Abstract Detail

Ecology

Chmielewski, Matthew [1], Eppley, Sarah [2].

Bryophytes on the Wing: First Evidence of Widespread Bryophyte Spore Vectoring on Bird Surfaces.

Little attention has been given to animals as potential vectors for bryophyte dispersal, despite experimental evidence that spore dispersal via air is often highly leptokurtic. The few studies addressing this phenomenon have focused on mammals or invertebrates mainly dispersing fragments of gametophytic tissue at the local level. Long distance dispersal by birds has been speculated, but the incidence of moss spore epizoochory has not been explicitly addressed. Given the close association of birds with mosses as nesting material as well as a reservoir of invertebrate food items, birds frequently come into contact with sporophytes that are actively releasing spores, many of which may adhere to the surface of bird feet and feathers. Avian behavior has the potential to vastly impact the ecological community composition of bryoflora at local and regional scales. Animal, and particularly avian dispersers are considered important vectors of seed plants due to their high vagility and preference for particular habitat locales. I hypothesized that bird surfaces would regularly harbor bryophyte spores, that these spores would belong to a variety of bryophyte taxa, be viable, and would be present across a variety of bird species. In addition, I hypothesized that prevalence of bryophyte spores would depend on avian behavioral group, with vector likelihood being dependent on ecological role rather than taxonomic similarity. Passerine birds were captured via mist nets in the Wind River Experimental Forest in Gifford Pinchot National Forest, WA. I topically sampled the legs, feet, and rectrices of each bird using cotton swabs. The number of spores from each sample were determined via microscopy before being germinated on nutrient agar plates. Bryophyte species were identified by PCR amplification and Sanger sequencing of the trnL region of the chloroplast genome. Abundance and species composition of spores were determined for each bird species, and comparisons made between birds with different ecological roles. These data provide the first evidence of the potential widespread avian-mediated dispersal of bryophytes. Given the influential role of birds on the dispersal of tracheophytes, this newly described relationship has the potential to fundamentally improve our understanding of how bryophyte communities are formed and maintained. This also provides an independent system in which the theories regarding the importance of vectors and modes of dispersal that have been developed in seed plants can be tested. Finally, understanding this relationship may enhance our ability to better project the development of epiphytic community recolonization in managed forested landscapes.

1 - Portland State University, Biology, 1719 SW 10th Avenue, SRTC rm 246, Portland, OR, 97201, USA
2 - Portland State University, Biology, 1719 SW 10th Avenue, SRTC rm 246, Portland, OR, 97201, United States

Keywords:
dispersal mechanisms
community ecology
Bryophyte.

Presentation Type: Oral Paper
Session: 25, Ecology Section: Seed Ecophysiology
Location: 104/Savannah International Trade and Convention Center
Date: Tuesday, August 2nd, 2016
Time: 10:30 AM
Number: 25002
Abstract ID:510
Candidate for Awards:Ecological Section Best Graduate Student Paper