AZA Updates Amphibian Husbandry Guide

Amphibian Husbandry Resource Guide

The AZA has released an updated Amphibian Husbandry Resource Guide, a user-friendly source to aid in the development of successful amphibian conservation programs. With more thna 6,900 species of amphibians in the world, there is still much to be learned about their natural history and captive husbandry requirements. This lack of information and expertise can impede the urgent action needed for the 500+ threatened species in risk of disappearing within the immediate future. The zoological community and private sector have made great strides within the last two decades regarding amphibian husbandry and reproduction techniques, and will continue to develop new and innovative methods each year. However, as amphibian populations wane, it’s important to quickly and effectively pool resources, share expertise and learn from shared experiences to effectively remain ahead of the extinction tide. You can find a rich array of other resources on amphibians on the AZA website.

Cindy Hoffman, Defenders of Wildlife

New experiment may offer hope for frogs facing chytrid

Probiotics bath

The golden frogs were given a bath in one of four probiotic solutions. (Photo by Brian Gratwicke, Smithsonian Conservation Biology Institute)

We usually think of bacteria as bad for us, but that isn’t always the case. For us humans, the most common examples of helpful bacteria, or probiotics, live in yogurt. Now, scientists believe amphibian probiotics may be the key to fighting chytridiomycosis, the fungal disease devastating frogs around the world.

A few years ago, Reid Harris, a biology professor at James Madison University, discovered that local salamanders that could survive chytrid played host to bacteria in their skin. Now, Brian Gratwicke, a research biologist at the Smithsonian Conservation Biology Institute, is collaborating with a team from Virginia Tech, James Madison, Villanova and Vanderbilt Universities in an experiment to see if similar bacteria can protect the Panamanian golden frog, which he calls “the poster-child for amphibian conservation.”

The first step is to find a probiotic that will stick to the golden frogs. In early December, the team began giving golden frogs baths using four different types of bacteria. Researchers gathered the potential probiotics from frogs in Panama in 2009. The finalists were chosen based on their ability to prevent chytrid growth in lab tests, with a preference for bacteria that are common in close relatives of Panamanian golden frogs.

Every two weeks, each frog is swabbed to check whether its probiotic has made itself at home. The tests take some time, so a month and a half in, the team is still waiting for results to see which probiotics are sticking. But they do have some good news already.

“The bacteria haven’t been causing any problems with the frogs and they all look healthy,” said Gratwicke, who emphasizes how important it is to use only beneficial bacteria. In addition to tracking weight gain and other visible characteristics, Shawna Cikanek, a student at Kansas State College of Veterinary Medicine is using frog poop to study stress hormones to get a better picture of the animals’ overall health and whether the bacteria are causing any stress.

The probiotics that stick to the frogs for a full three months will move on to the next round of tests, when bacteria-shielded frogs will be infected with chytrid to check for any adverse effects.

“Hopefully, the bacteria are going to do their thing and protect these little guys,” said Matt Becker, a PhD candidate from Virginia Tech who is conducting the experiment. Whatever probiotics make the cut will be tested again on golden frogs bred in Panama before scientists develop a final plan.

So far, chytrid has defied attempts to stop it. Scientists may be able to selectively breed frogs resistant to chytrid, but there has been very little work done so far in that direction. But there are high hopes for probiotics’ potential to protect frogs. “It’s a long shot, but it’s our best shot,” said Gratwicke.

Becker hopes that one day, probiotics will allow Panamanian golden frogs to return to their homes. “These guys are really neat and it’s so sad not to see them in the wild,” he said. “We have a moral obligation since indicators are pointing to humans as major spreaders of the disease through the frog trade.”

Meghan Bartels, Smithsonian’s National Zoo

Start Spreading the Word

Paul Crump

Houston Zoo Amphibian Program Manager Paul Crump meets a family attending the Milam County Nature Fest. The aquarium on the table holds Houston toad ‘ambassadors.’ More than 600 people attended the one day Nature Fest in Rockdale, Texas. (Photo courtesy of the Houston Zoo)

Learning about endangered species is the first step in helping to protect them.

In 1968, a small amphibian landed a spot on the list of “Rare and Endangered Fish and Wildlife of the United States.” Five years later, the Houston toad was included in the passing of the Endangered Species Act and became one of the first amphibian species in the United States, and maybe even the world, to be recognized as declining.

Today the Houston toad is no longer found in its namesake city, and fewer than 300 individuals remain in the wild, largely due to habitat loss.  The Houston Zoo is working with the US Fish and Wildlife Service, Texas Parks and Wildlife Department, Texas State University and the Environmental Defense Fund to ensure the toad’s survival. The Zoo also works with private landowners to restore habitat and monitor populations in Houston toad counties. But before we can involve a landowner in the project we have to find them–and that’s where the Zoo’s education and outreach programs come in.

Mainstream media of course plays a major role in the effort.  A recent front-page story in the Houston Chronicle highlighted the need for private landowners to participate in the restoration project. The article generated a dozen responses from interested landowners and raised the profile of the effort. But grassroots efforts also play an important role.

Through our collaboration with the US Fish and Wildlife Service and the Texas Parks and Wildlife Department, the Zoo has developed opportunities for the presentation of education and outreach programs in counties northwest of Houston, the Houston toad’s current range. In late February, a landowner workshop sponsored by Texas AgriLife Extension and the Texas Forest Service brought 200 landowners together to learn about woodland and pond management and how to get involved in the Houston toad recovery project. Recently, three members of the Houston Zoo Conservation Department participated in the Milam County Nature Fest 2012. Supported by the Texas Parks and Wildlife Department, the festival drew more than 600 participants from surrounding communities in prime Houston toad range for a day of nature exhibits and demonstrations, crafts and games for children and an opportunity to meet Houston toads and hear from those who are directly involved in the toad’s recovery.

It’s one thing to tell the world about the importance of amphibians to the balance of nature. It’s another thing entirely when you see the smile on a child’s face when they have an up-close encounter with an endangered species. Then you know you’ve connected.

-Brian Hill, Houston Zoo

A United Front in Panama

The Panama Amphibian Rescue and Conservation Project implementation team met in Panama in February. From left: Pete Riger, Alan Pessier, Eric Baitchman, Paul Crump, William, Heidi Ross-Griffth, Angie Estrada, Jorge Guerrel, Della Garelle, Roberto Ibanez (Photo by Brian Gratwicke, Smithsonian Conservation Biology Institute)

Amphibian conservationists convened in El Valle, Panama, last month to plan the future of our fight to save amphibians. We didn’t do any collecting this trip, as frogs are much harder to find during the dry season. Parts of the country, including past collection sites in the Darien region, are also currently too dangerous. Instead, members of the project’s implementation team met with the El Valle Amphibian Conservation Center (EVACC). We are joining forces and looking at ways we can work together as one organization with two campuses.

Dr. Alan Pessier of San Diego Zoo Global facilitated the two-and-a-half day strategic planning session where a SWOT analysis was used to identify the organizations’ combined Strengths, Weaknesses, Opportunities, and Threats. Participants included Heidi Ross, director of EVACC; Roberto Ibañez project director in country; Brian Gratwicke, project coordinator; Angie Estrada and Jorge Guerrel, project staff; Peter Riger and Paul Crump, Houston Zoo; Eric Baitchman, Zoo New England; Della Garelle, Cheyenne Mountain Zoo.

The outcome was an ambitious and detailed action plan to achieve our mutual goals of creating assurance colonies of Panama’s most vulnerable amphibian species, and ultimately re-establishing their healthy wild populations. We plan to expand our ability to house more priority species and breed them reliably, better communicate progress on our work to interested parties, continue to improve husbandry and increase efficiency, identify staffing and equipment needs, prioritize research projects, and develop re-introduction criteria.

Dr. Della Garelle, Director of Conservation, Cheyenne Mountain Zoo

National Zoo Successfully Collects Sperm Samples to Save Endangered Frog

Gina Della Togna, an SCBI PhD student and native Panamanian, is one of the researchers in charge of the sperm collection procedure.

Gina Della Togna, an SCBI PhD student and native Panamanian, is one of the researchers in charge of the sperm collection procedure. (Photo courtesy of the Smithsonian Conservation Biology Institute)

With nearly one-third of all amphibian species at risk of extinction as the result of the deadly chytrid fungus, the Smithsonian’s National Zoo has taken a bold step toward preserving amphibian genes and the world’s incredible amphibian biodiversity. Researchers at the Smithsonian Conservation Biology Institute in Washington, DC, have begun to collect sperm samples from the Zoo’s collection of Panamanian golden frogs (Atelopus zeteki), which are extinct in the wild.

Although researchers have collected sperm samples from other amphibian species such as Mississippi gopher frogs and leopard frogs, there are no publications detailing sperm collection methods from Panamanian golden frogs. SCBI’s colleagues at the Maryland Zoo have aided in the process, providing advice to the SCBI researchers about the method to collect the frogs’ spermatozoa using hormonal stimulations.

“We currently have three other species of Atelopus in captive assurance colonies in Panama,” said Brian Gratwicke, an SCBI conservation biologist who leads the Zoo’s amphibian conservation program to curb global amphibian declines. “If we can freeze some of their sperm, golden frogs will be a model to secure the long-term genetic integrity of other toad species in similar situations.”

Gina Della Togna, an SCBI PhD student and native Panamanian, is one of the researchers in charge of the sperm collection procedure. Even though this is still a fairly new endeavor, Della Togna said she felt that it was easy compared to collecting sperm from mammals. After hormonal stimulation, spermatozoa are excreted in the urine from the frog’s cloaca, a multipurpose opening from which feces, urine and gases are expelled. This is in contrast to mammals, which possess specialized structures for the expulsion of waste and reproduction.

Atelopus zeteki sperm

A Panamanian golden frog sperm

Although sperm collection from this species has been successful, finding the most efficient and repeatable stimulation protocol is critical. Then, identifying the right cryoprotectant and freezing method will be another challenge. Researchers suspect that the cell component most likely responsible for the movement of the sperm, called a mitochondrial vesicle, has a unique structure compared to that of other animals.

“The mitochondrial vesicle is a very fragile structure,” Della Togna said. “Protecting this structure will definitely be one of our greatest challenges.”

Even in the face of numerous challenges, the research team overseeing the sperm collection and storage of the samples remains optimistic.

Pierre Comizzoli, an SCBI gamete biologist supervising the PhD project  is enthusiastic about the prospect of this endeavor and is charged with studying the complex golden frog sperm structure with Della Togna.

“It is always exciting to discover new biological mechanisms,” Comizzoli said. “Spermatozoa from each species have unique traits that needs to be well understood before developing preservation protocols.”

Other than its genetic and natural significance, the Panamanian golden frog is a meaningful symbol of culture for Panamanians. Pre-Columbian peoples used to make golden “huacas,” or sacred objects, in the image of these frogs, along with creating legends about these renowned frogs, which endure in the Panamanian countryside today, Della Togna said.

“This species does not exist anywhere else in the world,” Della Togna said. “You will find pictures and sculptures of it in local markets, in indigenous handcraft sales, and on lottery tickets, among places. Hopefully this project will help to ensure that one day you will be able to see them once again on the banks of Panamanian streams where they belong.”

Phil Jaseph, Smithsonian’s National Zoo

After devastating wildfire, Houston Zoo aims to help recover the Houston toad

This photo shows Bastrop State Park, what had been prime habitat for the endangered Houston toad. The photo was taken on January 13, 2012, slightly more than three months after the devastating wildfire that scored more than 34,000 acres and destroyed 40 percent of Houston toad habitat in the Park

This photo shows Bastrop State Park, what had been prime habitat for the endangered Houston toad. The photo was taken on January 13, 2012, slightly more than three months after the devastating wildfire that scored more than 34,000 acres and destroyed 40 percent of Houston toad habitat in the Park. (Photo courtesy of Houston Zoo)

Last September, a tropical storm in Louisiana, combined with a cold front to the north of Texas pushed an exceptionally dry and windy air mass into the central part of the state.  These weather conditions, combined with drought-stressed vegetation in a fire-suppressed ecosystem created the perfect conditions for one of the worst wildfires in Texas history.

What is now known as the Bastrop County Complex fire, burned through a total of 34,300 acres including an area near Austin, the state capitol known as Lost Pines and in Bastrop State Park.  The area, prime habitat for the endangered Houston toad, experienced what is called a “stand replacing” fire, meaning it totally destroyed the forests and sterilized the soil.  The fire dealt a harsh and potentially fatal blow to the Houston toad, whose largest and healthiest populations dwell in the park and adjacent ranch land.

Last November, an assessment team of local, state and federal agencies issued a fire recovery plan.  On Friday, January 13 representatives from the Texas Forest Service, Texas State University, Texas Parks and Wildlife Department, the Houston Zoo and others gathered at a workshop to discuss next steps, ranging from short and long-term revegetation strategies and erosion control, to post-fire land and wildlife management. Support for the recovery effort was plainly evident as more than 250 concerned area residents turned out for the workshop.

The Houston toad’s future in the Lost Pines area is grim. The fire destroyed 40 percent of the Houston toad’s habitat in Bastrop County. The loss of tree canopy and screening cover is, of course, concern to a variety of wildlife species, but most notably the Houston toad, which tends to occupy areas with 60 percent to 100 percent canopy cover.  Upland forests in the Lost Pines area serve as occupied and dispersal habitat for the Houston toad and cover/shade is a necessity to facilitate distribution without desiccation.

Rachel Rommel, the Houston Zoo’s Conservation Communications Manager introduces a group of Capital Area Boy Scouts to Houston toads before the Scouts launched in the first of many efforts to restore Bastrop State Park, laying mulch and leaf litter in scorched Houston toad habitat in the Park.

Rachel Rommel, the Houston Zoo’s Conservation Communications Manager introduces a group of Capital Area Boy Scouts to Houston toads before the Scouts launched in the first of many efforts to restore Bastrop State Park, laying mulch and leaf litter in scorched Houston toad habitat in the Park. (Photo courtesy of Houston Zoo)

But first steps are being taken toward recovery.  On Saturday, January 14 Rachel Rommel, the Houston Zoo’s conservation communications manager led a group of Capital Area Boy Scouts in the first of what will be many efforts to restore scorched areas of Bastrop State Park, laying mulch and leaf litter in an effort to add organics to the soil and restore habitat for insects and toads.

Concurrently, Houston Zoo conservation staff is encouraging landowners with toad-appropriate environments in neighboring Austin and Colorado counties to welcome Houston toads that were head started at the Houston Zoo to their properties.

The 2011 fires were a terrible blow for the Lost Pines habitat and the Houston toad, but as long as there are toads at the Houston Zoo and Texans who care, there is still a chance for this endangered species to thrive again in the wild.

Brian Hill, Houston Zoo

Conserving Frogs and Identifying an Invader in Panama

A group of researchers at the Smithsonian Tropical Research Institute confirmed this frog's identity as the "greenhouse frog," Eleutherodactylus planirostris. (Photo courtesy of STRI)

A team of dedicated amphibian caretakers, volunteers and Smithsonian scientists assembled their field gear, chytrid swab kits and swamp boots. Preparation was imperative for the week-long field expedition to the remote tropical rainforest in the Darien Province of eastern Panama. The team’s intention was to survey the site, still relatively untouched by fungal amphibian disease, and to collect individuals of species targeted for conservation at the captive rearing and breeding facility at the Smithsonian Tropical Research Institute (STRI). As had been the case in the last expeditions to these little-studied places, there was also a high probability of finding new species.

But storms made it impossible to land a plane at the site, so the trip was canceled. Disappointed, the team went back to work at the captive-breeding facility.

At the same time, another group of researchers at STRI identified another species of frog. Instead of being “new” to biology, this was an invader, native to the islands of the Caribbean, but new to Panama. In late 2008, herpetologists heard unusual calls in the gardens of suburban Panama City. A lack of local knowledge and individuals for comparison made definite identification difficult at first, so a genetic technique called DNA barcoding was employed to finally confirm the frogs’ identity as the “greenhouse frog,” Eleutherodactylus planirostris. Since then, many more individuals have been collected, confirming their presence.

DNA barcoding complements the more traditional techniques of identifying species based on body shape and size. Barcoding uses standardized snippets of mitochondrial genes that vary between species but not within individuals of the same species. DNA from the greenhouse frog was compared to sequences available in large worldwide databases like GenBank, kind of like matching the picture of a criminal to one of the faces in a line-up of suspects.

In 2010, a group of scientists working at STRI published a paper on amphibian diversity established using DNA barcoding. The paper and study came in the wake of massive frog species die-offs in central Panama caused by the fungal disease chytridiomycosis. “This is the first time that we’ve used genetic barcodes—DNA sequences unique to a given species—to characterize an entire amphibian community,” said Eldredge Bermingham, STRI director and co-author. “STRI has also done barcoding on this scale for tropical trees on in our forest dynamics-monitoring plot in Panama. The before-and-after approach we took with the frogs tells us exactly what was lost to this deadly disease in this area—33 percent of their evolutionary history.”

Applying a technique like barcoding in new places results in new knowledge and also raises many more questions than it answers.  What will the effect of the loss of so many frog species be on the insects that the frogs ate and on the snakes and birds that ate the frogs?  How did an invasive frog species arrive in Panama City from the Caribbean?  More updates soon….from Panama!

–Charlie Hruska, Columbia University and Panama Amphibian Rescue and Conservation Project volunteer

Q&A with Dr. Eric Baitchman: Through a vet’s eyes

Dr. Eric Baitchman

Dr. Eric Baitchman of Zoo New England treats a frog for the deadly chytrid fungus. (Photo courtesy of Zoo New England)

Dr. Eric Baitchman, Zoo New England director of Veterinary Services, is the lead veterinarian for the Panama Amphibian Rescue and Conservation Project. We spent some time talking to Dr. Baitchman about his interest in amphibians and what he has learned from his participation in this vital conservation project. Here’s what he told us:

When did you first develop an interest in amphibians? What sparked this interest?

I can’t really say when or what it was that sparked my interest in amphibians. I’ve always been drawn to their diversity of shape, colors and habits, as well as to the types of environments that amphibians usually occupy. Amphibian life histories are fascinating as well, spending the first part of their lives in the water as tadpoles, undergoing metamorphosis, and then growing in to terrestrial adults–no other vertebrate undergoes such dramatic changes in their life cycle.

What has been the most rewarding aspect about your participation in the Panama Amphibian Rescue and Conservation Project?

The work with the rescue project is truthfully a culmination of every reason I became a veterinarian in the first place. It is most rewarding to me to apply my skills as a veterinarian to make a meaningful impact on the conservation of entire species. The individual animals we care for in the rescue project represent what may amount to the last survivors for each of their species, entrusted in our care to assure their continued existence on this planet. I can’t imagine how anyone could find more reward from their work than that!

Has your work in Panama affected your veterinary approach at Zoo New England?

I have learned a great deal about amphibian medicine and their normal physiology through my work in Panama. Virtually everything I’ve learned there, I’ve been able to apply at home when caring for the amphibians in our own collection at Zoo New England, as well as advising other zoos on amphibian medicine through my role as an amphibian veterinary advisor for institutions accredited by the Association of Zoos and Aquariums.

If there is one thing that people should know about amphibians, what is it?

Unfortunately, people should know the danger amphibians are in all over the world. Amphibians everywhere are declining at alarming rates–so much so, that not since the extinction of the dinosaurs has there been this great a loss of species from a single taxon of animals.

What are simple things that people can do to help improve the lives of amphibians in the wild, including those in their own backyard?

There are many ways that you can make a difference and help improve the lives of amphibians. Here are some simple ways that everyone can help: recycle to keep waterways clean; use biodegradable and other “green” cleaning products to keep phosphates and other chemicals out of the water; keep chemicals out of water run-off by not fertilizing your grass or using pesticides; be mindful of your water use, especially in the summer when there is a higher risk of droughts (shallow water is more concentrated in pollutants than free-running water); and don’t put anything down a storm drain as it usually drains directly to a river or pond.

Brooke Wardrop, Zoo New England

Continuing drought and Texas wildfires pose new hurdles for an endangered toad species

Paul Crump

Houston Zoo Amphibian Conservation Manager Paul Crump prepares to release Houston toads in the area of Bastrop State Park. The park was devastated by recent wildfires. (Photo courtsey of the Houston Zoo)

Sixty years ago John Wottring, an amateur herpetologist, and Ottys Sanders described Bufo houstonensis, the Wottring Toad, what is now popularly known as the Houston toad.

In the 1960s the toad disappeared from the Houston area as its historic range was taken over by tract housing and commercial development and an extended drought.

In 1973 it was included in the passing of the Endangered Species Act, likely one of the first amphibian species in the United States, maybe even in the world, to be recognized as declining.

Fast forward to the summer of 2011 and we find that the Houston toad is again threatened by an extended drought and a devastating wildfire that consumed thousands of acres in the toad’s primary habitat, a state park near Austin, the state capitol.

The partners in the Houston toad recovery project, the Houston Zoo, Texas State University, the Environmental Defense Fund, U. S. Fish and Wildlife Service, and the Texas Parks and Wildlife Department, are working to assess the impact from a wildfire in early September that incinerated almost 55 square miles near Austin, destroying more than 1,500 homes and taking two lives.

The level of destruction was shocking and stunning. Major wildfires had been seen in the area in the early 1900s. But none approached the scale of the fires in September.

The fires incinerated a major remaining habitat for the Houston toad, the 6,000-acre Bastrop State Park. The Houston toad is found in isolated populations across nine counties between Austin and Houston. But Bastrop State Park was the toad’s primary habitat.

It will be weeks before the recovery team has an estimate of the impact of the wildfire on the habitat and the toads.

As the wildlife impact is assessed this fall, the Houston Zoo Houston Zoo toad team will develop “assisted reproduction” techniques to get Houston toads to breed reliably and in large numbers. These procedures will then be used to keep the captive assurance colony alive and genetically healthy, and when the time comes, to produce hundreds of thousands of toads for reintroduction.

While the future of the Houston toad in the wild may have dimmed due to the wildfire impact, there is hope. Always hope.  Segments of habitat remain and could be used to bolster the area’s toad population. As Texas State University biologist Dr. Michael Forstner told Houston Chronicle reporter Shannon Tompkins: “They’re pretty tough little guys. As a species, they’ve lived here a long time. This kind of thing has happened before and they’ve recovered. But it’ll be decades before we know all the impacts of this fire.”

(Editors note: To read Houston Chronicle reporter Shannon Tompkins’ September 18, 2011 story about the impact of the Bastrop wildfires visit

Brian Hill, Houston Zoo

The Fascinating Wyoming Toad

Wyoming toads

At around six weeks, the toadlets look like miniature (half-inch) versions of the adults. (Courtesy of Cheyenne Mountain Zoo)

A North American toad is fighting its own battle with chytrid, a battle just as devastating as the one frogs in Panama are facing. The Wyoming toad (Anaxyrus baxteri) is one of the most endangered anurans (frog or toad) in North America. Historically, they were found in the Laramie Basin of southern Wyoming. Up until the mid 1970s, they were common throughout this region, but since then, the population drastically declined. Major threats are loss of habitat, pesticide usage and chytrid fungus. In 1994, the last wild toads were rescued from extinction when they were collected and sent to a captive breeding facility. One day, their tadpoles could be released back into the wild, thanks to Cheyenne Mountain Zoo (CMZ), and other zoos and federal facilities now breeding Wyoming toads.

The CMZ Amphibian Propagation and Research Center is a bio-secure area and closed to zoo guests to help keep chytrid fungus and other diseases out of the breeding population. CMZ’s Wyoming toad population for 2011 consists of 17 males and 17 females. However, due to limited space for tadpoles, not all of the toads are bred each year. The Wyoming toad studbook keeper and population manager determine what the best matches are to maximize and maintain genetic diversity. CMZ also monitors the overall health of each toad and decides whether they are fit for reproduction.

During most of the year, CMZ’s goal is to keep the toads healthy and growing with exceptional water quality, properly supplemented feeder insects and regularly changed UV bulbs. As spring approaches, we confirm our recommended pairings and prepare for something somewhat disconcerting for an animal keeper–we have to chill our toads in the refrigerator! In order for them to breed successfully, the toads require a period of cool hibernation as would be experienced in the wild. This is a very delicate time for them because their immune systems are suppressed.

Amphibian Propagation Center

Cheyenne Mountain Zoo's Wyoming toad room in the Amphibian Propagation Center. (Courtesy of Cheyenne Mountain Zoo)

A few days prior to hibernating, the toads are not given food. As their metabolism slows, so does their digestive tract, and undigested food could make them sick. Their room is slightly cooled from 75 degrees to 65 degrees and the lights are turned off the day before entering the hibernaculum, which is basically a fancy refrigerator. Each tank of toads has its own tub filled with wet gravel, carbon, sand and moss. The toads are weighed, placed in the tubs and the temperature is set to 52 degrees. The next day, it’s turned down to 45 degrees, the following day to 41 degrees and finally, down t

o a chilly 38 degrees. The toads will remain at this temperature for 35 days, misted with chilled water to maintain humidity and checked on about twice a week. We have to limit the number of checks to reduce the amount of environmental disturbance.

After 35 days, the toads are slowly warmed up in reverse order of the cool down. It’s believed the hibernation helps produce the natural hormones that would trigger reproductive behavior in the wild. The toads are placed back in their normal husbandry tanks and offered a few insects. They should be ready for breeding the next day.

Many species of amphibians are not able to be bred in a captive environment. For the Wyoming toad, it was discovered they require supplemental hormones in addition to hibernation in order to reproduce. The females are given their first hormone injection in the morning and placed in a breeding tank. Six hours later, the males are given a hormone injection and the females their second. The breeding tank has about one-and-a-half inches of water and some plastic floating plants. A recording of Wyoming toad breeding calls is played for 24 hours while the pairs are together. (Hear a sample of the Wyoming toad call) By the next morning, the female should have hopefully produced eggs fertilized by the male.

On June 1, 2011, six pairs of Wyoming toads were placed together at CMZ, and all of them produced eggs! Unfortunately, two of the egg masses were infertile, but in total, CMZ had about 2,000 tadpoles. 1,792 of them were released back into the wild in Wyoming. Based on valuable genetics, CMZ held back 60 tadpoles for future breeding.

Wyoming toad

A Wyoming toad in the wild. (Courtesy of Cheyenne Mountain Zoo)

Each year, staff from CMZ, other zoos and U.S. Fish and Wildlife Service survey Mortenson National Wildlife Refuge for offspring from previous released Wyoming toads. This is a non-public access refuge, and reintroductions were stopped at this site in 2005 due to chytrid. The site allows us to see if the population could continue even though chytrid was present. Tadpoles are now released at a different location, which prevents us from confusing recently released animals with those naturally produced in the wild.

Length, relative size, weight, habitat conditions, temperature and wind speed are just some of the data recorded during the survey. Most importantly, though, is collecting a swabbed sample from each found toad to see if chytrid is present. The toads are also given a microchip under their skin for permanent identification, enabling us to know how many different toads are found. If a microchipped toad is caught again, a scanner will tell us.

Cheyenne Mountain Zoo is very proud to be an important participant in the Wyoming toad recovery program!

Jeff Baughman, Conservation Center keeper, Cheyenne Mountain Zoo