California Yellowjacket at Water Dish - Vespula sulphurea

Worker vs. queen

I contacted Bob Jacobson via e-mail to ask for his opinion on this image and he was generous enough to share the following comments with me:

"Many species of Vespula can be tricky to sex from photos if there is no scale, but I will do my best! Color patterns (such as those shown in the drawings adapted from Miller's publication) are variable in most of the species including V. sulphurea, so it is possible to find workers resembling the drawing of the queen and vice versa. To make it more complicated, intermediate females are sometimes encountered!

...the insect in #340753 is either a worker or an intermediate. The markings on T-1 are smoother than the first specimen [shown in this post] but still more developed than on most workers. The propodeal spots are somewhat reduced as is typical of queens. The relatively late collection date (July 26) is unlikely for a spring queen, or at least one would expect to see frayed wings by this time. I suspect it is a bit early for a fall queen, but I'm not certain how early they might start to appear at that location although one would not expect to see a fall queen foraging. An engorged worker might have a gaster distended and translucent like this."

[My most sincere thanks to Bob for his time and input on this matter.]

… Harsi S. Parker, 8 October, 2009 - 9:22pm

Carrying water...

Looks like her abdomen is pretty distended meaning she is doing more than just taking a drink. she is either using it to cool the nest or soften the soil to make excavation of the burrow easier

Did you follow her?

… Vespula vulgaris, 8 October, 2009 - 6:17pm

Nope, I didn't follow her...

...and there was at least one other female tanking up at the same water dish too. I would very much like to be able to locate one of their nests, so with future observations I will make a definite attempt to see where they head after leaving the water source. Thanks for the interesting comment!

… Harsi S. Parker, 8 October, 2009 - 9:06pm

This species must consider your area

one of the good residences. Nice photo, and I agree this is a worker.

… Hartmut Wisch, 6 October, 2009 - 7:18pm

Finding species on my property...

...that seem to be few in number or who's population has dwindled (as with C. novemnotata) always makes me so very happy! Thanks for the confirmation of my suspicions regarding the abdominal pattern on this one.

… Harsi S. Parker, 6 October, 2009 - 8:14pm