Firefly Recap 2020

The 2020 Firefly Watch is complete, and it's time to crunch the numbers. While many science opportunities were cancelled this year because of the coronavirus, standing in my parents' back yard at night was not affected at all. 

I started with this project in 2018 and chose to continue at the same location in order to monitor the same population. Protocol for Firefly Watch is to count the number of flashes in three periods of ten seconds each on the same night. We record the number of flashes, the color of the flashes, the flash pattern (single flash, J shaped, double flash, etc.), and weather data- temperature, wind, cloud cover, and precipitation. I chose to use the same dates every year. I ended observation when after being shut out twice in a row. This year observations ended on September 3, the earliest end date so far.

Observations got off to a slow start this year. By the time I got through the first observation of June, I only had three flashes recorded. By the end of June, things were picking up. Flashes peaked slightly earlier than previous years, and lasted slightly longer. The post-peak crash wasn't as steep this year. Despite the slow start, early finish, and missing two observations because of vacation, the 2020 total number of flashes was the highest of the three seasons I've done Firefly Watch. 2018 had 694 flashes, 674 in 2019, and 708 in 2020. The increases and decreases year to year are slight, and statistically speaking the population is stable. 

I blame the slow start on the weather. My first observation was May 21, which was less than three weeks after our last snow flurry of the season. A warm winter gave way to a cold spring, which probably delayed firefly emergence.

I will credit the coronavirus along with the weather for the higher number of flashes this year. Fireflies prefer a dark night so they can see each other better. Due to the virus, baseball games were cancelled at the park adjacent to my parents' house. No stadium lights, and the lights at the school next door were off late in the season due to school being digital to start the year. There was no rain during any of my observations this year, and that made for better flying weather. No lightning also makes a darker sky.

I am already looking forward to the start of the 2021 season. Observations will be on Fridays and Mondays next year. Three day weekend getaways might have to wait until September, but as long as firefly numbers remain steady or increase, it will be worth the wait.