User:Livfambro/Salt marsh harvest mouse

Lifestyle [edit]
Survey data from Suisun Marsh found that the salt marsh harvest mouse can live up to 18 months and possibly longer. Females commonly have two litters per year. In the summer, when salinity of water and vegetation increases, the mice have a notable advantage due to their ability to drink and survive purely on salt water. This adaptation to solely survive on salt water is unknown to many researchers and cannot be investigated due to their endangerment. But, it is thought that the salt marsh harvest harvest mouse has special kidney function that allows this phenomenon. The northern species can survive purely on salt water, but prefers fresh to salt water. The southern species can survive on either, and does not display a preference. Another way to differentiate these species is based on aggression and docility. Often, the salt marsh harvest mouse is quite docile and less easily agitated than its counter species, the western harvest mouse.

Habitat[edit]
The mice depend heavily on vegetation cover, particularly pickleweed and tules (Schoenoplectus spp.). Pickleweed (Salicornia virginica) is their primary and preferred habitat, as well their main food source, but R. raviventris is found in a variety of marsh habitats, including diked and tidal wetlands. Salt marsh harvest mice are not an aggressive species; many mice live in close quarters, withstanding short durations of high population density due to seasonal flooding that restricts individuals to small patches of dry ground. They can also survive tidal or seasonal flooding due to their superior ability to swim, float and climb. In a 2019 study on the food preferences of the Salt marsh harvest mouse, it was concluded that the species has a much more flexible diet than assumed years prior. They prefer pickleweed only at specific seasonal times and showcased a strong liking for different plants that aren't native to the area and typical foods enjoyed by waterfowl.

The home range and habitat use of this species differ temporally across age and sex. Juveniles exhibit home ranges of 600–700 m2, whereas adults exhibit home ranges of 1300–1500 m2.Males and females also differ in the structural complexity of their occupied habitat during fall and summer (breeding season), but occupy the same habitat during winter and spring. While the cause is still unknown, this seasonal disparity in habitat use may be related to a reduced risk of predation and intraspecific competition in more structurally complex habitats. Furthermore, movement of R.raviventris individuals within their home ranges varies seasonally, with mean distance traveled highest in June and lowest in November.