Floral traits selected by European bumblebees (Bombus) in southern lands: a comparison among species and regions

MORALES CAROLINA; CUNNINGHAM SAUL; IWASAKI JAY; GLEISER GABRIELA; STRELIN MARINA; MONTALVA JOSÉ; LORD JANICE; GARIBALDI LUCAS; ARMSTRONG JOEL; AIZEN MARCELO

Punta Arenas

Congreso; VIII Southern Connections Congress; 2016

The invasion success of introduced pollinators and subsequent impact on plant-pollinator interactionsis expected to be influenced by functional traits of both, the introduced pollinator and the floweringplants of the recipient communities. Four bumblebee species have been introduced from Europe toSouthern Hemisphere land masses for crop pollination. While the short-tongued Bombus terrestrisand B. subterraneus, and the long-tongued B. ruderatus and B. hortorum were introduced to NewZealand in the late 19th century; the former species invaded Tasmania in the 1990s. Both landmassesbelong to a region lacking native bumblebee species. During the 1980s and 1990s, B. ruderatus and B.terrestris were respectively introduced to Southern South America, a region inhabited by a single nativebumblebee species, the long-tongued Bombus dahlbomii. We explored how variation in invasion successamong bumblebee species and regions is related to functional traits of the introduced bumblebeesand of the flowering plants. These traits are in turn expected to vary among regions and plant speciesbiogeographic origin. Introduced long-tongued bumblebees showed a strong affinity for non nativeflowering plant species of Northern Hemisphere origin, both in Southern South America and New Zealand,whereas B. terrestris affinity varied among the three landmasses. We examined the role of floral functionaltraits (flower size, color, symmetry, corolla length, among others), phylogeny, and time since introductionin explaining these patterns. Our results highlight the ability of B. terrestris to use a highly diverse suite offloral resources and its potential to invade a broad range of plant communities.