A group of friends gathered in the Sonoran Desert over Easter weekend 2013 to celebrate a 40th birthday. The company, food, and chocolate cake were outstanding. The weather was perfect, and to our delight we also were surrounded by beautiful desert wildflowers, found a desert tortoise just emerging from its burrow, and climbed a hill to find a furious flurry of hundreds of spring butterflies "hilltopping."

Hilltopping is mate-locating behavior. Males compete for the best location on the highest hills, patrolling furiously, trying to find the few females amidst a sea of males. Theory is that the "top" males that can ascend the hill and hold the best territory make the best mates.

We observed black swallowtails, desert orange-tips, Sara orange-tips, possible Texas crescents, and perhaps 4 other species.

The experience was pure magic—our blood pressure plummeted and we sat, entranced, surrounded by an aerial dance, exclaiming with delight like children at a circus.

Enjoy a short video here:



Sonoran Desert spring butterfly hilltopping from ConserVentures on Vimeo.