Evaluating nest supplementation as a recovery strategy for the endangered rodents of the Florida Keys

Abstract

The Key Largo woodrat (Neotoma floridana smalli) and Key Largo cotton mouse (Peromyscus gossypinus allapaticola) are federally endangered subspecies endemic to the tropical hardwood hammocks of Key Largo, Florida. Woodrats are considered generalists in habitat and diet, yet a steady decline in natural stick nests and capture rates over the past several decades suggests that they are limited by the availability of nesting habitat due to habitat loss and fragmentation. The more specialized Key Largo cotton mouse appears to rely on old growth hammock, a habitat type that is rare following past land clearing. In 2004, the U.S. Fish and Wildlife Service started building supplemental nest structures to restore habitat quality and connectivity for these endangered rodents, but nest use requires evaluation. We used camera traps and occupancy models to evaluate the factors influencing woodrat and cotton mouse use of the supplemental nests. We detected woodrats at 65 and cotton mice at 175 of 284 sampled nest structures, with co‐occurrence at 38 nests. Woodrat nest use followed a gradient from low nest use in the north to high nest use in the south, which might relate to the proximity of free‐ranging domestic cat (Felis catus) colonies in residential developments. Cotton mouse nest use, however, was related positively to mature hammock and related negatively to disturbed areas (e.g. scarified lands). The two species occurred independently of each other. Stick‐stacking behavior was observed at supplemental nests and, although it was correlated with detection of woodrats, it was not a strong predictor of their occurrence. We suggest that nest supplementation can be an important tool for species recovery as habitat quality continues to improve with succession.

Cat Gets Its Tern: A Case Study of Predation on a Threatened Coastal Seabird

“…With regard to semi-feral cats, some Australians and citizens of other countries, such as the USA, support or practice trap-neuter-release (TNR), in which semi-feral cats are trapped, desexed, and then returned to the environment as a humane response to cat overpopulation [21,72,73]. There is, nevertheless, concern and evidence that TNR cats are detrimental to wildlife populations in the USA [74]. The severe depredations caused by a single semi-feral cat in the current study are a further clear example of the consequences for wildlife management that can result if such practices are adopted widely because desexed cats still hunt post-release [67,75], as was the case for the desexed, free-roaming cat in this study.…”

Bacterial communities in the natural and supplemental nests of an endangered ecosystem engineer

“…The Key Largo woodrat is a federally endangered subspecies endemic to Key Largo, Florida (US Department of the Interior 1984). Once ranging throughout the tropical hardwood hammock, historical habitat loss and land alterations during the agricultural era have limited their distribution to North Key Largo and reduced the availability of natural nesting substrate in the environment (Winchester et al 2009, Cove et al 2017). This loss of habitat and nesting sites has been detrimental to the survival of these ecosystem engineers, as they build substantial stick‐nests by layering forest debris at the bases of trees (Fig.…”

“…Additionally, recent evidence suggests that woodrat distributions have been further limited by the presence of feral and free‐ranging cats ( Felis catus )—resulting in a shift away from their natural stick‐nest building behavior (Cove et al 2019). Once estimated to number fewer than 100 individuals (McCleery et al 2005), Key Largo woodrats have benefitted greatly from conservation management practices, including nest supplementation and exotic predator removal (Cove et al 2019), and there are now more than 2000 supplemental Key Largo woodrat nests located in their protected habitats (Cove et al 2017). These nests are constructed from large plastic culvert pipes and covered with rocks or chunks of fossilized coral (Cove et al 2017).…”

Home decorating by an endangered ecosystem engineer

“…Surveys conducted as recently as 2008 suggested the behavior had largely disappeared, but “stick stacking” reappeared around the same time as recent establishment of supplemental nests (Cove et al . ) and predator removal efforts (eg domestic cats).…”