Cryptotermes brevis - a silent earthquake for the wood structures in a World Heritage city in the Azores Islands
IRG/WP 16-50316
O Guerreiro, P A V Borges, L Nunes
In the Azores archipelago the exotic drywood termite Cryptotermes brevis, detected in early 2000’s, is destroying the wood structures of the typical buildings and is already considered the main urban pest in these islands. This work aims to show the spread evolution of this pest along the last six years in the first Portuguese city classified as world heritage by UNESCO, Angra do Heroísmo. For six years, several buildings were monitored, using traps with glue to catch the alates (flying individuals), during the swarm season that occurs, normally, from the late spring until the end of summer. The number of captured individuals was used to determine the density per building. This data was analysed with a GIS in order to build risk maps of the termite spread in space along time. The results clearly indicate that the pest species is expanding. The city centre is no longer the only affected area. The percentage of buildings that are affected or in risk to be affected is very high in the entire city. Traditional construction, with timber load bearing structures, is being replaced by metal or other materials. There is still no Integrated Urban Pest Management implemented in the region or in the city. Therefore, with time, timber structures might become restricted to exist only in buildings like museums, churches or palaces.
Keywords: Cryptotermes brevis, world heritage, Azores Islands, Integrate Urban Pest Management