Incidence of Large Wood Borers in the Conservation of dehesa Islands Forests in Southwestern Spain

The dehesa is a traditional agrosilvopastoral ecosystem characterized by savanna-like structure. It has been in decline since the middle of last century, particular agricultural environments where it relegated to isolated forests. This paper presents study into reduction over past 50 years. One main causes this identified as xylophagous insects, specifically wood borer Cerambyx welensii Kuster (Coleoptera: Cerambycidae). Based on estimations both population size, using Jolly Seber models, and level tree injury, single-index model, investigates role insect played dehesa. Surface area loss was found be greater than 50%, while canopy cover diminished linearly period studied, with risk disappearance woodland increasing same magnitude density. highest densities observed corresponded stands an average 1.68% year, indicating completely losing forest short term (10–30 years). proposed injury index successful categorizing size population, seems useful indicator for describing relationship between two variables. According indicator, woodlands more 10% trees severe or very injuries are at risk. Follow-up work should undertaken investigate long-term demographic changes populations, management practices developed reduce minimize preserve these relict oak unconnected landscapes.