Mission: Vernal Pool Egg Masses

Salamander egg masses, VS user 4ggreenteam

Research Question

How is climate change affecting reproduction in amphibians that breed in vernal pools?

You're Invited

In this warming climate, vernal pools and the amphibians that breed in them are likely to experience significant changes. Warm winters could affect wood frog hibernation. Increased spring temperatures may lead to rapid snowmelt and change the timing of when vernal pools fill with water. Reoccurring droughts could cause the pools to dry out earlier in the summer. What will happen to the species that rely on vernal pools to reproduce? Help us track how these changes may affect wood frog and salamander eggs in vernal pools.

Mission Steps

Wood frog, VS user 34bred
  1. Locate a vernal pool near you (how do I do that?).
  2. Determine the best time in the spring to complete the mission. Use this map to help you.
  3. Gather your materials for fieldwork, including:
  4. Head out to your vernal pool. Look around for either wood frog, spotted, or blue-spotted salamander egg masses. Record evidence of what you do or do not find on your Vital Signs Freshwater Species and Habitat Survey.
  5. Estimate the total number of egg masses that you find in the pool. Record the number in the “How many are there?” section of your datasheet (page 2B). Note: Egg masses means groups of individual eggs.
  6. missionvpeggmasses_022218.jpg
    1 to 10 wood frog egg masses, Aram Calhoun
  7. Post your "found" or "not found" observations to Vital Signs. Remember that not found data matters!
  8. Become an expert on your pool! Keep an eye on your pool throughout the year. Leave a note in a comment on your observation with the date when you first notice all the ice melted in the spring and the date when the pool dries up in the summer or fall. This is important data for tracking how climate change is impacting the vernal pool.
Spotted salamander egg mass, VS user 4rpurple

Note: Use caution collecting data in this fragile habitat!

  • Leave dogs and other pets at home when you go to your vernal pool.
  • No more than two people in the pool at one time.
  • Limit your steps in the pool as they may disturb the egg masses.
  • Leave egg masses attached to vegetation or sticks. Larvae and adult specimens can be temporarily removed from the pool to be photographed.
  • At the end of your visit, carefully remove mud, leaves, and twigs from your boots and equipment. Spray them down or soak them in a 10% bleach solution (do this far from the pool). Wash your hands carefully. This will protect you and other amphibians from disease.

Why this Mission Matters

Wood frog egg mass, VS user 4hgreen

Vernal pools are unique habitats because they appear each spring and dry up in the late summer in most years. This makes them ideal locations for wood frogs, spotted, and blue-spotted salamanders to lay their eggs, as fish and other egg and predators are either absent or rare. A large majority of these amphibians are known to return to the same pool where they hatched year after year. If the pools dry out too early in the summer, tadpoles and may not have time to develop. If the conditions of the pool aren’t right in a given season, salamanders may not lay eggs at all. In this fast-changing climate that has been resulting in shorter winters and drier summers, we need to monitor the impact on wood frog and salamander reproduction so that we can determine how best to conserve their critical breeding habitats.

Teacher Resources

Find useful information for conducting this investigation with your class on the Mission: Vernal Pool Egg Masses Teacher Resources page.