Throughout spring migration, the Detroit Zoo’s 125 acres provided refuge to many weary travelers. Now that the season is coming to a close, our staff is looking back at all the feathered friends who used our grounds as a stop on their journeys.
Over the last couple months, Detroit Zoological Society (DZS) team members have spent many hours surveying what bird species have been utilizing the habitats here at the Detroit Zoo. Some of these species live here year-round, while many species have shown up during migration and will spend the summer here breeding on Zoo grounds. Additionally, several species have used the Zoo to rest or refuel for a matter of hours or days on a long journey home to their breeding grounds.
We have seen and heard many species of songbirds, black-crowned night herons, a redhead, spotted sandpipers and much more! From March until the end of May, we accumulated at least 93 species on Zoo grounds.
The incredible journeys these brave travelers make every year are hard to put into words. Many winter as far south as Central or South America and may head far north of us into the Upper Peninsula or northern Canada to breed. The blackpoll warbler is one of these extraordinary migrants who recharged at the Zoo this May. This tiny, insectivorous species only weighs around 11 grams and sings a very high-pitched song. They often travel more than 10,000 miles round trip — including an Atlantic Ocean crossing — as they head back and forth from South America to northern Canada and Alaska.
Migrating birds overcome extreme challenges when heading back and forth between breeding and wintering grounds. Besides exhaustion and native predators, there are many human-made challenges. Fragmented habitats, light pollution, domestic cats and windows are just some of the man-made threats that make migration even harder. Here at the Detroit Zoo, we are proud to provide these birds an excellent, protected habitat on their perilous journeys.
It’s the most wonderful time of the year. No, not Christmas — bird migration season! It’s the time of year when birds who left Michigan during the winter months to find refuge in warmer states make their triumphant return. Look outside, and you are likely to see robins, Canada geese and sandhill cranes among the birds flying in the spring Michigan skies, happy to be back after a cold winter away.
While everyone at the Detroit Zoological Society (DZS) celebrates these birds every day, we are encouraging the public to join us in celebrating and raising awareness around the conservation of local species on World Migratory Bird Day (WMBD) May 14.
WMBD, formerly International Migratory Bird Day, is an annual campaign highlighting the need for the conservation of migratory birds and their habitats. Through a collaboration of festivals and events from partners across the globe, WMBD brings awareness to the threats migratory birds face, as well as the birds’ ecological importance and the need for bird conservation.
While all aspects of bird conservation are important, this year the organizations behind WMBD are focusing on fighting light pollution and harm it can cause to migratory birds.
Light pollution, or the inappropriate or excessive use of artificial light, affects our world in numerous ways, from limiting our view of the night sky to disrupting human sleep patterns. However, light pollution’s most devastating impacts are felt by wildlife — and migratory birds are no exception.
Most birds migrate at night due to the calm skies and lack of predators. These birds use the moon and stars to guide their way — a system that has worked for eons. However, with light pollution encroaching further and further along the night sky (at a rate of increase of at least 2 percent per year, according to the Smithsonian Migratory Bird Institute), migratory birds’ journeys are becoming increasingly dangerous. Read our recent blog post to learn more about light pollution and how to mitigate its effects on local wildlife.
When artificial lights from nearby cities enter the night sky, migrating birds can become distracted and veer off course into threatening territory. When distracted by light pollution, birds become more likely to land in dangerous areas, where they are prone to collisions and vulnerable to unfamiliar predators.
One of the biggest dangers presented to birds drawn into urban areas impacted by light pollution is needlessly illuminated office buildings. According to the International Dark Sky Association, millions of birds in the United States die each year by colliding with empty office buildings and towers that are lit up at night. Additionally, light pollution impacts migration patterns, confusing and disrupting mating and feeding schedules.
Canada geese returning to summer in Michigan.
All of this information paints a bleak portrait for the future of the feathered fowl who migrate across the U.S., but don’t lose hope! There are things each and every one of us can do to help local birds travel safely.
• First, turn off your lights at night. Unused lights, particular in unused office buildings, present a great danger to traveling fowl.
• Second, 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.
• Third, research and follow bird-safe habits that help reduce the hazards birds face during the migration process. In addition to turning lights off at night, these practices can include installing screens, decorative window film or window art to help prevent birds from hitting glass; moving feeders as close to windows as possible and bleaching bird feeders once a month; and practicing green gardening by growing native plants and avoiding insecticides.
The DZS has long been a supporter and practitioner of bird-safe initiatives. In 2017, we made it official by partnering with the Metro Detroit Nature Network, now known as SEMI Wild, which 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. Now, five years later, we are proud to promote these Lights Out programs, which encourage organizations and individuals to turn off or reduce interior and exterior lights during spring and fall migration, in honor of WMBD.
While there is much to be done to provide our feathered friends with safe travels this migration season, know that you can play a part by turning off one light at a time.
–Bonnie Van Dam is the curator of birds for the Detroit Zoological Society.
In March 2020, my suitcases were packed, and a group of 40 volunteers was ready to fly down to Iquitos, Peru to deliver school supplies to remote communities along the Amazon and Napo rivers in the heart of the Amazon Rainforest.
Three days before my flight, Peru closed its borders in an attempt to slow the spread of COVID-19. The Peruvian school year starts in March, so schools didn’t open for months, and even then classes were hosted only virtually. This provided an opportunity for many of the students who lived in cities to attend but left behind the communities on the river, which had no devices or access to the internet. For two full years, Adopt-a-School community partners had no access to formal education. Even more devastating than the education gap, Peru holds the highest rate of COVID-19 fatalities out of any country in the world.
This year, as I packed my bags again, I couldn’t help but wonder if we would be able to travel. With new variants being identified regularly, I was very conscious of the responsibility that comes with international travel. I needed to keep myself and the communities we would be visiting healthy, as well as my family when I returned home. I took extra precautions, including wearing an N95 mask the entire time I was traveling through airports and on planes. As health care workers know all too well, wearing an N95 mask for 24 hours straight is challenging and not comfortable!
When I arrived in Iquitos, I met with our partners at Conservación de la Naturaleza Amazónica del Peru AC (known as CONAPAC), the Peruvian nonprofit that facilitates the Adopt-a-School program and several other important projects in the rainforest. A small group of volunteers that had been scheduled for the 2020 trip joined us for the school supply deliveries. We reviewed our ambitious schedule of visiting nine schools each day for five straight days and packed all the school supplies onboard the cargo boat that would be traveling with us on the river.
The process of traveling to communities and sharing school supplies repeated throughout the week. Toward the end of their school year (likely in September), we will reach out to all the teachers in the communities to ask what supplies they need for their classroom. That way, we can tailor the 2023 delivery to their needs. All the materials are purchased in Peru, which supports the local economy, ensures materials fit with local curriculum guidelines and drastically reduces shipping and customs fees. The supplies are purchased with donations from an international group of donors, many of whom have traveled to the rainforest previously. If you would like to support the Adopt-a-School program, ensuring access to educational opportunities in the heart of the Amazon Rainforest, please visit our website for more information.
– Claire Lannoye-Hall is the director of education for the Detroit Zoological Society.
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.
The Detroit River in the winter can be an inhospitable place. The temperatures dip into the teens, and the wind whips large plumes of snow from the tips of frozen waves. This large and fairly fast-moving river flows south and southwest, connecting Lake St. Clair and Lake Erie. The river plays an important role as a shipping channel for freighters carrying industrial compounds and other materials used for manufacturing.
Underneath all of this ice and hustle and bustle, one of the river’s most curious and secretive animals is carrying about its business, breathing with large, bushy external gills, foraging along the rocky bottom for food and undergoing mysterious mating behaviors. This animal is known as the northern mudpuppy (necturus maculosus maculosus), and the frozen and harsh conditions of the Detroit River are just what it’s been waiting for all summer long.
Mudpuppies are amphibians who inhabit lakes, streams and rivers all throughout the U.S. Midwest and into parts of Canada. It is a type of fully-aquatic salamander that utilizes external gills, which are flush with blood and used to extract oxygen from its aquatic environment. Its tail is large and paddle like, and its skin is covered in a thick layer of slime. These salamanders, like all amphibians, have permeable skin and are considered to be a good indicator of environmental quality. This is one of the reasons the Detroit Zoological Society (DZS) began tracking the health and abundance of mudpuppies back in 2009.
In 2016, the Michigan Department of Natural Resources elevated the conservation status of the northern mudpuppy to a species of special concern. Since that time, the project has continued and expanded, focusing primarily on Belle Isle Park in the city of Detroit. The Detroit Zoo utilizes minnow traps to capture the mudpuppies without harming them while still collecting important data. The traps are baited with smelt and catfish bait to lure these aquatic salamanders into the minnow traps. The traps are set on the first day of the survey and pulled in on day two, so that the animals spend the least amount of time possible inside. If a mudpuppy is found inside, DZS staff proceeds to gather data and observations about the animal, including size, weight and gender. The gills are checked for health and examined for parasites. The digits on all the limbs are checked for malformations, which could indicate the potential presence of pollutants in the river.
Once these measurements are taken, the animal is tagged with a Passive Integrated Transponder tag, which is injected into the base of the tail. This transponder can be scanned if the animal is captured again. Additionally, it tells DZS researchers useful information that can be used for future data analysis. In addition to these measurements, data is collected on water quality and additional environmental conditions, such as temperature and dissolved oxygen content.
Based off the data so far, most mudpuppies are caught in late fall or early winter. During this time, male mudpuppies are pursuing females in the quickly cooling shallow water close to the island. Many times, staff has observed male and female mudpuppies in the same trap this time of year, most likely with the female entering the trap first before the eager male mudpuppy follows her inside. Once mudpuppies have successfully bred, the females deposit their eggs in spring, and within a month or two, the eggs hatch into several hundred baby mudpuppies!
All of this drama is taking place out on the frozen Detroit River. With ice floats and enormous boats hovering overhead, these specialized amphibians continue to live and breed intertwined in an urban environmental landscape that still holds many secrets yet to be revealed.
– Mark Vassallo is an amphibian department supervisor for the Detroit Zoological Society.
This month, the Detroit Zoological Society is bringing you not one, but three blog posts centered around our favorite flippered friends — the penguins who live at the Polk Penguin Conservation Center (read the first and second entry). The facility, which had been closed since 2019 due to waterproofing issues, reopened in February, and we can’t wait to share with you all the stories we have been saving over the past two and a half years.
In our final March of the Penguins entry, learn how animal care staff ensured the flock was thriving while its home was being repaired.
It has been a while since the public has been able to visit the penguins who call the Detroit Zoo home. You might have been wondering – what were the penguins doing during that time? In order to answer that question, staff and dedicated volunteers from the Center for Zoo and Aquarium Animal Welfare and Ethics (CZAAWE) spent nearly every day monitoring the penguins for the last two and half years.
While repairs were being made to the Polk Penguin Conservation Center (PPCC), the penguins returned to their previous habitat, the Penguinarium. Animal care staff went above and beyond to make their extended stay in the Penguinarium more comfortable, including bringing snow into the habitat and even letting the penguins walk around Zoo grounds. The penguins’ move provided us with an interesting opportunity to monitor their transition between habitats and compare how they used their previous space compared to their new home in the PPCC.
The PPCC was designed to give the penguins more opportunities to express natural behaviors. It contains a 326,000-gallon pool, which holds 10 times more water than their previous habitat and is equipped with an adjustable wave machine for the penguins to enjoy. Additional improvements were made while the building was closed for repairs, including adding second snow machine within the habitat, more nesting areas and enhanced lighting.
One of the important roles CZAAWE plays at the Detroit Zoo is monitoring how major habitat modifications impact an animal’s welfare. The Association of Zoos and Aquariums defines animal welfare as an animal’s physical, mental and emotional state over a period of time, which is measured on a continuum from good to poor. Since we can’t ask the penguins what they think about all of the new features, we have to rely on decoding their behavior. CZAAWE staff and volunteers have conducted more than 5,000 observations in order to understand how the new habitat impacts the penguins’ welfare. During every observation, CZAAWE staff and volunteers record several indicators of welfare, including the penguins’ behavior, their location within the habitat and the features of the habitat they are using. Our hope was to see the penguins use a variety of different features and locations within the habitat in addition to engaging in the same natural behaviors as their wild counterparts.
We found preliminary results varied between each species. For example, the 25-foot-deep pool in the PPCC was successful in promoting swimming in king penguins, who swam more than 10 times more in the PPCC than in their previous habitat. The macaronis, rockhoppers and gentoos relished their new nesting sites, spending more time engaging in nest building behavior than they did in the Penguinarium. The gentoo penguins began to utilize the elevated nesting sites, a feature they did not use in their previous habitat. Additionally, the chinstraps had the opportunity to discover one of their favorite features of the new habitat – the underwater bubbles! Although we saw many positive signs from the penguins in their new home, CZAAWE’s monitoring revealed that the penguins continued to thrive during their stay in the Penguinarium. They maintained their use of the pool and engaged in a healthy variety of behaviors, which is often considered a positive indicator of welfare.
Our research also revealed some patterns regarding the location of each species within their new habitat. The PPCC is split into two sides to emulate the natural habitats of all five species that live at the Detroit Zoo. The southern rockhopper and macaroni penguins, typically found on rocky sub-Antarctic islands, are most likely to be found on the South American side of the habitat when you first walk into the building. The king penguins can be found near the snow piles on the Antarctica side of the habitat, while the gentoos tend to use all parts of the habitat. Our newest residents, the chinstrap penguins, are most likely to be found in the water. Most of the species gravitate toward areas of the habitat that are most similar to their natural habitats!With a new habitat comes new opportunities for both penguins and Detroit Zoo guests! What was once a rare opportunity to see king penguins immersed in the water is now a normal sight at the Penguin Center, and the large viewing windows now make it possible to get nose-to-beak with some of your favorite birds. We are thrilled to welcome you back to enjoy some of the positive benefits that major habitat modifications have had on the penguins at the Detroit Zoo.
– Megan Jones is a research associate for the Center for Zoo and Aquarium Animal Welfare and Ethics.
This month, the Detroit Zoological Society is bringing you not one, but three blog posts centered around our favorite flippered friends — the penguins who live at the Polk Penguin Conservation Center. (read the first blog post, here) The facility, which had been closed since 2019 due to waterproofing issues, reopened in February, and we can’t wait to share with you all the stories we have been saving over the past two and a half years.
Next in our March of the Penguins series, learn how animal care staff saved the life of a hatching macaroni penguin.
We’ve all heard stories from friends and family of difficult birthing events, sometimes resulting from a baby that is positioned incorrectly in the birth canal, often called a breech delivery. You may not realize that something similar can happen during the hatching of a bird.
Fertilized eggs contain all of the nutrients needed to support a chick during development. As the chick grows, an air pocket forms at one end of the egg. For a chick to survive, it must be positioned so that it can push its beak into this air pocket just before it’s time to begin hatching. Some developing chicks are rotated or positioned incorrectly so that they can’t reach this air pocket – this means that the chick can only survive if given assistance. Over the years, bird and veterinary staffs have worked together to assist the hatching of several developing eggs.
The bird staff monitors eggs under development very meticulously. They take daily weights to ensure eggs steadily lose weight, a sign that the air pocket, (otherwise known as an air cell) is growing larger. The staff also shines a special bright light through the eggs, a procedure called candling. Candling allows you to see an outline of the developing chick and air cell. Once incubation nears the end, radiographs can also be taken to visualize the skeleton of the chick and ensure the embryo is positioned normally.
In 2021, the Detroit Zoo had a single fertile macaroni penguin egg. On day 37 of a 37-day incubation period, radiographs were taken to see if the chick was able to hatch normally. The radiographs showed the chick was malpositioned in a way that can be fatal — the chick was rotated, and the beak would not be able to reach the air cell. We could feel the chick moving, and it seemed strong. After discussing our findings, we decided to begin the process of assisting the chick to hatch.
The shell was cleaned gently, and a Dremel tool was used to make a small opening. A sterile tool was then used to gradually make the opening larger until the position of the chick’s beak could be confirmed. We then made a very small hole in the membrane overlying the chick’s beak. This allowed the chick to begin breathing air, so that it can stay strong and continue hatching. Chick embryos develop with the yolk sac outside of their abdomen, and as they near hatching, the yolk sac is gradually enveloped inside of the belly to provide nutrients for the first few days. Through the opening in the shell, we could see that the chick needed more time to absorb the yolk sac. We set the chick up in a warm, humid environment, and checked on it frequently. We also began offering one or two drops of water every few hours.
The next morning, we were very happy to see that the yolk sac had been mostly absorbed. We removed more of the shell to expose the belly, cleaned the skin over the belly and placed a suture to hold things in place. We then gently coaxed the chick out of the shell. In all, the hatching process took about 24 hours, which mimics the timeline of normal hatching. The macaroni chick is doing well, and is currently learning to swim in the Polk Penguin Conservation Center. She was named Betty and as you can see is full of character. We are very happy to have been given the opportunity to get her started on a long, healthy life.
– Dr. Ann Duncan is the director of animal health for the Detroit Zoological Society.
This month, the Detroit Zoological Society is bringing you not one, but three blog posts centered around our favorite flippered friends — the penguins who live at the Polk Penguin Conservation Center. The facility, which had been closed since 2019 due to waterproofing issues, reopened in February, and we can’t wait to share with you all the stories we have been saving over the past two and a half years.
The Detroit Zoo was very eager to welcome a king penguin chick who hatched in 2020. Even though we have raised many penguin chicks throughout the years, we haven’t raised a king penguin chick in 19 years, so this was truly a “king-sized bundle of joy!”
The rearing of this chick is also an interesting story. During courtship, king penguin pairs form a tight bond, which culminates with the laying of a single egg. Unexpectedly, this was not the case for the parents of this chick. Once the egg was laid, the pair was moved into the rookery with the egg. The rookery is an area within the penguin habitat that provides some separation and privacy while the pair incubates their egg and raises their chick. The female was immediately receptive to the male, lifting her brood patch and showing the male their precious egg. The male appeared receptive initially, but rather than soliciting the egg transfer, he quickly became aggressive towards the female.
Normally, the female will transfer the egg to the male shortly after it is laid, usually within 24 hours. Both will share incubation duties, with the male completing the larger share. We decided to give the male a fake egg for a couple of days, while the female incubated the real egg. After several days, he proved to be a good egg incubator but was still aggressive towards the female. Once the egg was determined to be fertile, we gave it to the male but knew that we had to develop an alternate plan for rearing this chick.
Fortunately, another pair whose egg was not fertile met the criteria for becoming foster parents. Egg fostering is a technique we have used in the past with other penguin species, either to give another pair the opportunity to rear a chick or when a pair is not able to rear a chick. The foster male (and the biological male) are actually the last of three king chicks to be reared here 19 years ago. Although the foster male had never raised a chick before, the foster female had raised a couple of chicks previously. In fact, she raised the biological “father” 19 years ago, and therefore is the “grandmother” of this chick! We initially gave the foster pair a fake egg, and about halfway through the incubation period, we transferred the real egg from the biological male to the foster male.
The average incubation period for king penguin eggs is 54 days. On day 54, we noticed an empty eggshell on the ground near the parents – the chick had hatched! Since then, the male chick has fully grown and was given the name Archie. We love seeing this “royal” bird in the habitat and remembering the special foster story that made it possible.
Come visit Archie and watch this fabulous flock waddle, dive, swim and display other natural behaviors in the Polk Penguin Conservation Center.
Bonnie Van Dam is the curator of birds for the Detroit Zoological Society.