While hiking with me today on hot, dry Mt. Diablo, Kieran spotted a fascinating sight — a pale white crab spider (Misumena vatia, perhaps) that had captured a bee at a yellow flower. The bee is much larger than the spider, but a predator is a predator. Things sometimes go the other way, too, as when wasps in the genus Pepsis, which we’ve also met on Diablo, hunt spiders much bigger than themselves!
In the past we’ve also seen a praying mantis (Mantis religiosa) that caught a bee on a bloom in Briones, along Alhambra Creek where mantises are common. It’s a good reminder that spiders and praying mantises don’t only eat harmful, pest insects. They are predators and will eat anything they can catch, even what we consider “beneficial” insects such as bees and butterflies who pollinate our crops.
We’ve often encountered crab spiders on flowers in our local parks, and even in our own terrariums at home. Some of them are tiny and wait for prey on inflorescences of grass.
It was 95 degrees on Mt. Diablo on Sunday afternoon.
Look closely, on that flower — a spider has captured a bee!
Crab spiders — this one could be Misumena vatia or Misumenoides formosipes — wait on flowers for flying insects to land.
The bee is much larger than the spider that caught it.
Steven E. F. Brown 