Gray Hairstreak Butterfly Gardens for North America’s Gray Hairstreaks

Summary: Gray hairstreak butterfly gardens in Canada, Mexico and the United States draw attention to eco-threatened relatives of survivalist-savvy gray hairstreaks.

Gray hairstreak butterflies share preference for milkweeds (Asclepias spp.) with monarch butterflies; gray hairstreak at Raindance Ranch's improved monarch habitat, Benton County, Oregon: Tracy Robillard/NRCS Oregon, CC BY ND 2.0, via Flickr

Gray hairstreak butterfly gardens accept not only gray hairstreaks but also desert green, early Hessel’s King’s and Poling’s hairstreaks, whose declines warrant placement on Xerces Society’s Red List of Butterflies and Moths.

The Xerces Society of Portland, Oregon, brings to the attention of North Americans 60 butterflies and moths whose populations can use some help from butterfly watchers. The United States Endangered Species Act (ESA) signed into law Dec. 28, 1973, by 37th U.S. President Richard Nixon covers 24 of the threatened lepidopterans. Protection of seven of North America’s Red Listed lepidopterans draws upon Canada’s Species At Risk Act (SARA), whose Royal Assent dates back to Dec. 12, 2002.

Adaptability to and occurrence in diverse habitats explain why gray hairstreaks keep flying unscathed by grazing livestock, insecticide schedules, invasive weeds, saltwater intrusions and western wildfires.

Gray hairstreaks find it possible to hide in plain sight in such disturbed, open, weedy areas as coastal strand communities, croplands, fields, gardens and waste lots.

Butterfly watchers most often get to see gray hairstreaks when the background-blending, nickle-sized adults dart erratically but rapidly through planned and wild gray hairstreak butterfly gardens. Adult female gray hairstreaks haunt ridges while adult male gray hairstreaks tend to perch on the leaves and twigs of shrubs and trees along woody edges.

It is difficult for predatory birds, frogs, mantids, spiders, toads and wasps to tell which end is up when typically solitary gray hairstreaks perch head downward. Outward-bending bases that give hindwings three-dimensional looks join antennae-like basal tails, far thinner than those of swallowtails, and eye-like basal orange-red spots to create false heads.

Afternoon schedules and camouflage keep gray hairstreak life cycles and natural histories sustainable for 39 to 64 days in planned and wild gray hairstreak butterfly gardens.

Gray hairstreaks live 4 to 6 days as pale, tiny green eggs that preferentially are deposited singly on the flowers of cotton, mallow and strawberry plants. They may spend 21 to 28 days in larval stages as green, mauve or white side-striped brown, green, pink or red flower-, fruit-, leaf-, seed-eating caterpillars. They need 10 to 20 days as black-and-brown pupae early in the flight seasons between February and October and 4 to 5 months as overwintering chrysalises.

Adult stages occupy 4 to 10 days, sufficient time for dark-gray males to defend territories and light-gray females to deposit eggs around courting, mating and nectaring.

Gray hairstreaks prefer cotton, mallow and strawberry plants even though scientists thus far catalogue 50 different species of hostplants throughout Canada, Mexico and the United States.

Legumes qualify as high-ranking candidates for alternate hostplants since the root nodules of Fabaceae family members support nitrogen-fixing bacteria whose activity solubilizes insoluble nitrogen in soils. Egg, larval and pupal hostplants in planned and wild gray hairstreak butterfly gardens range from balloonvine to bean clover, cotton, hibiscus, mallow, strawberry and sweet-fern plants. Adult female and male gray hairstreak butterflies sip preferentially on the nectars of clovers, dogbanes, goldenrods, milkweeds, mints, tick trefoils, white sweet clovers and winter cresses.

It turns out that hairstreak butterfly gardening for one hairstreak species in Canada, Mexico and the United States welcomes all of North America’s hairstreak butterfly species.

dorsal (underside) and ventral (upperside) views of gray hairstreak butterfly's (Strymon melinus) wings: TRCA Restoration @TRCA_Restore via Twitter Aug. 14, 2012

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

gray hairstreak: Tracy Robillard/NRCS Oregon, CC BY ND 2.0, via Flickr @ https://www.flickr.com/photos/nrcs_oregon/19996247089/

dorsal (underside) and ventral (upperside) views of gray hairstreak butterfly's (Strymon melinus) wings: TRCA Restoration‏ @TRCA_Restore via Twitter Aug. 14, 2012, @ https://twitter.com/TRCA_Restore/status/235454975294189569

For further information:

Las Pilitas Nursery. 21 October 2008. "Gray Hairstreak." YouTube.
Available @ https://www.youtube.com/watch?v=uHRk_dHbR-w

“Red List of Butterflies and Moths.” Xerces Society for Invertebrate Conservation > Programs > Endangered Species.
Available @ http://www.xerces.org/red-list-of-butterflies-and-moths/

TRCA Restoration‏ @TRCA_Restore. 14 August 2012. "A Gray Hairstreak butterfly at #TommyThompsonPark! Last documented August 1999. (Pictures taken by Ann Gray)." Twitter.
Available @ https://twitter.com/TRCA_Restore/status/235454975294189569