Pollinator Post 5/9/23

Taking a walk in a leafy neighborhood in Berkeley, I come across this male Foothill Carpenter Bee, Xylocopa tabaniformis ssp. orpifex (family Apidae) perched on a flower of Roseleaf Sage, Salvia involucrata. There are five large bushes of this plant on the curbside, and several large bees are buzzing around them.

This male Foothill Carpenter Bee is stealing nectar through the back door! Too large to enter the sage flower through the front entrance, the bee has cut a slit at the base of the flower and is extracting the nectar directly. Since he is bypassing all the flower’s reproductive structures, he is not contributing to pollination. Carpenter Bees are notorious for this behavior, known as “nectar robbing”. This occurs most commonly on narrow, tubular flowers such as Salvia and Penstemon. These bees are huge and fun to watch – you can’t miss them!

This male Foothill Carpenter Bee has inserted his tongue into the nectary through the hole he has cut in the corolla right above the calyx. Note his yellow facial marking, and pale hairs on his thorax.

A female of the same species is engaging in the same behavior. Note that she is all black and lacks the yellow markings on the face.

Hey, a secondary nectar thief! Taking advantage of the hole previously cut by the Carpenter Bee on the Salvia flower this Honey Bee, Apis mellifera is enjoying a free lunch. It’s a feast for all!
