Making Headway for Imperiled Species One Egg at a Time
On a drizzly fall morning in Georgia’s Coastal Plain, seven biologists went hunting, but this wasn’t a typical hunt. They donned kneepads, headlamps, and gloves and set off crawling side by side across an open area of grasses and other low-growing plants surrounded by spindly pines.
They were searching for two-inch clumps of translucent eggs laid in the mud of a seasonal wetland. Their target was laid by strikingly beautiful female frosted flatwoods salamanders, which deposit their eggs amongst the vegetation of wide, shallow depressions on the landscape in hopes they’ll soon fill with water.
During breeding season in Georgia and Florida, ARC Field Biologists comb temporary wetlands, alongside our partners, looking for the eggs of these federally listed Threatened salamanders so we can collect them.
Although removing their eggs may sound unconventional, it’s part of a strategic way we’re bolstering their tiny, declining populations.
We employ a conservation technique called headstarting for these salamanders, one of the most critically imperiled in the Southeastern US, and also for several other at-risk amphibians and reptiles, including the gopher frog, Threatened bog turtle, Threatened Chiracahua leopard frog, and Endangered Houston toad.
Headstarting is exactly what it sounds like. Young animals are raised in captivity past their most vulnerable life stages and then released back into the wild, literally giving them a head start. When these species are very small (or when they’re eggs), they’re especially easy targets for predators, and they’re more likely to be lost to other natural causes as well, such as drought.
For frosted flatwoods salamanders, headstarting begins with collecting their eggs from seasonal wetlands. The eggs are then transported to nearby mesocosms (large outdoor tanks), where they eventually hatch into larvae with gills (like tadpoles). In this protected space, they feed and grow until they’re large enough to have their best chance of surviving, and then we release them back into their wetlands in the spring.
Why Headstarting?
Since the 1980s, headstarting has been used to boost populations of amphibians and reptiles. In the early days, it was most commonly done with sea turtles.
Although it’s been used with birds and even with mammals (Ross et al. 2021), it’s particularly well suited to amphibians and reptiles, the majority of which lay eggs and are often relatively easy to raise. By contrast, species in which the young imprint on the adults, like most birds, are more challenging to headstart because those raising them must make sure the young animals do not see humans as their parents.
For reptiles and amphibians, conservation professionals have successfully raised and released large numbers of individuals and effectively increased the populations of several species, including Blanding’s turtles, eastern hellbenders, diamondback terrapins, and plains gartersnakes (McElroy et al. 2023, Kaunert et al. 2024, Roosenburg & Kennedy 2019, King & Stanford 2006).
It’s Not Enough: Closing the Loop
Despite its promise, headstarting is not a fix-all solution.
When we attempt to address a complex challenge, such as species declines, without getting at the root causes, it’s like trying to stop a leak with a sponge. Ultimately, the underlying issues will seep through and continue to cause problems.
Case in point, Mullin et al. (2020) reported that headstarting alone cannot address landscape-scale habitat modifications or persistent threats like invasive species and pollution, highlighting the complexity of conservation efforts. For long-term success, headstarting must be integrated into broader conservation strategies.
And that’s exactly what we’re doing in PARCAs, or Priority Amphibian and Reptile Conservation Areas, across the US. Here, in the most important remaining places for imperiled amphibians and reptiles, we’re implementing the targeted solutions that are most likely to ensure they can thrive by developing a custom conservation plan, which looks different in each PARCA.
To do so, we carry out three main steps. We begin with population discovery, inventory, and monitoring. Second, we use the most up-to-date science available to dig into why that species is rare or struggling and identify the threats causing its decline. From there, we can move on to the third and most tangible step: building a conservation plan and getting to work.
More often than not, that work includes habitat restoration. Habitat loss is one of the biggest drivers of species’ declines (Luedtke et al. 2023).
Restoring healthy habitats for amphibians and reptiles helps ensure the places they inhabit have suitable conditions for survival and reproduction. This is especially important for species that are being headstarted; the sites where they’re being released must be able to support them.
Headstarting enables us to bolster existing populations, start new ones, and buy time while we’re implementing broad-scale habitat protection and restoration. Together, these targeted, strategic actions help increase the size, connectivity, and frequency of amphibian and reptile populations across the landscape.
That’s the power of the PARCA approach, and while this is a large-scale strategy, we also celebrate the very small things. Every egg, tadpole, larva, and juvenile animal raised and released back into the wild represents our commitment to giving imperiled species their best chance to swim, hop, slither, and crawl across these stunning landscapes for generations to come.
References
Kaunert, M. D., Brown, R. K., Spear, S., Johantgen, P. B., & Popescu, V. D. (2024). Restoring eastern hellbender (Cryptobranchus a. alleganiensis) populations through translocation of headstarted individuals. Population Ecology, 66(2), 93–107. https://doi.org/10.1002/1438-390X.12171
King, R. B. & Stanford, K. M. (2006). Headstarting as a management tool: a case study of the plains gartersnake. Herpetologica 62 (3): 282–292. https://doi.org/10.1655/0018-0831(2006)62[282:HAAMTA]2.0.CO;2
Luedtke, J.A., Chanson, J., Neam, K. et al. (2023). Ongoing declines for the world’s amphibians in the face of emerging threats. Nature 2023: 1-16. https://www.nature.com/articles/s41586-023-06578-4
McElroy, C. L, Windmiller, B., Berkholtz, J. Wilder, E. R., Welch, J. F. Shoemaker, K. T., & Kamm, M. D. (2024). Recovery of a Blanding’s Turtle Population through Nest Protection and Headstarting. Northeastern Naturalist, 31(sp12), E25-E42. https://doi.org/10.1656/045.031.s1203
Mullin, D. I., White, R. C., Lentini, A. M., Brooks, R. J., Bériault, K. R., & Litzgus, J. D. (2020). Predation and disease limit population recovery following 15 years of headstarting an endangered freshwater turtle. Biological Conservation, 245, 108496. https://doi.org/10.1016/j.biocon.2020.108496
Roosenburg W. M. & Kennedy, V. S. (Eds.). (2019). Ecology and Conservation of the Diamond-backed Terrapin. Johns Hopkins University Press; Illustrated edition.
Ross, A. K., Lawes, J. C., Elphinstone, A., Stutsel, S., & Letnic, M. (2021). Headstarting as a cost-effective conservation strategy for an endangered mammal. Current Biology, 31(10), R465-R466. https://doi.org/10.1016/j.cub.2021.04.017