Effect of direct illumination on firefly (Photinus sp1) occurrence in Sorocaba, Brazil. Mean occurrence of Photinus sp1 (confidence interval of 95%) at T0, T1 and T2 (difference of means = 87.4 percent, 65.2 percent, and 46.9 percent,  respectively) with the light on (n = 363 transects) and off (n = 346 transects). A Wilcoxon test for mean occurrence on each transect among lights on and off had for T0, T1, and T2: P = 0.00015, P = 0.04042 and P = 0.01882 respectively. Graphic: Hagen, et al., 2015 / Advances in Entomology

By John R. Platt
7 July 2016 (TakePart) – Blink and you’ll miss them this summer. Around the world, people are reporting that local firefly populations are shrinking or even disappearing. The insect’s dilemma first came to the world’s attention at the 2010 International Firefly Symposium, where researchers from 13 nations presented evidence of firefly population declines and declared “an urgent need for conservation of their habitats.” Since then, additional conferences and several scientific papers have documented regional firefly disappearances, and at least two citizen-science projects are attempting to document the phenomenon, but the full scope of the problem remains to be uncovered, says firefly researcher Ben Pfeiffer, founder of Firefly.org, a website about the decline of the insects, also called lightning bugs. “It’s worrying,” said Pfeiffer. “When people see a habitat that’s got three, four, five different species of firefly flashing, each with a different flash pattern, it’s an amazing thing. It changes their lives, but few people get to see that anymore.” The exact extent of the decline is unknown, but early indications suggest that lightning bug populations have shrunk in many places and disappeared from others. “Everyone is reporting declines,” said Eric Lee-Mäder, codirector of the pollinator program for the Xerces Society for Invertebrate Conservation. The causes, however, appear to be clearer: a combination of habitat degradation and loss, light pollution, destruction of water tables, and pesticides, Pfeiffer said [and medical harvesting: Modeling effects of harvest on firefly population persistence]. “You can wipe fireflies out really easily,” he added. “It’s not hard. You’ve got a one-acre plot, and you put a house there. Good-bye, fireflies. They’ll never be there again.” [more]

Firefly Populations Are Blinking Out

ABSTRACT: Artificial night lighting is gaining attention as a new type of pollution; however, studies of its impacts are scarce. Fireflies provide good models to investigate its effects on nocturnal wildlife, since they depend on their bioluminescence for reproduction. This study investigated the impact of artificial illumination on firefly activity at the new campus of the Federal University of São Carlos (Sorocaba, Brazil). The flashing activity of different firefly species, especially Photinus sp1 (82% of all occurrences), was investigated during 3 years, before and after the installation of multi metal vapor spotlights. Quantitative and qualitative analysis, performed in transects at different distances from the artificial light sources, showed significant negative effects on Photinus sp1 occurrence. This study proposes fireflies as potential flagship species and bioindicators for artificial night lighting and for the first time quantifies its effects, providing subsidies for future conservationist legislations regarding photopollution.

Artificial Night Lighting Reduces Firefly (Coleoptera: Lampyridae) Occurrence in Sorocaba, Brazil