Monitoring of saproxylic beetles: the more diverse the harder the work!

This summer the monitoring to asses biodiversity before the interventions was carried out. The action A1 that includes such assessment is facing the time for species identification, and data entry and organization.

Among the sampled taxonomic groups (vascular plants, lichens, birds, lichens and saproxylic fungi and beetles) the one that requires the greatest effort in the identification is represented by saproxylic beetles.

We all know that insects are the most diverse and abundant animals that share our world, and we can imagine how numerous are insect species in priority habitats as those that are the focus of FAGUS project.

Indeed in the 33 monitoring areas more 1000 specimens of insects were collected through window-traps and eclectors.

The performed trapping activity is strictly necessary for forest biodiversity sampling. These trapping techniques have a very low impact since they allow catching individuals that during their activities are intercepted by the traps by chance, as opposed to trapping systems that attract insects by volatile chemicals and that are non-selective with respect to the group of insects of interest. Indeed the trapping techniques that were used allow for a species-rich data collection through the trapping of a relatively low number of trapped individuals.

Window-flight trapping, also called flight-intercept trapping, is currently the most frequently used technique for catching flying active saproxylic beetles. Window flight traps consist of transparent verticals barrier that are invisible to the insect. On hitting the barrier, most beetles drop down and fall into a collection container with liquid preservatives.

 

The eclector trap catches beetles leaving decaying wood by means of an enclosure. Among the advantages of this method are: the strict selection of saproxylic organisms, and the fact that it does not cause any damage to deadwood and other forest microhabitats.

The great majority (about 95%) of the collected specimens belongs to the order of Coleoptera. All of these should be identified in order to find out which are the ones specially related to dead wood, also because no data on the ecology of all forest species exist.

 

 

The collected specimens are now being sorted and pinned. The pinned specimens are then organized in families and genera. In order to give a specific name to many of the beetles collected in the field these should be properly ordered so that their characteristic traits are visible, and in many cases an expert for a specific family or genus should be involved. (Photos: Serena Antonucci; Entomologist at work: Francesco Parisi).