Some Like It Hot

Eastern Ringtails, a type of Clubtail, obelisking.

The dog days of summer are upon us, and a long stretch of sultry weather lies ahead.  It can be a challenging time for people and for wildlife, but for some, it is their chance to put on a show. 

Bouquets of Mountain Pinks

Mountain Pink close up

Mountain Pink (Zeltnera beyrichii), also called Meadow Pink, Catchfly, or Quinineweed, is an annual herb less than a foot tall and best described as a neat bouquet of small, pink flowers.  Blooming May through July, Mountain Pink sprouts up like an inverted cone 8 to 12 inches high, on hot, rocky hillsides, limestone outcrops, and along gravelly roadways.  Its leaves are threadlike and are held below the multiple 0.5 to 1.0 inch wide showy pink five-petaled blooms that provide nectar for moths, butterflies, bees, and other insects.

Woolly Ironweed

Woolly Ironweed (Vernonia lindheimeri) is a 10 to 30 inch high clumping perennial, with woolly gray stems and long, narrow leaves.  Its bright purple flowers lack true petals, but the disk flowers are arranged in showy, terminal clusters.  A well-behaved species that should be used more often in gardens and landscapes, Woolly Ironweed blooms from June to September, and prefers open hillsides, roadsides, and fields offering full sun.  It is a good nectar source for many species of butterflies during the heat of summer, and is highly deer-resistant.

Blue Dasher, a type of Skimmer, obelisking

To prevent overheating on hot, summer days, some dragonflies and damselflies assume a handstand-like position called ‘obelisking.’  They raise their abdomens until the tip points up toward the sun, which helps to minimize the surface area of their body that is exposed to solar radiation.  Both males and females of these species will raise their abdomens when the temperature is high, and lower them again if shaded. Laboratory experiments have shown that this behavior is effective in stopping or slowing the rise in their body temperature.  This method of thermoregulation is practiced by about 30 different species in the Skimmer, Clubtail, and Broadwing Damsel families.  All are considered ‘perchers’ or sit-and-wait predators that spend a considerable amount of time stationary.

A sure sign that we are in the midst of a hot summer is the sound of cicadas buzzing in the air.  For their size, cicadas make as much noise as a large animal, and can be heard up to a quarter of a mile away.  In fact, the word ‘cicada’ is a direct derivation from the Latin meaning ‘buzzer.’  Many common species of cicadas in North America are in the genus Megatibicen  and are generally called the annual or ‘dog-day’ cicadas because they emerge every year in July and August, the dog days of summer.

Resh Cicada, Megatibicen resh

Male cicadas have structures called ‘timbals’ on the sides of their abdomens, and it is with these structures that they create their buzzy songs.  Unlike grasshoppers or crickets that rub their wings or legs together to produce sound, cicadas vibrate these timbals against their hollow abdomens, which amplifies the resonance of the sounds. They can even modulate the sounds by wiggling their abdomens toward or away from the tree trunk on which they are perched.  Each species has its own distinctive sound, and they use different mating songs to attract the appropriate mate.

Even in the heat of a long Texas summer, nature is busy going about its mysterious ways, offering sights and sounds that can recalibrate our senses, and allow us to continue to appreciate all that it has to offer.

Mariposa de la Muerte

Commonly known as owlet moths, cutworms, or armyworms, moths in the Noctuidae family make up one of the largest families of Lepidoptera.  The word Noctuidae is derived from the Latin word noctua meaning ‘little owl’ and the largest moth in this family in the continental United States is the Black Witch (Ascalapha odorata).

The Black Witch moth has been known as mariposa de la muerte or ‘butterfly of death’ since the time of the Aztecs, when it was believed that they were harbingers of death.  With a wingspan of up to 6 inches, its upperside is mottled dark brown to grayish-brown with hints of iridescent purple and pink, and females, which are slightly larger and lighter in color than males, have a pale almost lavender-pink median band through both fore and hind wings.  

A Black Witch (male) attracted to our mercury vapor light

Common to abundant in the New World topics as far south as Brazil, the Black Witch flies year-round in south Florida and the Rio Grande Valley of Texas.  In June and July, summer monsoons in Mexico trigger this fabulous creature to migrate north through Texas, where it is often found roosting in garages, under eaves, or under bridges.  It has the ability to migrate great distances over bodies of open water, such as the Gulf of Mexico, and one specimen was recorded in 1903 in Leadville, Colorado, caught in a snowstorm on the Fourth of July!

Primarily nocturnal, the adult Black Witch is attracted to light and fermenting fruit.  Its larvae feed at night on a variety of cassias, acacias, ebony, mesquite, and other woody legumes, and rest during the day hidden under bark and branches.  Up to 3 inches long, its caterpillar is dark gray tinged with brown, with a pale stripe down the back and dark stripes down the sides, and it relies on this natural camouflage to make it difficult to spot.  Pupation occurs on the ground in scattered leaf litter within a fragile cocoon.  Black Witches breed year round in overlapping generations, and their adult stage is thought to last only three or four weeks.

A Black Witch (female) perched above our front door!

At first glance, this very large moth is often mistaken for a small bat hovering around a porch light, but it will eventually land and linger for several hours if undisturbed.  If this happens to you, you can only hope that the South Texas legend of the Black Witch is true, as it states, “If a Black Witch lands above your door and stays there for a while, you could win the lottery!”