Firefly Occurrences in Croatia – One Step Closer from Citizen Science to Open Data*

Abstract

Fireflies (Coleoptera: Lampyridae), with more than 2 000 species in 100 genera worldwide, are a charismatic nocturnal species. Although popular in different cultures because of their association with warm summer evenings in childhood, fireflies are an under-researched insect. Like numerous other insects worldwide, fireflies have experienced declines in their distribution and abundance. Anthropogenic impacts and climate change are likely to influence their development, reproduction, and survival. A project called "Krešo Krijesnica" (eng. "Krešo the Firefly"), used a Citizen Science model of data collection, to determine where are the fireflies located and how abundant are they throughout Croatia. Citizen Science involves the participation of the general or non-scientific public in data collection so determining the basic demographic profile of the citizen scientists involved was also one of the project goals. During the first phase of the project (2019-2021), data on fireflies were provided by citizen scientists through a formal survey on social media (Facebook, Instagram). Phase two aims to open the fireflies' datasets to the public through various open data portals. In the three years of the project, more than 16 000 records of fireflies were collected and analysed from over 1800 sightings. Descriptive statistics showed that the highest firefly population density was found in central Croatia, which is consistent with the greater number of people living in this area and thus a greater chance of firefly detection. Higher number pf female reporters were noted during the project. The dataset collected in this Citizen Science project presents a valuable source of information to the scientific community, especially in the field of entomology, conservation biology and ecology.