Well, folks, it’s that time of year. Lakes are freezing over, and the season of loon rescues, raft building, and watchful monitoring has drawn to a close. Here’s a recap of what our team of biologists and more than 350 dedicated volunteers found this year. In total, we identified 157 territorial pairs and 123 nesting pairs in 2024, both records for Vermont! The number of nesting pairs resumed its upward trend following a three-year plateau from 2021 through 2023. Out of the 123 nesting pairs, 11 built nests at new locations and 85 successfully hatched a total of 125 chicks. However, this year also saw a drop in the rate of chick survival, with 81 out of 125 chicks (65%) surviving through August, compared to a 76% average from 2004 to 2023.
For the second year in a row, Vermont experienced flooding in July due to heavy rainfall. Three to seven inches doused the state on the anniversary of 2023’s historic flood, causing 12 nests to fail. Last year, nine nests failed due to flooding, six of them inundated during the July rain event. These numbers approach the recent high count of 13 flooded nests in 2019, but they contrast sharply with our count of just one flooded nest during the dry summers of 2020 to 2022.
The impact of summer flooding on loon nesting success is easier to measure than other possible contributors to reduced chick survival. As the Vermont loon population grows and expands to new areas, nesting pairs begin to occupy smaller lakes with more marginal habitat. This can mean that ideal nest sites are limited; for example, a new lake may lack vegetated islands or high-quality marsh sites that could provide cover during incubation. Some first-time nest sites could be more vulnerable than established sites to predators, such as eagles, big fish, or snapping turtles. In addition, adult loons must leave small lakes more often than large lakes to feed where fish are plentiful, which results in more time off-nest and less attention paid to chicks.
Even with this year’s lower chick survival rate, Vermont loon pairs are producing an average of about five chicks per decade, which is more than needed for a stable population. In other words, Vermont’s loon population is still growing, and a decline in chick survival is to be expected as competition increases for ideal territories and nest sites.
This year, VCE continued to partner with Vermont Fish and Wildlife on the Loons and Lead Tackle program. One of this year’s three loon rescues was of an adult female loon suffering from lead poisoning; read her story on our blog.
We thank the agency officials, loon volunteers, and others who help keep this program up and running. Without your generosity and passion for these animals, we wouldn’t be able to sustain this statewide program nor all of the conservation success that comes with it.
For more detailed results, including a table of key indicators dating back to 2008, read Loon Biologist Eric Hanson’s 2024 Vermont Loon Conservation Project Summary.