Tag: Dark-eyed Juncos

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Seasonal Changes and Amazing Adaptations

Seasonal Changes and Amazing Adaptations: Click for a larger view of a Dark-eyed 'Oregon' Junco Male, Junco hyemalis montanus, Courtesy and copyright 2008 Ryan P. O'Donnell
Dark-eyed Junco “Oregon” Male
Junco hyemalis montanus
Courtesy & © 2008 Ryan P. O’Donnell 


Biking daily from Smithfield Canyon to USU campus, combined with an early am run, I’m well aware of the drop in temperatures, as are those of us who find themselves outdoors on a more permanent schedule. I’m speaking of our relatives who reside in the wild- birds, trees, raccoons, and such.

While I put on an extra layer or two, plants and animals have far more sophisticated adaptations from behavioral to physiological to structural.

We are all aware of the marvelous migration and hibernation behaviors, so let’s add a few more amazing adaptations to the list.

I’ll begin with a bird that is very common at our winter feeder- the Dark-eyed Junco. which responds to the first shortening days of summer with a series of physical changes: its reproductive organs become inactive and shrink in size, hormones stimulate the rapid growth of a new set of feathers, and fat deposits develop to provide fuel for the long migratory flight ahead.

Thus the preparation for migration starts as soon as the days begin to shorten. And the process must operate in reverse when the bird is in its winter habitat in the United States. As soon as days begin to lengthen, the Dark-eyed Junco must gear up physically for the flight north and breeding season. If it fails to do so, it likely won’t survive a long-distance migration. So the cycle of life and its related migrations and transitions are deeply connected to the heavens.

Plants are no less amazing. Those in temperate zones must also set their calendars accurately in order to flower and, for deciduous species, develop and drop leaves at the optimal time. Plants set their internal calendars using several attributes from the sunlight they receive. In fact, the angle of the sun may be more important to a plant than day length.

That’s because plant cells produce compounds called phytochromes in response to different portions of the light spectrum. Direct sunlight is higher in red light, while indirect sunlight contains more far-red light. During late fall and early winter, when the sun remains low in the southern sky, the indirect light produces an increase in far-red phytochromes.

As spring approaches and the arc of the sun rises in the sky, direct sunlight triggers the production of red phytochromes. The ratio of these two compounds mediates the hormones involved in flowering, leaf drop, and bud development. Even seeds below the soil are affected. The amount of red and far-red light that penetrate the soil is sufficient to govern germination.

Some behavioral alterations worth mention beyond migrating and hibernation are herding and flocking, huddling to share body warmth, dietary change, hair & feather change- both color and structure, and many more but my radio time is ending, so now it’s your turn to explore more! It really does make you appreciated the wonders of nature.

This is Jack Greene for Wild About Utah.

Credits:
Image: Courtesy and copyright 2008 Ryan P. O’Donnell
Text:     Jack Greene, Bridgerland Audubon Society


Additional Reading:

Dark-eyed Junco, Junco hyemalis, Aynsley Carroll, Animal Diversity Web, https://animaldiversity.org/accounts/Junco_hyemalis/

Dark-eyed Junco, Junco hyemalis, Aynsley Carroll, Boreal Songbird Initiative, https://www.borealbirds.org/bird/dark-eyed-junco

https://scholar.google.com/scholar?q=junco+winter+reproductive+cycles

Jigang Lia, Gang Lib, Haiyang Wangb, and Xing Wang Denga, Phytochrome Signaling Mechanisms, The Arabidopsis Book, American Society of Plant Biologists, 2011, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3268501/ pdf

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Dark-eyed Juncos

Click for a larger view of a Dark-eyed 'Oregon' Junco Male, Junco hyemalis montanus, Courtesy and copyright 2008 Ryan P. O'Donnell
Dark-eyed Junco “Oregon” Male
Junco hyemalis montanus
Courtesy & © 2008 Ryan P. O’Donnell 

Click for a larger view of a Dark-eyed 'Oregon' Junco Female, Junco hyemalis montanus, Courtesy and copyright 2011 Ryan P. O'DonnellDark-eyed Junco “Oregon” Female
Junco hyemalis montanus
Courtesy & © 2011 Ryan P. O’Donnell 

Click for a larger view of a Dark-eyed 'Pink Sided' Junco, Junco hyemalis mearnsi, Courtesy and copyright 2011 Ryan P. O'DonnellDark-eyed Junco “Pink Sided”
Junco hyemalis mearnsi
Courtesy & © 2011 Ryan P. O’Donnell 

Click for a larger view of a Dark-eyed 'Cassiar' Junco, Junco hyemalis cismontanus, Courtesy and copyright 2011 Ryan P. O'DonnellDark-eyed Junco “Cassiar”
Junco hyemalis cismontanus
Courtesy & © 2011 Ryan P. O’Donnell 

Click for a larger view of a Dark-eyed 'Gray-headed' Junco, Junco hyemalis caniceps, Courtesy and copyright 2011 Ryan P. O'DonnellDark-eyed Junco “Gray-headed”
Junco hyemalis caniceps
Courtesy & © 2011 Ryan P. O’Donnell 

My backyard bird feeders are a busy place this time of year. I enjoy keeping track of who visits – especially as a relative newcomer to the Utah bird scene. Last winter, however, I was baffled by the identity of what turned out to be a fairly ordinary bird.

Dark-eyed juncos are a common sight throughout the United States, but as it turns out, they exhibit an incredible geographic variation in plumage colors. There is a ‘slate-colored race’ which I was used to seeing in the Midwest – uniformly gray above with a white underbody. During Utah winters, the ‘Oregon race’ is common, with its black hood, brown back and peachy sides. Another ‘gray-headed race’ sports varying shades of gray with a distinct reddish brown patch on its back.

Depending on who you ask, there are up to fifteen different races, also called sub-species, of dark-eyed junco – all quite visually distinct, but all considered to be the same species. It wasn’t always this way, however. In the late 1950’s what we now call dark-eyed juncos were recognized as four different species, and in the 1890’s there were six.

These changes beg the question, at what point does speciation occur? And the answer lies in the ability of these birds to interbreed. One scientific definition of a species is those organisms or populations of organisms that are “potentially capable of interbreeding.”

Unique plumage patterns have evolved in a number of geographic locations across the junco’s range, however all of the dark-eyed junco variants could potentially interbreed if they happened to meet. Indeed in places where these geographic territories overlap inter-breeding does take place resulting in blends of the usually-distinct color patterns.

Juncos aren’t the only bird species with recognized color variants. Any raptor enthusiast will be familiar with variations in plumage colors that many birds of prey exhibit, such as merlins and red-tailed hawks. What makes dark-eyed juncos unique is that they are being studied as a possible case of speciation in progress. It turns out that there is more than just a difference in color among dark-eyed juncos. Some sub-species also exhibit variation in song patterns, social behavior, body size, and migration patterns, any of which may eventually cause these groups to stop interbreeding and allow a new species to emerge.

To see pictures of dark-eyed junco subspecies, visit our website at www.wildaboututah.org. Thank you to Rocky Mountain Power Foundation for supporting the research and development of this Wild About Utah topic.

For the Stokes Nature Center and Wild About Utah, this is Andrea Liberatore.

Credits:

Photos: Courtesy & © Ryan P. O’Donnell
Text:    Andrea Liberatore, Stokes Nature Center, logannature.org

Additional Reading:

Atwell, J.W., O’Neal, D.M, and Ketterson, E.D. (2011) Animal Migration as a Moving Target for Conservation: Intra-species Variation and Responses to Environmental Change, as Illustrated in a Sometimes Migratory Songbird. Environmental Law. Vol. 41:289 p. 289-319, https://www.amazon.com/Animal-migration-moving-target-conservation/dp/B005C29H7I

Alderfer, Jonathan (editor) (2005) National Geographic Complete Book of Birds. National Geographic Press. Dark-eyed junco information available online at: https://animals.nationalgeographic.com/animals/birding/dark-eyed-junco/

Cornell Lab of Ornithology, All About Birds: Dark-eyed Junco. https://www.allaboutbirds.org/guide/Dark-eyed_Junco/id/ac

History of Name Changes for Juncos. Cornell Lab of Ornithology. https://www.birds.cornell.edu/pfw/News/junco_taxonomy.pdf

Posted on

Dark-eyed Juncos

Click for a larger view of a Dark-eyed 'Oregon' Junco Male, Junco hyemalis montanus, Courtesy and copyright 2008 Ryan P. O'Donnell
Dark-eyed Junco “Oregon” Male
Junco hyemalis montanus
Courtesy & © 2008 Ryan P. O’Donnell 

Click for a larger view of a Dark-eyed ''Oregon'' Junco Female, Junco hyemalis montanus, Courtesy and copyright 2011 Ryan P. O'DonnellDark-eyed Junco “Oregon” Female
Junco hyemalis montanus
Courtesy & © 2011 Ryan P. O’Donnell 

Click for a larger view of a Dark-eyed ''Pink Sided'' Junco, Junco hyemalis mearnsi, Courtesy and copyright 2011 Ryan P. O'DonnellDark-eyed Junco “Pink Sided”
Junco hyemalis mearnsi
Courtesy & © 2011 Ryan P. O’Donnell 

Click for a larger view of a Dark-eyed ''Cassiar'' Junco, Junco hyemalis cismontanus, Courtesy and copyright 2011 Ryan P. O'DonnellDark-eyed Junco “Cassiar”
Junco hyemalis cismontanus
Courtesy & © 2011 Ryan P. O’Donnell 

Click for a larger view of a Dark-eyed ''Gray-headed'' Junco, Junco hyemalis caniceps, Courtesy and copyright 2011 Ryan P. O'DonnellDark-eyed Junco “Gray-headed”
Junco hyemalis caniceps
Courtesy & © 2011 Ryan P. O’Donnell 

My backyard bird feeders are a busy place this time of year. I enjoy keeping track of who visits – especially as a relative newcomer to the Utah bird scene. Last winter, however, I was baffled by the identity of what turned out to be a fairly ordinary bird.

Dark-eyed juncos are a common sight throughout the United States, but as it turns out, they exhibit an incredible geographic variation in plumage colors. There is a ‘slate-colored race’ which I was used to seeing in the Midwest – uniformly gray above with a white underbody. During Utah winters, the ‘Oregon race’ is common, with its black hood, brown back and peachy sides. Another ‘gray-headed race’ sports varying shades of gray with a distinct reddish brown patch on its back.

Depending on who you ask, there are up to fifteen different races, also called sub-species, of dark-eyed junco – all quite visually distinct, but all considered to be the same species. It wasn’t always this way, however. In the late 1950’s what we now call dark-eyed juncos were recognized as four different species, and in the 1890’s there were six.

These changes beg the question, at what point does speciation occur? And the answer lies in the ability of these birds to interbreed. One scientific definition of a species is those organisms or populations of organisms that are “potentially capable of interbreeding.”

Unique plumage patterns have evolved in a number of geographic locations across the junco’s range, however all of the dark-eyed junco variants could potentially interbreed if they happened to meet. Indeed in places where these geographic territories overlap inter-breeding does take place resulting in blends of the usually-distinct color patterns.

Juncos aren’t the only bird species with recognized color variants. Any raptor enthusiast will be familiar with variations in plumage colors that many birds of prey exhibit, such as merlins and red-tailed hawks. What makes dark-eyed juncos unique is that they are being studied as a possible case of speciation in progress. It turns out that there is more than just a difference in color among dark-eyed juncos. Some sub-species also exhibit variation in song patterns, social behavior, body size, and migration patterns, any of which may eventually cause these groups to stop interbreeding and allow a new species to emerge.

To see pictures of dark-eyed junco subspecies, visit our website at www.wildaboututah.org. Thank you to Rocky Mountain Power Foundation for supporting the research and development of this Wild About Utah topic.

For the Stokes Nature Center and Wild About Utah, this is Andrea Liberatore.

Credits:

Photos: Courtesy & © Ryan P. O’Donnell
Text:    Andrea Liberatore, Stokes Nature Center, logannature.org

Additional Reading:

Atwell, J.W., O’Neal, D.M, and Ketterson, E.D. (2011) Animal Migration as a Moving Target for Conservation: Intra-species Variation and Responses to Environmental Change, as Illustrated in a Sometimes Migratory Songbird. Environmental Law. Vol. 41:289 p. 289-319, https://www.amazon.com/Animal-migration-moving-target-conservation/dp/B005C29H7I

Alderfer, Jonathan (editor) (2005) National Geographic Complete Book of Birds. National Geographic Press. Dark-eyed junco information available online at: https://animals.nationalgeographic.com/animals/birding/dark-eyed-junco/

Cornell Lab of Ornithology, All About Birds: Dark-eyed Junco. https://www.allaboutbirds.org/guide/Dark-eyed_Junco/id/ac

History of Name Changes for Juncos. Cornell Lab of Ornithology. https://www.birds.cornell.edu/pfw/News/junco_taxonomy.pdf

Posted on

Dark-eyed Juncos

Dark-eyed Junco “Oregon” Male
Junco hyemalis montanus
Courtesy & © 2008 Ryan P. O’Donnell 

Dark-eyed Junco “Oregon” Female
Junco hyemalis montanus
Courtesy & © 2011 Ryan P. O’Donnell 

Dark-eyed Junco “Pink Sided”
Junco hyemalis mearnsi
Courtesy & © 2011 Ryan P. O’Donnell 

Dark-eyed Junco “Cassiar”
Junco hyemalis cismontanus
Courtesy & © 2011 Ryan P. O’Donnell 

Dark-eyed Junco “Gray-headed”
Junco hyemalis caniceps
Courtesy & © 2011 Ryan P. O’Donnell 

My backyard bird feeders are a busy place this time of year. I enjoy keeping track of who visits – especially as a relative newcomer to the Utah bird scene. Last winter, however, I was baffled by the identity of what turned out to be a fairly ordinary bird.

Dark-eyed juncos are a common sight throughout the United States, but as it turns out, they exhibit an incredible geographic variation in plumage colors. There is a ‘slate-colored race’ which I was used to seeing in the Midwest – uniformly gray above with a white underbody. During Utah winters, the ‘Oregon race’ is common, with its black hood, brown back and peachy sides. Another ‘gray-headed race’ sports varying shades of gray with a distinct reddish brown patch on its back.

Depending on who you ask, there are up to fifteen different races, also called sub-species, of dark-eyed junco – all quite visually distinct, but all considered to be the same species. It wasn’t always this way, however. In the late 1950’s what we now call dark-eyed juncos were recognized as four different species, and in the 1890’s there were six.

These changes beg the question, at what point does speciation occur? And the answer lies in the ability of these birds to interbreed. One scientific definition of a species is those organisms or populations of organisms that are “potentially capable of interbreeding.”

Unique plumage patterns have evolved in a number of geographic locations across the junco’s range, however all of the dark-eyed junco variants could potentially interbreed if they happened to meet. Indeed in places where these geographic territories overlap inter-breeding does take place resulting in blends of the usually-distinct color patterns.

Juncos aren’t the only bird species with recognized color variants. Any raptor enthusiast will be familiar with variations in plumage colors that many birds of prey exhibit, such as merlins and red-tailed hawks. What makes dark-eyed juncos unique is that they are being studied as a possible case of speciation in progress. It turns out that there is more than just a difference in color among dark-eyed juncos. Some sub-species also exhibit variation in song patterns, social behavior, body size, and migration patterns, any of which may eventually cause these groups to stop interbreeding and allow a new species to emerge.

To see pictures of dark-eyed junco subspecies, visit our website at www.wildaboututah.org. Thank you to Rocky Mountain Power Foundation for supporting the research and development of this Wild About Utah topic.

For the Stokes Nature Center and Wild About Utah, this is Andrea Liberatore.

Credits:

Photos: Courtesy & © Ryan P. O’Donnell
Text:    Andrea Liberatore, Stokes Nature Center, logannature.org

Additional Reading:

Atwell, J.W., O’Neal, D.M, and Ketterson, E.D. (2011) Animal Migration as a Moving Target for Conservation: Intra-species Variation and Responses to Environmental Change, as Illustrated in a Sometimes Migratory Songbird. Environmental Law. Vol. 41:289 p. 289-319, https://www.amazon.com/Animal-migration-moving-target-conservation/dp/B005C29H7I

Alderfer, Jonathan (editor) (2005) National Geographic Complete Book of Birds. National Geographic Press. Dark-eyed junco information available online at: https://animals.nationalgeographic.com/animals/birding/dark-eyed-junco/

Cornell Lab of Ornithology, All About Birds: Dark-eyed Junco. https://www.allaboutbirds.org/guide/Dark-eyed_Junco/id/ac

History of Name Changes for Juncos. Cornell Lab of Ornithology. https://www.birds.cornell.edu/pfw/News/junco_taxonomy.pdf