Meeting Abstract
P1.30 Saturday, Jan. 4 15:30 Comparison of bee visitation at blue and white morphs of Vitex agnus-castus in Lesvos, Greece PASCUAL, C.J.*; BOWER, C.D.; BURROWS, S.; LEVINSON, B.; POLK, T.J.; BLATZHEIM, L; GONZALEZ, V.; BARTHELL, J.F.; PETANIDOU, T.; HRANITZ, J.M.; University of Maryland, College Park; Bloomburg University of Pennsylvania; Utah State University; University of California, San Diego; Southern Nazarene University; Southwestern Oklahoma State University; University of Central Oklahoma; University of the Aegean, Mytilene, GREECE jhranitz@bloomu.edu
Distinct color morphs of Vitex agnus-castus, a flowering bush native to the Mediterranean region, have been described in the literature and were identified on the Northeast Aegean island of Lesvos. Our studies examined whether these color differences impacted bee foraging behavior among plants in a restricted area near the shoreline of Kalloni Bay. Uniformly colored bushes of V. agnus-castus were categorized as either white or blue and monitored for numbers and types of bees visiting them. Both the overall bee visitation rates and the peak visitation times differed between the two morphs (Wilke’s Lambda = 0.139, F=12.44, P=0.006). The white morphs received slightly higher visitation rates at all time intervals, although this was not significant at most sample intervals. There was a visitation time by flower interaction wherein visitation peaked on the blue morphs at 12:00 hours (F=2.534, P=0.140) and on white morphs at 14:00 hours (F=5.883, P=0.027). The frequency of visitation by members of different bee families differed between transect intervals (X2=54.451, df=9, P<0.001) and between blue and white morphs (X2=17.337, df=3, P<0.001). The results suggest, at least in the insular region where we studied them, that neither species will receive a significant gain in pollinator visitation rates. Ancillary data describing nectar quality and volume from the two inflorescence types are discussed in the context of pollinator foraging dynamics and the breeding system of V. agnus-castus.
