In Costa Rica, the arrival of May Beetles, or Abejones de Mayo, on porches signals the onset of the rainy season. These beetles play an essential role in the ecosystem by pollinating, serving as prey for other species, recycling nutrients, and enriching the soil with their excrement. However, the population of these beneficial insects has been declining over the past 30 years, with light pollution being a significant factor.
Henry Alfaro Lara, residing in Aguas Bravas, reminisces about his childhood in the Sarapiqui area, where beetles were a nighttime fixture. “Estábamos ahí como viendo por la casa ahí donde se cachaban ahí en los postes de la casa entonces estamos conmocionados y ver esos meros bichotes bien bonitos,” Lara recalls, reflecting on how he and his friends marveled at the beetles’ size and presence.
Danilo Brenes Madrigal, a taxonomist at La Selva Research Station, highlights the nocturnal habits of beetles, which are often drawn to artificial lighting. He emphasizes, “Entonces, si hay una concientización por parte de las personas de querer conocer más y cómo ayudar a que no suceda.” The phenomenon is that these beetles, in their attraction to light, can become exhausted or fall prey to birds.
Research indicates that the beetles’ natural instincts lead them into repetitive loops around lights. Dr. Jennifer Birriel, a physics professor, suggests that using traditional sodium lights could mitigate this issue, as they emit less blue light than LED alternatives. “It’s a growing problem that we have to get under control, for even ourselves, we have to have food to eat, if we don’t have insects that are pollinating, then we’re not going to have our agricultural source,” she explains.
Simple changes at home, such as using shielded or motion-sensor lighting, can make a significant impact in supporting beetle populations. In Sarapiqui, Henry Alfaro Lara remains hopeful about the future of May Beetles, stating, “Creo que poco a poco vamos creciendo y se pueden lograr muchas cosas.” He believes that as awareness grows, the coexistence of humans and wildlife will improve.
