Do fires change Rhea americana habitat use? Study in the El Palmar National Park, Argentina

THORNTON, LARA; CALFAYAN, LAURA; GÓMEZ VILLAFAÑE, ISABEL

Congreso; 2021 Northeast Natural History Conference; 2021

Eagle Hill Institute

Fire avoidance was one of the first management conservation policies of El Palmar National Park (EPNP). However, this decision may have resulted in the expansion of shrubs over the palm-tree savannas, vegetation characteristic of the protected area. Therefore, a program of prescribed fire was adopted to mimic the original natural fire regime of the zone. We hypothesize that the native Rhea americana (Greater Rhea), a flighless bird which is adapted to fire, might respond favorably to such a regime of periodic burning. The objective of this study was evaluating the effect on the habitat use of Greater Rhea resulting from a natural fire that occurred on ~1100 ha in March 2018 in PNEP. We recorded indirect signs such as footprints and feces in 16 band-transects of 400 m x 6 m located in different environments of the area afffected by the fire during 1 year before (April 2017to February 2018) and after (April 2018 to March 2019) the fire. We recorded 9 landscape variables at each sampling site.Additionally, we placed 1 camera-trap per site in 5 burned sites during 40 to 85 days in each season for a year and recorded the presence, hours of use, and behavior (feeding, resting, walking) of Greater Rhea in those areas. We analyzed the association between the occurrences of Greater Rhea with the fire event, season of the year, and the landscape characteristics by means of generalized linear mixed models. This study detected the presence of Greater Rhea in all the environments in every season of the year, mainly in the open spaces such as grasslands or palm savannas. Greater Rhea did not change their habitat use of the diverse environment within the national park after this low-severity natural fire. The burned places were immediately used by this native species for feeding, breeding, and walking along all the day. These results reinforced the idea that Greater Rhea is a grassland species adapted to fires, and these events would not affect their habitat use and daily activities in the protected area.