Butterflies in extinction from Elba brambles, it is necessary to let light pass

Butterflies in danger of extinction from brambles and reeds on the Island of Elba but small interventions on the vegetation (cuts to improve solar radiation) favor the deposition of Zerynthia cassandra eggs on the nourishing plants.

Legambiente highlights this by reporting a study published in Insect Conservation and Diversity and edited by biologists from the University of Florence which demonstrated that "freeing the plants of Aristolochia (the host plant of the caterpillars of the butterfly) covered by brambles in a small area can allow to lay all the eggs produced by a female of Zerynthia cassandra ".

The experiment was conducted in the Butterfly Sanctuary on the Island of Elba - in the area dedicated to the butterfly of San Piero (Zerynthia cassandra) in the municipality of Campo nell'Elba - in collaboration with Legambiente and the Tuscan Archipelago Park and of the 'Project for the research and protection of particular populations of Lepidoptera and their nourishing plants on the island of Elba' and 'Research and conservation on the Pollinators of the Tuscan Archipelago and dissemination on the Lepidoptera of the park'.

The study started from the observation that "the abandonment of agricultural land and the afforestation of habitats of the prairies represent the main threats to butterflies in European and Mediterranean areas. A crucial objective for the conservation of lepidoptera is to maintain and / or restore the habitat quality through targeted management. However, there are few experimental studies that allow to derive data-based strategies to protect open grassland butterflies in the Mediterranean region. "

For this reason, the team of researchers from the University of Florence has developed a habitat management strategy for the conservation of the Italian endemic butterfly Zerynthia cassandra by adopting a three-step procedure to promote oviposition in the microhabitat in restored places to optimize the 'intervention.

Management consisted of cutting vegetation to increase irradiation and two years of monitoring showed that this procedure increased egg laying and larvae presence.

The model butterfly is the Italian endemic species Zerynthia cassandra which has recently been separated from Zerynthia polyxena on the basis of morphological and genetic data.

It is a monophagous species, that is, it feeds on few plants of the genus Aristolochia.

The researchers highlight that the population of Elba has a considerable conservation interest.