Sphinx Moths

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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.

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: http://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: http://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/hawk_moths.shtml

The Mud-Daubing Wasp

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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. http://www.amazon.com/Wasps-Howard-Evans/dp/0715360604

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

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

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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. http://scholarworks.boisestate.edu/td/505/

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

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

Red-tailed hawk. Utah Conservation Data Center. http://dwrcdc.nr.utah.gov/rsgis2/search/Display.asp?FlNm=butejama

Terrestrial gartersnake. Utah Conservation Data Center. http://dwrcdc.nr.utah.gov/rsgis2/Search/Display.asp?FlNm=thameleg

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

Wind and Sagebrush

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Mountain big sagebrush (Artemisia tridentata subsp. Vaseyana) in flower – Photo Courtesy and Copyright Dr. Leila Shultz

Three-tip sage (Artemisia tripartite) with visible yellow flowers. – Photo Courtesy and Copyright Dr. Leila Shultz

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 http://www.sagestep.org/pubs/brushguide.html.

Credits:

Photo Courtesy & Copyright 2007 Dr. Leila Shultz
Text: Stokes Nature Center: Holly Strand

Sources & Additional Reading:

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

Shultz, Leila. 2012. Pocket Guide to Sagebrush. PRBO Conservation Science. http://plants.usda.gov/java/
As pdf: http://www.sagestep.org/pubs/pubs/sagebrush_pock_guide.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):

http://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.

Owls & iPods

Audio:  mp3

Great Horned Owl and Chick
Photographer: George Gentry
US FWS Digital Library

Hi I’m Holly Strand.

In early spring, my friends and I went owling in a northern Utah canyon. We were hoping for modest success—just to see or hear a northern pygmy or great horned owl — both common owls in our area.

To better the odds we brought an iPod with prerecorded owl sounds. We played the northern pygmy call for 20-30 second intervals and listened intently in between intervals.

After 10 minutes of off-and-on playbacks we heard an answering call from a nearby conifer grove. We were ecstatic that we had made contact with an actual owl. But wait! Was it an owl we heard or just another iPod user?

Pygmy Owl
Photographer: Bob Miles
US FWS Digital Library

According to David Sibley, author of the Sibley Guide to Birds, the proliferation of digital audio devices and recorders among birders has both pluses and minuses. On the plus side, you can often entice certain birds out of hiding using playbacks. For example, if a territorial male thinks a rival bird is threatening to encroach on its territory, he may come out to confront the intruder. Or he may sing his “I’m Here, So Stay Away” song. A female bird might approach the recording source as a potential date. Using playbacks, you can target specific species to see or hear without disturbing others.

On the flip side, overuse of these playback devices can cause unnecessary stress and distraction in the target birds—and annoyance among other birders. In one study, the use of playbacks upset the avian apple cart by causing high-ranking black- capped chickadee males to lose status. The rest of the flock perceived them as losers as they were unable to drive away an unwanted phantom intruder.

Because the widespread use of recorded playbacks is relatively new, proper etiquette is still evolving. But here are some key points.

  • Keep the volume low and use only occasional snippets of sound—less than 30 seconds at a time. Leave a long pause between snippets. Definitely do not broadcast loud or continuous sound.
  • It is illegal to disturb endangered or threatened species. And these recordings can be interpreted as disturbance. So stick with sounds of non-threatened species.
  • Finally, check the rules at your birding location. The use of playback is prohibited in some parks and refuges.

For source material and websites with bird sound recordings, go to www.wildaboututah.org.

For Wild About Utah, I’m Holly Strand.

Credits:

Photos: Courtesy US FSW Digital Media Library
Text: Holly Strand

Sources & Additional Reading:

Sibley, David. 2011. The Proper Use of Playback in Birding. Sibley Guides: Identification of North American birds and trees. http://www.sibleyguides.com/2011/04/the-proper-use-of-playback-in-birding/ [Accessed May 19, 2011]

Recordings:

Soundscapes for Birders by Kevin Colver http://www.7loons.com/

http://www.xeno-canto.org/ shared bird sounds from the whole world

Beletsky, Les, editor. 2010. Bird Songs Bible: The Complete, Illustrated Reference for North American Birds Contains digital audio player.

Ipods and mp3 apps:

iBird http://www.ibirdexplorer.com

Audubon Birds Field Guide http://www.audubonguides.com/field-guides/mobile-apps.html

The Sibley eGuide to the Birds of North America http://www.mydigitalearth.com