Animal Welfare: Sounds and Sights in the World of Rhinos

Detroit Zoological Society (DZS) staff are studying how the Southern white rhinoceroses who live at the Detroit Zoo respond to different types of stimuli and how this may influence their welfare. Rhinos have a well-developed sense of hearing and can hear noise frequencies lower than the average human can. Sounds may also be up to twice as loud to them as they are to us. This means that the way the world sounds to a rhino is very different than what we hear. In comparison to their auditory capabilities, their eyesight is believed to be relatively poor. This may mean that they are less able to discern objects around them and that things that happen in their environment might be more startling to them. As our sensory abilities differ from those of rhinos, we have to work to increase our understanding of what environmental factors are meaningful to them. The question isn’t just what is it like to be a rhino living at the Detroit Zoo, but what is it like to be a rhino at the Detroit Zoo experiencing great welfare?

We began observing Tamba and Jasiri in 2017, both inside their building and in the outdoor habitat. We explored differences in their behavior between these spaces and in conjunction with the number of visitors present. We noted that the rhinos showed increased signs of positive welfare when presented with more choices in their visual and auditory environment. Based on this information, we designed a study to investigate specific factors that may affect the well-being of the rhinos inside their building, including stimuli from visitors. In this space, noises are amplified and the rhinos are in closer proximity to visitors, compared to their outdoor habitat.

The study took place in four phases between December of 2017 and February of 2018. During the first phase, no changes were made, allowing us to obtain baseline behavior and hormone levels for the rhinos. This gives us a point of comparison to assess any effects of changes we make. In the second phase, we increased the distance between the rhinos and visitors using a rope barrier. The larger buffer space changed both the visual and auditory environment for the rhinos by having visitors further away without reducing the amount of space available to the rhinos. During the third phase, we added large sound abatement panels, which reduce noise levels through added insulation, along the back wall of the visitor area and in the space occupied by the rhinos. Finally, in the last phase, we installed additional visual barriers, providing the rhinos with the choice to block their view of visitors.

During each phase, we collected behavioral data and fecal samples daily. Changes in behavior and concentrations of corticosterone in the fecal samples help us decipher how the rhinos responded to the changes we made. We are currently analyzing all of this data, and so far, it appears that both rhinos showed increased behavioral diversity – which is a measure of the variety and frequency of behaviors – with the modifications that were made. Animals demonstrating higher behavioral diversity are believed to be experiencing better welfare as they are more motivated to engage in a larger number of behaviors. This may be a reflection of an environment that better meets the animals’ needs.

For Jasiri and Tamba, one of the behaviors that increased in frequency is what we call object manipulation. The rhinos spend time interacting with various objects provided to them to stimulate them both physically and mentally. Both rhinos definitely like their “back scratcher” and Tamba is partial to making bells chime! This may seem counterintuitive if noise levels can impact their well-being, but it really is about choice. Tamba is in control of making those sounds – when and for how long – which is very different than having to listen to sounds you don’t enjoy. Jennifer Hamilton, DZS animal welfare programs coordinator, explains it really well. As she says, imagine that you are at a stoplight and someone in the car next to you is blasting music that you don’t like – how does that make you feel? However, when a song you do like comes on the radio, you might just turn up the volume. The good thing is that Jasiri doesn’t seem to mind any of Tamba’s “concerts”! The rhinos also spent more time investigating their indoor habitat, which they do by smelling and moving around more. This is a space they know well, so this increase in activity isn’t due to novelty. This may instead be telling us that they were more comfortable in their habitat. We also noted a new social behavior we had not previously observed.  Rhinos often spar with one another, locking horns to determine dominance. Tamba and Jasiri would rest while standing with their horns together, without any other movement typical of sparring. Although we aren’t sure what this “horn holding” means, we are interpreting it as a friendly and positive social behavior. Once we have the full results, we will be better informed about environmental features that enhance rhinoceros welfare. When we apply what we learn, we can have a direct impact on making sure Tamba and Jasiri are thriving.

– 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.

Trim Your “Waste” at Home

Americans produce a staggering 258 million tons of garbage every year, with each individual throwing out nearly 4.5 pounds per day, according to the American Society of Civil Engineers’ 2017 Infrastructure Report Card. What’s even more mind-blowing is the fact that Michiganders are among the biggest culprits – our recycling rate is just 15.3 percent, according to the Michigan Department of Quality. We can do so much better than that.

Solid waste has contributed greatly to the rising levels of greenhouse gas emissions, which is having catastrophic impacts on wildlife and wild places around the world. Moreover, many creatures mistake unnatural waste as food and can end up swallowing or becoming trapped in it, which often leads to serious injuries or deadly consequences.

If we all did our part to be more mindful in the choices we make in our daily lives – including reducing the amount of waste we produce – we could lighten our impact on Earth. Consider the following actions:

  • Switching from single-use items (disposable water bottles, cutlery, plates, etc.) to reusable items such as wood, metal or glass.
  • Recycling items properly to prevent them from sitting in a landfill.
  • Only purchasing foods you know you will eat.
  • Choosing a reusable fabric bag for grocery or leisurely shopping.
  • Opting out of receiving magazines you no longer read, or junk mail.
  • Composting food waste to naturally fertilize your soil.
  • Reusing items you already have. For example, save that old pickle jar to store loose change!

An important aspect of the Detroit Zoological Society’s mission is to lessen our impact on the environment and create a more sustainable future. To do this, we have made it a priority to reduce the waste we generate at the Detroit Zoo and Belle Isle Nature Center. As a part of our award-winning Greenprint initiative, we are keeping 60,000 plastic bottles out of the waste stream annually by no longer selling bottled water on Zoo grounds. We are also selling reusable animal-themed bags in lieu of providing plastic bags at Zoo concessions. We do not provide plastic straws with fountain beverages, and we have made the conscious effort to use eco-friendly cutlery at the Arctic Café, which is one of only four restaurants in Michigan that is “green-certified”. In an effort to turn waste into energy, we were the first zoo to construct an anaerobic digester, which converts more than 500 tons of animal manure and food scraps annually into renewable energy to help power the Zoo’s Ruth Roby Glancy Animal Health Complex. The byproduct from the digester is used to create compost called Detroit Zoo Poo, which is available for purchase at Zoo concessions.

Our annual 21-and-older fundraising event, Sunset at the Zoo, is part of this zero-waste journey. The VIP Party and champagne welcome have been waste-free for the past two years. We also have volunteers stationed at various locations throughout the Zoo during the event to help guests learn what items that might otherwise go in the trash can be recycled or composted.

Becoming a waste-free organization is a journey, and these are just a few steps we’ve undertaken, with many more to come.

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.

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

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.