Tag: Bird Migration

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BirdCast Dashboard Shows
Peak Need for Dark Skies
and the Mantra to
Dim the Lights for Birds at Night

Milky Way above Chesler Park Canyonlands National Park Courtesy US National Park Service, Emily Ogden, Photographer

Milky Way above Chesler Park
Canyonlands National Park
Courtesy US National Park Service,
Emily Ogden, Photographer
Canyonlands is one of many parks in southern Utah with the International Dark Sky Park designation

 
BirdCast Migration Dashboard https://dashboard.birdcast.info/ Courtesy BirdCast, The Cornell Lab of Ornithology Cornell University

BirdCast Migration Dashboard
https://dashboard.birdcast.info/
Courtesy BirdCast, The Cornell Lab of Ornithology
Cornell University

Songbirds migrate at night to avoid predators, air turbulence, and daytime heat. Down here on the ground we are unaware of the miraculous and essential voyagers flying up to 10,000 feet above us, but thanks to dedicated scientists collaborating for years on end we have free access to the data and graphs of these massive population shifts. The BirdCast Dashboard uses weather radar to track bird migrations, providing real time data showing peak migrations at the website dashboard.birdcast.info.

Did you know that World Migratory Bird Day is celebrated in May and October? Those are the peak months for spring and fall migrations, and the magnitudes of those flocks are considerable. Two thirds of songbirds migrate at night, and on the evening of Sunday, May 15, 2022, one million one hundred and fifty one thousand five hundred (1,151,500) birds crossed Cache County, Utah! Yes, 1,151,500 birds crossed Cache County, Utah, in one night!

It’s important to know when migrations are occurring because skyglow from artificial lighting causes bird disorientation and millions of bird fatalities each and every year. The declining bird population is problematic for many reasons, not least of which because some of the most intrepid travelers like the three-inch-long Rufous Hummingbird, which travels 3,900 miles each way from Alaska to Mexico, are keystone species with ecosystem services such as pollination and consumption of pests such as aphids and mosquitoes.

The Bobolink travels 12,500 miles to and from southern South America every year – those imperiled birds breeding at the west end of Logan may travel the equivalent of 4 or 5 times around the circumference of the earth throughout their lifetime. They come to Cache Valley for the habitat, stay to raise their young, and then head back to their distant winter feeding grounds.

A few top-notch steps toward bird-friendly living include the prevention of light trespass and skyglow, especially from 11 p.m. to 6 a.m., March – May, and August – October. Close curtains to prevent the indoor light from escaping, and avoid blue light outdoors – choose warm white or amber lights, and shield light bulbs to direct light downward. Motion-activated light bulbs are a great way to safely light the way while cutting down on unnecessary outdoor lighting, especially since there’s no clear scientific evidence that outdoor lighting reduces crime. Excess light, on the other hand, is a crime, and light trespass is an enforceable infraction. Light pollution is harmful to humans and deadly for birds.

Logan Mayor Holly Daines signed a Proclamation to Dim the Lights for Birds at Night because reducing skyglow and light trespass saves energy and birds by reducing the often fatal disorientation caused by artificial light.

Dark Skies are filled with bright stars, so by jingles, what say we all “Dim the lights for birds at night!”

I’m Hilary Shughart with the Bridgerland Audubon Society, and I am Wild About Utah!

Credits:
Images: Milky Way above Chesler Park, Canyonlands National Park, Courtesy US National Park Service, Emily Ogden, Photographer, https://www.nps.gov/media/photo/gallery-item.htm?id=286169fc-2bab-40e0-bf8b-a13b5170aeb3&gid=2ADECB87-1DD8-B71B-0B09BD0B18C96667
Screenshot: BirdCast Migration Dashboard, Courtesy BirdCast, The Cornell Lab of Ornithology, Cornell University, https://dashboard.birdcast.info/
Featured Audio: Courtesy & Copyright © Kevin Colver, https://wildstore.wildsanctuary.com/collections/special-collections/kevin-colver
Text: Hilary Shughart, President, https://bridgerlandaudubon.org/
Additional Reading: Hilary Shughart and Lyle Bingham, https://bridgerlandaudubon.org/

Additional Reading

WildAboutUtah pieces by Hilary Shughart, https://wildaboututah.org/author/hilary-shughart/

Miller, Zach, Dark Sky Parks, Wild About Utah, Nov 2, 2020, https://wildaboututah.org/dark-sky-parks/

Leavitt, Shauna, Natural Quiet and Darkness in our National Parks, Wild About Utah, May 6, 2019 & August 3, 2020, https://wildaboututah.org/natural-quiet-and-darkness-in-our-national-parks/

Rask, Kajler, Dark Skies, Wild About Utah, Jan 1, 2018, https://wildaboututah.org/dark-skies/

Dark Skies, Bird-Friendly Living, Advocacy, Bridgerland Audubon Society, May 2022, https://bridgerlandaudubon.org/our-projects/advocacy/bird-friendly-living/dark-skies/

Dim the Lights for Birds at Night, Bridgerland Audubon Society, May 3, 2022, https://bridgerlandaudubon.org/our-projects/advocacy/bird-friendly-living/dark-skies/

International Dark Skies Association, Utah Chapter, https://utah.darksky.ngo/

Welzbacker, Hannah, Tracking a Night-Time River of Birds, Cool Green Science, The Nature Conservancy, April 13, 2021, https://blog.nature.org/science/2021/04/13/tracking-a-night-time-river-of-birds/?fbclid=IwAR18LKCQUmSlb-hHM1u4FXfVe-GqyWTwiPx91obUQbq2uB9kcPU2djlCnlk

BirdCast Dashboard, The Cornell Lab of Ornithology, Cornell University, https://dashboard.birdcast.info/

Global Bird Collision Mapper, Fatal Light Awareness Program (FLAP) Canada, https://birdmapper.org/app/

Lowe, Joe, Do Hummingbirds Migrate?, American Bird Conservancy, September 12, 2019, https://abcbirds.org/blog/do-hummingbirds-migrate/

Bobolink (Dolichonyx oryzivorus), “Bobolink is one of the few grassland-dependent species of concern that breed in Utah”, Utah Division of Wildlife Resources, April 20, 2020, https://wildlife.utah.gov/pdf/sensitive_species/birds_bobolink_2020.pdf

Bobolink (Dolichonyx oryzivorus), All About Birds, Cornell Lab of Ornithology, Cornell University, https://www.allaboutbirds.org/guide/Bobolink

Lighting, Crime and Safety, International Dark-Sky Association, https://www.darksky.org/light-pollution/lighting-crime-and-safety/#:~:text=There%20is%20no%20clear%20scientific,cost%20a%20lot%20of%20money

2022 Proclamation “Dim the Lights for Birds at Night”, https://bridgerlandaudubon.org/dim-the-lights-for-birds-at-night/

The use of the “by jingles” exclamation is in homage to Warren Dahlin’s moving Moth Radio Hour story “Open My Eyes”, in which he “makes a friend who stays with him in life and in death.” Heard on Utah Public Radio (5/28/22), The Moth, https://themoth.org/radio-hour/squeaky-wheels-1

Owens, Avalon & Cochard, Précillia & Durrant, Joanna & Farnworth, Bridgette & Perkin, Elizabeth & Seymoure, Brett. (2019). Light pollution is a driver of insect declines. Biological Conservation. 241. 108259. 10.1016/j.biocon.2019.108259. https://doi.org/10.1016/j.biocon.2019.108259

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The Great Salt Lake’s Importance for Birds

Decreasing water levels in the southern arm of the Great Salt Lake expose microbialite communities that are normally underwater. Courtesy USGS, Hannah McIlwain, Photographer
Decreasing water levels in the southern arm of the Great Salt Lake expose microbialite communities that are normally underwater.
Courtesy USGS, Hannah McIlwain, Photographer
I first met the Great Salt Lake in 1964 with two Central Michigan University college buddies on our way to Los Angeles. We heard you could float in its magical waters. Sure enough- it worked and we bobbed in its gentle waves oblivious to the many other virtues of this extraordinary water body. The Great Salt Lake’s Importance

This saltwater marvel is the largest wetland area in the American West. Its 400,000 acres of wetlands provide habitat for over 230 bird species traveling from the tip of South America, north to Canada’s Northwest Territories and as far west as Siberia. These wetlands and surrounding mudflats are vital habitat for 8-10 million individual migratory birds with many species gathering at the Lake in larger populations than anywhere else on the planet.

In 1991 the Great Salt Lake was declared a site of “hemispheric importance,” the highest level of designation given to a site by the Western Hemisphere Shorebird Reserve Network. The Reserve conserves shorebird habitat through a network of key sites across the Americas. Salt Lake receives the largest percentage of the world’s population of migrating Eared Grebes, nearly one-third of Wilson’s Phalaropes, more than half of American Avocets, and 37 percent of Black-necked Stilts. The lake’s shoreline, playas and mudflats also support 21 percent of the North American breeding population of Snowy Plovers, a species identified as one of greatest conservation needs by Utah’s Wildlife Action Plan.

These shorebirds are among nature’s most ambitious, long-distance migrants. But their numbers are dropping quickly. Shorebirds are showing the most dramatic declines among all bird groups. Species that undertake hemispheric migrations rely on specific habitats and food sources to survive, but these resources are increasingly under threat from human disturbance including habitat loss and degradation, over-harvesting, increasing predation, and climate change. As humans have continued to alter the landscape, shorebird populations continue to drop, with accelerated declines in recent decades.

Of 52 shorebird species that regularly breed in North America, 90% are predicted to experience an increase in risk of extinction. This includes 28 species already considered at high risk, and 10 imperiled species that face even greater risk.

At the base of Salt Lake’s food chain are microbialites, underwater reef-like rock mounds created by millions of microbes. These structures and their microbial mats form the base of the entire Great Salt Lake ecosystem, serving as a primary food source for brine shrimp and brine flies, which are the main food source for these aquatic birds. Falling water levels exposing the microbialites to air could trigger a collapse in the lake’s food chain according to a July study by the Utah Geological Survey.

So we humans aren’t the only one’s suffering from our disappearing Lake. Thank goodness we have awakened to this extraordinary resource found on our doorstep with many organizations and agencies attempting to save what remains for our health, wealth, and for the millions of threatened feathered friends that grace our skies, and our lives. Last May, Utah Governor Cox declared 2021 the year honoring shorebirds. We can do our part by taking action on conserving water and energy.

Jack Greene for Bridgerland Audubon Society and I’m wild about Utah and its magnificent great lake.

https://youtu.be/xv07VnQnlOY

Credits:
The Great Salt Lake’s Importance
Picture:
Audio: Courtesy & © Kevin Colver https://wildstore.wildsanctuary.com/
Text: Jack Greene, Bridgerland Audubon, https://bridgerlandaudubon.org/
Additional Reading: Lyle W Bingham, Webmaster, and Jack Greene, Author, Bridgerland Audubon, https://bridgerlandaudubon.org/

Additional Reading:

Jack Greene’s Postings on Wild About Utah, https://wildaboututah.org/author/jack/

Strand, Holly, Important Bird Areas, Wild About Utah, October 21, 2008, https://wildaboututah.org/important-bird-areas/

Strand, Holly, One of the World’s Largest Shrimp Buffets, Wild About Utah, June 3, 2008, https://wildaboututah.org/one-of-the-worlds-largest-shrimp-buffets/

Chambless, Ross, When the Great Salt Lake we know is gone, what shall we name it?, Commentary, The Salt Lake Tribune, August 19, 2021, https://www.sltrib.com/opinion/commentary/2021/08/19/ross-chambless-when-great/ [Accessed September 19, 2021]

Shorebirds are among nature’s most ambitious, long-distance migrants. Western Hemisphere Shorebird Reserve Network (WHSRN), https://whsrn.org/about-shorebirds/shorebird-status/

Drought Negatively Impacting Great Salt Lake Microbialites and Ecosystem, Utah Geological Survey (UGS), Utah Department of Natural Resources, State of Utah, July 15, 2021, https://geology.utah.gov/drought-negatively-impacting-great-salt-lake-microbialites-and-ecosystem/

Chidsey, T.C., Jr., Eby, D.E., Vanden Berg, M.D., and Sprinkel, D.A., 2021, Microbial carbonate reservoirs and analogs
from Utah: Utah Geological Survey Special Study 168, 112 p., 14 plates, 1 appendix, https://doi.org/10.34191/SS-168

Riding, Robert, Definition: Microbialites, Stromatolites, and Thrombolites, Encyclopedia of Geobiology, SpringerLink, Springer Nature Switzerland AG. Part of Springer Nature., https://link.springer.com/referenceworkentry/10.1007%2F978-1-4020-9212-1_196

Romero, Simon, Booming Utah’s Weak Link: Surging Air Pollution, The New York Times, Sept. 7, 2021, https://www.nytimes.com/2021/09/07/us/great-salt-lake-utah-air-quality.html

2015–2025 Wildlife Action Plan, Division of Wildlife Resources, Department of Natural Resources, State of Utah, July 1 2015, https://wildlife.utah.gov/discover/wildlife-action-plan.html

Governor Cox Declares 2021 as Year of the Shorebird at Great Salt Lake, Declaration celebrates 30th anniversary of Great Salt Lake as a Western Hemisphere Shorebird Reserve Network Site, Western Water News, National Audubon, May 12, 2021, https://www.audubon.org/news/governor-cox-declares-2021-year-shorebird-great-salt-lake
See also: https://wildlife.utah.gov/news/utah-wildlife-news/1182-cox-declares-2021-year-of-shorebird-great-salt-lake.html

Gov. Cox Issues Drought Executive Order, Governor.utah.gov, March 17, 2021, https://governor.utah.gov/2021/03/17/gov-cox-issues-drought-executive-order/


Written by Hall Crimmel & Dan Bedford, Filmed and Edited by Isaac Goeckeritz, iUtah EPSCor, Rachel Carsen Center Environment & Society,
Based on the book Desert Water; The Future of Utah’s Water Resources edited by Hall Crimmel and published by University of Utah Press, 2014

Carney, Stephanie, Vanden Berg, Michael D., GeoSights: Microbialites of Bridger Bay, Antelope Island, Great Salt Lake, Survey Notes, Utah Geological Survey, State of Utah, January 1, 2022, https://geology.utah.gov/map-pub/survey-notes/geosights/geosights-microbialites-of-bridger-bay-antelope-island-great-salt-lake/

Salt Lake Brine Shrimp, https://saltlakebrineshrimp.com/harvest/

Williams, Terry tempest, Opinion, I Am Haunted by What I Have Seen at Great Salt Lake, The New York Times,, March 25, 2023, https://www.nytimes.com/2023/03/25/opinion/great-salt-lake-drought-utah-climate-change.html

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Autumn Migrations

Autumn Migrations: Redhead Ducks Courtesy US FWS Nate Rathbun, Photographer
Redhead Ducks
Courtesy US FWS
Nate Rathbun, Photographer
Here comes Autumn, especially noticed in the northern parts of Utah: the colors, the cool air, the absence of many insects, the falling leaves, and the occasional dusting of snow in the mountains.

In these weather-changing conditions, wildlife species have four options: adapt to colder weather, migrate to better conditions, hibernate…or die. Today, we’ll consider migration.

As recorded by the National Geographic Society, Entomology Professor Emeritus, Hugh Dingle, mentions five basic characteristics of migration:

Prolonged movements that carry animals outside familiar habitats.

  1. They tend to be linear, not zig-zag patterns.
  2. They involve special behaviors of preparation and arrival (such as overfeeding).
  3. They demand special allocations of energy.
  4. They maintain attention to the greater mission. Meaning they are undistracted by temptations, and undeterred by challenges, that would turn other animals aside.
  5. They feel they can eat, rest, or mate later.

The entire migration movement involves body shape, physical processes, and genetics of each species.

For ten years, scientists have been documenting one of the largest aerial mass migrations on earth. According to Science Magazine, three and one half trillion insects were recorded on radar traveling from southern England to Africa and back. They represented 3,200 tons of biomass (living tissues), which was more than seven times that of the thirty million songbirds that make that same annual flight.

Movements don’t have to be monumental to be considered migratory. For instance, some consider the daily changes in depth of ocean zooplankton to be a form of migration. They spend the day near the surface benefiting from the food provided by sunlight, then sink to darker depths at night to hide.

Some rattlesnakes in Western Canada are also considered migratory as they have been tracked to relocate anywhere from 5 to 33 miles each year. This movement is spurred by cold temperatures which reduce food, and a scarcity of good den sites below the earth’s surface, which must be warm enough and at times capable of holding up to 1,000 snakes. In contrast, Arizona rattlers travel far less because they don’t require that need.

Pronghorns, which are not really antelopes, travel far and fast, around 60 miles per hour. One group travels hundreds of miles from north-central Montana up into Alberta for breeding in the Spring. Another group of nearly 20,000 goes from Grand Teton National park south to the sagebrush plains near Pinedale, Wyoming for the winter. The routes of both groups do not vary, which can be hazardous if they are blocked by snows.

Biodiversity of ecosystems and processes, which enable each species to survive, is critical. But Conservation scientists also try to preserve migrational behaviors.

Monarchs in Mexico Courtesy FWS Pablo Leutaud, Photographer Licensed under Creative Commons
Monarchs in Mexico
Courtesy FWS
Pablo Leutaud, Photographer
Licensed under Creative Commons
No doubt, there are fragile creatures which travel south to avoid cold temperatures as well as lack of food. The Monarch butterfly comes to mind. The disappearance of flowers, and freezing cold would spell doom for them in northern climates. So they embark on a 3,000 mile journey to Mexico, or southern California. Let’s consider some other long-distance, roundtrip travelers:
*Salmon and Caribou also migrate 3,000 miles.
*Dragonflies will go 10,000 miles.
*Leatherback turtles swim 12,000 miles.
*Elephant seals and Humpback whales swim over 13,000 miles.
*For birds, Northern Wheatears and Pectoral Sandpipers fly 18,000 miles.
*Sooty Shearwaters fly from the Falkland Islands to Arctic waters, a roundtrip of 40,000 miles.
*The champion distance migrant, the Arctic Tern, flies 44,000 miles from the Arctic north of Greenland to Antarctica every year!
*And the longest nonstop flight goes to the Bar-Tailed Godwit at over 7,000 miles from Alaska to New Zealand in nine consecutive days!

An entire program could also be dedicated to human migrations including various Native American tribes, the Nenets who herd reindeer 400 miles in the Russian Yamal Peninsula, and the ancient people who crossed the Bering Strait to settle in the Americas.

As we close this session of Fall migrations, consider the words of George Eliot who wrote
the following in 1841: “Delicious Autumn. My very soul is wedded to it. And if I were a bird I would fly about the earth seeking the successive Autumns.”

This is Ron Hellstern for Wild About Utah

Credits:

Images: Readhead Ducks, Courtesy US FWS, Nate Rathbun, Photographer; Monarchs in Mexico, Courtesy US FWS but licensed under Creative Commons, Pablo Leutaud, Photographer
Text:     Ron Hellstern, Cache Valley Wildlife Association

Additional Reading

https://www.fws.gov/midwest/news/monarchpopulation2016.html

https://www.fws.gov/radar/migration/index.html

https://whc.unesco.org/en/list/1290

https://blog.nature.org/science/2014/02/26/cornfield-monarch-butterfly-decline-pollinators-agriculture/

https://www.nationalgeographic.org/news/snake-migration/

https://news.nationalgeographic.com/news/2006/08/060808-bird-migration.html

NRCS Working Lands for Monarch Butterflies, https://arcg.is/0TjueO

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Why Some Birds Flock in the Vee Formation

Why Some Birds Flock in the Vee Formation: Canada Geese Flying in a V Formation. Courtesy & Copyright, Brenda Bott, Photographer
Canada Geese Flying in
a V Formation
Courtesy & Copyright © Brenda Bott, Photographer
Spring is that magical season when avian migrants return north from more balmy climates. Utah’s migrants range from ponderous pelicans to tiny hummingbirds, honking geese to crying curlews. Many arrive as they departed, in flocks.Why Some Birds Flock in the Vee Formation

Kevin Colver: Songbirds of Yellowstone, Canada Goose)

But why fly in a flock at all? One reason is predator evasion, the same reason that minnows school and elk, bison and deer bunch in herds. Embedded in a swirling mass of birds called a swarm flock, an individual bird is less likely to be picked off by an aerial predator, such as a falcon or a Cooper’s Hawk. A raptor diving into a swarm flock risks collision and injury. Targeting a bird in a swirling group is visually difficult too. Flying in a flock gains safety, but at what cost? Pigeons flying in a swarm flock take shallower, more frequent wing strokes than a solo bird. Faster wing beats probably provide more control to better negotiate turbulent aerial traffic, but extra flapping costs more in energy.

In contrast, pelicans and other big birds often fly in tidy formation flocks. Flying in a vee formation, a trailing pelican’s heart beats 13% slower than the lead bird. That’s because a trailing pelican flaps less than the leader. Unlike pigeons, then, a pelican flying in a formation flock uses less energy, not more. Big birds with slow wing beats share aerodynamic attributes with airplanes. Some of the air under their wings swirls out from under the tips, creating a spiraling vortex that trails the wing tip. Flying in a tight vee formation, each trailing bird gets a bit of lift from the upwash created by that vortex, and so it can flap a little less and glide a little more. Lead birds tire more quickly, so leaders change periodically. Leaders lose their zip, not their way. In a vee, birds also have their flock mates in good view, which is needed for the tight precision of a formation flock.

(Kevin Colver: Songbirds of Yellowstone, Sandhill Crane)

Pelicans, swans, geese, cranes, ibis, ducks, godwits, they all ply the Utah sky in formation flocks. They may be bird-brained, but our bigger migrants know a thing or two about aerodynamics.

Credits:
Images: Courtesy & Copyright Brenda Bott, Photographer
Text: Jim Cane, Bridgerland Audubon Society https://www.bridgerlandaudubon.org

Video:

Spectacular flock (called a “murmuration”) of starlings, Sophie Windsor Clive & Liberty Smith, https://www.youtube.com/watch?v=iRNqhi2ka9k As viewed from Islandsandrivers.com. Contains advertisements.

Van Ijken, Jan, Flight of the Starlings, National Geographic, Nov 15, 2016, https://youtu.be/V4f_1_r80RY
See also https://www.janvanijken.com/film-projects/the-art-of-flying/theartofflyingfullversion/

Additional Reading:

Avian flight by John J. Videler. 2005. New York, Oxford University Press. 258 pp.
Contents:

  • Acquisition of knowledge
  • The flight apparatus
  • Feathers for flight
  • Aerodynamics
  • Evolution of bird flight
  • Bird flight modes
  • The bird flight engine
  • Energy required for flight
  • Comparing the metabolic costs of flight

Usherwood JR, Stavrou M, Lowe JC, Roskilly K, Wilson AM. 2011. Flying in a flock comes at a cost in pigeons. Nature. 2011 Jun 22;474(7352):494-7. https://www.researchgate.net/publication/51242928_Flying_in_a_flock_comes_at_a_cost_in_pigeons

Weimerskirch H; Martin J; Clerquin Y; Alexandre P; Jiraskova S. 2001. Energy saving in flight formation. Nature. 413: 697-698. https://eol.org/data_objects/16885552