I presented artwork studies for bumble bees at each of the seven sites inside the exact same about three census periods even as we counted flowery resource variety (twenty eight Will get in order to eight June, 22-30 Summer, 22-31 July). For every single of one’s about three bumble-bee studies, i went to for each webpages 3 x, once during each of three-time symptoms (0800-1100, 1100-1300, 1300-1700 occasions). The sampling are accomplished toward bright months which have temperature anywhere between 19 and you can thirty two°C.
We trapped and you will designated each bumble bee which have a tiny dot off coloured modification liquid on thorax to cease relying some body over and over again while in the a sample several months during the an online site. I submitted bumble-bee variety, caste, in addition to plant varieties on which brand new bumble bee is actually found foraging and you may put out brand new bee. I spent 29 min for every single go to at the two internet having an area of ?dos,000 meters 2 , forty-five min from the a couple of 10,000-meters dos web sites, 90 min from the two 31,000-yards 2 internet sites, and you may 120 min within several 70,000-m dos sites. I examined having a sampling day prejudice playing with rarefaction (come across Mathematical Research)parisons out-of wealth off bees trapped hourly in order to financial support philosophy otherwise environment types eliminated possible testing day biases.
I recognized bumble bees worldwide playing with Mitchell (1962) since a first authority; to have meanings out-of regional varieties, we put Medler and you may Carney (1963). Hendrix at the University out-of slatke sitne sitnice Turski Еѕene Iowa. The brand new bush varieties were afterwards categorized as indigenous or produced to help you learn perhaps the bumble bees, being native, showed preferences having indigenous blooming variety.
Analytical Analyses.
We used the log2 Shannon-Wiener index to calculate bumble bee species diversity using cumulative abundances across all censuses. We also used cumulative abundances of ramets of plant species visited by bumble bees to obtain seasonal totals of available floral resources for each site. Plants included on the list were those from which we captured bumble bees in this and related studies (C. Gienapp, unpublished data). Only rarely did a plant species appear in more than one census, and therefore it is unlikely that the same ramets were counted twice in seasonal abundance measures. We examined plant diversity using the Simpson index rather than the Shannon-Wiener index because the former is less sensitive to rare plant species. These rare species are unlikely to have a strong effect on bumble bee diversity and abundance.
We recognized potential predictors out-of bumble-bee variety and you can variety for every time playing with original simple regression analyses evaluating all of them against the percentage and you will LRI of each and every private and combined surroundings varying ( Table dos) at the both five-hundred- and 700-meters radii and webpages parameters (wealth, diversity, and occurrence of bumble bee-went along to flowering ramets). Landscaping predictors showing relevance, and that chosen for additional analyses was indeed LRI of landscape from the five-hundred and you will 700 yards (having and you may without having any webpages) and part of shared grasslands about landscaping ( Dining table 2). We decided to play with LRI viewpoints that have and without having any site included to examine the fresh new cousin contributions out of floral types of the land and you may webpages itself in order to variety and you will wealth and the outcome of land and you will webpages mutual. Tall webpages predictors was Simpson range, wealth, and you can occurrence away from blooming ramets regarding bush kinds went along to from the bumble bees.
Discount specimens regarding bumble bees are in brand new distinct Stephen D
We put Pearson product-second correlation analyses to look at to own collinearity between potential predictors out-of bumble-bee diversity and you may wealth hourly just before multiple regression studies. Assortment, variety, and density away from blooming ramets in the web site were not correlated to the LRI of the landscape (having and without having any webpages integrated) within five hundred- or 700-yards radii (every roentgen 0.16). However, you will find poor collinearity involving the website functions out-of occurrence and you may abundance out of blooming ramets off kinds utilized by bumble bees (roentgen = 0.668, P = 0.07), and just one among these two local tips off resources was used in virtually any regression design. In every habits, we only use predicators appearing zero collinearity (P > 0.10).