Do birds disperse mosses? Evidence of endozoochory in upland geese Chloephaga picta and white-bellied seedsnipes Attagis malouinus in sub-Antarctic Chile

• Main Authors: Lazaro, Xenabeth, Mackenzie, Roy, Jimènez, Jaime
• Format: Other/Unknown Material
• Language: unknown
• Published: Authorea, Inc. 2021
• Subjects: Antarctic; Antarc*
• Online Access: http://dx.doi.org/10.22541/au.161469488.80502225/v1

Birds are known to act as potential vectors for the exogenous dispersal of bryophyte diaspores. Given the totipotency of vegetative tissue of many bryophytes, birds could also contribute to endozoochorous bryophyte dispersal. Research has shown that fecal samples of the upland goose ( Chloephaga picta ) and white-bellied seedsnipe ( Attagis malouinus ) contain bryophyte fragments. Although few fragments from bird feces have been known to regenerate, the evidence for the viability of diaspores following passage through the bird intestinal tract remains ambiguous. We evaluated the role of endozoochory in these same herbivorous and sympatric bird species in sub-Antarctic Chile. We hypothesized that fragments of bryophyte gametophytes retrieved from their feces are viable and capable of regenerating new plant tissue. Eleven feces disc samples containing undetermined moss fragments from C. picta ( N =6) and A. malouinus ( N =5) and six moss fragment samples from wild collected mosses ( Conostomum tetragonum , Syntrichia robusta , and Polytrichum strictum ) were grown ex situ in peat soil and in vitro using a agar-Gamborg medium. After 91 days, 20% of fragments from A. malouinus feces, 50% of fragments from C. picta feces, and 67% of propagules from wild mosses produced new growth. The fact that moss diaspores remained viable and can regenerate under experimental conditions following the passage through the intestinal tracts of these robust fliers and altitudinal and latitudinal migrants, suggests that sub-Antarctic birds may play a critical role in bryophyte dispersal. This relationship may have important implications in the way bryophytes disperse and colonize habitats facing climate change. Keywords: birds, bryophyte dispersal, endozoochory, mosses, sub-Antarctic