Invasive rodent responses to experimental and natural hurricanes with implications for global climate change

Hurricanes cause dramatic changes to forests by opening the canopy and depositing debris onto forest floor. How invasive rodent populations respond hurricanes is not well understood, but shifts in abundance foraging may result from scarce fruit seed resources that follow hurricanes. We conducted studies a wet tropical Puerto Rico better understand how experimental (canopy trimming experiment) natural (Hurricane Maria) hurricane effects alter of rodents (Rattus rattus [rats] Mus musculus [mice]) their behaviors. To monitor populations, we used tracking tunnels (inked baited cards inside enabling identification animal visitors' footprints) within plots (arborist trimmed 2014) reference (closed forest). assess foraging, compared removal two tree species (Guarea guidonia Prestoea acuminata) between vertebrate-excluded free-access treatments same plots, did so 3 months before 9 after Hurricane Maria (2017). Trail cameras were identify animals responsible for removal. Rat incidences generated tunnel surveys indicated rat significantly affected or Before there no mice interior, yet present closest road hurricane, invasion coincided with increased grass cover resulting open canopy. Seed Guarea across all was dominated (75%–100% rat-removed) less than Maria. However, following Maria, treatment 2014 had 3.6 times greater rats which have resulted selecting post-hurricane patches understory foraging. Invasive are resistant disturbance this forest. Predictions frequency expected climate change should more frequent periods grassy understories mouse presence, as heightened preexisting areas disturbance.