An Un-bill-ievable Effort

Each morning in the Upland Tropical Rain Forest habitat begins with aviculturists using specific sound cues to summon the exhibit’s stunning array of colorful birds to appear for what is known as “the bug drop”—a daily routine that acts as both breakfast for rain forest birds and a headcount. That’s right! Our aviculturists know each resident bird by sight, carefully taking attendance as a rainbow array of tanagers, sunbitterns and others respond to their call, grab a bite and say good morning.

Among these birds is the blue-crowned motmot, a strikingly colored bird native to the rain forests of Central and South America. Motmots are notable for their distinctive plumage, with bright yellow, green and blue feathers on their back and tail, and a mask-like black band across their eyes. Also notable is the motmot’s unique housing preference; instead of building nests in trees, motmots use their strong beaks to excavate burrows in the ground where they shelter when laying and tending to their eggs. When they do perch in trees, they are known to swing their colorful tail feathers in in a pendulous fashion, and they are most vocal at dawn, calling with a soft, monotonous whoot whoot that many compare to the similar song of owls. Motmots are a fascinating species.

So, when the Aquarium’s resident blue-crowned motmot—known to our staff as Jack—appeared at the bug drop one morning this summer with an obvious injury to his upper bill but looking otherwise well, aviculturists noticed immediately. A large portion of Jack’s bill was missing but had been intact the night before, so aviculturists were confident that the injury was an accident sustained through normal activity. Motmots eat with their bills and sometimes kill their prey by hitting it on branches. Once his injury was detected, staff used his sound cue to ask Jack to move into a smaller enclosure so they could take a better look.

“Unfortunately, with a substantial piece of his bill missing, we knew right away that Jack would not be able to eat or preen his feathers independently,” recalls Deb Dial, assistant curator of the Upland Tropical Rain Forest and Australia: Wild Extremes exhibits.

While motmots’ bills do grow and repair over time, regrowth could be a long and uncertain process, leaving Jack dependent on staff for all of his basic functioning. Something had to be done, and the solution would unite National Aquarium experts from a variety of disciplines in attempting something they’d never done before.

After examining Jack, Deb and Director of Animal Health and Welfare Aimee Berliner reached out to Adam Nelson, the Aquarium’s habitat production lead, for some inventive solution sourcing. Typically responsible for the artful creation of everything from human-made corals in our reef habitats to realistic beachscapes in our newly updated Maryland: Mountains to the Sea exhibit, Adam and his team are experts in the creation of durable but scientifically accurate habitats throughout the Aquarium—but creating a bill prosthetic for Jack would be a first.

Using an oil-based clay, Adam worked with animal welfare staff to create a mold of Jack’s bill. This clay pattern recreated the missing section of the bill and was used to create a flexible mold out of a silicone rubber. The resulting mold was then used to create a negative copy of the clay pattern that the fabrication team filled with a more durable material to make the bill prosthetic.

“In this case we used a two-part epoxy resin with black pigment added for color matching,” said Adam. “Once cured, the epoxy prosthetic is safe, non-toxic and is both rigid and light, providing the performance characteristics needed for Jack’s bill to function as he needs it to.”

Once the bill was fabricated, it was up to Veterinary Fellow Kendra Baker to attach it securely. Using a safe epoxy material compatible with the lightweight plastic of the prosthetic piece, the process was a success.

“Attaching the beak is not as much difficult as it is delicate work,” according to Aimee. “It’s a small piece and is attached using glue so we needed to match it up as precisely as possible to give Jack the best opportunity for normal movement while grasping and swallowing. Once it was set in place, the prosthetic was shaped using a rotary tool to achieve the perfect fit.”

So, how is Jack doing? While he remains off exhibit, Jack is functioning just as he should. Since fitting his initial prosthetic in July, the team has already used the same mold and techniques to replace it once. While there is no way to anticipate how long each prosthetic will last, Jack's maxilla (upper bill) has grown 0.8 centimeters in a little less than two months. Sometime in the future, he will return to Upland Tropical Rain Forest sporting his fancy new prosthetic. Our goal is that his upper bill will continue to grow and eventually, when his prosthetic inevitably comes off, he will have enough bill growth underneath to allow for eating and preening without replacing it.

"Jack’s case was truly a cooperative effort between very talented and innovative National Aquarium teams,” said Deb. “The Animal Care and Welfare department's husbandry and animal health teams, along with the Aquarium's outstanding exhibits staff, were able to develop a plan and very quickly return Jack to his natural state. We are monitoring him constantly and expect him to continue to do well. We are looking forward to his return to Upland Tropical Rain Forest in the not-so-distant future!"