Amphibian Conservation

Collaboration in Conservation: A Striped Newt’s Story

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By Mark Vassallo, curator of amphibians

It’s just before dawn in the Apalachicola National Forest of Northern Florida, and light is glinting off the dew of the long-leaf pine trees as the humidity peaks. These conditions are just right for one of nature’s most adaptable animals to undertake an incredible journey. A striped newt (Notophalmus perstriatus) stirs under the water of a temporary pond.

Today, this young newt is preparing to travel from the relative safety of this ephemeral pond, to which he has been introduced with the help of the Coastal Plains Institute (CPI) and the Detroit Zoological Society (DZS). CPI has been dedicated to preserving the long-leaf pine ecosystem since 1984 and continues to work to maintain this unique habitat through scientific research, land management, and environmental education within Florida. The striped newt, recently listed as “threatened” in Florida, needs all the help it can get.

This very pond where the newt plans to emerge has been constructed and maintained through the work of CPI. The DZS and CPI have been collaborating on releases such as this one since 2017, and this particular newt has been bred and raised at the Detroit Zoo by staff who specialize in amphibian care with this moment in mind, the opportunity to re-introduce species and preserve biodiversity.

Newts are raised at The Detroit Zoo.

The striped newt can adapt to life outside the water, an ability that amphibians have been perfecting for millions of years. When conditions are right, the striped newt’s skin will begin to thicken and granularize, helping to hold moisture more efficiently than its typically slippery and smooth skin. The newt’s tail will become narrow, round, and less like a paddle, making traveling over dry ground much more efficient. This life stage is known as an “eft.”

As the newt slips out from under the water and moves onto land, its bright skin coloration advertises its toxicity to any potential predators who wouldn’t mind getting an early morning snack. Moving deliberately through the ground cover, the newt encounters a drift fence and travels along the edge of it. After a few feet, it drops into a 5-gallon bucket, which CPI staff soon recovers and processes. This fence and the corresponding bucket are all part of a scientific study undertaken by CPI to measure the success of introductions such as this one. Monitoring these drift fence arrays is no easy task, and CPI volunteers are tasked with checking these traps every day for up to seven months of the year.

Many months ago, the amphibian care staff at the DZS’s National Amphibian Conservation Center (NACC) began preparing to breed our resident population of striped newts. All the conditions for reproduction had to be just right. The correct water quality, depth, and egg-laying materials were painstakingly researched and implemented. With the addition of a specialized water filtration system, known as a reverse osmosis system, the amphibian department staff had complete control over the “makeup” of the newt’s water. It could reach the correct parameters to mimic the natural environment where these newts live in the ephemeral wetlands of Florida and Georgia. The plumbing required for this filtration unit was installed and tested by the DZS’s maintenance staff. The work required careful drilling through the walls of the NACC to run plastic plumbing lines to deliver the filtered water to the bio-secure and husbandry spaces where animals are kept. This was no small feat and proved to be a great example of how the DZS’s conservation success is a team effort spanning all the departments of the Zoo.

After all this effort to prepare, the real success occurs when the striped newt begins the reproduction process. The male will hold the female in an embrace known as amplexus; during this embrace, the male rubs the female’s snout with his chin and releases pheromones, which are fanned towards the female with his paddled tail. Once the female is receptive, the male will drop what is known as a spermatophore. From this point, the female will accept the spermatophore, and internal fertilization will occur.

Once the eggs are laid, usually on long emergent vegetation that has been placed in the habitats of the striped newts, the baby newts will begin to develop. This process can take several weeks and can be affected by temperature. The larvae are tiny, sometimes measuring about 8 millimeters, and very thin, resembling a small piece of wood or a twig, making them difficult to see with the naked eye. These tiny larvae are fed small invertebrates and aquatic worms, which have also been cultivated by the talented staff at the NACC. Once the newts have reached about 13 millimeters, they are eligible for release, counted and carefully shipped to Florida when conditions are just right in the wetlands for release. 

After a long journey from an egg in the bio-secure breeding room at the NACC to the Florida wetlands, our newt is now being counted and sent into the forest by the staff and volunteers at CPI. This newt will likely spend years in this “eft” life stage, moving through the long-leaf pines and feeding on invertebrates. If conditions are right in the coming years, the newt will be beckoned back to the temporary ponds by rainfall and favorable environmental conditions, where it could potentially breed naturally and help bolster the numbers of this unique and increasingly rare amphibian. In 2023, the DZS and CPI introduced 227 striped newts back into the wilds of Florida, increasing the numbers of this important animal and furthering the case for collaboration in conservation.

Volunteers from Coastal Plains Institute release newts into the wild.

The striped newt repatriation project ended the season with a beautiful surprise. Several months ago, CPI staff dip-netted two large, gilled paedomorphs out of the new, rubber liner-enhanced release pond, where CPI staff released 227 young larval striped newts. The newts had been raised here at Detroit Zoo, sent to Florida on July 11, then released on July 12 after an acclimation process. In the coming weeks, four of the 227 were encountered in drift fence buckets and inferred to be exiting the pond and going terrestrial as efts. No others were seen after that. We worried that most animals were lost to predation by turtles and predaceous invertebrates. However, to end the season and ascertain whether some newts had survived and opted to live an aquatic life, CPI captured the two paedomorphs.

These paedomorphic animals may represent a persistent aquatic ‘population’ there. We hope and expect they will go on to reproduce. That will be determined next year by dipnet and drift fence sampling. This is the best news of the 2023 striped newt repatriation project field season and one of the highest points in the 11-year ongoing recovery efforts.

DZS raise newts and prepare them for wild release.

A Song in the Darkness: Audio Loggers and Panama’s Imperiled Amphibians

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Authored by Mark Vassallo, Detroit Zoological Society (DZS) Amphibian Department Supervisor.

The cloud forest of central Panama is a unique and mysterious place, full of rare creatures and plants that call these moisture-laden peaks home. At night, the jungle writhes with life as the nocturnal world takes over the mountainsides. In this veil of darkness and nestled in the elevations of these dense jungles, some of the earth’s rarest amphibian species reside. Many of these species are yet to be described by science, and others are considered to be extinct.  As I gazed up at the gathering rain clouds on the volcanic peaks of El Valle, I could not help but wonder which of these potentially extinct amphibians could still be out there.

I have been traveling to El Valle, Panama for the last seven years to work with the El Valle Amphibian Conservation Center (EVACC). This organization is run by Edgardo Griffith and Heidi Ross, a husband-and-wife biologist team, who have dedicated their lives to the conservation of Panama’s most endangered amphibians. Usually during these trips, I am undertaking projects involving the installation of life support and infrastructure or helping troubleshoot specific husbandry issues that arise in one of the modified shipping containers in which EVACC houses seven species of Panama’s rare and endangered amphibians, including the iconic Panamanian golden frog (Atelopus Zeteki). 

A Warzewitsch’s frog was identified in the area.

While those types of jobs are on the docket for this trip, we also have an important task to complete that will bring us into the upper reaches of the cloud forest in the hopes to hear a sound that could mean some hope for the imperiled amphibians of Panama. The sounds we are hoping to hear are the calls of thought-to-be-extinct amphibians, including Raab’s tree frogs (Ecnomiohyla rabborum), large and highly unique arboreal frogs who lays their eggs in tree cavities and can glide through the air to evade predators. In the last year, EVACC has begun the process of deploying audio loggers in some of the area’s hard-to-reach elevations to listen for the calls of amphibians like the Rabb’s tree frog that are widely thought to be potentially extinct. 

The audio loggers are sturdy boxes that contain a microphone, batteries and SD cards accompanied by a digital screen. The idea is that these listening devices, which are programmed to turn on during the dusk and nighttime hours, will pick up the call of one of these rare frogs. If a call from one of these frogs is detected on the logger recording, this would give the biologists at EVACC a very good lead on the areas where intensive surveys could take place to potentially locate this species.

Armed with some GPS coordinates, batteries, fresh SD cards and rough information about the audio logger’s location from a member of the last group who placed it, we headed up the mountain to start our journey. As we began to climb, the heat and humidity was intense — our clothes were soaked in less than an hour.  Large biting ants were swarming our boots as the incline steepened, and we came to a crossroads in the trail. We had reached the GPS coordinates but realized that these coordinates could not be correct. At this point, we decided to attempt to leave the trail and start climbing up what seemed like a cut in the dense jungle, which may have been caused by mudslides and heavy rains, certainly nothing even resembling an actual trail. The going was difficult as the clouds began to gather. Buckets of heavy rain soon began dumping on us, causing the mud to loosen and give, making the more vertical sections especially precarious. In addition to watching your footing in the jungles of Panama, it is also important to watch where you put your hands. Eyelash vipers and stinging insects of all kinds tend to rest on branches and sticks at about eye level. All of these thoughts were keeping our senses sharp as we broke through clearing after clearing, each time hoping that this was the top of the mountain and the audio logger would appear like a shining beacon amongst the dense jungle. Yet, each time the clearings revealed even more vertical walls of vines and thick jungle vegetation to climb. Our resolve was fading, but we pressed on. At one point, my balance gave way, and I fell face first into the side of the muddy slope. As I raised my head, I noticed I was face to face with a tiny gem of a frog. It was a blue-bellied poison frog (Adinobates minutus). This toxic little frog was just staring back at me, probably wondering why a silly, hairless ape had bothered to climb this far up a mountain during a thunderstorm. 

A rainforest rocket frog was identified in the area.

The rain was finally letting up, and this gave us a little boost as we could see some sunshine emanating from what looked like a break in the jungle ahead. As we approached, sharp painful sensations started overwhelming my hands and wrists. We were wading through a large column of sharp bladed grass, which when brushed against, caused a paper cut like lacerations on the skin. Once we emerged from the brush and into the clearing, we realized we had reached the top. The jungle was so dense there was no real spot to even look out to enjoy the view. We immediately got to work searching for the audio logger.  I looked left then right and passed through some thick brush. Then I saw it — a strip of white that stood out in the landscape of green. It was one of the zip ties used to attach the logger to the tree. We had found it! After several minutes of exulted celebrations and numerous high fives, we swapped out the SD cards and batteries, the unit was reprogrammed, and we locked up the protective case. The trip down was more like a ride down a luge course made of mud. This did make the process faster but certainly not any safer. 

Once we finally arrived back at the EVACC grounds, we were exhausted and coated in mud and insect bites but satisfied and content that we had achieved a seemingly insurmountable challenge. After a shower and a cold beverage, I walked out into the moonlight on the grounds of EVACC. Once again, the clouds were beginning to gather around the El Valle mountains, and my eyes settled on the tips of those green jungle peaks, wondering if the logger we had reset for another four months would record a sound of hope.

Learn more about the EVACC foundation and make a donation online to help them ensure the survival of Panamanian amphibian species for generations to come.

Mark Vassallo is pictured with an audio logger.

Foreshadowing the Amphibian Crisis: The Wyoming Toad

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Authored by Blake Klocke, curator of amphibians for The Detroit Zoological Society

The Detroit Zoological Society (DZS) is helping a species hop back from extinction!

The Wyoming toad was once found in abundance in the Laramie River Basin. However, catastrophic population declines were observed throughout the 1970s. By 1983, the Wyoming toad was thought to be extinct. Biologists could make no clear determination for the cause of the decline.

With a bit of luck, a small population of about 20 animals was rediscovered in 1987 at Mortenson Lake, bringing hope that the species could be saved. Rescuing the species by bringing it into captivity was the only option to avoid extinction.

Amphibian Chytrid Fungus and Preventing Amphibian Extinctions

Throughout the 1980s and 1990s, amphibian declines were common around the globe – something that puzzled biologists. At the time, there was no obvious answer as to why multiple amphibian species were rapidly disappearing in Australia, Central America and the United States. In 1998, the amphibian chytrid fungus – a microscopic primitive fungi – was discovered to be the cause of disease resulting in these declines. Biologists have attributed the amphibian chytrid fungus to be the primary cause of approximately 100 amphibian extinctions and to have impacted more than 700 amphibian species. No other wildlife disease has impacted biodiversity as much as this fungus. 

The Wyoming toad is highly susceptible to the amphibian chytrid fungus. The National Amphibian Conservation Center at the Detroit Zoo was built in part as a response to the amphibian biodiversity crisis, which assisted in keeping some of the most imperiled species away from the edge of extinction. The Wyoming toads at Detroit Zoo live in a biosecure room, which keeps them safe from being potentially exposed to the disease!

Ex-situ rescue, which is when a species is brought out of the wild into captivity for conservation, is a last resort. Unfortunately, we are often left with no other options. Rescuing a species in captivity requires intensive management to maintain the population, and it’s a long-term commitment by a dedicated and passionate team.

Wyoming Toads at the DZS

The DZS was an early partner in rescuing Wyoming toads, welcoming our first toads in 1995. A Species Survival Program (SSP) was also formed in 1996 to organize efforts among zoo partners and the U.S. Fish and Wildlife Service. The amphibian team at the DZS has produced 10,730 Wyoming toad tadpoles, toadlets and adults for reintroduction since joining the program in 2001! These animals are bred at the DZS and later sent to Wyoming to be released into the wild. The Center for Zoo and Aquarium Animal Welfare and Ethics at the Detroit Zoo has also led studies that have helped improve the husbandry of Wyoming toads in captivity by comparing the preferences for substrate, which improves our care for this very important species.

Caring for Wyoming Toads at the Detroit Zoo

Mike Andrus is the primary colleague who takes care of the Wyoming toads at the DZS, and his years of experience in the amphibian department caring for these toads is one of the keys to Detroit Zoo’s success. Mike handles more than 30 toads at the Zoo

Mike Andrus is the primary colleague who takes care of the Wyoming toads at the DZS, and his years of experience in the amphibian department caring for these toads is one of the keys to Detroit Zoo’s success. Mike handles more than 30 toads at the Zoo, where he carefully cycles the temperature throughout the year, including when he places the toads in a refrigerator to hibernate. This process requires a lot of fine-tuning and experience – and prepares the toads, which are each equipped with their own individual ID to track genetics, for breeding.

Mike Andrus holds a Wyoming toad in the biosecure room.

Wyoming toad tadpole reintroductions

In June 2022, Mike traveled to Laramie, Wyoming to participate in the reintroduction of Wyoming toad tadpoles. Several thousand tadpoles were sent from SSP partners for reintroductions. It was a busy day, as tadpoles were placed in bags of about 100 animals and methodically distributed around reintroduction sites.

Tadpole reintroductions are very important to continue supporting the recruitment of new toads into the population. In the months following the tadpole reintroductions, hundreds of recently meta morphed toads are found — each one with the potential to make it to adulthood and breed in the wild.

Bags of tadpoles produced by zoos around the country and U.S. Fish and Wildlife Service acclimate before reintroduction.

Wyoming toad surveys

In August 2022, I participated in the Wyoming toad field surveys and an annual SSP meeting. The team was successful in finding many young toads, likely from tadpole reintroductions and some wild breeding. The most exciting part was finding more than 15 breeding-sized adults! Some of the toads had a small identification tag, demonstrating that reintroduced juveniles and adults from captivity are surviving in the wild.

Wyoming toads were found at all four field sites the team visited, a very good sign for a species that was once thought to be on the verge of extinction. Currently, there is no method to mitigate the amphibian chytrid fungus in the wild, but in recent years there are an increasing number of rediscoveries of species once thought to be extinct and vulnerable species persisting in the presence of chytrid.

We’re optimistic that the Wyoming toad will soon hop back from extinction!

A toad reintroduced months beforehand was found during our surveys and appeared in good health. Adult toads receive a tiny tag, much like a micro-chip for a cat or dog, that let us know who they are when they are found in the wild! 

Thank you to our SSP partners, who make saving this species possible:

• U.S. Fish and Wildlife Service

• Kansas City Zoo

• Cheyenne Mountain Zoo

• Omaha’s Henry Doorly Zoo and Aquarium 

• Como Zoo

• Mississippi River Museum

Notes from the Field: Monitoring Mudpuppies’ Lives Under the Ice

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The Detroit River in the winter can be an inhospitable place. The temperatures dip into the teens, and the wind whips large plumes of snow from the tips of frozen waves. This large and fairly fast-moving river flows south and southwest, connecting Lake St. Clair and Lake Erie. The river plays an important role as a shipping channel for freighters carrying industrial compounds and other materials used for manufacturing. 

Underneath all of this ice and hustle and bustle, one of the river’s most curious and secretive animals is carrying about its business, breathing with large, bushy external gills, foraging along the rocky bottom for food and undergoing mysterious mating behaviors. This animal is known as the northern mudpuppy (necturus maculosus maculosus), and the frozen and harsh conditions of the Detroit River are just what it’s been waiting for all summer long. 

Winter view of the Detroit River taken from Belle Isle Park.

Mudpuppies are amphibians who inhabit lakes, streams and rivers all throughout the U.S. Midwest and into parts of Canada. It is a type of fully-aquatic salamander that utilizes external gills, which are flush with blood and used to extract oxygen from its aquatic environment. Its tail is large and paddle like, and its skin is covered in a thick layer of slime. These salamanders, like all amphibians, have permeable skin and are considered to be a good indicator of environmental quality. This is one of the reasons the Detroit Zoological Society (DZS) began tracking the health and abundance of mudpuppies back in 2009.

In 2016, the Michigan Department of Natural Resources elevated the conservation status of the northern mudpuppy to a species of special concern. Since that time, the project has continued and expanded, focusing primarily on Belle Isle Park in the city of Detroit. The Detroit Zoo utilizes minnow traps to capture the mudpuppies without harming them while still collecting important data. The traps are baited with smelt and catfish bait to lure these aquatic salamanders into the minnow traps. The traps are set on the first day of the survey and pulled in on day two, so that the animals spend the least amount of time possible inside.  If a mudpuppy is found inside, DZS staff proceeds to gather data and observations about the animal, including size, weight and gender. The gills are checked for health and examined for parasites. The digits on all the limbs are checked for malformations, which could indicate the potential presence of pollutants in the river. 

Mudpuppy being weighed and examined before being released back into the Detroit river.

Once these measurements are taken, the animal is tagged with a Passive Integrated Transponder tag, which is injected into the base of the tail. This transponder can be scanned if the animal is captured again. Additionally, it tells DZS researchers useful information that can be used for future data analysis. In addition to these measurements, data is collected on water quality and additional environmental conditions, such as temperature and dissolved oxygen content. 

Based off the data so far, most mudpuppies are caught in late fall or early winter. During this time, male mudpuppies are pursuing females in the quickly cooling shallow water close to the island. Many times, staff has observed male and female mudpuppies in the same trap this time of year, most likely with the female entering the trap first before the eager male mudpuppy follows her inside. Once mudpuppies have successfully bred, the females deposit their eggs in spring, and within a month or two, the eggs hatch into several hundred baby mudpuppies!

All of this drama is taking place out on the frozen Detroit River. With ice floats and enormous boats hovering overhead, these specialized amphibians continue to live and breed intertwined in an urban environmental landscape that still holds many secrets yet to be revealed.

– Mark Vassallo is an amphibian department supervisor for the Detroit Zoological Society.

Amphibian Breeding Season

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Spring is the time of year when most amphibians in the wild are emerging from hibernation, breeding, and eventually laying eggs. This pattern also holds true for the animals at the Detroit Zoo’s National Amphibian Conservation Center (NACC). Every year in the early months of spring, the top-notch staff at the NACC facilitate hibernation, breeding and rearing for endangered amphibians from all over the world with the intention of releasing them into their respective habitats in the wild. A few of these species include Wyoming toads (Bufo baxteri), striped newts (Notophalmus perstriatus) and Puerto Rican crested toads (Peltophryne lemur). Amphibians are highly sensitive creatures who rely on the environmental conditions of their native habitats to cue their natural cycles of breeding and to maintain their overall health.  The NACC staff are experts at recreating these environmental cues.

Facilitating breeding in Wyoming toads, for example, is a complex process involving temperature changes and natural material for burrowing. The amphibian staff use a refrigerator to replicate the natural winter cool down experienced by these critically endangered creatures, and to ease them into a state of lowered activity and metabolism. The amphibians are also provided with a special mix of substrate to burrow into during this period – very similar to how Wyoming toads in the wild burrow below the frost line during the cold months.  When they warm up after this simulated winter, the toads at the NACC are ready to breed and are paired up with mates according to the recommendations of the Association of Zoos & Aquariums’ (AZA) Species Survival Plan (SSP) for Wyoming toads. An SSP is a cooperative breeding program that is overseen by AZA-accredited institutions that breed and house animal species who are endangered or threatened.

Another example of the specialized care required to breed the unique animals at the NACC is found in the reproduction patterns of striped newts. Endemic to the long leaf pine forests of Georgia and Florida, these amphibians are known to congregate and breed in temporary pools during specific times of the year when the water levels are highest.  In order to mimic these events for the striped newts at the NACC, their habitats’ water levels are lowered for a period of time – before being raised dramatically. The natural breeding cues of the striped newts are also replicated in other ways, such as changing their “photo period,” or daylight/nighttime hours, in order to simulate different seasons.  Inside the animals’ habitats, the zookeepers also place specific aquatic vegetation that the newts have been known to prefer as sites for laying eggs.

            Puerto Rican crested toads are among the many amphibians who are known to begin breeding activities during periods of heavy and sustained rainfall. Existing only in several small isolated populations within Puerto Rico, these toads emerge from hiding during seasonal rains to find a mate and reproduce.  Making use of this knowledge, the intuitive keepers at the NACC have produced a “love song mixtape” which includes the calls of male crested toads as well as the sound of heavy rainfall. While this track may not win any Grammy Awards, it serves to stimulate the crested toads into amplexus, which is an embrace used by male toads to hold onto the female and fertilize her eggs.

After countless hours of logging temperatures, researching literature and testing water quality, the real reward comes for the staff at the NACC when these fragile and endangered animals are released into the wild having received a head start towards a brighter future. This year, in the month of June, the amphibian department at the Detroit Zoo released 3,393 Puerto Rican Crested Toads, 634 Wyoming Toads and 41 Striped Newts into native habitats ranging from the dry forests of the Caribbean Islands to the plains of Wyoming. The amphibian staff take great pride in having contributed to the conservation of some of the most important animals on the planet as well as in furthering the mission of Detroit Zoological Society.

– Mark Vassallo is an amphibian department supervisor for the Detroit Zoological Society

Frog-Themed Activities in Honor of World Frog Day!

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Spring is finally here — and so is World Frog Day! The weather is gradually warming up and plants are bursting through the soil, preparing to dazzle us with their blooms. Spring also brings the beautiful sounds of frogs and toads calling to each other. In honor of World Frog Day, we are sharing frog-themed activities that can be done at home with minimal supplies.

PT Borneo eared frog

Frogs live on six of the Earth’s seven continents, all of them except Antarctica. They are all different colors and sizes. The largest species of frog, the goliath frog, measures 8” to 12” in length. That is about the size of a piece of copy paper!  The smallest known frog, one of the microhylid frogs, measures less than half an inch, about the width of a regular size paperclip. If you have children at home, pull out a paper clip and a piece of copy paper. Have them compare the items to objects around the house to see what is larger than the world’s largest frog and what is smaller than the world’s smallest frog. Comparing sizes of different things helps people build number sense, or an intuitive understanding of numbers, an important skill for all of us to master, especially young children.

Green Mantella - Adam Dewey

Michigan is home to 13 species of frogs and toads. It is usually easier to hear them calling or singing to each other, than it is to actually see them. That is because they are well camouflaged, meaning they blend in with their surroundings. It is important to know which species of frogs and toads live in certain areas. They are considered bioindicators, which means they are species of animals who are greatly impacted by the health of the environment. If the water, wetlands and other places they live are polluted or contaminated, they cannot survive. If their habitat is clean and healthy, many species or individuals will be living there, all calling out to each other in a beautiful chorus.

FrogWatch - Bullfrog

The Detroit Zoological Society (DZS) leads a FrogWatch Chapter (aza.org/frogwatch and detroitzoo.org/animals/frogwatch/) to train people, like you, to recognize and record frog calls around Michigan. The data that people submit helps DZS staff and researchers to analyze and better understand frog populations throughout our area and across the country.

IMG_0474

This spring, consider spending time outside in the evening to listen for frogs and toads. You can practice being a frog and toad researcher, or a citizen scientist, by learning the calls and recording information like date, temperature, weather conditions, the time you start and stop listening, and the species you hear. The Michigan Department of Natural Resources has short recordings of each species on their website to help you learn them. Practicing recording data is an important skill, especially for kids. Send your data to Rebecca Johnson (rjohnson@dzs.org) or Mike Reed (mreed@dzs.org). Next year, you can join us for training to become a certified FrogWatch participant. The earliest calling frogs will be starting soon, the wood frogs and spring peepers, so pick a night where the temperature is above 40 degrees Fahrenheit and head outside to listen!

 

Notes from the Field: Protecting Amphibian Biodiversity in Peru

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You heard recently from one of our education experts about how the Detroit Zoological Society is working with Peruvian schools to conserve the rainforest through outreach and education. Conservation of the biodiversity in the Peruvian rainforest has been a priority of the Detroit Zoological Society for over a decade, and we have many programs in the rainforest that help to achieve this goal. One of our programs focuses specifically on amphibians, and that is where I have the great fortune to visit this incredible location.

Boana calcarata

There are over 600 species of frogs in Peru, with more species discovered every day. With this high number of species, Peru is called a “biodiversity hotspot.” These “hotspots” are very important to monitor for changes, because while there are many species they are all very dependent on one another. Small changes can cause drastic effects. Amphibians are some of the most sensitive animals, because their skin absorbs everything in the environment. If amphibians begins to get sick or have difficulty surviving, that is an excellent clue that something is wrong in the environment. All over the world, amphibians are currently having difficulty with changes we are seeing in the environment- because we are seeing global changes, it is extra important to study the animals in areas like the Amazon, where amphibians are in higher concentration, to try and understand patterns in these changes.

Boana calcarata call image

The convict tree frog (Boana calcarata) is a frog found in the Napo River region. This sound recording and image were made by the National Amphibian Conservation Center during a survey.

In order to keep an eye on the amphibians in the Peruvian Amazon, staff from the Detroit Zoo’s National Amphibian Conservation Center conducts surveys for frogs twice a year. This means we physically go out and look for frogs. Because we know we cannot possibly see all the frogs, also record the songs of frogs at night. Hearing the songs can help us guess numbers of animals singing and help us to hear the songs of species that are difficult to find on visual surveying. In addition to surveys, we monitor weather data in the Napo River valley. We have our own weather station that collects year-round information about the valley region. We also use small data loggers to collect immediate, specific “microclimate” changes where we visualize species breeding (for example: on a specific plant or under leaf litter). The weather data helps us understand both immediate changes in behavior of frogs, as well as changes in populations over time.

Weather stationDr. Ruth Marcec-Greaves downloads six months’ data from the weather station.

While data collection and surveying are important, fostering appreciation of animals in the local community is the primary goal of the visits to Peru. Our hope is that educating the community and creating excitement in future generations will help to preserve these animals for the future. The “Club de Protectores de Anfibios,” or Amphibian Protectors Club, is a club comprised of high school students that are local to the Napo River valley region. The club was founded in order to help impart enthusiasm for amphibians and the environment.

In Peru, there are many misconceptions surrounding frogs. There is a general belief that frogs are bad luck and should be kept away from homes. When the Detroit Zoo staff visited the Amphibian Protectors Club in June of 2019, the club members taught us how the Amphibian Protectors Club is changing the community. The club members performed a play in which they explained another local belief is that a woman will become pregnant if she spends time around frogs. Told from the perspective of high school students, this was a chilling superstition. Through the play, the students explained that by participating in the club they have learned not only that this is a myth, but also frogs are important for human health and humans need to protect frogs. The club members have taught their friends and families frogs are important and have begun to see more frogs in their villages since this change in attitude.

Night HikeAn Amphibian Protector’s Club member observes a frog up close on a night hike.

The students from the club went on an overnight excursion with the National Amphibian Conservation Center staff, where we visited one of our regular field research sites. We took a late night hike in order to see frogs calling and breeding at this special location. At this site, we saw species of frogs the students do not commonly see in their villages. After a good night rest, the club rose early in the morning to hike to the nearby canopy walkway- a breathtaking experience where the club members were able to look down on the rainforest from the treetops. While these students live in the rainforest, many of them have not seen their tropical home from this perspective. They were inspired by this view, observing the unique habitat of rare and diverse species. One club member called it “the view of the animals,” and asked very advanced questions about some of the plants and insects he observed.

Canopy

This was an incredibly rewarding trip. The students showed us that their appreciation for the amphibians is making a difference. While I will not see them in person for a few months, the students will continue to speak with me over a WhatsApp chat (they named our group “Whatsappos,” because “sapo” means toad in Spanish). While I am away, the club meets monthly to survey in their home towns and the students will send me photos and descriptions of frogs the see. Over the app, we talk about the species and have a question and answer session. Their excitement is inspiring and infectious, and I am confident their enthusiasm will be what helps save species.

– Dr. Ruth Marcec-Greaves is the director of the Detroit Zoo’s National Amphibian Conservation Center.

 

 

Notes from the Field: Saving Tree Frogs in Honduras – Part III

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In my previous two blog entries, we examined three critically endangered species of tree frogs in Honduras and shared plans for the Detroit Zoological Society and the Honduras Amphibian Rescue and Conservation Center to begin a head-start program for tadpoles of these species to help increase their populations. If you haven’t had a chance to read these entries, click here and here.

Now, let’s take a peek at what the rescue center facilities look like, and the long-term vision for in-country involvement.

The facilities are currently located in El Jardin Botanico y Centro de Invastigacion Lancetilla, a botanical garden and research center run by Universidad Nacional de Ciencias Forestales. Construction began in 2015 through a collaboration of multiple institutions, including Omaha’s Henry Doorly Zoo and Aquarium, National Autononous University of Honduras, UNACIFOR, Operation Wallacea, Expendiciones y Servicios Ampbientales de Cusuco and the Honduran forestry department. By the spring of 2018, construction was completed and our team inspected the facilities. The team included myself, staff from Omaha’s Henry Doorly Zoo and Aquarium and the rescue center’s co-founder Brandon Greaves. The inspection was to assure that the facilities are ready to provide the best care, biosecurity and welfare for animals that will arrive later in the year.

The ingenious rescue center facilities utilize shipping containers in order to provide housing for the animals. The containers (called “pods”) are ideal for amphibian conservation and care as they are secure, well insulated and easily mobilized should the facility need to be relocated. The pods have full plumbing and electricity, with climate control to suit the needs of our three target species that live in the cool mountain habitats. Each pod is outfitted with a vestibule for caretakers to prepare for a bio-secure entry (which requires clean up and changing clothes).

The pods are outfitted with habitats for up to 1,200 animals (400 from each of the three target species: exquisite spike thumb frog, Cusuco spike thumb frog, and mossy red-eyed tree frog). Water for the animals is treated with reverse osmosis in order to make it safe for amphibians. All water and other waste leaving the pods is cleaned to prevent any contamination to animals of the Lancetilla Botanical Gardens. Live food items (flies, crickets, and other insects) are bred in-house in order to provide ideal nutrition and prevent non-native insect concerns. The individual habitats inside the pods are species specific, catering to the needs of each of the three animals with current, temperature, and substrate. In short…. I would like to live in the pods!

The rescue center facilities are in excellent condition and are ready for animals. As we prepare to bring animals in for head-starting, the rescue team is searching for the perfect local Honduran in order to care for amphibians full time. This individual will train at the Detroit Zoo’s National Amphibian Conservation Center in the care of amphibians. Once head-starting has begun, we will build outreach programs involving local Honduran schools and local researchers. Ultimately, the goal is for the rescue center to be entirely Honduran-run. Our Honduran partners are enthusiastic and we are excited to see their involvement grow.

Honduras is a country that does not receive much assistance in conservation, and the Detroit Zoological Society is proud to be a part of this groundbreaking project saving amphibians in this beautiful nation. We will definitely share more updates as we begin head-starting animals soon!

– Dr. Ruth Marcec is the director of amphibians for the Detroit Zoological Society and oversees the National Amphibian Conservation Center at the Detroit Zoo.

Notes from the Field: Saving Tree Frogs in Honduras – Part II

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As part of the Detroit Zoological Society’s (DZS’s) continuing efforts to save amphibians from extinction, we recently introduced readers of the DZS Blog to three species of endangered frogs that live in the Cusuco National Park in Honduras. These species are at high risk of extinction and we aim to help their populations. If you haven’t had a chance to read my previous blog entry, click here.

Amphibians are facing an extinction crisis, and one of the most tangible causes is disease. In my previous entry, I mentioned the chytrid fungus and how it is causing amphibian deaths globally. Many theories exist as to where chytrid originated and how it spread, but regardless of the answer to those questions, the fungus has now been found in almost every environment all over the world. Removing the fungus from the environment does not seem to be a possibility since it has become so widespread, as this could potentially damage the ecosystem and other lifeforms in it. So, the question becomes: How do we save the frogs?

Frogs are most susceptible to chytrid when they are young – tadpoles and juveniles have the highest death tolls as a result of this fungus. The tadpoles of the three target species we are focusing on in Honduras (the exquisite spike thumb frog, the Cusuco spike thumb frog, and the mossy red-eyed tree frog) are especially sensitive to chytrid. The tadpoles have very strong mouths, which they need to be able to use as a “suction” to hold onto rocks in rapid waters of rivers. Doing so is vital to their survival, and as such, chytrid is particularly damaging to these animals. Chytrid is attracted to keratinized skin cells, which are found in the mouths of tadpoles. The resulting infection causes them to lose function of their mouths, which can cause them to have trouble eating and difficulty with “suction” onto rocks. The loss of this suction can cause tadpoles to be swept downstream into unsafe waters.

Photo by Jon Kolby

This is all devastating; however, we came up with an idea for how we might be able to help.

What if we could remove tadpoles from the stresses of the environment during the stage in which they are most sensitive to chytrid? Using our skills and expertise in caring for amphibians, we might be able to nurture them in a pristine environment. The lack of stress would potentially prevent symptoms of the fungus from appearing. Alternatively, if symptoms did arise, caretakers could treat the fungus to assure survival. Then, when the animals have reached adulthood, they could be returned to the wild.

This method of rearing animals through sensitive stages is called “head-starting”, and is a method frequently used with amphibians. It has shown to be beneficial in instances just like this, where adults survive better than offspring. Long term, the hope is that the increased population from the head-started animals would be enough to booster the population into stability.

Photo by Jon Kolby

The Detroit Zoological Society and the Honduras Amphibian Rescue and Conservation Center are ready to start head-starting animals. Facilities have been built in Honduras in order to provide tadpoles a safe place to live and grow until they are ready for release. In an upcoming entry on the DZS Blog, we will go inside the rescue center’s facilities and show you what the tadpole rearing experience will look like!

– Dr. Ruth Marcec is the director of amphibians for the Detroit Zoological Society and oversees the National Amphibian Conservation Center at the Detroit Zoo.

Notes from the Field: Saving Tree Frogs in Honduras – Part I

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The Detroit Zoological Society is collaborating with the Honduras Amphibian Rescue and Conservation Center to preserve three species of endangered frogs from the cloud forests of the Cusuco National Park in Honduras. The rescue center is an in-country facility that aims to re-populate these three endangered species through programs such as head starting, captive breeding, habitat protection and community outreach.

Amphibians all over the world are suffering extinctions, and the species in the Cusuco National Park are at a particularly high risk. There is a fungal disease, called chytrid, that is causing drastic population declines amphibians globally. Chytrid fungus has been particularly devastating to amphibians that live at higher elevations in the tropics, because the fungus thrives in lower temperatures and high humidity. This fungus likes to live in keratinized skin cells, and because amphibians rely on their skin to breath and exchange nutrients, it can be very deadly. The Cusuco National Park is a protected area that is home to many rare amphibian species who, unfortunately, are subjected to this fungal disease. The Detroit Zoological Society is working with the rescue center to investigate how to help save these animals from extinction.

While there are many species of amphibians in Honduras that need help, we decided to start our mission with three “target species” of critically endangered tree frogs. Once we find the best way to help these species, we can apply what we learned to others locally. These three target species are the exquisite spike thumbed frog (Plectrohyla exquisita), the Cusuco spike thumbed frog (Plectrohyla dasypus), and the mossy red eyed frog (Duellmanohyla soralia). All three of these frogs have been found to have the highest infection rates with chytrid fungus in the Cusuco National Park and are at high risk of extinction. This spring, we conducted fieldwork in Honduras, visiting the natural habitat of the three target species to help gain a better understanding of their behavior. We were able to observe some never-before-seen behaviors of these interesting animals that will help us increase our chances of protecting them.

Before I get too carried away, let me introduce you to the three species!

Photo by Jon Kolby

Exquisite spike thumb frogs are the largest tree frog in the Cusuco National Park at approximately 4 inches long. These frogs are found exclusively in the small protected area of the park, and are listed as Critically Endangered by IUCN. The frogs get their name from the large boney projection that males have on the sides of their thumbs, called a prepollex. It is theorized this special appendage is used for male combat, but combat has not yet been observed in this species. Additionally, the call of these frogs has never been heard (or at least recognized) by human ears.

Photo by Jon Kolby

Cusuco spike thumb frogs also only live in the small protected region of the Cusuco National Park; they are also listed as Critically Endangered. This species also gets its name from a prepollex in the males. Cusuco spike thumb frogs are medium-sized, growing to about 2 inches. Their call is a “quack” noise, similar to a duck. When threatened, these frogs have been observed jumping into leaf litter and burying themselves, which is unusual behavior for tree frogs.

Photo by Jon Kolby

Mossy red-eyed tree frogs are the smallest of the three target species, at a maximum of about 1.5 inches, and are also listed as Critically Endangered. As tadpoles, they have a striking green sheen to them, and they perform an odd behavior. They will flip over on their backs to swim – bellies up – in the rapids of waterfalls. Mossy red-eyed tree frogs can be heard calling with a series of chirps and clicks.

The Detroit Zoological Society and the Honduras Amphibian Rescue and Conservation Center have a plan to save these amazing animals. I’ll be sharing more details about this plan in upcoming blog entries, so stay tuned!

– Dr. Ruth Marcec is the director of amphibians for the Detroit Zoological Society and oversees the National Amphibian Conservation Center at the Detroit Zoo.