Birds of a Feather

Written by Kristine Manganelli-Rappaport (Somerset County 4-H Program Coordinator)

Here in New Jersey we entered winter back on December 21 and even had our first snow! This time of year when temperatures drop and everything is blanketed in a layer of white, makes it seem like all of the animals have decided to stay hidden and cozied away. But if you pay attention, you will realize that nature is always active, and you will find clues all around. Perhaps you spot deer tracks in the snow or find a fallen feather on the ground.

The cold weather makes food like plants and berries less abundant for animals so they have to look harder to find it. One of my favorite things to do is put bird feeders in my yard. This helps provide food for the birds and has the added benefit of bringing beautiful avian visitors to watch and appreciate.

Since National Bird Day was on January 5, it is the perfect time to explore the birds that stay in our area all winter long and are commonly found stopping by feeders for a snack. Birds play a critical role in our ecosystem as pollinators and seed dispersers for plants and trees. There are around 10,000 species of birds worldwide, and over 450 species found in New Jersey.

The backdrop of white really makes certain birds stand out like beautiful Blue Jays, our yellow state bird the American Goldfinch, and ruby-red Northern Cardinals. Let’s dive a little deeper into what makes these birds so colorful!

Blue Jay

Blue is a color that does not often occur in nature. When it comes down to it, Blue Jays are not really blue. If you flip a Blue Jay feather upside down, it actually appears grey. This is because the feathers do not contain blue pigment. Blue is considered a structural color (vs. a pigmented color) because it is only generated when light interacts with a feather’s arrangement. We see the feather as blue because of the way it interacts with light through a process called light scattering.

Bird feathers contain a protein called keratin. The structure of keratin allows light to twist and separate into a rainbow of colors, similar to how a prism works, by scattering the longer wavelengths of light and reflecting shorter ones.

Along with keratin, Blue Jay feathers contain air pockets that causes only one color to be displayed at a time. The air pockets are microscopic and are considered nanostructures. When light strikes a blue feather, the keratin pattern causes red and yellow wavelengths to cancel each other out, while blue wavelengths of light amplify one another and reflect back to our eye. Different shapes and sizes of these air pockets and keratin make different shades of blue. This effect is not unique to Blue Jays; all blue birds are not really blue.

American Goldfinch

The American Goldfinch shows off its brightest yellow hues in spring and summer during mating season. In the bird world, bright colors are often associated with males hoping to attract a mate. Female Goldfinches are a much paler shade of yellow throughout the year. Studies show that the brighter the bird, the more successful they will be at reproducing and these traits are passed to their offspring.

The golden color comes from pigment molecules called carotenoids that create shades of yellow, orange, and red. Goldfinch feathers absorb these pigments from their diet of carotenoid-rich seeds. Carotenoids produce pigmented colors that do not require interaction with light to be seen like the structural color blue.

Once autumn hits, they molt, which is the process of losing and regrowing feathers. Most birds go through this process about once per year to replace worn feathers. By winter, the male Goldfinch will look very similar in appearance to a female. Birds also molt to duller colors in order to blend into their surroundings during the barren winter, helping them to avoid being spotted by predators.

Northern Cardinal

Another bird that dons colorful plumage is the bright red, Northern Cardinal. Unlike other bird species who molt into faded colors for the winter, Northern Cardinals do molt, but by winter their feathers reach the peak of brilliance ahead of the spring breeding season. The male Northern Cardinal is deep red in color, while the females are a duller reddish-brown color.

Like Goldfinches, the red color in Cardinal feathers comes from carotenoids. These are found in the food that they eat such as raspberries, winterberry, sumac berries, and even poison ivy berries, but the favorite are the red berries from Dogwood trees. They also love native honeysuckle which produces carotenoid-rich berries.

If you zoom in on a feather, the barbs or thin hair-like parts that grow out of the feather’s shaft have several layers. When it comes to cardinals, the carotenoids accumulate in the cortex, or outer-most layer of each barb. This means the pigment or coloration is on the surface of the feather, not within the deeper layers.

Get Outside: The best way to observe these birds is to attract them to your yard using bird feeders. You can purchase one, or make a homemade version using apples or oranges. Hang them in areas you can view from your house and use binoculars for a closer look if you have them.

Homemade Feed Instructions: https://runwildmychild.com/easy-bird-feeders-kids/

Check out this awesome opportunity for 5th graders: 2022 Species on the Edge Art and Essay Contest- Hosted by the Conserve Wildlife Foundation of New Jersey

Empowers 5th grade students to advocate for an endangered or threatened species from New Jersey through a well-researched, creative essay and original art piece. Simple, Fun, and Free to Enter!

Open to all New Jersey 5th grade students. One winner from each county will be selected. The contest kit (including rules, species list, & entry form) can be downloaded below.

http://www.conservewildlifenj.org/education/edge/

ENTRIES ARE BEING ACCEPTED THROUGH FEBRUARY 14, 2022 BY MAIL AND ONLINE.

Mail your artwork, essay, and entry form to:

Conserve Wildlife Foundation of New Jersey

2 Preservation Place

Princeton, NJ 08540

Email a scan/digital photo of your artwork, essay, and entry form to:

Ethan.Gilardi@conservewildlifenj.org

Contest winners who have submitted their artwork electronically will be required to mail their artwork to CWF for inclusion in our calendar and statewide exhibitions.

Sources:

“Are Cardinals Redder in Winter?” The Cornell Lab of Ornithology, December 2021, https://www.allaboutbirds.org/news/are-cardinals-brighter-in-winter/. Accessed 11 Jan. 2022.

“Food and Feeder Preferences of Common Feeder Birds.” Project Feeder Watch, The Cornell Lab of Ornithology, https://feederwatch.org/learn/common-feeder-birds/. Accessed 11 Jan. 2022.

“For Male Cardinals, the Redder the Better.” National Audubon Society, June 2020, https://www.audubon.org/news/for-male-cardinals-redder-better. Accessed 11 Jan. 2022.

Goldman, Jason G. “What Makes Bird Feathers So Colorfully Fabulous?” National Audubon Society, March 2016, https://www.audubon.org/news/what-makes-bird-feathers-so-colorfully-fabulous. Accessed 11 Jan. 2022.