As you walk through The Detroit Zoo, you may notice a lot of trees (follow along on our Trek). Trees are essential to the health of people, animals and the planet, which is why we are committed to taking steps to reduce our carbon footprint by adding even more to our lush grounds.
The Detroit Zoological Society (DZS) pledged to add a total of 2,000 trees by the end of 2022 to our campuses and in Metro Detroit communities. The average tree absorbs 48 pounds of carbon dioxide (CO2) and 1,673 gallons of storm water every year. Adding 2,000 trees (to the 7,000 trees currently growing at the Detroit Zoo), will make a big difference for nearby communities by helping to improve air and water quality. We have partnered with ReLeaf Michigan to help us organize group planting projects across Metro Detroit.
In 2021, the DZS planted 641, and we have full confidence in our ability to plant our total goal by the end of this year. Most recently, Oakland County planted five trees donated by the DZS in celebration of Earth Day 2022.
We are well on our way to achieving our goal of making the world a greener place through sustainable practices such as tree planting.
In addition to other environmental benefits, trees and other vegetation reduce heat island effect (urbanized areas experiencing higher than average temperatures) by providing shade. According to the EPA, shaded surfaces may be 20–45°F cooler than the peak temperatures of unshaded materials. The benefits from trees don’t stop there – they also provide shelter and food for birds, insects, and other critters such as squirrels. These animals then disperse the trees’ seeds, allowing new saplings to grow.
We are meticulously selecting a variety of species of trees to add biodiversity to our campus, as well as focusing on native species, browsable trees (clippings that make great snacks for the animals who live at Detroit Zoo), habitat value (for example, birds are attracted to oak trees), and resistance to climate change.
Our tree planting initiative is only one of the steps we are taking to create greener future. The DZS has developed a unique, green roadmap called the Greenprint. This evolving plan guides our operations and is the plan by which we refine and improve our facilities and daily practices, develop new policies and programs and improve green literacy and action in our community.
View our Shades of Green guide to learn more ways in which you can help lighten your impact on the Earth and the animals that we share it with.
Many of our older guests at the Detroit Zoo and Belle Isle Nature Center can likely remember a time when they looked up and saw a sea of stars peppered across the night sky, clear enough to count the constellations.
Today, things are different. As populations and industry have grown, artificial light has seeped into our night sky to the point where many of the younger generation have never seen a truly dark sky.
This month, the Detroit Zoological Society (DZS) is raising awareness around this unfortunate phenomenon by helping our guests understand how they can protect our naturally dark night skies — and, in turn, help the animals we all know and love.
April 22-30 is International Dark Sky Week hosted by the International Dark-Sky Association (IDA). The IDA’s main goal is to fight against light pollution, which is the inappropriate or excessive use of artificial light. Research from the IDA and other institutions indicates light pollution can have serious environmental consequences for wildlife, the climate and human health.
How does light pollution harm your favorite animals?
Some of the most devastating impacts of light pollution have been to animals and their habitats. For an example, look no further than sea turtles. Though this species lives in the ocean, sea turtles hatch at night on the beach, with hatchlings finding their way to the water by detecting the bright horizon over the ocean. Artificial lights have been known to confuse hatchlings and draw them away from the water and away from survival. In the U.S. alone, millions of sea turtles die this way each year.
Closer to home, light pollution can have a harmful effect on bird populations. Birds who hunt or migrate at night use light from the moon and stars to guide their way. Artificial lights cause these birds to wander off course and into cities, where they are met with dangerous terrain. Once attracted to illuminated areas, birds collide with the glass of needlessly lit buildings and towers. According to the IDA, millions of birds die this way each year. Additionally, migratory birds depend on cues from properly timed seasonal schedules. Light pollution can cause these birds to migrate too early or too late and miss ideal climate conditions for nesting, foraging and other behaviors.
Outside of these two species, the effect of light pollution on wildlife can be subtler but no less harmful. Nocturnal animals have had their nighttime environments radically altered by light pollution, taking away the darkness prey species use for protection and confusing animals such as frogs and toads, who use nighttime croaking as part of their breeding rituals.
Artificial lights have been shown to disrupt normal nocturnal behaviors, causing inference with breeding and decreasing animal populations, according to the IDA. The worst part? Researchers are only just beginning to understand the ways light pollution has harmed animals and their environments.
What is the Detroit Zoological Society (DZS) doing about light pollution?
DZS and Belle Isle Nature Center staff strongly believe in the importance of nurturing, celebrating and protecting the night sky everywhere. While Belle Isle will likely never be fully dark due to its proximity to the city, we do everything we can to preserve the island’s nighttime darkness and protect local wildlife.
The DZS is a partner with the Metro Detroit Nature Network, now known as SEMI Wild, which in 2017 signed the Urban Conservation Treaty for Migratory Birds, designating Metro Detroit an Urban Bird Treaty area. Among other things, the treaty promotes bird conservation through Lights Out programs. These programs, of which we are enthusiastic supporters, implement dark sky policies encouraging organizations and individuals to turn off or reduce interior and exterior lights during spring and fall migration to help provide safe passage to migratory birds — potentially saving the lives of thousands of our feathered friends in the Detroit area each year.
Another way we continue to protect dark skies is through community education and promoting programs that educate the public about the natural night sky and what the average person can do to fight light pollution.
This International Dark Sky Week, tune into the Detroit Zoo Facebook page to see multiple posts about dark skies, their connection to wildlife and how the DZS is celebrating the week.
You can also join us from 8:30 to 10:30 p.m. Saturday, May 7 for Statewide Astronomy Night. The Wayne State University Planetarium at the Belle Isle Nature Center will be hosting a free, outdoor-only event, where guests can observe the night sky through a variety of telescopes and binoculars. Wayne State presenters will also be on hand to offer tours of the constellations and conduct exciting demonstrations. The Nature Center will also host an installment of its Nature at Night series, where you can learn all about how local nocturnal animals navigate a nighttime world.
What can you do to fight light pollution?
While the problem of light pollution can seem insurmountable, every little action taken can make a big difference. Here are three things you can do at home and in your community to support naturally dark skies:
• Eliminate unnecessary indoor lighting. Unused lights — particularly in empty office buildings at night – should be turned off.
• Make the switch to shielded outdoor lighting. Outdoor lighting should be shielded and directed downward, where it can illuminate the ground rather than contaminate the night sky.
• Research and spread the word! Visit the IDA website to learn about light pollution and the organization’s efforts to preserve dark skies. Then become an advocate for them! Talk to your friends and family to raise awareness around light pollution and help them understand why they should make changes to protect the night sky.
If we all take steps to reduce light pollution in our own homes and neighborhoods, there is a chance that one day future generations — and their furriest friends — will be able to look up and lose count of the stars scattered across the dark night sky.
– Amy Greene is the nature centers director for the DZS.
It’s the season of sea otters at the Detroit Zoo! Over the coming weeks, Dr. Ann Duncan, director of animal health for the Detroit Zoological Society, will be sharing updates about two of the Zoo’s newest inhabitants, Ollie and Monte. Read on to learn more about some of our favorite marine mammals!
A year ago, Detroit Zoological Society (DSZ) animal care staff was busy renovating a habitat at the Arctic Ring of Life to become home for two rehabilitated sea otters, female Ollie and male Monte.
As the DZS had not cared for sea otters in the past, the veterinary staff was busy learning about the animals’ unique anatomical and physiological features and medical needs so we could provide the very best care. We reached out to veterinary colleagues experienced in sea otter medicine and were able to take part in online learning opportunities. We also gathered and read the literature describing typical sea otter medical problems and treatment.
Sea otters have several interesting adaptations, and caring for them is quite different from caring for similar animals, like North American river otters. Sea otters are in the water almost all the time, and when at the surface, they float on their backs. Unlike other marine mammals, sea otters don’t have fat under the skin for insulation. They instead rely on a unique hair coat and high metabolic rate. They have the thickest hair coat of any mammal — more than a million hairs per square inch! The hairs have tiny scales that interlock to form a dense, felt-like barrier that traps air and keeps the skin from becoming wet. This special coat is maintained by fastidious grooming, and when sea otters are not foraging or sleeping, you can usually observe them using their forepaws, flippers and tongues to care for their coat. Without a healthy coat, sea otters will lose heat to the water and cannot survive. When drawing blood, performing surgery or doing ultrasound, we avoid clipping any hair so that there won’t be a window for heat loss. Since the arrival of Monte and Ollie, we have regularly taken images of their hair coats using a thermal camera to look for any areas of irregular heat loss. So far, they have been perfect!
The metabolic rate of sea otters is eight times higher than the standard metabolic rate of similarly-sized terrestrial mammals, and they forage as often as every four hours and eat about 20 to 25 percent of their body weight in food each day. To meet these needs, we feed our sea otters at the zoo six times each day. Digestion of food generates heat and is an important strategy for maintaining body temperature while in cold ocean waters. We analyze the nutrient and energy contents of all the food items we feed to our sea otters and weigh them frequently to make sure they are meeting these high energy demands.
Sea otter skin is very loose, and they have two loose pouches of skin near their arm pits that they can use for storing and carrying food and other items.
Sea otters don’t have the best vision, but their eyes are uniquely adapted to allow them to see well both above and below water. Their ability to accommodate in this way is three times higher than reported in any other mammal. Sea otters close their ears and nostrils when diving. Their noses contain a complex labyrinth of turbinates that serves to increase the surface area for warming inhaled air as it enters the body and allows otters to have an excellent sense of smell.
Males are larger than females, weighing up to 100 pounds, compared to 75 pounds for females. Their lower incisor teeth are chisel shaped and protrude so they can be used to scrape food out of the shells of their prey. Their molars and premolars are wide and flat, perfectly shaped for crushing hard foods like clams and sea urchins.
My favorite sea otter adaptation is that they are cute! Sure, from a veterinary perspective, they are interesting, but they are also absolutely adorable. It’s impossible to watch them swim and interact without smiling, and it’s easy to want to do everything possible to help them thrive. All sea otters in human care have a medical condition that jeopardizes their ability to survive in the wild. I am proud of the Detroit Zoo for making a commitment to support the rescue and rehabilitation of stranded or injured sea otters by providing a long-term home for those who cannot be released. While we currently only care for Monte and Ollie, we have the space and resources to offer safe refuge for additional animals when needed in the future.
Stay tuned for my next blog, where I’ll describe a recent trip to the Monterey Bay Aquarium for sea otter medicine boot camp. There, I was trained firsthand how to restrain and perform anesthesia on these beautiful and unique animals.
– Dr. Ann Duncan is the director of animal health for the Detroit Zoological Society.