Category: Vertebrates

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Bald Eagles

Bald Eagle Feeding
Copyright © 2011 Bryant Olsen

Bald Eagle in Flight
Copyright © 2011 Bryant Olsen

Juvenile Bald Eagle in Flight
Copyright © 2011 Terry Greene

Flying Immature Bald Eagle
Copyright © 2011 Terry Greene

Flying Immature Bald Eagle

Copyright © 2011 Terry Greene, Photographer

When winter arrives in Utah, a number of our bird species hit the road – some flying thousands of miles to Mexico and Central America in search of a warm winter home.

But there is one notable bird that actually migrates to Utah in the winter – the bald eagle. In general, birds migrate because of seasonal food shortages. Think of the hummingbirds that rely on flower nectar and insects, which Utah cannot provide in winter, but which are abundant other times of the year. The same is true for bald eagles, whose main food source is fish. Winter comes on strong in Alaska and Canada, freezing lakes, ponds, and all but the strongest flowing rivers. So the birds travel to seek out the relatively mild winters found farther south.

One of the largest birds of prey you’ll see in our Utah skies, a mature bald eagle can have a wingspan of 6 to 8 feet and stand almost three feet tall. Only the golden eagle rivals it in size. Pairs are thought to mate for life, and they are also responsible for the largest nests of any bird in North America. One record-setting abode measured 9 feet wide, 20 feet deep, and weighed more than 2 tons.

And to think, we almost lost this incredible species. Since DDT and hunting heavily affected bald eagle numbers in the early half of the 20th century, the birds have made a truly remarkable comeback. From a low point around 4,000 individuals in the lower 48 states, they are now thought to number in the tens of thousands, and have been removed from the Threatened and Endangered Species lists.

Perhaps as their comeback continues, Utah will once again see these majestic animals make their massive nests here, fishing in our many rivers and lakes year round. For now, though, aside from a few rare exceptions, bald eagle enthusiasts will have to make the most of their short winter stay. To observe bald eagles, consider a visit to the Great Salt Lake Nature Center at Farmington Bay. Every year, the Bay plays host to hundreds of eagles, from November to March, and while this milder-than-usual winter has brought in fewer numbers of eagles, you may still be able to catch a glimpse. They will likely be heading north later this month, however, so don’t delay. And be sure to keep your ears tuned into the bald eagle’s haunting song:

[Bald Eagle call from Songbirds of Yellowstone, Kevin Colver]

Thank you to the 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.

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

Credits:

Audio: Courtesy & Copyright Kevin Colver
Photos: Courtesy & Copyright Bryant Olsen and
            Courtesy & Copyright Terry Greene
Text:    Andrea Liberatore, Stokes Nature Center, logannature.org

Additional Reading:

Parrish, J. and Walters, B., Editors. (2009) Bald Eagle (Haliaeetus leucocephalus). Utah Division of Wildlife Resources: Wildlife Notebook Series No. 3. https://wildlife.utah.gov/publications/pdf/2010_bald_eagle.pdf

National Geographic Society (2012) Animals: Bald Eagle (Haliaeetus leucocephalus)
https://animals.nationalgeographic.com/animals/birds/bald-eagle/

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Western Banded Gecko

Western Banded Gecko, Courtesy NPS
Western Banded Gecko
Courtesy NPS

They might catch your eye as they dart under sagebrush. Or maybe startle you with their pushups on a boulder. Odds are, you won’t leave Arches or Canyonlands national parks without seeing a Western Banded Gecko.

These lizards can grow to six inches in length, though that’s on the large side, and half of that length might be their tail. Pale-pink and brown-banded translucent skin distinguishes Western Banded Geckos from all other lizards that live in the same desert surroundings, and their heads and bodies are speckled with light brown. The brown bands are vibrant in young Western Banded Geckos, and then change into blotches, or spots, with age.

The small scales that cover their body are soft to touch, and their slender toes leave no room for pads. Movable eyelids and vertical pupils also set them apart.

The Western Banded Gecko typically are spotted in rocky or sandy desert areas in the American Southwest. They are fond of open, dry deserts, desert grasslands, and catching the sun in the canyons. You can spot them, or one of the eight subspecies, in Glen Canyon National Recreation Area, as well as in Arches and Canyonlands.

Like other geckos, these lizards generally avoid the day heat and prefer the cool night air. They seek shelter during the day near or under rocks, burrows, and spaces beneath vegetative debris, and even trash piles if necessary. They frequent rodent burrows as they hunt insects, spiders, small arthropods, and baby scorpions.

The Western Banded Gecko stalks its prey, capturing and crushing it with its jaws in a final, fatal lunge. The small gecko is one of the few reptiles credited with controlling the scorpion population, by eating their young. The Western Banded Gecko can also mimic a scorpion, by turning its tail upwards, and waving it to repel predators.

In addition to this deception, Western Banded Geckos use other methods to divert predators. Be forewarned: if you plan on catching a Western Banded Gecko, be prepared to hear a squeak or chirp in disagreement. You may even see them detach their tail. Their tail has particular fracture planes, allowing the lizard to easily detach and escape, similar to other lizards. Blood vessels surrounding the tail rapidly close, so they can prevent blood loss. Regrowth of their tails happens quickly, as it is mostly made up of cartilage.

Though the tail serves as an easy escape route, it means a lot to a Western Banded Gecko: that’s where it stores its food and water. Their tail allows these animals to survive during lean times, up to nine months. As you can imagine, losing a tail puts their life in danger, so look but don’t touch.

For Wild About Utah and National Parks Traveler, I’m Kurt Repanshek.

Credits:
Image: Courtesy and Copyright Kurt Repanshek, www.nationalparkstraveler.com
Text:     Kurt Repanshek, NationalParksTraveler.com.


Additional Reading:

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Wilderness 16 Feb 2015

Wilderness. The word conjures up romantic images of wide open landscapes teeming with birds, beasts, and plants. I imagine places untouched by human influence – truly wild and free. Places that are exotic and far away.

High Unitas Wilderness, Utah, Courtesy Wilderness.net, Copyright 2009 Cordell Andersen, Photographer www.cordellmandersen.com
High Unitas Wilderness, Utah
Courtesy Wilderness.net
Copyright © 2009 Cordell Andersen, Photographer

Red Butte Wilderness, Utah, Courtesy Wilderness.net, Copyright 2011 Paul Gooch, PhotographerRed Butte Wilderness, Utah
Courtesy Wilderness.net
Copyright © 2011 Paul Gooch, Photographer

Wellsville Mountain Wilderness, Utah, Courtesy Wilderness.net, Copyright 2011, Dusty Vaughn, PhotographerWellsville Mountain Wilderness, Utah
Courtesy Wilderness.net
Copyright © 2011 Dusty Vaughn, Photographer

Paria Canyon, Vermilion Cliffs Wilderness, Courtesy Wilderness.net, Copyright © 2011 Mike Salamacha, Paria Ranger, BLM, PhotographerParia Canyon
Vermilion Cliffs Wilderness
Courtesy Wilderness.net
Copyright © 2011 Mike Salamacha, Paria Ranger, BLM, Photographer

 

But wilderness exists much closer than you may think.

The United States Congress adopted the Wilderness Act with a nearly unanimous vote in 1964. Ours was the first country in the world to define and designate wilderness areas – lands valued enough to be set aside for the purpose of protection.

Currently, the Wilderness Act protects 757 individual wilderness areas across the United States – totaling more than 109 million acres. Thirty-three wilderness areas are found in Utah, and they protect a variety of unique landscapes from the red rock desert found in Red Butte Wilderness to the alpine forests of the High Uintas Wilderness. While the landscapes may look incredibly different from one wilderness area to the next, these lands share a number of qualities which can be described by adjectives such as peaceful, quiet, untouched, and pristine.

These areas protect some of the most unique and incredible landscapes that Utah has to offer, but that doesn’t mean they’re off limits. Our wilderness areas are just that – ours. They are public lands, accessible to anyone who wants to visit – so long as you tread lightly.

Areas that fall under its protection are described in the Wilderness Act as “lands designated for preservation and protection in their natural condition…” which “…shall be devoted to the public purposes of recreation, scenic, scientific, educational, conservation and historic use.” These amazing lands were set aside in 1964 with an eye to the future and because of it, should still be around for your grandchildren’s grandchildren to enjoy.

There is an ongoing effort to educate Americans about the immense value of preserving wilderness areas. For without education, they may one day be selfishly reclaimed and lost. One of these educational opportunities is coming to Logan on April 13th and 14th. The Arthur Carhart National Wilderness Training Center will be hosting a teacher training workshop in conjunction with the Stokes Nature Center and the Utah Society for Environmental Education. The workshop is aimed at teachers in grades 5-8, though anyone is welcome to attend. For more information, please contact the Stokes Nature Center at www.logannature.org

Not a teacher? The best way to learn about wilderness areas is to go visit one! Information, and photos of Utah Wilderness Areas, can be found at www.wildaboututah.org

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

Credits:

Photos: Courtesy Wilderness.net, Steve Archibald, (Individual Copyrights noted)
Text:    Andrea Liberatore, Stokes Nature Center, logannature.org

Additional Reading:
The Arthur Carhart National Wilderness Training Center:
wilderness.net

Wilderness Investigations teacher training workshop:
logannature.org/wi_workshop

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Robins in Winter

American Robin
American Robin
Turdus migratorius
Courtesy US FWS, images.fws.gov
Dr. Thomas G. Barnes, Photographer
 

Robin with Chicks in NestAmerican Robin
Turdus migratorius
Courtesy US FWS, images.fws.gov
Lee Karney, Photographer
 

Robin with Chicks in NestRobin with Chicks in Nest
Courtesy US FWS, images.fws.gov
James C. Leopold, Photographer

The American robin with its abundance, red breast, and loud song is one of the most recognizable backyard birds in North America. For many of us the robin – or Turdus migratorius – is also thought of as a herald of spring. So why is it that we still occasionally see them in our wintry Utah backyards?

Seasonal bird migration can be triggered by a number of things, but the two main drivers are food supply and nesting habitat. In spring and summer the birds move northward to take advantage of insect hatches, budding plants, and the plethora of nesting sites. Then, as food sources dwindle in fall, the birds move southward to areas where the necessary resources are still plentiful.

The distances birds migrate in order to access these resources can range widely. Therefore, birds are generally categorized as being short-, medium-, or long-distance migrants. Robins are considered short-distance migrants. While their range spans all of Canada and the United States extending down into Mexico, most robins do not travel far from their breeding grounds in winter and may not leave at all. Only the populations that breed and reside on the edges of this range will migrate seasonally.

The robin’s varied diet and behavioral adaptability are the primary reasons these short-migratory or non-migratory patterns are possible. Robins are preferably ground foragers, feasting on insects and earthworms in the spring and summer months. Yet, during the fall and winter, robins eat a fruit-based diet. They track this seasonal food source in flocks, abandoning their summer individualistic and territorial behavior. These flocks – or roosting aggregates – also help them survive the cold winter temperatures. As a result, robins are able to cope with the ground freezing, the disappearance of their preferred food source, and the harsh winter weather.

Returning to our original question: is the American robin truly a sign of spring here in Utah? Is it strange to see this bird in our backyards during the winter months? The simple answer is no. Robins can be found year round almost anywhere south of Canada. While they may migrate nomadically, staying or leaving areas as weather and snow cover affect their food supply, there could be some keeping us company in Utah all winter.

For Wild About Utah, I’m Anna Bengtson.

Credits:
Image: Courtesy US FWS, Lee Karney, James C. Leopold, Photographers
Text: Anna Bengston

Sources & Additional Reading:

American Robin Profile, Utah Birds https://utahbirds.org/birdsofutah/BirdIndex.htm

American Robin, Cornell Lab of Ornithology https://www.allaboutbirds.org/guide/american_robin/id

American Robin, The Birds of North America Online https://bna.birds.cornell.edu/bna/species/462/articles/introduction

Studying Migration, Cornell Lab of Ornithology https://www.birds.cornell.edu/AllAboutBirds/studying/migration/

Migration Patterns, Cornell Lab of Ornithology https://www.birds.cornell.edu/AllAboutBirds/studying/migration/patterns

Where Have all the Robins Gone?, Migration, Cornell Lab of Ornithology https://www.birds.cornell.edu/AllAboutBirds/faq/master_folder/migration/document_view

Snow Depth Survey, The Great Backyard Bird Count https://www.birdsource.org/gbbc/science-stories/past-stories/snow-depth-survey

Winter Robins, The Great Backyard Bird Count https://www.birdsource.org/gbbc/science-stories/past-stories/is-that-winter-flock-of-robins-in-your-yard-unusual

Kelly, Patrick, A Moral Dilemma, Wild About Utah, June 29, 2020, https://wildaboututah.org/a-moral-dilemma/

Bengston, Anna, Robins in Winter, Wild About Utah, March 13, 2014, https://wildaboututah.org/robins-in-winter/

Bengston, Anna, American Robin, Wild About Utah, January 18, 2016, https://wildaboututah.org/american-robin-160118/

Bingham, Lyle, Richard Hurren(voice), The Occupants on Robin Street, Wild About Utah, July 8, 2008, https://wildaboututah.org/the-occupants-on-robin-street/