Abstract Detail

Ecology

Trang, Kenneth [1], Wilson, Carol [2].

Mistletoe distributions and abundance in the forest canopy are vulnerable to climate change.

Mistletoes are branch parasites of trees and shrubs, and keystone species found world-wide that have diverse biotic interactions with seed dispersers, pollinators, and animals that use mistletoes for shelter. They also restructure ecological communities, increasing productivity and biotic diversity. Given their important roles within their communities, a better understanding of their correlations with contemporary and predicted future climates will facilitate our understanding of the challenging aerial landscapes they inhabit. Currently mistletoe occurrence is largely attributed to host preference and availability, even though most mistletoes have many host trees and generally host tree ranges are greater than those of their mistletoes. Using Australian occurrence records and climate data with statistical analyses and modeling, we investigated correlations between climatic variables and mistletoe species distribution, richness, and predicted contemporary and future habitat suitability. Distributions of Australian mistletoe revealed differences among haustorial type and in some cases also genera and showed that ancestral haustorial types were associated with mesic ancestral habitats while derived types were generally associated with drier habitats that are considered derived within Australia. We found significant correlations with a suite of climatic variables, especially but not exclusively precipitation and temperature variables. We conclude that mistletoe distributional patterns, especially when haustorium type is considered, are correlated with climate, similar to other angiosperms. Mistletoes are vulnerable to the warmer, drier climates predicted for Australia and are expected to lose suitable habitat, primarily in interior arid regions of Australia. Ranges of species currently in northeastern tropical and subtropical regions will contract further north while those in semi-arid and arid regions are predicted to mostly shift south and southwest into temperate, montane, and Mediterranean habitat types.

1 - University of California, Berkeley, Plant and Microbial Biology, 111 Koshland Hall, Berkeley, California, 94720, United States
2 - University Of California, Berkeley, UC & Jepson Herbaria, 1001 Valley Life Sciences #2465, Berkeley, CA, 94720, United States

Keywords:
mistletoes
Loranthaceae
environmental niche modeling
biogeography
climate change
Bioclim variables
plant parasite
haustorium
Australia.

Presentation Type: Poster
Number: PEC020
Abstract ID:759
Candidate for Awards:None