Spring Amphibian Migration 2010


Widespread declines in amphibian populations have raised global concerns.

NJ Audubon, in partnership with
NJ Fish and Wildlife Endangered and Non-game Species Program
 and Conserve Wildlife Foundation of NJ, looks to learn about migratory movements of these populations so that we can more effectively protect their habitats.

To become a volunteer, visit the ENSP website.

Amphibians often play important and keystone roles in the natural world as indicators of functioning healthy ecosystems and as part of the predator - prey relationship. Like birds, they often signify a "canary in the coal mine" because widespread declines may indicate far reaching problems in the ecosystem. Herpetologists around the world have initiated research and conservation efforts to identify problems associated with these declines and come up with solutions to counteract them. The incredibly high extinction rate of some species can be attributed to:

  • Human disturbance
  • Habitat destruction
  • Encroachment
  • Pollution
  • Introduced predators

Maintaining stable populations of amphibian populations requires suitable habitat with abundant food supplies, breeding areas, hibernation sites, and safe travel between  these sites. The increase of development throughout the northeast continues to separate hibernation sites from breeding pools with treacherous road crossings that amphibians must endure. Several species of amphibians, called vernal pond obligates (VPO) only reproduce successfully in vernal ponds.  Vernal pools only hold water for several months in the spring - this ensures that fish can not live there and will not eat the amphibian's eggs or young.  VPOs literally put all their eggs in one "basket."

Spotted Salamander egg mass Wood Frog egg mass
Photos by Mike Bisignano

Generally these amphibians, which include frogs, toads and salamanders, live in upland forests protected by leaves and logs or underground. Come the first warm rainy night in early spring, they conduct widespread movements to reach these ponds where they search for mates, breed and lay their eggs for the next generation. 

Few people are aware that they may have these amphibians living in their backyards or in adjacent woodlots. Even a lesser number understand that they make amazing migrations between their hibernation and breeding sites. They often have to cross a road. As noted previously, crossing a road is not an easy task for a wood frog or a spotted salamander on a good night, but crossing on a rainy night when drivers' vision is challenged due to poor visibility due to road spray, glare caused by oncoming headlights and windshield wiper smear, is nearly impossible. Often citizens never recognize the amphibian loss on local roads, as nocturnal scavengers welcome the easy food source and the roads are "clean" by morning.

Looking for more information on vernal pools and specific amphibian species that use them? Click here.


So...what do we do?

1) Identify amphibian crossing sites.
Amphibians follow historic migratory routes.  The partners elicit volunteers to conduct nocturnal surveys or "drive arounds" to identify potential amphibian crossing sites for future study.

These volunteers drive local roads on appropriate weather nights to look for frogs and salamanders crossing roads; they may also be asked to collect amphibian mortality data for the NJ Endangered Species Program (ENSP) according to accepted scientific monitoring protocols.

2) Train volunteers to be Amphibian Crossing Guards.
Volunteers for this project become part of the ENSP Wildlife Conservation Corps. These volunteers help amphibians negotiate dangerous road crossings during the most stressful time of their life cycle.  In addition to benefiting the animals, these amphibian activists are asked to act as ambassadors for the project by educating others in the community about amphibian migrations and the conservation management challenges we face regarding amphibian populations and ecosystem health. 

3) Watch the weather.
VPO's make this dangerous migration on the first warm rainy nights in early spring.  Volunteers need to be willing to be out in the rain and be willing to be called upon as the weather unfolds. 

4) Help amphibians cross the road.
Amphibians tend to be cool and slimy....
but, the experience is truly "warm and fuzzy!"

Photos by Mike Anderson

Click below to view a short video
showing the volunteer training and
two nighttime crossings.

(Video includes two quick shots of "squished" critters,
to show the hazards they face when crossing roads.)

To become a volunteer, visit the ENSP website.

Click here to read the following articles about Amphibian Migration and Amphibian Crossing Guards:

Chaperones to an Amphibian Dance - April 2, 2009
Township right to give critters the right of way - February 20, 2008
Independence Twp. helps frogs get to the other side - February 17, 2008 
Saving New Jersey's salamanders, frogs, toads - March 14, 2007
Saving amphibians isn't easy - March 19, 2006



For additional information, call, write or email
NJAS Department of Education
 Center for Research and Education
 600 Route 47 North
 Cape May Court House, NJ  08210
  (609) 861-0700  

New Jersey Audubon Society (NJAS) is a statewide, not-for-profit, membership organization committed to preserving New Jersey's habitats and species biodiversity.  We invite your support through
membership and participation in our programs.