon.org/conservation/alaska-watchlist

It’s a Great Day to Bird