On Tuesday of this week, an opportunity presented itself I could not pass up: helping reintroduce Boreal Toad tadpoles on the Colorado River District (CRD) side of the Park. Boreal Toads live in a variety of wet habitats at high altitudes, 8,000 ft – 11,500 ft, and are native to Rocky Mountain National Park. The Boreal Toad is the only toad found in the Park.
Photo credit: National Park Service https://www.nps.gov/romo/learn/nature/amphibians_reptiles.htm
Over the last thirty years, the population numbers of the toad in Colorado have steadily declined. The toad is at risk and has been on the Colorado Endangered Species list since 1993. To learn more about the toad and its habitation in Colorado, an interagency Boreal Toad Recovery Team and Translocation Working Program formed involving Rocky Mountain National Park, Colorado Parks and Wildlife (CPW), and the USGS Biological Resources Division. Together, this team follows specific guidelines related to Boreal Toads, including how to reintroduce tadpoles in the Park.
For my part, I carried a pack filled with 179 tadpoles and 40 gallons of water two miles up a trail and then half a mile off the trail to the reintroduction pond. CPW folks came up from an Alamosa hatchery and delivered the toads to us at the trailhead. Each person carrying toads had a data person carrying the data sheets; seven of us carried toads and the rest helped with data.
When we got to the pond, we made sure the pH and temperature of the pond and the pH and temperature of the bags in the packs were the same. If not, we added water from the pond to the bags until they were within five degrees of each other. After my data person and I evened out the pH and temperature, I scooped up 3 – 5 tadpoles at a time in a measuring cup. Before releasing them into the pond, my data partner and I recorded how many tadpoles I had and which Gosner Stage they were in. We had tadpoles in the following stages: 26 (tadpoles with no limb nubs), 30 (tadpoles with limb numbs), 37 (tadpoles with back legs), and 42 (tadpoles with four legs and tiny tail). I had zero mortalities and 179 tadpoles in total.