If you follow us or any other wildlife organizations on social media, you may have noticed that our posts these last few days have been inundated with amphibians. It may seem like odd timing, given that our early breeders (wood frogs, spotted, and Jefferson salamanders) completed their crossroad migration last month. But the reason is simple – it’s Amphibian Week!
Close up of an American toad that hitched a ride during this year’s crossing. Photo Credit: Nikki Griffiths
Globally, amphibians are disappearing faster than any other vertebrate group. The International Union for the Conservation of Nature (IUCN) estimates that 41% of amphibian species categorized for their Red List are currently facing extinction. That estimate is likely conservative, given that these creatures are often small and difficult to survey, rendering many species data deficient. This is concerning from multiple perspectives. From an ethical standpoint, we don’t want any wildlife to go extinct except maybe, in my extremely biased opinion, certain types of ticks… (I began my career as a moose technician and saw firsthand the terrible consequences that winter ticks have on these behemoths). Beyond that though, amphibians are tasked with a lot of responsibilities and carry out their work efficiently and without complaint. The list is inexhaustive but here are a few things that amphibians are doing for us and our planet as we speak: filtering water, sequestering carbon, eating pests (like mosquitos!), serving as prey for countless predators, helping researchers study regeneration (with hopeful applications to the future of organ transplants), aerating the soil in your garden, indicating where water sources have been contaminated by pollutants, and giving everyone who meets them a reason to smile.
Wildlife biologist Christine Healy teaches the scouts about CWF’s work to protect the federally threatened bog turtle. Credit: Jim Kasprzak.
The classic justification for conserving wildlife is, of course, to protect diversity for future generations. While that’s not my go-to motivation for pursuing this line of work (I believe in the intrinsic value of nature and feel we are obligated to serve as good planetary stewards), I always feel over the moon when kids demonstrate the passion and interest in getting involved in this critical mission early on. When I received a request from Scouts BSA Troop #276 for assistance in earning their environmental science merit badge, I was eager to comply.
Earning a merit badge is no easy feat. It takes time and hard work, which is why attaining the rank of eagle scout, requiring the acquisition of at least 21 merit badges in addition to demonstrating leadership and service to the community, is such an achievement. For the environmental science badge, scouts must 1) study the history of the environmental movement in the US; 2) understand vocabulary relevant to wildlife, pollution, and green energy; 3) complete an activity relevant to seven of the following categories: ecology, air pollution, water pollution, land pollution, endangered species, pollution prevention, pollination, and invasive species; 4) complete a comparative study between two distinct habitat types; 5) practice drafting an environmental impact statement; and 6) research three career opportunities available in the field. Like I said, no easy feat, but Sebastian, Aidan, and Josh are up to the task.
Waterloo Village in Byram Township, Sussex County is more than a tourist attraction and local gem, it is also home to the largest cross-road amphibian migration in New Jersey. Each spring, frogs, toads, and salamanders stir from their hibernation to make their way to their breeding sites. Some of these sites, like the one at Waterloo, are vernal pools – small, temporary bodies of water that appear in early spring as snow melts and rain and groundwater gathers, and disappear throughout the summer as they evaporate. The ephemeral nature of these pools can’t support fish, which would prey on amphibian eggs and larvae. Vernal pools therefore provide some protection for amphibian offspring, with many species such as wood frogs and spotted and Jefferson salamanders – both of which are listed as New Jersey species of Special Concern – relying exclusively on these vernal pools for breeding.
The greatest challenge for amphibians breeding at Waterloo Historic Village is crossing Waterloo Road. Living in the most densely population state takes a toll on many species of wildlife in the form of habitat loss, degradation, and fragmentation. Each year, many amphibians become victim to vehicular collision as they move from their hibernation sites across Waterloo Road to the vernal pool in which they reproduce. Amphibians may be disproportionately affected by vehicle-caused road mortalities compared to other wildlife because of their tendency to migrate en masse to breeding sites. These annual road mortalities can have devastating effects on amphibian population sizes, especially for the local at-risk salamander populations. In fact, as little as about 10% annual risk of road mortality in spotted salamanders can lead to the local extinction of an entire population.
Wood Frog eggs. Photo courtesy of MacKenzie Hall.
To address this problem, the Conserve Wildlife Foundation of New Jersey (CWF) and the New Jersey Endangered and Nongame Species Program (ENSP) organized amphibian rescue efforts. Since 2002, dedicated volunteers have assisted frogs, toads, and salamanders across Waterloo Road during the busiest migration nights. This aid has proven effective in reducing amphibian road mortalities, but it is not a permanent solution to the problem. Efforts are underway to construct under-road tunnels to help guide amphibians safely across Waterloo Road. These tunnels will provide safe passage for these critters throughout the breeding season, including on their migration back into the woods where they will hibernate. Since this return migration is more sporadic and less weather-dependent than migration to the vernal pool, it is much harder to protect amphibians as they make their way back to the forest.
This year, CWF scientists have begun the initial phases of research to understand current amphibian population sizes and the impact of vehicle traffic on these animals at Waterloo. Scientists and volunteers have been out 7 days a week since amphibian migrations began in late February to tally daily roadkill on Waterloo Road. This study will be used to evaluate changes to frog, toad, and salamander populations as the under-road amphibian tunnels are installed. CWF scientists have also conducted egg mass counts in the vernal pool at Waterloo Village to estimate the current population sizes of the different amphibian species in the area. Having this knowledge will allow CWF to improve on future projects to minimize road-related human-wildlife conflicts.
Spotted Salamander egg mass. Photo courtesy of MacKenzie Hall.
Along with improving conditions for amphibians in this location, CWF’s work at Waterloo Village will serve as an example of New Jersey statewide initiatives to reconnect wildlife habitat as a part of the Connecting Habitat Across New Jersey (CHANJ) program. The goal of CHANJ is to make our state landscapes more permeable to wildlife movement so that all of New Jersey’s residents – human and wildlife – will have the space they need to thrive.
In an effort to bring people and wildlife together in a positive way at Waterloo Village, CWF scientists are leading educational walks for the public and local schools. Through hands-on interaction, local residents can learn about and appreciate the remarkable wildlife right in their own back yards and what they can do to support conservation efforts.
All New Jerseyans can help wildlife this season by planting native plants for their gardens, building bat boxes where bats can roost, and, of course, by keeping an eye out on the roads, especially on warm, rainy nights when amphibians might be migrating.
