Friday, July 9, 2010

Our Place at Night

In Arizona, the Monsoon season has begun. Temperatures have been hovering above the 100 mark for days and finally the humidity is also rising. Today, clouds are covering most of the sky. Although it hasn't actually rained yet, the fauna in our back yard is waking up from the stasis induced by the dry heat of June. But since it is still so hot during the day, one has to get a flash light and walk the night to see the animals.

At sunset, several species of bats flutter and zigzag like butterflies. Lesser Nighthawks Chordeiles acutipennis begin sailing across the sky.

The Nighthawk has spent the day immobile and nearly invisible, huddled down on a Palo Verde branch.

At dusk he flies at high speed sweeping insects into his wide, short beak that is surrounded by bristles that serve as sensory organs and as a catching basket.

Pack Rats rustle around their piled-up middens, Cactus Mice Peromyscus eremicus (picture) hide in the shadows, and we see Pocket Mice hopping around. These miniature versions of the Kangaroo-rat are too shy and fast for my camera, but I'll keep trying.

Another shy creature is the female Tarantula Aphonopelma sp. that excavated her burrow in our drive way. She opens the silk cover of the entrance every night to come out to hunt, but she stays close enough to her hole to slip back in as soon as my flashlight beam hits her.

The males are much less camera shy, and anyway, they don't have holes to hide in when they are wandering about hunting and looking for females.

Black Widows Latrodectus hesperus are hanging quite unafraid in their webs, presenting the red hour-glass of their under-bellies as a warning. Who would bother them? A bite can be devastating. But you won't find them during the day.

Lightning quick Sunspiders, also called Windscorpions, Solifugae rush by. Having no poison, they rely on the strength of their formidable mandibles to overpower their prey.

A female Scorpion is carrying her offspring on her back. Scorpions, like many other insectivores, are attracted to the bounty on my black-lighting sheet.

A real nuisance for the insect collector are the big Sonoran Desert Toads Bufo alvarius. They have learned to come to my black light and probably get more beetles than I. We've reached an uneasy coexistance with these amphibians that seem to emerge earlier every summer. Even our dog Cody has learned from his first nearly tragic encounter that sent him to the vet with a racing heartbeat and partial paralysis. For several years after that he was a bufotenin licking junkie: We could always tell from his swagger and fluffed-up fur when he had found the first toad of the season and was high again. But by now he leaves them alone, even when they use his water dish as a swimming pool. None of the other dogs ever bothered the toads.

As every bird bath has its toads, every porch light has its Mediterranean House Gecko Hemidactylus turcitus. This introduced species spends its life in the vertical plane of walls. Special toe pads give the Gecko a secure hold that allows him to shoot forward and snap up any moth that is drawn to the light.
I hope they also get some of the Kissing Bugs Triatoma rubida. These Reduviids grow up in Pack rat nests, but at night the adults hang around lights and are always ready for a meal of blood from our sleeping dogs.

Another Gecko hunts on the ground. The native Western Banded Gecko Coleonyx variegatus bogerti lacks the toe pads of its European cousin. His very thin, soft skin may make him more dependent on cooler, moister hide-outs. During the day I find this species under flower pots and bird baths in shady places.

With a dry rustling noise, huge Long-horned Beetles land close to lights: Palo Verde Root Borers Dreobrachus hovorei. At up to 4 inches, they are the longest, if not the heaviest Arizona Beetles.

I am expecting to find their relatives, the long-jawed Nothopleurus lobigenis any day now, too. I remember from last year that they seem to take their clue from the first actual downpour.

Sadly, this summer we are missing our Western Screech Owls Megascops kennicottii. Since we bought our house in the Tucson Mountains in 2002 we heard their dropped-ping-pong-ball call during summer nights and every year watched about four young ones emerge from a cavity in an old Ironwood tree. Last year's terrible drought seems to have been too much for them.

When the dogs start barking at night, we listen whether they are joining the choir of the coyotes, race around and bark angrily at Javelinas, or give the stationary, rhythmic bark that we have learned to associate with rattlers Crotalus atrox . These snakes become night active when the temperatures force them into shelter during the day.


  1. Wow! That reads like a catalogue of all the critters I would love to see!

  2. Laurie Larwood said:
    Your night animal pictures are wonderful. And the mesquite bug sequence answers some questions I've been wondering about these colorful little creatures. Thanks.

    Apparently I can't post comments because I'm not a member of the 5 or so selected groups--but nice work anyway.

  3. Margarethe, durchweg wieder wunderschöne Fotos, ich geniesse jedes einzelne! Text verstehe ich auch weitestgehend wenn ich mehrmals lese :-)) was ist black light?
    Hab ichs recht verstanden, Du hörst Nachts an der Art wie Dein Hund bellt ob er auf eine Schlange gestossen ist? Wow. Macht er dann einen Bogen um sie?
    Tolles Blog, ich lese viel darin weil es so eine andere Welt zeigt als ich sie kenne- ich finds sehr interessant.