BUMBLE BEES (GENUS BOMBUS) ARE THE SECOND MOST ECONOMICALLY PRODUCTIVE POLLINATORS IN GLOBAL AGRICULTURE, AND ARE MORE EFFICIENT POLLINATORS THAN HONEY BEES ON CROPS SUCH AS BLUEBERRIES, CRANBERRIES, AND TOMATOES. HOWEVER, THERE IS EVIDENCE THAT THEIR POPULATIONS GLOBALLY ARE IN DECLINE. IN THE US, AT LEAST SEVEN OF OUR 40 NATIVE SPECIES HAVE EXPERIENCED POPULATION DECLINES OR RANGE CONTRACTIONS IN THE LAST 4 DECADES. SOMEWHAT SURPRISINGLY, EMERGING RESEARCH SUGGESTS THAT URBAN AREAS MAY BE PLACES WHERE BEES AND OTHER POLLINATORS MAY FIND REFUGE AND THUS OFFER OPPORTUNITIES FOR CONSERVATION. IN URBAN ENVIRONMENTS POCKETS OF HIGH PLANT DIVERSITY AND LONGER GROWING SEASONS MAY GIVE BEES OPPORTUNITIES TO SURVIVE AND PERSIST THAT ARE NOT PRESENT IN MORE RURAL AND AGRICULTURAL AREAS OF THE LANDSCAPE WHERE BEES HAVE BEEN SHOWN TO BE IN DECLINE. OUR PROJECT WILL EXAMINE THE RELATIONSHIP BETWEEN FEATURES OF URBAN ENVIRONMENTS (DEGREE OF URBAN DEVELOPMENT, PLANT DIVERSITY, LENGTH OF GROWING SEASON, ETC.) ON BUMBLE BEE POPULATION SIZE, ABUNDANCE, AND PATHOGEN LOAD.WE WILL ADDRESS THIS QUESTION BY SAMPLING BEES ACROSS SOUTHERN WISCONSIN IN LOCATIONS WITH A WIDE VARIETY OF URBAN AND RURAL CHARACTERISTICS (E.G., DIFFERENT FLOWERING PLANTS, HUMAN POPULATION DENSITIES, ETC.). WE WILL COMBINE OUR BUMBLE BEE SURVEYS WITH LARGE CITIZEN-SCIENCE DATABASES OF BUMBLE BEE SIGHTINGS AND APPLY SPECIES DISTRIBUTION MODELING TO THIS DATA TO DETERMINE HOW FEATURES OF URBANIZATION AFFECT BUMBLE BEE ABUNDANCE AND SPECIES DIVERSITY. WE WILL ALSO USE POPULATION GENETICS APPROACHES TO MEASURE BUMBLE BEE COLONY SURVIVAL, COLONY DENSITY ACROSS URBAN AND RURAL AREAS. FINALLY, WE WILL COLLECT BEES AND MEASURE THEIR PATHOGEN LOADS TO UNDERSTAND IF URBAN BEES ARE HEALTHIER. ULTIMATELY, THIS DETAILED STUDY ON BUMBLE BEES WILL HELP IDENTIFY THE ASPECTS OF CITIES AND THE COUNTRYSIDE THAT MAY PROMOTE OR LIMIT BUMBLE BEE DISTRIBUTION, HEALTH, AND SURVIVAL ACROSS THE LANDSCAPE. THIS WILL GIVE US BETTER TOOLSTO POTENTIALLY MITIGATE STRESSES ON BEES IN BOTH RURAL AND URBAN ENVIRONMENTS, AND OFFERS OPPORTUNITIES FOR CONSERVATION OF THIS IMPORTANT NATIVE GROUP OF KEY POLLINATORS.