Amphibian Conservation: Species in Crisis

Let’s focus our attention on the smallest residents living at the Detroit Zoo: amphibians. No other class of vertebrates has the ability to adapt and evolve as quickly in our ever-changing planet as amphibians. They have used every reproductive strategy and developed life stages influenced by environmental factors; they can be colorful, camouflaged and cryptic, regenerate limbs, and have been on Earth for the last 200 million years.

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Currently, amphibians are the most threatened group of animals in the world with 40 percent of all species at risk. This crisis is considered the greatest extinction event in history; it’s also the Earth’s sixth mass biological extinction. While previous mass extinctions have been driven by natural planetary transformations or catastrophic asteroid strikes, the current die-off can be associated directly with human activity. This epoch started when human activities began having a significant impact on the Earth’s ecosystems.

The Detroit Zoological Society (DZS) participates in Global Assessments, which provide a comprehensive inventory of the conservation status of biological species as well as a critical dataset for evaluating the health of key elements of biodiversity and identifying threats to their survival. Newly described species emerge yet extinctions are occurring at an even faster rate. Climate change is the most dramatic cause of declines, and it affects amphibians both directly and indirectly, as reproduction is dependent on temperatures and seasonal transitions. Low pond levels expose embryos to more ultra violet (UV) light and UVB radiation is harmful to many species. The shorter periods and earlier opportunities for breeding ultimately reduce the chances of success. Amphibians are also dependent upon water, which makes them vulnerable to desecration when ponds dry too quickly. But since amphibians rely on the environment, they also are excellent storytellers. They can help us determine where pollutants are and if there is misuse of habitat.

When the National Amphibian Conservation Center (NACC) opened at the Detroit Zoo in 2001, it was the first major facility dedicated entirely to conserving and exhibiting amphibians. The award-winning, state-of-the-art amphibian center is home to a spectacular diversity of frogs, toads, salamanders, newts and caecilians, many of which are the subjects of field research and part of cooperative management programs called Species Survival Plans (SSP). Amphibians selected for an SSP are generally threatened, endangered and sometimes even extinct in the wild. The DZS is actively involved in many of these programs, including for the Wyoming toad, Puerto Rican crested toad, Panamanian golden frog, crawfish frog and Mississippi gopher frog. Some amphibians bred at the Detroit Zoo have been released into the wild to boost endangered populations, and others require us maintaining a “captive assurance population” because due to factors in the wild, they cannot be released just yet. When it’s safe for these species to return to their native homes, we have a population ready to release. We have specially designed, bio-secure rooms that can hold each of these species so they won’t be exposed to other amphibians or anything else that may be harmful when they are released.

In addition to maintaining our captive amphibian population and our efforts in cooperative breeding programs, DZS staff participates in several field projects and research programs, offers citizen science training and provides support for wildlife rescues, including those from the exotic pet trade.

– Marcy Sieggreen is the curator of amphibians for the Detroit Zoological Society and oversees the National Amphibian Conservation Center at the Detroit Zoo.

Editor’s note: Marcy Sieggreen was the curator of amphibians for the Detroit Zoological Society from 2008 until her passing in 2016. The Detroit Zoological Society established the Sieggreen Amphibian Conservation Fund in Marcy’s memory to continue to advance the work she so passionately championed.

Notes from the Field – Scientific Research in Antarctica

As the only continent on Earth without a native human population – and with the harshest and most extreme climate in the world – Antarctica presents a unique, natural laboratory for scientific research. As challenging as the climate is, it is vital to understanding ecosystems and our impact on the planet.

Half a century ago, the governments of 30 countries collectively formed the Antarctic Treaty System to regulate this natural wonder as a scientific preserve. Now more than 50 research stations are in operation there, with scientists and their support staff numbering a few thousand during the austral summer when conditions are less severe. These include biologists, ecologists, geologists, oceanographers, physicists, astronomers, glaciologists and meteorologists. Even still, the vast majority of the white continent is still little known. Such is the case with the Weddell Sea. Its iceberg-filled waters are unpredictable and treacherous. This is the same sea that captured and crushed Sir Ernest Shackleton’s ship, the Endurance, 100 years ago.

We sailed the Weddell Sea as part of a recent expedition to Antarctica with scientists from the Detroit Zoological Society (DZS) and the Polar Oceans Research Group (PORG). World-renowned polar ecologist and penguin expert Dr. Bill Fraser, head of the PORG, shared his extensive knowledge on board, as he has done as consultant on the Polk Penguin Conservation Center. His research, which spans nearly four decades, operates out of the U.S. Palmer Station on Antarctica and focuses on the ecology of penguins and their habitats. Over the years, Dr. Fraser and his team have revealed a dramatic decline in Adelie penguins in this particular region of Antarctica – an 80 percent drop over the last four decades – due to shifting conditions and disappearing sea ice.

Sea ice remains an essential ecological variable in the Weddell Sea. Somewhat unlike the western Antarctic Peninsula (where the U.S. Palmer Station sits), sea ice is the platform for species survival. During our trek within this sea and our landings at Devil Island and Brown Bluff, we observed tens of thousands of Adelie penguins. The presence of sea ice in this oceanic basin appears to have had a positive effect on this species through processes that are not yet fully understood – but a theory is emerging. Unlike other areas, populations of Adelie penguins are either stable or increasing here. This is a very different situation from the western Antarctic Peninsula where sea ice is diminishing and Adelie populations are decreasing with it. A number of observational metrics including nesting density, chick condition and colony aspect were compared just a few days later during our voyage to the Palmer Station.

Visiting these locations within the Weddell Sea was also important to scouting potential field research sites. No other team or country is doing ecological research here. Given that the Weddell Sea is closer to any other region on the Antarctic Peninsula where sea ice still persists, it offers the most optimal situation to more closely study how sea ice impacts the ecosystem.

These donor-funded excursions are important to the Detroit Zoological Society’s wildlife conservation efforts. They have also yielded significant philanthropic support – our Antarctic expeditions have led to contributions of $15 million for the Polk Penguin Conservation Center, and this most recent venture also secured $67,000 for the Polar Oceans Research Group. While fundraising is an important goal, our relationship with Dr. Fraser and PORG is a compelling example of the power and impact of collaboration between the DZS and conservationists in the field.

– Ron Kagan is the executive director and CEO of 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.