FALMOUTH, Maine — On the third Saturday of July, more than 1,400 volunteers across Maine jumped into their skiffs, boats, and kayaks for the 2021 Annual Loon Count. Now, four months later, the Maine Audubon released the data from the count, which shows an increase in the adult population but a decrease in chicks.
Officials said in a release Monday that about 50 volunteer counters who weren’t able to make it last year due to COVID-19-related reasons once again joined the count, so volunteers were able to look for loons on 328 lakes — 20 more than in 2020.
Maine Audubon said chick estimates were down from 414 last year to 224 this year.
According to Loon Count Manager Tracy Hart, it’s too early to tell if that marks a temporary dip or a new trend for loon chicks. She said similar dips have been noticed multiple times in the 38 years of the Maine Audubon loon count and the chick population has rebounded each time.
“We aren’t certain why chick numbers are down this season, but it is likely a combination of reduced nesting success from early extreme rainstorms which flooded some nests; washouts from boat wakes; aggression from non-nesting loons; chick or egg predation; some nests being abandoned due to human disturbance, and chicks being run over by boats," Hart said in Monday's release. "In addition, sometimes loons simply take a break from nesting — they don’t necessarily breed or breed successfully every year.”
Estimates for the adult population are up, from 2,974 last year to 3,446 this year, according to Maine Audubon. These estimates are for areas south of the 45th parallel — roughly south of a line from Rangeley to Calais — where enough lakes are counted in order to make a reliable estimate.
“We had been watching a two-year decline in the adult population that began in 2019 and showed a further reduction in 2020," Hart said. "We are happy to report that adult numbers are back up this year and estimated to be even higher than ever, continuing the general upward trend and recovery that we have seen throughout the history of the loon count.”
According to officials, the count provides a vital snapshot of the population at the same time and with the same methods each year. It is like a barometer that shows biologists how the population is doing compared to prior years and helps track those changes over time.
"The adults did rebound, there was a three-year decline, so we were starting to wonder if it was a trend so it's nice to see that rebound. The chicks have been mostly flat throughout the history of the loon count and there have been six dips like this one, so we are expecting that it'll probably rebound just like those other six times," said Hart.
Hart said although she hopes it's is a temporary dip in chick numbers, there was a heavy rainstorm in early June in some parts of the state which did flood out the nests of some loons.
"If they re-nested, the second clutch may not have hatched in time for the loon count, we know some nests were flooded by wakes, several weeks after one nest had eggs washed out by wake, a fisherman with a fishfinder saw an oval shape and when he investigated found a loon egg near the abandoned nest," said Hart.
Collisions between boats and chicks were reported and loon boat collisions seem to have surpassed lead poisoning as the leading cause of death in adult loons.
Hart added where there are people, there are more trash bins, and scavengers such as raccoons, that can increase and predate loon nests.