Post-season Summary Reports:
Read the latest 2025 report by Project Biologist Kevin Tolan, highlighting key insights from five years of the Vernal Pool Monitoring Program.
Past Reports:
Mercury and Vernal Pools
Mercury is a well-known threat to wildlife in lakes, ponds, and forests, but its presence and effects in vernal pools are poorly understood. VCE has conducted research to help fill this gap. VCE Conservation Biologist Steve Faccio collaborated with scientists from Dartmouth College to study how landscape features influence mercury (Hg) levels in vernal pools, and its accumulation in amphibians and invertebrates.
Mercury enters pools through rainfall, leaf litter, and snowmelt, and the high organic matter and low pH of vernal pools can convert it into the more toxic form, methylmercury (MeHg). Although few studies have examined mercury in vernal pools, mercury levels in forest soils are known to vary widely with forest type, canopy cover, and land use over small spatial scales.
Project Outcomes:
- Selected 20 pools identified through the Vermont Vernal Pool Mapping Project
- Evaluated Hg and MeHg levels and bioavailability
- Selected a subset of pools for more intensive biological sampling over time to assess sources and pathways of Hg and MeHg
- Determined how MeHg accumulates in breeding amphibians and invertebrates
- Assessed how amphibians may “export” Hg to the terrestrial food web
Click here to read the first publication from this project that was published in June 2019.
Tracking Salamanders
Among the most intriguing members of these ecosystems are salamanders that spend most of their lives underground, only to emerge with spring rains to migrate to the pools for courtship and breeding. This annual movement of salamanders spawned a parallel movement of scientists, citizens and policy makers united in the protection of vernal pools and their unique assemblages of life. Yet research by Vermont Center for Ecostudies biologist Steve Faccio in the early 2000s revealed that salamanders require habitat far beyond the water’s edge of a vernal pool: a surrounding forested “life zone” that had been largely unrecognized and poorly protected.
Faccio employed radio telemetry to track the movements of two species: the widespread and relatively common spotted salamander (Ambystoma maculatum) and the Jefferson’s salamander (Ambystoma jeffersonianum), a species of regional conservation concern in the Northeastern U.S. He focused on two breeding pools at the Marsh-Billings-Rockefeller National Historical Park in Woodstock, Vermont. After their spring breeding season, he captured 16 adult salamanders (eight of each species) and fit each with a tiny radio transmitter. He returned his 16 research subjects to their point of capture and began to monitor their whereabouts.
For both species combined, salamanders moved an average of 112 meters from their release points. Most emigrated from pools during overnight rains, but the timing, direction and distance traveled varied widely among individuals (from as close as 11 meters to as far as 405 meters). Females moved nearly twice as far (155 meters) as males (78 meters). This latter result may have important conservation implications if buffer zones around vernal pools are not large enough to include females. Habitat loss that disproportionately affects females could increase the risks of local extinctions.
By combining his results with data from other studies, Faccio determined that salamanders use an area extending 175 meters from a vernal pool’s edge, a salamander “life zone.”
Read more in one of VCE’s earliest publications, Research Notes.
