Notes from the Field: Protecting Michigan’s Only True Venomous Snake

Michigan is the last stronghold for the massasauga rattlesnake – even though the species was listed as Threatened by the U.S. Fish and Wildlife Service, there are still several healthy populations throughout the state. The Detroit Zoological Society oversees the Species Survival Plan for this animal through the Association of Zoos and Aquariums (AZA). These comprehensive population management plans work to ensure the sustainability of healthy, genetically diverse and demographically varied captive animal populations.

The DZS and other facilities have participated in an ongoing research study at the Edward Lowe Foundation in Cassopolis, Mich., for the past 10 years. Recently, a team from the Detroit Zoological Society, which also included Jeff Jundt, curator of reptiles, and Dr. Wynona Shellabarger, a veterinarian for the Ruth Roby Glancy Animal Health Complex at the Detroit Zoo, participated in the 2018 Eastern Massassauga Rattlesnake Species Survival Plan annual meeting and conducted fieldwork in western Michigan.

This fieldwork consists of spending up to eight hours a day searching for snakes in their native habitat. When one is found, it is sent to a lab on grounds for a physical, which includes being weighed, measured, photographed, sexed, tagged with what is called a passive integrated transponder – if it didn’t have one already – and having blood collected. If the snake is female, it’s given an ultrasound to determine if she’s pregnant. Photographs of any distinct markings as well as the transponder can identify an animal throughout their life if they are located again. GPS data allows the snake to be returned to the exact spot where it was found earlier in the day.

All of the information gathered throughout the week helps draw a picture of the natural history of this species, guide best practices for the land management of the Edward Lowe Foundation and gauge the overall health of the individuals and the population. This year, even though the weather was not as cooperative as past years, the group was able to locate and conduct physicals on 36 snakes, 14 of which were new to the study. The DZS plans to continue leading this important research for years to come. To stay up to date on all things massasauga rattlesnake-related, follow the Species Survival Plan on Facebook.

Also, please join us as we celebrate all things that slither on World Snake Day, Monday July 16, in the Detroit Zoo’s Holden Reptile Conservation Center.

– Rae Karpinski is a reptile zookeeper for the Detroit Zoological Society.

Animal Welfare: A Compassionate Approach to Toad Conservation

Staff members from the Detroit Zoological Society’s (DZS) National Amphibian Conservation Center and Center for Zoo and Aquarium Animal Welfare and Ethics are collaborating to find out what toads like. By doing so, we can ensure we are providing for their welfare while they’re in our care and also contributing to the conservation of this species in the wild.

Wyoming toads (Anaxyrus baxteri), also known as Baxter’s toads, are considered extinct in the wild, and their numbers must be bolstered each year by reintroductions of individuals born and reared in the care of humans. They can be found in two locations within the Laramie Basin in Wyoming, thanks to efforts by the U.S. Fish and Wildlife Service and other dedicated organizations including the Detroit Zoological Society.

Wyoming toads were abundant until the 1970s when their numbers began to plummet due to the spraying of aerial pesticides, habitat alteration and the fungal infection caused by chytridiomycosis, which is decimating amphibian populations worldwide. By 1984, the species was listed as endangered and in 1993, that listing changed to extinct in the wild. That year, what were believed to be the last 10 remaining Wyoming toads were brought into a facility to safeguard them and begin a breeding program in the hopes of one day reestablishing the species in the wild.

The Association of Zoos & Aquariums started an official Species Survival Plan for the Wyoming toad in 1996, a program in which the DZS has been very active, including releasing thousands of toads hatched at the Detroit Zoo since 2001. Through the efforts of this collaborative breeding program, more than 1,500 Wyoming toads are currently believed to live in the wild.

Because breeding success continues to be a great concern for this species, the Wyoming Toad Species Survival Plan established strict guidelines for habitat setup at the participating institutions. The habitats are rather sterile to reduce the potential development of any disease processes and consist of a dry area typically made of PVC, a water feature, a basking lamp and a shelter. This type of setup was necessary to properly monitor conditions to promote higher survival rate and breeding success. Due to the success of the reintroduction program, new habitat parameters can be explored, providing the toads with a more stimulating environment.

It is important that we assess how this affects the toads and what preferences they might have. To that end, habitats are being created that provide the toads with a choice between the standard habitat and one that has more naturalistic elements, such as soft substrates, multiple shelters and water features of varying shapes and sizes. With the assistance of our current resident, Emilie Gupta, we will be studying the toads to determine if this choice is important to them. Providing animals with choices and agency – or control – over certain aspects of their lives has been proven to positively affect welfare in some animals. This research will augment what we know about amphibian well-being and will add a compassionate dimension to this conservation success story, in which ensuring the welfare of individuals is a critical part of protecting the species.

Dr. Stephanie Allard is the director of animal welfare for the Detroit Zoological Society and oversees the Center for Zoo and Aquarium Animal Welfare and Ethics.

Notes from the Field: Monitoring the Eastern Massasauga Rattlesnake

The Detroit Zoological Society (DZS) leads the Eastern massasauga rattlesnake Species Survival Plan (SSP), which is a comprehensive management plan through the Association of Zoos & Aquariums (AZA) that works to ensure the sustainability of healthy, genetically diverse and demographically varied captive animal populations. The DZS is also one of several organizations within the AZA that participates in a long-term study of a particular population of Eastern massasauga rattlesnakes in Michigan.

The Eastern massasauga rattlesnake is the mitten state’s only venomous viper, and is listed in Michigan as a species of special concern, which means it is threatened or endangered throughout its range. This SSP is a special one because each year, representatives from participating zoos attend a meeting in conjunction with an “in situ” study, which means that it takes place in the field.

This year marked our eighth monitoring a particular population of Eastern massasauga rattlesnakes in the southwest part of the state, and it was our best year to date – we found more than 100 snakes! This includes snakes that were found in previous years as well as newly identified individuals. The process involves gathering information on each snake in the field and then taking it to a lab where it is weighed and measured. We also determined if it is a male or a female and if female, whether it is pregnant (massasaugas give birth to live young). If the snake has never been found before, it is marked with a transponder tag – similar to those implanted in your pet dog or cat – so we can scan the animal and take measurements if it is found in the future. After the information has been gathered in the lab, the snake is then returned to the exact location where it was found.

Monitoring a seemingly healthy population over time gives us insight into natural fluctuations of the population size, male-to-female sex ratio, individual growth rates and reproductive success. As years goes by, the data will also begin to tell us life history data such as longevity of the species and how old animals remain reproductively active. All of this information assists the AZA zoos in how they manage the captive population as well as the state departments of natural resources in their management of the wild populations and the lands on which they are found.

– Jeff Jundt is the curator of reptiles for the Detroit Zoological Society and oversees the Holden Reptile Conservation Center at the Detroit Zoo.

Amphibian Conservation: Breeding Puerto Rican Crested Toads

April is an important time for the Detroit Zoological Society’s amphibian conservation programs. Three of the four animals we work with at the National Amphibian Conservation Center (NACC) that are a part of Species Survival Plans (SSP) are preparing to take part in precisely planned and scheduled breeding events. The outcome is the release of captive-born offspring into the wild to aid in the increase of their populations.

First up for the season is the Puerto Rican crested toad, Peltophryne lemur. The PRC toad, as we like to call them, has been part of a well-managed SSP since 1984. Habitat loss and competition from the invasive cane or marine toad (Rhinella marina) are believed to have been primary causes for the toad’s decline. Listed as critically endangered by the International Union of the Conservation of Nature (IUCN), collaborative efforts by the Associations of Zoos and Aquariums, U.S. Fish and Wildlife Service and the Puerto Rico Department of Natural and Environmental Resources have aided the recovery of this toad in the wild. More than 300,000 captive-bred tadpoles produced by 20 zoos have been released to the wild since 1982. Since the year 2000, the Detroit Zoological Society has produced more than 45,000 tadpoles for this program. In 2015, three clutches of eggs laid produced 22,571 tadpoles for release – the largest amount the Detroit Zoo had ever sent. Ongoing research and the creation and protection of pond habitats have also assisted in the recovery of this toad in its natural habitat.

You may be wondering what it takes to produce thousands of tadpoles from toads half the size of the palm of your hand. The breeding season starts with the assignment of four breeding pairs from the SSP. Each toad in captivity is identified and tracked using a studbook. Specialized software chooses pairs of toads that will produce the most genetically diverse offspring. By mid-March, we know who these eight toads are and we can begin preparing them for breeding.

Each toad must be easily identifiable – if you think all toads look alike you’ll be surprised to know that wart patterns and throat markings are very unique, although reading glasses are sometimes needed to make the proper ID. Toads are conditioned by slightly cooling and drying their environments out for a month-long period. A thermostat-controlled refrigeration unit keeps the toads cooled precisely at 66 degrees Fahrenheit. While the toads are “sleeping”, their primary zookeeper works diligently on preparing the breeding tanks where the pairs will breed and the eggs will develop. At this same time, veterinarians prepare a schedule of specialized breeding hormones that will further assist in ensuring that eggs are laid and fertilization happens at the right moment.

Upon their exit from cooling, they return to normal husbandry to warm up and eat for a few days. Breeding calls of male toads are played to encourage breeding behaviors. Males are first to go into the breeding tanks, followed hours later by the females. If all the preparation works, pairs of toads will be in amplexus – which happens when a male is positioned on top of a female and he squeezes her to encourage egg-laying – before we leave for the evening, followed by a morning of tanks full of eggs.

It takes two to three days for eggs to hatch and another couple of days for tadpoles to begin swimming around and actively eating. Tadpoles can be some of the hungriest creatures you will ever encounter. Keepers spend the next 10 days keeping them fully fed by offering them algae pellets, powdered diets and romaine lettuce sometimes three times a day. At the same time, all those foraging tadpoles create a lot of waste, so keepers spend the rest of their time keeping their water clean with frequent water changes.

During all of this, we keep a very important date in the backs of our minds – the last big event in our PRC toad breeding season. Any facility that breeds the PRC toad needs to ship them to Puerto Rico for release on the same date. The release of the tadpoles is timed with the season in which the tads would grow and develop the best in the wild. Tadpoles also need to be shipped at a certain age, before they get too big and begin to develop appendages.

Amphibian staff can spend well over 24 hours collectively counting and packing the tadpoles into Styrofoam-protected shipping boxes. Heavy-duty fish shipping bags are used, doubled up and filled with oxygen to keep tadpoles healthy and safe on their trip to Puerto Rico. Approximately 24 hours later, they will reach their new home in a pond located in a well-protected forest in Puerto Rico. As they develop and grow, they will add to the wild population and one day, hopefully, participate in creating many more thousands of tadpoles!

Rebecca Johnson is the associate curator of amphibians for the Detroit Zoological Society.

Education: What is a Species Survival Plan?

Red pandas Ta-Shi and Shifu have produced several adorable cubs at the Detroit Zoo, most recently little Tofu. North American river otters Whisker and Lucius have sired a couple pups and reticulated giraffes Kivuli and Jabari are well known for their now 13-foot-tall calf Mpenzi. Pairings like these and the offspring that follows are not by chance; each is carefully planned out and managed through what is known as a Species Survival Plan (SSP).

The 230 accredited zoological institutions that comprise the Association of Zoos & Aquariums (AZA) work together through these cooperative management programs to ensure genetically healthy, diverse and self-sustaining populations of threatened and endangered species. More than 450 species are apart of an SSP throughout zoological institutions in North America, overseen through a comprehensive population management system, which includes a Studbook and a Breeding and Transfer Plan. Each of these identifies population management goals and makes recommendations to ensure the sustainability of a healthy, genetically diverse and demographically varied animal population.

The Detroit Zoo has individuals from 98 of these species under its care, including 38 birds, 30 mammals, 24 reptiles, four amphibians, one fish and one invertebrate. Many of these species are animals that require immediate attention to save the remaining wild populations. Our cooperative breeding efforts have proven extremely successful – for example, the Detroit Zoo has been credited with restoring the population of a Tahitian land snail called partula nodosa, once extinct in the wild. Additionally, in May of last year, 22,571 Puerto Rican crested toad tadpoles bred at the Detroit Zoo were released into the wild of Cabo Rojo, Puerto Rico. In 2014, a record 3,945 Wyoming toad tadpoles bred at the Detroit Zoo were released into the wild. This long-running effort was previously recognized as No. 1 on the AZA’s list of the Top 10 wildlife conservation success stories.

AZA institutions and partners work together to carefully monitor SSP species both in the wild and in zoo populations. Organizations will often move SSP animals to other zoos and aquariums so they can mate with individuals to ensure a long-term healthy future for the species. Breeding recommendations are made with consideration given to each animal’s social and biological needs as well as transfer feasibility.

Be sure to look for the SSP logo on animal signage as you explore the Detroit Zoo on your next visit. Each time you see the logo, you’ll know that there are countless individuals working at zoos, aquariums and in the field around the world to do everything we can to save and rebuild the remaining populations of these species.

Notes from the Field: Saving the Wyoming Toad

For the past few summers, I have traveled to Laramie, Wyoming for the Wyoming Toad Species Survival Plan (SSP) meeting, which is an effort by the Association of Zoos & Aquariums (AZA) to cooperatively manage species populations within accredited zoos and aquariums.

First, I fly into the Denver International Airport, which is followed by a 140-mile road trip to Laramie. The trip is full of spectacular views of mountains, canyons, vast plains, huge clouds and pronghorn antelopes. Sometimes I drive the distance alone but this year I made the trip with three colleagues from different zoos. Each of us is a representative for our respective institution, all sharing the same goal of saving one of North Americas most endangered amphibians, the Wyoming toad.

After a stop for groceries and gas, we arrived at our destination for the next five days – a cabin in this remote area of Wyoming. We’re joined there by most of the other members of the SSP – this year, 10 people stayed at the cabin. Most of us have known each other for some time, so sleeping together in a room full of triple-layered bunk beds seems like a week at camp with old pals. But it’s far more than summer camp – we take part in discussions and updates on a number of important topics such as husbandry, health, management, fieldwork and research on this toad.

The next morning, representatives from the U.S. Fish and Wildlife Service (USFWS) arrived along with the AZA SSP coordinator to begin the meetings. Besides the zoos and aquariums involved, there are two USFWS facilities in Wyoming that hold, breed and release the toads. Many important topics are discussed with the last being choosing captive breeding pairs for 2016.

The Detroit Zoological Society (DZS) breeds these critically endangered Wyoming toads at the National Amphibian Conservation Center (NACC). Since 2001, the DZS has released more than 6,500 Wyoming toads into the wild as tadpoles, toadlets and adults. In 2007, the Detroit Zoo earned the highest honor on the AZA’s list of the Top 10 wildlife conservation success stories for that year.

The population of toads is maintained in special bio-secure off-exhibit rooms of the NACC. We have enough room to breed four pairings each year, and any tadpoles produced by the pairings are shipped out to Wyoming for release into protected wetlands in efforts to create self-sustaining populations.

Like each of the organizations present, I brought detailed notes on every adult toad in our resident population so that the best pairs could be chosen. Captive Wyoming toads need to be of ideal weight and health to take part in a month-long hibernation, followed by a June breeding event. Through the AZA, there is an identified “studbook keeper” who matches toads pairs that are least related and most likely to produce offspring that will be the most genetically fit.

On the second day in Laramie, we received training for the USFWS field surveys. Field surveys are done three times during the warmer months of the year around Mortenson Lake. This lake is the last known area the Wyoming toad lived before it was removed from the wild to protect the species from extinction. It is also the site of past and present releases of captive-produced tadpoles and toadlets. Present-day releases are more protected and provide several topics for research. Members of the SSP have been assisting with the mid-summer field surveys for more than five years and the training is just the beginning of a two- to three-day process to see how many Wyoming toads can be found around the lake.

The third and fourth day of my stay is spent almost entirely out in the field surveying for toads around the lake. Teams of two or three people carry backpacks full of equipment for data collection. Each plot must be surveyed in a specific allotted amount of time and by walking in an S-shaped pattern. Toads can be found hiding under grass, sitting on hard-packed sandy areas or swimming near the shore of the lake. If a toad is located, the timer is stopped, and data collection starts. Toads are photographed for identification, weighed, swabbed for disease testing and, if large enough, “microchipped”. It is particularly exciting when an older toad or a toad with an existing microchip is found. This usually means the toad has survived one or more very cold winters and may potentially breed in the lake.

Weeks later, back at the Detroit Zoo, I receive the compiled results of the survey. This year, we located and collected data on 224 toads – 129 toadlets that were captive-born and released into the lake this spring; 29 toads that were captive-born, released last year and survived the winter; 33 adult females and 33 adult males. Until next July, go toads!

– Rebecca Johnson is the associate curator of amphibians for the Detroit Zoological Society.

Notes from the Field: Two Weeks in the Panamanian Jungle

Recently, I found myself trekking through the jungle, holding a machete, in search of the perfect piece of wood. This wasn’t a typical day of work for me with the Detroit Zoological Society (DZS) – I’m usually found in the National Amphibian Conservation Center (NACC) at the Detroit Zoo, changing filters, cleaning misting lines and feeding tadpoles. But on this particular day, I was in El Valle, Panama, a small town situated in the valley of an extinct volcano; the historic home to the Panamanian golden frog (Atelopus zeteki), a species that is critically endangered in the wild.

The DZS has maintained a breeding population of Panamanian golden frogs at the NACC since the year 2000 as part of the Association of Zoos and Aquariums’ Species Survival Plan, a cooperative management program that ensures genetically healthy, diverse and self-sustaining populations of threatened and endangered species. Since I personally care for and breed this delicate species at the Detroit Zoo, it was truly awe-inspiring for me to travel to Panama; to see and experience the tropical cloud forest habitat that was home to the golden frog until the late 1950s, when the last sightings were reported in the area.

Like many amphibian population declines worldwide, the threat to the Panamanian golden frog is a multi-pronged, human-induced sucker punch of climate change, de-forestation and over-collection for the pet trade. Also, a very serious parasitic fungus known as Batrachochytrium dendrobatidis or “chytrid Bd” [ki-trid] became present in the area. This fungus thrives in the environment of a cloud forest and caused a dramatic decline in amphibians through the region.

Despite the thrill of viewing some amazing wildlife on our walk through the Panamanian jungle, I wasn’t there to enjoy the scenery. My purpose in traveling to El Valle was to assist the limited staff at the El Valle Amphibian Conservation Center (EVACC), a small conservation center dedicated to breeding and researching the country’s most endangered amphibians, as well as educating the community in Panama about the amphibians in the area.

For two weeks, I trained the staff at EVACC on habitat design and maintenance. I shared techniques for designing water features, drilling enclosures for bulkhead placement and “propping” habitats – gathering supplies like logs, plants and rocks to create a naturalistic environment. One day was dedicated to removing and replacing an old “roof ” of a habitat planned for golden frogs, which was the size of a living room. Other days involved finding things like sticks, logs and foliage to prop the habitats, and since all of the animals were from the surrounding area, most of what we were collecting could be found and disinfected within the grounds of the conservation center.

The EVACC’s newly designed habitats would be playing an important role in the “Golden Frog Day” in El Valle, a celebration of the magical amphibian that once lived and thrived among the misty forests of the mountains. Without public support in its country of origin, there could be no future for this animal. With newly renovated habitats and the beauty of this vibrantly colored amphibian, visitors to the center can begin to understand the value of this species and the power it holds as members of the community work to conserve it.

A true reward for all of this hard work and training came several days after leaving Panama, when I received an email from EVACC staff informing me that they had drilled their first tank and were using techniques that I taught them to install a new waterfall feature. While I had ditched my machete and my head lamp, no longer needing to trek into the jungle for my work with the Panamanian golden frogs at the Detroit Zoo, I know that the work we are doing some 4,000 miles away from their home is just as critical to the survival of this incredible species.

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