Sycamore Canyon

Last weekend I organized an insect-hunting trip to Sycamore Canyon. This canyon is along the US-Mexico border, east of Nogales in the Pajarita Mountains Wilderness. These mountains are part of the larger Tumacacori Highlands, which need protection as a wilderness!! The area is extremely diverse, and it is the only place in the United States where many subtropical plants and animals can be found. There have been occasional jaguar sightings.



We planned to hike about halfway down the canyon, but there were so many fabulous insects, plants, fungi, and amphibians that we didn’t make it very far. We turned around when ominous clouds began to rumble.



There were so many wonderful things in the canyon that I’ll need to break my report into multiple installments. I will start with caterpillars, which were abundant in all sorts of crazy shapes, sizes, forms, and colors.
Caterpillars are not my forte, so I will leave these unidentified except to say that the fuzzy ones are probably in the family Arctiidae.












Adult butterflies were also tremendously abundant, and huge clouds of orange and yellow sulfurs lifted off around us as we walked. The butterflies clustered around damp patches on the path, looking like piles of yellow leaves.



If you look carefully, you can see that the butterflies have extended their probosces to suck liquid from the mud.



This mud-sipping behavior, called puddling, provides the butterflies with much-needed nutrients and salts to supplement their nectar diet.

Backyard Ants

I realize that although my primary research interest is ants, I have yet to write about them here. Today I thought I'd start close to home and write a little about the ants in my backyard.
On Wednesday I watched several small colonies of Solenopsis aurea, a native fire ant, in my flower bed. They were preparing for a mating flight in response to the heavy rains.



The female alates (winged reproductive ants) climbed carefully up a dry piece of grass, preparing for takeoff. In the photo above you can also see a medium-sized worker, who has follwed them up.



As the twig became more crowded, the alates at the end either took off or were knocked to the ground, forced to start the arduous journey up the twig again.



A large colony of a second species of ant, Forelius pruinosus, dwells under our brick patio. They are small, fast ants that can be quite active at high temperatures. Out of curiosity, I mapped their foraging trails across the backyard. This is the result:



The nest has multiple exits, all located in the area of greatest trail density. The ant highways are anything but random- one takes the most direct route to the garbage can, a second leads to a wheelbarrow full of yard debris and compost, and a third heads to a flower bed.

I leave you with one last picture of a very beautiful and cryptic grasshopper on my mallow plant. True, it's not an ant, but it's nice anyway.