Conservation and management implications of the effects of wildfire on a threatened Eastern Iberian Reed Bunting (Emberiza schoeniclus witherbyi) population

Abstract

Wetland degradation worldwide has led to fragmentation and isolation of diminished populations that are now more vulnerable to disturbance. Wildfires affecting wetlands can have major impacts on vegetation structure and associated waterbird communities, but rapid recovery of the initial state of vegetation cover after fire due to fast emergent vegetation dynamism has turned prescribed fire into a recurrent management method in these systems. S'Albufera de Mallorca Natural Park (Balearic Islands, Spain) was affected in 2020 by a wildfire that impacted 25% of the wetland area, including territories of Eastern Iberian Reed Bunting Emberiza schoeniclus witherbyi, a nationally critically endangered subspecies. In this study we analysed potential effects of wildfire on the breeding population of this subspecies to determine how active fire management could contribute to its conservation. Specifically, we tested whether there were structural variations in marsh vegetation as well as changes in Eastern Iberian Reed Bunting territory distribution and spatial ecology of breeding males 3 years after the fire. There were no differences in vegetation structure between affected and unaffected areas, but there was an increased density of breeding territories and higher male home-range overlap in affected areas after burning. Home-range size was not influenced by fire but by habitat, with males established in saw sedges having larger home-ranges than those in reed beds, probably due to greater movements in safer saw sedge nesting habitats with lower food availability. Prescribed fire may be a useful and cost-effective conservation tool for Eastern Iberian Reed Bunting populations by creating heterogeneous areas of mixed reed and saw sedge as suitable habitat patches for this subspecies.