Birds of a Feather

What do you imagine when you hear the word “feather”?

It’s likely that you imagine a tail or wing feather. But did you know there are 6 major types of feathers on a bird’s body? Each of the major types has specific form and function.

Let’s start by defining two important terms in regards to feather structure. A feather is either pennaceous or plumulaceous. Pennaceous feathers are what most people imagine to be a “typical” feather. Pennaceous feathers are flexible and consist of the following parts:

  • Vane-  the flat surface of a pennaceous feather
  • Barbs- hundreds of stiff filaments that attach to a rachis
  • Rachis- a relatively solid structure that extends down the middle of the feather
  • Ramis- a central shaft which has slender branches on either side
  • Barbules- the slender branches on either side of the ramis.
  • Barbicels- tiny hooklets that attach the barbules together and create the flatness of the vane
askabiologist.asu_.edu_
Anatomy of a feather (Image via Birdtricks.com)

Plumulaceous feathers have barbs that are loose and fluffy. Their barbs have rami that are less stiff and the barbules are usually either reduced or thinner. As a result, plumulaceous feathers cannot hold anything except a delicate, rounded form. When you see a chick with down, you are seeing an example of plumulaceous feathers.

Feathers grow out of and remain attached to a feather follicle in the epidermis. If you’ve ever seen the bumps on a plucked chicken, then you have seen feather follicles.

Now that we’ve discussed the basics of feather structure, let’s examine the 6 major feather types.

cornell
Major Feather Types (Image via Bird Academy/Cornell Lab of Ornithology)

1. Down Feathers

These feathers are entirely plumulaceous, making them soft and fluffy. Down feathers act as insulators that allow birds to manage their internal body temperatures by thermoregulation. There are 3 types of down feathers.

  • Natal Down temporarily covers the entirety of a hatchling’s body. Birds that are precocial (able to feed/tend to itself immediately after hatching, therefore not relying on a parent) tend to have more natal down since they have to maintain their temperatures on their own. Altricial birds (who rely on a brooding parent) have sparse natal down since they receive heat transferred by a parent.
  • Body Down lies under the contour feathers of many adult birds. These are more common in waterbirds such as penguins, loons, and ducks. Ever see a duck or goose line its nest with feathers? These are body down from their breast.
  • Powder Down are unique because they grown continuously and disintegrate at the tips to produce a keratinous “powder”. They help make feathers waterproof, and are only found in certain kinds of birds, such as pigeons and herons.

2. Contour Feathers

These feathers give a bird their characteristic shape and make up its exterior. The top section of these feathers are pennaceous, while the bottom section is plumulaceous. Many birds can use oil from the uropygial gland at the base of the tail to help their contour feathers repel water. Contour feathers have a variety of functions including aiding in thermoregulation, streamlining the body during flight, and social displays.

IMG_3353
Great Egret showing off its nuptial plumes (Image by BirdNation)

3. Flight Feathers

Flight feathers make up the majority of the tail and wing feathers. They are almost completely pennaceous. The anterior and posterior edges of flight feathers are asymmetrical. The leading edge (a.k.a anterior edge) is typically thinner than the trailing edge (a.k.a posterior edge).  This feature allows flight feathers to stabilize under the pressure of air currents during flight. These feathers are usually the stiffest and largest feathers on a bird. There are 2 types of flight feathers:

  • Remiges originate from the wings and attach to the bone. The feathers of the outer wing are called primaries and the feathers of the inner wing are called secondaries. The number of primary and secondary feathers vary by bird, but typically a bird can have between 9-12 primaries and 8-32 secondaries.
  • Rectrices  form the tail surfaces/airfoil of a bird. The central pair of rectrices attach directly to the tailbone. Like remiges, number of retrcies vary by bird size, but is typically between 6-32.

Coverts are smaller contour feathers that overlap the wing and tail feather and create the streamlined shape that is important to the aerodynamics of flight.

img_1840
The rectrices and remiges of a Bonaparte’s Gull (Image by BirdNation)

4. Semiplumes

Semiplumes are the intermediate form between the contour and down feathers. Their barbs usually lack hooks, so their vanes are not pennaceous. They occur at the edges of contour feather tracts and complement the insulation of down feathers.

5. Bristles

Bristles are highly specialized and lack barbs along most of its length. Their rachis are very stiff and they are almost exclusively found on a bird’s head. The most common type are rictal bristles, which commonly project at the beak’s base. Many birds that are insectivores, like flycatchers, have rictal bristles.

6. Filoplumes

Filoplumes are hair-like feathers and are the smallest of all the feather types. They have a rachis but few or no barbs. They’re usually hidden underneath the contour feathers. Instead of feather muscles, they have sensory receptors in their skin near the follicles. Filoplumes aid birds in detecting changes in feather position caused by body movement or wind.


Feathers are an amazing adaptation that is unique to birds. Knowing the types of feathers helps us appreciate how complex and special birds are.

IMG_4701
Hooded Merganser preening (Image by David Horowitz)

My New Avian Journey

So yesterday, I teased that I would be starting a new bird-related journey soon. Well, without further ado:

IMG_1740

 

I will be taking the Cornell Lab of Ornithology’s Comprehensive course in Bird Biology!

If you’ve been reading my blog for awhile, I’m sure you know that the Cornell Lab of Ornithology is one of my favorite places. It’s one of my main sources of avian information and we even took our 2016 vacation to Ithaca, NY specifically to go birding at the Lab (you can read about that here and here). As a Lab member, I’ve spent countless hours on their website reading articles, watching videos, taking webinars, and watching bird cams.

So when I learned about their Bird Biology class, I knew I had to take it. My dream is to be a Conservation Biologist/Environmental Scientist/Ornithologist, which is why when I’m not at my non-science related full-time job, I’m taking night/summer classes as a biology major. But when I found out about the Lab’s course, I knew it would exactly what I needed to start moving forward with my goals.

The Lab’s Bird Biology course is a university-level self-study course that anyone interesting in birds can take. The course was developed was by one of my favorite ornithologists, Dr. Kevin McGowan, as well as Dr. Sarah Wagner. (Side note: I took a webinar with Kevin McGowan a few winters ago: Odd Ducks and Wandering Waterfowl. If you’re interested in identification courses I recommend checking out his classes/webinars). The course consists of using the textbook (pictured above) and online resources, as well as multiple tests and quizzes for each chapter.

Pretty much anything you would want to know about birds can be found in this course. Topics covered throughout the 700-page book include anatomy, evolution, migration, vocal behavior, social behavior, ecology of populations, and flight to name a few topics. I’m so excited to dive even further into the avian world and share some of the information I learn with you!

If your interesting in learning about the Cornell Lab’s Bird Biology course check out their website.

 

Happy Birthday, John James Audubon!

“I know I am not a scholar, but meantime I am aware that no man living knows better than I do the habits of our birds; no man living has studied them as much as I have done.” 

These are the words of John James Audubon, the great ornithologist, naturalist, and artist. Today, April 26th, is Audubon’s birthday. He was born 232 year ago 1785. Audubon is known for his double-elephant folio prints of The Birds of America, which was a spectacular achievement and contribution to the study of ornithology. In honor of Audubon’s birthday, here are some interesting facts about The Birds of America.

472px-John_James_Audubon_1826
John James Audubon in 1826, portrait by John Syme
  • Audubon’s love for birds and nature stem from his childhood in France. His father encouraged him to study birds and draw. As he grew up, his artistic abilities improved, and he developed a unique way of sketching birds. After shooting the bird, he would pin it up on a grid. At the time, many artists would draw a bird in profile on a plain background. Audubon however, wanted his birds to look like they were moving, so he positioned them so it looked like they were either flying, hunting, or feeding and placed them in elaborate scenes.
  • As a young man, Audubon never considered publishing his illustrations, until he met the famed ornithologist of the time, Alexander Wilson. For a time, Audubon owned a general store, and Wilson came in to try to sell a subscription of his work American Ornithology. Audubon thought his illustrations were better, and that encounter sparked his interest in eventually publishing his work (perhaps to outdo Wilson’ work, which he eventually did).
  • The Birds of America was published between 1827-1838. It contained 435 life-sized watercolors on hand-engraved plates. Audubon insisted the birds be illustrated to scale, so he would position large birds in poses so that they would find the page. The pages of the double-elephant portfolio are 39 by 26 inches. Subscribers were sent sets of 5 prints per month (usually one large bird, one medium-sized, and three small birds).
  • The opening plate of The Birds of America is the Wild Turkey, a bird that Audubon was particularly fond of. He encountered his first Wild Turkey while on an expedition down the Ohio River.
audubon turkey
Wild Turkey print
  • There are 6 birds in the portfolio that are now extinct: the Passenger Pigeon, Carolina Parakeet, Labrador Duck, Pinnated Grouse, Great Auk, and Eskimo Curlew. Audubon identified 25 new species.
  • Audubon originally tried to find a publisher in Philadelphia, Pennsylvania, which during his time was the cultural and scientific center of the United States. However, he was met with enmity by the scientific community, many who believed Audubon was too conceited and remained loyal to ornithologist Alexander Wilson. Due to this failure, Audubon looked for a publisher in Liverpool, England. The British were fascinated by Audubon’s “American backwoodsman” image so much that he became extremely popular.
  • It took 14 years of studies, expeditions, and engraving to complete The Birds of America. 
  • Audubon not only loved illustrating birds, but enjoyed writing about them as well. Between 1831-1839 Audubon published Ornithological Biography, an octavo version that was 5 volumes. Ornithological Biography is an accompaniment to the prints where Audubon vividly describes his field observations and avian behavior.
  • A complete bound set of The Birds of America would sell today for upwards of $8,000,000. In 2000, a complete set sold at Christie’s, New York, for $8,802,500, setting the world auction record for any printed book. There are around 120 complete sets still in existence.
Audubon_Birds_of_America
Louisiana Heron on the cover of The Birds of America 

The love John James Audubon felt for birds will forever live on through The Birds of America. Ornithology was his passion, and through diligence and dedication, Audubon persevered to achieve his goal of his “Great Idea”. Happy birthday, John James Audubon! Thanks for being an inspiration to bird and nature lovers by sharing your passion with the world.

If you would like to see prints of the birds from The Birds of America, you can see them all on the National Audubon Society’s website:

John James Audubon Birds of America

What’s your favorite Audubon print? Tell me in the comments. (My favorites are the Great Horned Owl, Ospreys, and American White Pelican).

 

Blog-iversary!

Hi friends!

I realized that today is the 1 year anniversary of when I started BirdNation! I can’t believe it’s been a whole year. BirdNation has been a smaller part of a larger journey I’ve been embarking on the last few years.

Over the past few years, birds have had an incredible impact on my life. Learning about birds has opened up a whole new world for me, and has brought peace, wonder, and a deeper appreciation for all nature into my life that I was severely lacking. Until I starting birding, I didn’t realize how much of life I was actually missing out on. There was a whole new world to explore, and not just for birds, but anything relating to nature.

And as the years have been passing by, I’ve been changing. Craving a simpler existence than the life I have now. I’m a public school music teacher, and don’t get me wrong, that’s by no means a terrible existence. Teaching can be wonderful, but every year the nature of public school education becomes harder to handle. And I can feel the stress chipping away at me physically, mentally, and spiritually, so birding has become one of the few parts of my life (besides my wonderful family, friends, and pets) to bring me peace .

All of this got me thinking: what can I do to help renew myself? I love to teach and I love nature. Every time I read about climate change or environmental issue I always wish I can make more of a difference. And that’s when it struck me: maybe I should try to become an environmental educator.

So one fateful day in December 2015, I made a crazy choice: I enrolled in college as a biology major. I figured, what do I have to lose? I have a whole new world of possibilities waiting for me.

Now, I personally know people who think I’m insane for wanting to change fields. Yeah, maybe I am. And yes, I do know I have to make money to survive. I will. But taking a step forward is invigorating, and for the first time in awhile I’m excited for the future. I need to spread my wings and fly :-). Maybe I’ll land gracefully like a Carolina Chickadee, or land stumbling and awkwardly like a Laysan Albatross, but I’ll never know if I don’t try to soar. Besides, I have a back-up plan: to be a public school biology teacher, and avert my fate for becoming prematurely deaf (I’m a band teacher, so my world is very loud haha).

BirdNation was one of my first stepping stones to being an environmental educator. I thought that starting a blog solely about birds would be a great was to practice teaching others about the life of birds. I also wanted to connect with other people who are just as passionate about nature as I was.

And blogging has exceeded my expectations. I’m so happy to get to connect with you, my fabulous readers, who have brought me so much joy through your blogs. Thank you for spending your time reading my posts. You’ve helped me grow as an educator more than you know! There are so many awesome bird experiences to be had and things to learn about the avian world. I can’t wait to share them with you here at the blog.

I’m looking forward to another wonderful year of birds with you here at BirdNation!

yellow-warbler-singing

 

 

 

Mute Swan: Waterfowl Wednesday

For today’s Waterfowl Wednesday I decided to take break from ducks and talk about Mute Swans. Mute Swans are actually non-native to North America and considered by many as an “invasive” species.

Mute Swan (Cygnus olor)

Mute Swans are very conspicuous. They are entirely white; with large, heavy bodies and short legs. They usually hold their long, slender necks in an “S”-shape. Mute Swans have orange bills with a black base. Cygnets (young swans) have dusky brown plumage with a gray-black bill.

img_1280
Mute Swan in Cape May, NJ (Image by BirdNation)

Range:

Mute Swans are not native to North America, they are from Europe and Asia. They were introduced by Europeans in the late 19th century as an ornamental addition to estates and parks. A feral population formed and has spread throughout the Northeast,Great Lakes, and Pacific Northwest regions of the county.

Habitat:

Both fresh and saltwater ponds, lakes, lagoons, and bays. May closely associate with humans.

Diet:

Mainly aquatic vegetation, but also grasses, insects, small fish, snails, and frogs. They forage by dabbling, where they will submerge all their body except for their tail to reach food. They have huge appetites: Mute Swans can eat up to 8 pounds a day in aquatic vegetation. Many scientists consider them a nuisance because their enormous appetites put them in competition for food against native species and can degrade the environment.

img_1285
Foraging Mute Swans (Image by BirdNation)

Breeding/Nesting:

Mute Swans form pairs around the age of 2, and mate with the same partner for life. Courtship behavior includes facing each other which moving their heads in unison. When arriving at the breeding site, they will slapping their feet again the water to ward away intruders and announce their presence. Pairs will usually use the same nest site each year. Mute Swans are very territorial of their nest site. Their threat display is to arch their wings over their backs and fluff out their feathers.

Mute Swans have 1 brood per year with 5-7 eggs in a clutch, sometimes up to 10. The female will mainly incubate the eggs for about 36 days. The male will incubate the eggs while the female is out foraging. The pair’s nest is found on the shoreline in a small mound of plant material. Once the eggs hatch, both parents will tend to the cygnets, who they will usually carry on their backs. Mute cygnets come in one of two morphs (plumage variations): gray or white. The cygnets will fledge after 4-5 months, but usually remain with their family through the first winter.

450-178326282-mute-swan-in-water
Mute Swan giving her cygnets a ride (Image via buzzle.com)

Sounds:

Mute Swans are not actually mute, but they are quieter than North America’s native swans. Their voice is hoarse, and have a variety of calls; such as hissing, grunting, or a “bugle” sounding call. Their wingbeats are so loud that they can be heard from a mile away.

Conservation:

Mute Swan populations can have a negative impact on native species, such as Black Skimmers, Black Terns, and Least Terns. Due to their “invasive” nature, there have been efforts by habitat managers to control feral swan populations. In 2005, the Department of the Interior officially named them non-native and stripping them of their protection from the Migratory Bird Treaty Act, although some local state laws protect them. Despite the controversial efforts, populations have been increasing over the years.

Fun Facts:

  • Use caution when around Mute Swans, especially if you are nearby their nesting area or cygnets. They can be very aggressive and have been known to attack kayakers, canoes, and pedestrians who they feel are too close.
  • The two native North American swan species are the Tundra Swan and the Trumpeter Swan.
  • It’s very difficult to tell the difference between a male and female, but during breeding season the black base of the male’s bill will swell up to be larger than the female’s.

 

Hooded Merganser: Waterfowl Wednesday

When Dave and I went to Cape May in December, we saw a variety of waterfowl. Even with our binoculars, some of the birds were really far out so a few were hard to see. I was at home reviewing the pictures, and zoomed in on a picture of Bufflehead. But as I looked closer I realized “wait…those aren’t Bufflehead, they’re Hooded Mergansers!” . They blended in so well that I didn’t even realize I saw them on the trip until I got home. It’s always fun to find a little surprise like that, so today I’m featuring them as this week’s waterfowl.

Today’s post is dedicated to my mom because she suggested I write about mergansers (and we happen to have an inside joke about them lol).

Hooded Merganser (Lophodytes cucullatus)

Description:

Hooded Mergansers are the smallest of the 3 North American merganser species. ” Hoodies” have longs bodies, slender bills, and round tails. They are sexually dimorphic, so males and females have distinct plumage. Males have chestnut flanks, white underparts, and black upperparts. The males have a large, prominent white patch on the head that varies in size when its crest is raised or lowered. Females and juveniles are a dull gray-brown with a cinnamon-colored crest. Juveniles differ from females because or their dark bills (as opposed to the female’s yellow) and yellow eyes (female’s eyes are dark).

1-hooded-merganser-pair-bartley
Female and Male Hooded Mergansers (Image by Glenn Barley via birdzilla.com)

Range: 

Year-round: Northwest and Eastern United States Summers (breeding): Central to Eastern Canada; Great Lakes region of  the United States Winter: parts of the Western United States, parts of the Southeast, and Florida

Habitat:

Open water; wooded ponds, tidal creeks, marshes, swamps

Diet:

Fish, aquatic insects, vegetation, crustaceans, amphibians, and mollusks. Hoodies have a broader diet than other mergansers, who mainly eat fish. They dive underwater to find prey, which they catch by sight. The have nictitating membrance (a.k.a “third eyelid”) that protects their eyes while they hunt underwater.

Breeding/Nesting:

Hoodies court in large groups that typically consist of one female and many males. Male will put on a elaborate “head-throwing” display, where they toss their heads back with their crest raise while croaking. Females respond with head bobbing and a hoarse gack croak. Hooded Mergansers nest in tree cavities that the females line with down.They may also use nest boxes. Once the females lays her 10-12 eggs the male abandons her. It’s not known if pairs reunite the following year.

A male Hooded Merganser displaying for a female
A male demonstrate the “head throwing” display

A female will incubate her eggs for 26-41 days, but typically around 33. It’s common for a female to lay some of her eggs in another merganser’s nest, which is an example of brood parasitismThe ducklings will leave the nest within 24 hours after hatching. They are called by the female from below the tree and the duckling will “sky-dive” down to her. The chicks are able to dive shallowly and feed themselves, but the female will tend to them for several weeks. The ducklings fledge about 70 days after leaving the nest.

5818288768_9f3e925039_o_stuartoikawa
A female with her chicks (Image by Steward Oikawa via allaboutbirds.org)

Sounds:

Usually silent, except for during courtship. Males have a purr-like croak, sometimes being nicknames the “frog duck”. Females give a gack during courtship and sometimes a soft wrrep. In flight or when calling her chicks the female will use croo-croo-crook 

Conservation:

It’s thought that Hoodies have the smallest number of the 3 North American mergansers. Numbers have declined over the decades due to habitat loss. However, the population has slowly increasing, partly due to artifical nest boxes that are meant for Wood Ducks.

Fun Facts:

  • The female begins incubating her eggs after the last one is laid, therefore allowing for synchronous hatching. 
  • Hoodies are the second smallest merganser of the 6 merganser species in the world. The smallest is the Smew.
  • To protect the eggs or chicks, a female may use the “broken-wing” display to distract predators (similiar to the Killdeer).
  • Females only lay up to 13 eggs per brood, but due to brood parsitism (females laying eggs in each other’s nests), there have been nests found with up to 44 eggs in them!

Mystery of the Red Feathers

Hi friends! Sorry I disappeared for a bit. Being a second-time college student and full-time music teacher, I am currently in the midst of finals and concert season, so it’s been pretty hectic around here. I’m hoping to be back to writing more frequently in the next few days.

Instead of doing the normal Woodpecker Wednesday profile post, I wanted to share an interesting woodpecker study. There was a woodpecker mystery that was recently solved by scientists. The mystery: red feathers in Yellow-shafted Northern Flickers. The answer was not what scientists were expecting.

The Northern Flicker is the most abundant woodpecker in North America. Although pretty common, they are probably the most unusual of woodpeckers. They mainly feed on the ground on ants, are weak tree excavators, and even roost in trees less than other woodpeckers. Another unique feature is their intricate plumage, which is brown and tan or light peach, with black belly spots and a “zebra-back”.

When John Jame Audubon first saw Northern Flickers in 1843 at Yellowstone, Wyoming he was puzzled. He saw five Northern Flickers that all varied dramatically in plumage color. Some were red, some were yellow, and other were in between. He didn’t know it at the time, but he was in what is now considered “the hybrid zone”.

There are two subspecies of Northern Flickers: the “Red-shafted” Flicker of the west and the “Yellow-shafted” Flicker of the East. They frequently hybridize in the Great Plains region of the United States, south to Texas and north to Canada. This hybrid zone is at least 4,000 years old. Unless you live in the hybrid zone, you are most likely to see either one subspecies or the other.

Over a century later, scientist were puzzled one again about Flicker plumage. Starting the the 1960s, some biologists began to notice that there were Flickers over a 1,000 miles east of the hybrid zone with red feathers. But there weren’t quite as bright as the western “red-shafted” plumage, they were more of a copper color. Some ornithologists speculated that the color was being cause by genes from the red-shafted being spread to the yellow-shafted population. Something wasn’t quite right with that explanation though, so studies continued.

But now the mystery is solved! A recent study published on October 12, 2016 in The Auk revealed what was causing the color change. And it turns out hybridization has nothing to do with it.

The answer: honeysuckle berries.

Red-shafted Flickers have red feathers because of 4-keto-carotenoids, a type of pigment. The “red” Yellow-shafted Flickers get their color from a pigment called rhodoxanthin. Rhodoxanthin is rare in the wild and only found in certain plants. By eating berries from honeysuckle plants, particularly the Morrow’s, Tartarin, and their hybrid Bell’s honeysuckles, they are ingesting this pigment. These “red-yellow” Flickers are eating this food source around when they molt and acquire new plumage.

So why did it take scientist so long to solve this mystery? The Northern Flicker’s diet consists heavily of ants and other insects. Since berries is a smaller portion of their diet, the pigment they are eating is usually not as obvious, so it took scientists a longer time to notice.

Although this mystery is solved for the moment, there are so many other ornithological enigmas to the study (how about the mystery of the Ivory-billed Woodpecker?). But that’s the great thing about ornithology and other biological sciences: there are so many fascinating and exciting discoveries just waiting to be found.

If you want to read the actual study you can read it here:

The Auk Ornithological Advances

What kind of Northern Flickers do you see? Tell me about them in the comments.