PREDATOR, PREY, AND A PLANT: ARE CARPENTER BEES (XYLOCOPA CALIFORNICA) THAT PLACE THEIR NESTS LOWER IN SOTOL (DASYLIRION WHEELERI) INFLORESCENCE STALKS BETTER PROTECTED FROM WOODPECKERS?

Desert carpenter bees (Xylocopa californica) build nests in dried inflorescence stalks of several plant species, including sotol (Dasylirion wheeleri), in southeastern Arizona. Sotol inflorescence stalks grow out of a dense rosette of barbed leaves. We asked whether nesting deeper in this rosette better protects carpenter bee larvae from woodpeckers. We recorded carpenter bee nest entrance height, the locations of bird predation marks, and the height of the tallest points of sotol leaf rosettes. Carpenter bee nests were found more often in areas protected by sotol leaves. Evidence of predation also occurred significantly more often in these protected regions. However, nests that escaped predation were placed deeper within the protection of the leaves. Our results are consistent with the hypothesis that sotol leaves may provide carpenter bee nests with protection from woodpeckers.