Notes from the Field: Spiders Abound at Trail Cameras near the Huachuca Mountains

Checking the cameras in the Border Wildlife Study is always full of wildlife sightings and interesting plants. But when I checked a block of cameras in the Huachuca Mountain foothills last Monday, there was a particular emphasis on spiders!

Spider #1:

While hiking to one of the cameras in the native grasslands of the valley, I came across a peculiar plant. There were many wildflowers blooming out there, but none were as unique as this one.

It wasn’t until I got home to look it up that I discovered it’s name: spider milkweed (Asclepias asperula).

Spider milkweed (Asclepias asperula). Credit: Meagan Bethel


Spider milkweed is a native annual that grows in open, dry spots with full sun. These plants bloom in the spring and have small green, white, and maroon flowers. Like all milkweeds, they are important food source for butterfly caterpillars and are sought out by monarch and queen butterflies.  

Another common name for spider milkweed is antelope horn, which seems very appropriate for the San Rafael Valley! 

Spider #2:

After admiring the flowers, the camera checking continued, and then I came across the second spider of the day.

This time it was the real thing!

The giant crab spider (Olios giganteus) lives in the bark of trees and shrubs and love the metal security camera boxes we strap to their trees. A new home just for them.

Giant crab spider (Olios giganteus). Credit: Meagan Bethel


If you check cameras in the Sky Islands for any length of time, you’ll become intimately familiar with these large but harmless spiders. While they can bite, they are not dangerous to humans, and I have never seen these spiders be aggressive.

Normally they stay stock-still and act like they don’t exist until you put the camera back. If you come across one while checking a camera, just be respectful: don’t bother them and they won’t bother you. But one piece of advice, don’t blindly stick your fingers behind a camera while removing it from the box!  

That field day was full of spider goodness, learning something new and seeing an old favorite. Going out in the field is always exciting. 

References:, Asclepias asperula – Spider Milkweed  

Orkin: Spider Facts 

Southwest Monarch Study: Importance of Milkweed