Meeting Abstract
As the only terrestrial mammal entirely restricted to coastal marshes, the salt marsh harvest mouse (Reithrodontomys raviventris) occupies an environment that is subject to tidal flooding on a daily and seasonal basis. Thus, specifically how mice endure or avoid high tides has been a subject of interest amongst salt marsh harvest mouse researchers and wildlife managers. Previous researchers have indicated that salt marsh harvest mice tend to climb onto to taller vegetation during high tides, moving vertically onto emergent vegetation rather than horizontally toward uplands away from water. As a corollary, salt marsh harvest mice tend to have relatively longer and thicker tails compared to other co-occurring species. However, the extent to which these morphological differences affect their locomotor abilities is unclear. To this end, we measured climbing-related morphology (tail and foot pad dimensions) and performance (forelimb grasping forces and climbing behavioral assays) of salt marsh harvest mice, in comparison to those of co-occurring western harvest mice and house mice. Our preliminary results suggest differences among species, primarily with regard to the salt marsh harvest mouse’s relatively more extensive use of the tail as a tactile or prehensile organ. Because natural selection acts directly on morphological and performance traits, these measurements of their abilities to move during high tides are critical for understanding and predicting the success of salt marsh harvest mouse in its dynamic wetland environment.
