Month: June 2016

Education: Animal Nightlife

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As the summer sun rises and sets, animals notice. Many of the animals that live at the Detroit Zoo are diurnal, meaning they are most active during the day. Gorillas, chimpanzees, butterflies, squirrels and camels are examples of animals that are most active during the day. As the sun sets, they prefer to settle in and sleep the night away.

Nocturnal animals include owls, bats, beavers, aardvarks and crickets, to name a few. That’s why you can hear crickets singing during summer nights and why most of us don’t see owls and bats hunting in the dark skies. Nocturnal animals have special adaptations such as enhanced hearing, eyesight and/or sense of smell that help them navigate after dark to find their prey.

Some animals are crepuscular, meaning they prefer to be active in the twilight hours of dawn and dusk. Deer, red pandas, fireflies and many moths prefer the cooler hours of the day, venturing out while many larger predators aren’t as active.

The Detroit Zoo follows a diurnal schedule; it’s open when humans are most active during the daytime hours. However, there are opportunities for glimpses into the animal dusk- and nightlife. Wild Summer Nights are held on Wednesday evenings in July and August. The Zoo is open until 8 p.m., featuring crepuscular and nocturnal animals, and live bands in the Main Picnic Grove. Youth in first through sixth grades can sign up to participate in Twilight Trails, the Summer Safari Camp evening adventure, to explore animals at dusk and participate in citizen science studies of fireflies or investigate animal adaptations.

 

You can also explore crepuscular and nocturnal animal life in your own backyard or neighborhood. Watch for fireflies as the sun sets, or rabbits as they search for food in your lawn. Hang a white sheet and shine a light on it, come back an hour later and see what insects have landed on it.

Enjoy the warm summer evenings and all the amazing things they have to offer!

– Claire Lannoye Hall is a curator of education for the Detroit Zoological Society.

Notes from the Field: Monitoring the Eastern Massasauga Rattlesnake

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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.

Notes from the Field: Wolf-Moose Project on Isle Royale

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Isle Royale is a remote wilderness island in northern Michigan, and at more than 40 miles long, it is the largest island in the largest Great Lake: Lake Superior.

I recently spent some time on Isle Royale working on a conservation research project called the Wolves and Moose of Isle Royale, along with Brian Manfre, a mammal department supervisor for the Detroit Zoological Society. Moose first came to Isle Royale in the early 1900s; wolves joined in the 1940s after crossing an “ice bridge” from Canada. For more than 50 years, the wolf-moose research project has studied the predator-prey dynamics of these species, making it the longest continuous study of any predator-prey system in the world. I was very eager to see the island and participate in the work first-hand.

Unfortunately, the wolf population at Isle Royale has dropped to only two closely related individuals, and the project now focuses on how the moose population is responding to reduced wolf predation. There is a proposal to reintroduce more wolves, but this is a complicated issue, in part because Isle Royale is also a National Park. The National Park Service will decide on this proposal in the fall of 2017.

Brian and I were joined by eight others working on this project. In addition to looking for moose bones to study the moose population, our team would also be investigating the presence of wolves at two previously used wolf dens. We set off together on a four-hour ferry ride from Copper Harbor to Isle Royale, and reported to the Bangsund cabin, an old fishing cabin that was built in 1926 and has served as the base for the project since 1959. We loaded our backpacks with hearty camp fare such as oatmeal, cheese, peanut butter and other supplies for the week, and then took a short boat ride to our departure site. After a 2-mile hike, we set up the first camp.

We camped at several different sites on the shores of Lake Superior and several inland lakes, and soon got into a routine of cooking, cleaning and filtering drinkable water at the camps. We were fortunate to have very pleasant weather. There was frost one of the first nights, but later in the week it warmed up enough for black flies to pester us.

On a usual day, we would hike 2-3 miles on-trail and then walk another 3-5 miles off-trail more slowly looking for moose bones. It was difficult at times, as we were going through dense forest, up and down ridges and through swamps. When a moose bone was spotted the requisite, “Bone!” was shouted out, and everyone would converge on the site to look for more bones. We were happy to find any bones at all, but skulls and teeth were especially prized. When cut in a cross section, the rings of dentin in the teeth can be counted to estimate the age of the moose – similar to counting tree rings – which can provide important information on the moose population. We can also examine vertebrae for signs of arthritis: Many of the moose at Isle Royale have been found to live longer and develop more arthritis than moose in areas with more predators. While it was a thrill to find these moose remains and evidence of wolves chewing on the bones, it was even more exciting to visit the old wolf dens. Unfortunately, there was no evidence of recent wolf use but we did find approximately one-week-old wolf feces along a trail nearby.

After a week, we returned to the Bangsund cabin with heavier packs than we left with, as they’d been loaded with moose skulls and other bones. We enjoyed a shower via bucket and ladle and then feasted on lasagna, wild rice casserole and a very welcome salad. We told stories and sang songs – it was a fitting celebration for a meaningful contribution to the project.

If you’re interested in participating in the wolf-moose study, visit this website.

– Paul Buzzard, Ph.D., is the director of conservation for the Detroit Zoological Society.

Animal Welfare: What, How and Why

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I have written a number of blog entries on the animal welfare research projects we are conducting through the Detroit Zoological Society’s Center for Zoo Animal Welfare, and how collaborations enable us to move forward with many of the initiatives we undertake. Let’s now go back to the basics and explore what animal welfare is, how we go about evaluating the welfare of individual animals, and why this is fundamentally important.

The Association of Zoos & Aquariums’ Animal Welfare Committee defines animal welfare as an animal’s collective physical, mental and emotional states over a period of time, and is measurable on a continuum from good to poor. Although there are a number of other definitions available, the main factors remain consistent: Welfare is measured at the level of the individual animal, it encompasses all aspects of an animal’s life, and it can change over the course of time. The goal for anyone working with and around animals is to ensure that they each experience good welfare.

Going back many decades, people have long been concerned with the welfare of animals. In the 1960s, the Five Freedoms model was developed, originally as a means to assess the welfare of farm animals. This model states that animals should experience freedom from thirst, hunger and malnutrition, freedom from discomfort, freedom from pain, injury and disease, freedom from fear and distress, and freedom to express normal behavior. Since its initial development, this model has been applied in a variety of settings, including in zoos. However, the Five Freedoms model can be improved upon, as it is focused on minimizing negative states rather than also promoting positive welfare. Additionally, some of what is stated can be counter-productive to an animal’s survival. For example, if an animal never experiences thirst, then it may never drink, and this would not be a good thing. Therefore, the absolute freedom from some of the experiences is not even feasible. Rather, the important factor is ensuring that the resources necessary to perform the associated behaviors are available.

More recently, the Five Domains model was created, which delineates how nutrition, physical health, behavior and the environment (both physical and social) feed into an animal’s emotional state. The outcome is the individual’s welfare status. For example, if an animal is hungry but does not have access to food, this will result in a feeling of hunger, which will be a negative factor in the overall welfare status of that animal. If an animal is able to express natural behaviors, he or she will experience satisfaction, which is a positive emotion and contributes to positive welfare. All physical influences are taken into consideration as well as how they impact the internal, emotional state of the animal, in order to assess overall well-being.

Assessing welfare is a complex process that requires an understanding of the needs of a species and an individual as well as experience with scientific methods. It also typically includes multiple types of measures such as behavioral and physiological indicators. One can begin by evaluating what is made available to an animal, such as the physical space, the type of food presented and the social opportunities provided. This kind of assessment is known as a resource-based assessment, as it focuses on what we provide to the animals. To truly understand how an animal is faring, however, we also need to understand how they respond to their environment, and as such, conduct animal-based assessments. In our case, we usually observe how animals are interacting with their physical environment, with one another if they are a social species, and we utilize various physiological measures such as body condition, overall health and even hormone levels.

In order to ensure animals living in zoos are thriving, we need to understand what matters to them and that requires us to figure out how to “ask” them. Using existing methods and developing new ones to assess welfare is critical if we are to make evidence-based decisions for caring for animals. By letting animals tell us what is working and what needs to be improved, we are making their welfare a priority, and this is the ultimate responsibility we have to each and every animal living in the care of humans.

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

Amphibian Conservation: Crawfish Frogs in Crisis

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What is the best way to repurpose a basement in one of the buildings at the Detroit Zoo? Turn it into an amphibian’s paradise!

Amphibians across the globe are in crisis, with populations declining rapidly due to climate change, habitat destruction and a disease called the chytrid fungus. In an effort to reverse this trend for the crawfish frog (Lithobates areolatus), which is listed as Endangered in the state of Indiana, the Detroit Zoological Society (DZS) partnered with the U.S. Fish and Wildlife Service, the Department of Natural Resources and staff at Indiana University. In 2013 these entities began a repatriation project, which is an effort to return a species to its natural habitat. This involved the collection of egg masses from grasslands in Indiana, which were then transported to the Detroit Zoo, where staff raised them until they were almost froglets before releasing them back into the wild.

The crawfish frog can lay egg masses with as many as 5,000 eggs. That might make one wonder how these animals could be endangered, right? Well, even if all of those eggs hatched into tadpoles, less than one percent of those tadpoles would ever make it out of the water. Tadpoles are an easy prey for a wide variety of animals including birds, fish, mammals, frogs and even larger tadpoles. And even fewer tadpoles would make it far enough into adulthood to breed. This shows how vulnerable the tadpole stage is in a frog’s life, which is why we focused our efforts on this stage.

We knew what we needed to do, but where is there enough room for thousands of tadpoles at the Detroit Zoo? How about right under the noses of Jasiri and Tamba, two Southern white rhinos! Not directly under them, since 12,000 pounds of rhino would be harmful to a tadpole, but rather in the basement of their indoor habitat. It took a lot of hard work from staff, but the space was eventually turned into a fantastic temporary home for crawfish frog tadpoles. Some of their luxury items include manufactured ponds with an automatic rain system, spotlights and temperature control systems – and of course, plenty of food.

In April, the crawfish frog egg mass is transported from Indiana to the Detroit Zoo in a cooler. We take this egg mass right down to the basement where it is placed in water. In a couple of weeks, tadpoles start to emerge, which are then counted and moved into long pond-like pools. We raise these newly hatched tadpoles for about three months, with the amphibian department staff feeding and cleaning them daily. It takes hours to care for the tadpoles each day, but it is all worth it in the end when they are driven back to Indiana and released. The total number of tadpoles varies from year to year, but since this project started in 2013, the DZS has released a total of 10,411 tadpoles back into the wild.

While wild tadpoles have less than a one percent chance of survivability, we were able raise that to an astounding 99 percent in 2014 and 2015 for these “basement” tadpoles. That’s because they don’t need to worry about predators, disease, lack of food or pollution. This lets them get a good head start on life – but we don’t make it too easy for them. Otherwise, they wouldn’t know what to do once they got back to the wild. So before they fully metamorphose – or turn into frogs – they are taken back to Indiana and released into the ponds. Since some frogs lead a “double life” – aquatic and terrestrial – they are able to finish their aquatic life stage in enclosed repatariums, or screened-in containers, that allow protection before they are released as full frogs in the environment in which they will live. This method works well and provides exposure to the environment they will be living in before they become too accustomed to the luxury of the rhino basement.

The DZS crawfish frog conservation project requires long hours, but it is also the best time of the year as a member of the amphibian department staff. Seeing how the DZS can make a positive impact on this species and the ecosystem is very rewarding.

– Michael Andrus is an amphibian department zookeeper for the Detroit Zoological Society and works in the National Amphibian Conservation Center at the Detroit Zoo.

Veterinary Care: The Evolution of Zoo Vet Resources

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I’ve been a practicing zoo veterinarian for 25 years; the last 20 of which have been spent here at the Detroit Zoo. Things have changed so much over the years, especially as it relates to the resources that are available to zoo and wildlife veterinarians as well as the technology we use to share information.

My first “real” job as a zoo veterinarian was at the Potawatomi Zoo in Indiana. I was the zoo’s first full-time veterinarian, and had to build the veterinary programs from scratch. I was a brand-new vet, full of ideas, and the only one at the zoo. It was a fun challenge and I had a lot to learn.

It was a very different time. When I first started I didn’t have a computer that was my own – I shared a very old model with our animal staff that did not have an internet connection. There was no email available back then; in order to reach out to someone for feedback or advice, you had to talk to them on a phone (that was connected to the wall!) The internet was not yet flush with information about zoo medicine, and most publications had to be rooted out of university libraries or actually found on your bookshelf.

So I made a lot of phone calls, talked to people at meetings, eventually sent a lot of emails, and connected with people on “listserves”. Some of my most valuable connections were within a group called the Midwest Regional Zoo Vets. This group started gathering soon after I started working in Indiana, and I very happily joined their ranks. It was a small group at first; five to seven people meeting to talk about anesthesia challenges and vaccine programs and sharing a spaghetti dinner made together in the hospital kitchen. I was the newest, youngest veterinarian in the group and found it invaluable to have this group as a resource.

Things have changed over the years. Electronic resources and connections make it much easier to keep the latest research at our fingertips and obtain feedback from other experts in our field. Despite all these resources, it’s still incredibly valuable to gather together and talk about the challenges we face. I’m happy to report that the Midwest Regional Zoo Vet group is still going strong after more than 23 years, and for most of these I’ve been the organizer and chairperson. We meet twice each year, rotating our locations between a dozen zoos in Ohio and the surrounding states. We have been able to maintain the intimacy of those first, small, cozy meetings, even though our last meeting was 30 members strong.

We talk about all kinds of things, from parasites to grief management, nutrition to radiology. We also often share clinical cases and invite outside experts to join in on the discussion. We talk about the cases that stump us, share our amazing success stories, and discuss our failures. There is no question that can’t be asked, no problem too trivial. I always learn so much more than I expect at our meetings – it’s fantastic! Zoo veterinarians are some of the most generous, dedicated people I know, and bringing my colleagues together to help provide the best possible medical care to animals is extremely rewarding. I’m proud to be part of a profession that feels like family!

– Dr. Ann Duncan is the Director of Animal Health for the Detroit Zoological Society and oversees the Ruth Roby Glancy Animal Health Complex.