Wild About Utah

September 11, 2014April 18, 2021

Sphinx Moths

White-lined Sphinx, Hyles lineata, Courtesy Whitney Cranshaw, Colorado State University, bugwood.org — Big Poplar Sphinx
*Pachysphinx occidentalis*
Courtesy Whitney Cranshaw
Colorado State University
bugwood.org

White-lined Sphinx
*Hyles lineata*
Courtesy Whitney Cranshaw
Colorado State University
bugwood.org

White-lined Sphinx Caterpillar
*Hyles lineata*
Courtesy Whitney Cranshaw
Colorado State University
bugwood.org

I vividly remember the first time I saw one – a small winged creature whirring from flower to flower in the evening light, its long tongue dipping for nectar within tube-shaped blooms. I was mesmerized, and struggled for a closer look.Sphinx Moths

If you’re thinking that I must have seen a hummingbird, you would be making a very common mistake. A mistake, in fact, that has given this critter one of its many nicknames. The winged wonder I saw that summer night was a sphinx moth, also called a hummingbird or hawk moth because of their large size and bird-like characteristics.

In all stages of their life, these insects are large. Caterpillars grow to a robust 4 inches in length and adult wingspans can measure more than 5 inches. Sphinx moths are also some of the fastest insects on earth and have been clocked flying at over 30 miles per hour. Their size, speed, and flying ability reflect those of the hummingbird so closely that they are commonly misidentified.

Sphinx moths are a beloved sight in many Utah gardens. However, they also hold a bit of a devious surprise. The larvae, or caterpillar, of one common species of sphinx moth are well known by vegetable gardeners. They are large and bright green with a distinctive horn near their hind end. Like the adults, these larvae go by many names, the most common being the tomato hornworm. Hornworm caterpillars, unlike their adult counterparts, are not beloved by gardeners. They are voracious beasts with the ability to strip the vegetation off a tomato or pepper plant in one day.

Aside from our garden plants, young hornworms of other species feed on a variety of vegetation including willow, poplar and cottonwood trees. Adult moths rely on a host of flowers such as columbine, honeysuckle, larkspur and evening primrose. Here in Utah you might come across one of a handful of different species in the sphinx moth family including the five-spotted hawk moth and the white-lined sphinx. Look for them in the late summer evenings as daylight begins to fade. But be sure to look twice to avoid mistaking them for something they’re not.

And the next time you find a hornworm on your tomatoes, maybe just relocate the little bugger so that you can enjoy it once metamorphosis changes the beast into a beauty.

For more information and pictures of our native sphinx moths, 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 Whitney Cranshaw, Colorado State University, Bugwood.org
Images licensed under Creative Commons Attribution 3.0 License
Text: Andrea Liberatore, Stokes Nature Center, logannature.org

Additional Reading:

Cranshaw, W.S. 2007. Hornworms and “Hummingbird” Moths. Colorado State University Fact Sheet 5.517. Found online at: https://www.ext.colostate.edu/pubs/insect/05517.pdf

Buchman, Steve. 2010. Pollinator of the Month: Hawk Moths or Sphinx Moths (Sphingidae). US Forest Service. Found online at: https://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/hawk_moths.shtml

September 4, 2014August 23, 2023

The Mud-Daubing Wasp

Female Sceliphron caementarium completing nest cell, Click to view a larger image, Courtesy and Copyright 2011 Jim Cane — Female *Sceliphron caementarium*
completing nest cell
Courtesy and
Copyright © 2011 Jim Cane

Pupa of
*Sceliphron caementarium*
Courtesy and
Copyright © 2011 Jim Cane

Pupa of Sceliphron caementarium. Click to view a larger image, Courtesy and Copyright 2011 Jim Cane — Female *Sceliphron caementarium*
completing nest cell
Courtesy and
Copyright © 2011 Jim Cane

Pupa of
*Sceliphron caementarium*
Courtesy and
Copyright © 2011 Jim Cane

The recession has slowed housing starts, but builders of clay dwellings remain busy. Millions of clay homes are built this and every summer in Utah. These dwellings can disintegrate in a summer cloudburst, so you’ll find them beneath overhangs like rock cliffs, or under bridges and the eaves of your house.

These free-standing mud homes are built by a few dozen species of solitary bees and wasps. Among them is the mud dauber, Sceliphron caementarium, a big leggy wasp found throughout Utah. The female wasp constructs hollow clay units one at a time, each the dimensions of a pitted date. The mother mud dauber gathers the wet clay in pellets. At the nest site, she draws the pellet into a ribbon of clay which becomes the next arch of the tubular nest. While working the clay, she audibly buzzes her flight muscles. This vibration visibly liquefies the clay for a few seconds. This strengthens its bond, much as workers in concrete do using large vibrating probes.

The mother wasp then collects spiders, often plucking them straight from their webs after a pitched battle. She permanently paralyzes each spider using her venomous sting. The venom is not lethal. Rather, it is paralytic, keeping the spider alive and fresh but helplessly immobile, a gruesome spider buffet for her grub-like larva to eat. Each hollow nest is packed with a half dozen spiders, one of which receives her egg. In a few weeks time, the growing wasp larva finishes eating its buffet and pupates, becoming dormant for the winter.

Nest building and provisioning by these wasps is a complex result of heritable instincts tailored to local circumstances by learning. It is also a rare trait among insects, most of whom simply lay their eggs and leave. Through observation and manipulative experiments, students of animal behavior have investigated mud-building wasps for well over a century. If you have mud daubers around your home, grab a cool drink, pull up a chair, and enjoy watching their home-making labors.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:

Images: Courtesy & Copyright Jim Cane, Bridgerland Audubon Society
Text: Jim Cane, Bridgerland Audubon Society

Additional Reading:

“The Wasps”, Evans, Howard E. and Eberhard, Mary Jane West, 1970. Ann Arbor, University of Michigan Press. 265 p. illus. https://www.amazon.com/Wasps-Howard-Evans/dp/0715360604

“Bees, wasps, and ants : the indispensable role of Hymenoptera in gardens”, Grissell, Eric. 2010, 335 p. https://www.amazon.com/Bees-Wasps-Ants-Indispensable-Hymenoptera/dp/0881929883

September 2, 2014October 5, 2022

Wildlife dispersal in late summer (Or, It’s time to leave the nest!)

Wildlife dispersal in late summer: Click to view larger image of Adult great-horned owl perched at dusk, hunting for its young, Photo Courtesy and Copyright Mark Larese-Casanova — Adult great-horned owl
perched at dusk,
hunting for its young
Photo Courtesy & Copyright 2009
Mark Larese-Casanova

Hi, this is Mark Larese-Casanova from the Utah Master Naturalist Program at Utah State University Extension.

Late summer is the time of change when the rich nature born of spring matures and enters the next stage of its life. Streams and wetlands may dry up in the heat. Wildflowers wither and produce seeds to ensure a plant’s survival into the future. And, young wildlife leave their place of birth to strike out on their own.

Prior to fledging, young red-tailed hawks build flight muscles by hopping and flapping their wings in the nest. Once they are strong enough, the young red-tailed hawks make excursions from the nest, often soaring together, calling to each other while they fly. This time of year, red-tailed hawk fledglings can still be seen perched atop telephone poles, even in the middle of town, calling to their parents and begging for food. As a bird that usually spends the entire year in Utah, the red-tailed hawk must prepare for its solitary, cold winter ahead.

The calls of great horned owls often echo through the late summer nights. The adult owl soars through an open field while the fledgling owlet is perched nearby, calling for food. The parent responds, and faithfully catches a mouse to feeds its young. Aside from their echoing calls, this all happens quietly and almost invisibly. A lucky observer might spy an owlet and its parent at dusk, but the great horned owl’s soft feathers ensure that their flight is silent, even when just overhead.

Some young reptiles disperse in summer, too, just like birds. Tiny garter snakes, no larger in length or width than a pencil, can often be found slithering across meadows or even lawns. Rather than laying eggs in a nest, the female garter snake retains the eggs in her body until they are ready to hatch. While young garter snakes receive no parental care after birth, the mother hedges her bets by producing upwards of twenty young in the second half of each summer. At least two need to survive over the mother’s life to maintain a stable population.

Fledging and dispersal in late summer is a time of great risk, though. It’s very common in Utah to see road kill of young marmots, skunks, raccoons, and mink, among others. Many inexperienced young animals are also taken by predators. In nature, survival to adulthood is relatively uncommon, so the great investment of the parents is essential for a species to survive.

For Wild About Utah, I’m Mark Larese-Casanova.

Credits:

Images: Courtesy and copyright Mark Larese-Casanova
Text: Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.

Additional Reading:

Danilson, C.D. Post-Fledging Ecology of Great Horned Owls in South Central Saskatchewan. Master’s Thesis. https://scholarworks.boisestate.edu/td/505/

Great Horned Owls. All About Birds. Cornell Lab of Ornithology. https://www.birds.cornell.edu/AllAboutBirds/owlp/ghowl

Red-tailed hawk. Hawkwatch International. https://www.hawkwatch.org/blog/item/130-red-tailed-hawk-buteo-jamaicensis

Great Horned Owl, Utah Division of Wildlife Resources, Department of Natural Resources, State of Utah, https://fieldguide.wildlife.utah.gov/?species=bubo%20virginianus

Red-tailed Hawk – Buteo jamaicensis. Utah Division of Wildlife Resources, Department of Natural Resources, State of Utah, https://fieldguide.wildlife.utah.gov/?species=buteo%20jamaicensis

Common Gartersnake – Thamnophis sirtalis. Utah Division of Wildlife Resources, Department of Natural Resources, State of Utah, https://fieldguide.wildlife.utah.gov/?species=thamnophis%20sirtalis

Black-necked Gartersnake – Thamnophis cyrtopsis. Utah Division of Wildlife Resources, Department of Natural Resources, State of Utah, https://fieldguide.wildlife.utah.gov/?species=thamnophis%20cyrtopsis

Terrestrial Gartersnake – Thamnophis elegans. Utah Division of Wildlife Resources, Department of Natural Resources, State of Utah, https://fieldguide.wildlife.utah.gov/?species=thamnophis%20elegans

Thamnophis elegans: Western Terrestrial Garter Snake. Animal Diversity Web. https://animaldiversity.ummz.umich.edu/accounts/Thamnophis_elegans/

August 21, 2014July 18, 2020

Wind and Sagebrush

Hi, I’m Holly Strand of the Quinney College of Natural Resources at Utah State University.

By late summer, most of Utah’s flowering plants have fizzled out for the year—those that remain are looking pretty spent. But not true for the sagebrush. It’s show time for over 20 types of sagebrush of the Intermountain West.

Like grasses and conifers, sagebrush plants are pollinated by the wind. They have no need for the specialized traits designed to attract live pollinators. Instead, they have evolved other strategies to survive and multiply.

For instance, wind-pollinated plants don’t need showy, colorful petals to attract insects or birds. The wind is going to do its job anyway regardless of visual cues. Thus sagebrush flowers are very small and nondescript. In fact, when passing by flowering sagebrush you might not even notice that it’s in bloom. Look for long spikes with clusters of tiny flower heads. The pale yellow flowers are concealed by petal-like bracts, which are the very same color as the rest of the plant.

While the flowers of sagebrush lack in beauty, they make up in quantity. A single flowering stem of the most common sagebrush—known simply as big sagebrush–can hold hundreds of flower heads that produce a massive amount of pollen. Most wind-blown pollen grains won’t end up anywhere near the female part of another plant. So to make up for this risky method of fertilization, individual plants must produce greater volumes of pollen. In contrast, plants with live pollinators get door to door service during fertilization. Far less pollen is needed to get the same job done.

Scent is another way for plants to attract live pollinators. Species pollinated by bees and flies have sweet scents, whereas those pollinated by beetles have strong musty, spicy, or fruity odors. However, the iconic western scent of the sagebrush has absolutely nothing to do with pollination. Instead, the pungent aroma of the sagebrush is a by-product of certain chemicals produced in the leaves. These chemicals evolved to repel animals and to reduce the odds of being eaten or grazed.

The chemicals—bitter terpenes, camphors and other secondary compounds–—peak in early spring. But as the late-summer flowering period approaches, the chemicals start to break down. By winter, browsers like deer and elk can nibble on the protein-rich seed heads without getting a nasty aftertaste.

Thanks to botanist Leila Shultz for sharing her knowledge of sagebrush. For a link to the online version of Leila’s book Pocket Guide to Sagebrush, go to www.wildaboututah.org
If you’d like a hard copy of this Pocket Guide, send an email to wildaboututah@gmail.com We have 5 copies to give away to listeners from across the state.

For Wild About Utah and the Quinney College of Natural Resources, I’m Holly Strand.

NOTE: The copies are gone. You can view the book as a .pdf here or check here for the next printing from https://www.sagestep.org/pubs/brushguide.html.

Credits:

Photo Courtesy & Copyright 2007 Dr. Leila Shultz
Text: Holly Strand, Quinney College of Natural Resources at Utah State University

Additional Reading:

Dudareva, Natalia. 2005. Why do flowers have scents? Scientific American April 18. https://www.scientificamerican.com/article/why-do-flowers-have-scent/

Shultz, Leila. 2012. Pocket Guide to Sagebrush. PRBO Conservation Science. https://digitalcommons.usu.edu/sagestep_reports/20/
As pdf: https://rdjzr2agvvkijm6n3b66365n-wpengine.netdna-ssl.com/wp-content/uploads/2018/06/sagebrush_pock_guide_reduced.pdf

Shultz, L. M. 2006. The Genus Artemisia (Asteraceae: Anthemideae). In The Flora of North America north of Mexico, vol. 19: Asterales, pp. 503–534. Flora of North America Editorial Committee, eds. Oxford University Press. New York and Oxford.

USDA, NRCS. 2012. The PLANTS Database, National Plant Data Team, United States Department of Agriculture (USDA), Natural Resource Conservation Service (NRCS): https://www.plants.usda.gov

VanBuren, R., J. C. Cooper, L. M. Shultz and K. T. Harper. 2011. Woody Plants of Utah. Utah State University Press & Univ. Colorado. 513 pp. https://upcolorado.com/utah-state-university-press/item/2323-woody-plants-of-utah