That shiny reflection beaming off Vus’Musi’s tusks at Fresno Chaffee Zoo may look like bling, but it has a purpose.
Fresno Chaffee Zoo’s male African elephant has a reputation for cracking or breaking tusks. He did it at his previous home at San Diego Zoo Safari Park, and it has happened at Chaffee Zoo, too. Until now.
In a year of frustrating endeavors to keep Vus’Musi from further tusk torment, zoo officials seized on a solution of special caps. It’s been more than six months and, so far, so good.
“He had a history of being tough on his tusks, and he would break them on things,” said Vernon Presley, Fresno Chaffee Zoo curator for African elephants and ungulates (mammals with hoofs).
He said keepers had to clean out areas where Vus’Musi had broken or cracked his tusks weekly, or more often.
“He was damaging the ends of his tusks, and we wanted to make sure he didn’t break them off,” Presley said.
Elephants use tusks to dig, lift or rub against trees, causing damage to what are essentially external teeth that extend into the upper jawline.
He had a history of being tough on his tusks, and he would break them on things.
Vernon Presley, Fresno Chaffee Zoo elephant curator
Breaks and cracks in tusks can lead to infections, potentially causing serious illness. It’s comparable to a human breaking a front tooth and exposing nerves, Presley said.
“It’s as if someone grabbed your tooth and yanked it out; you would worry about an infection that could go up into your skull and other parts of the body,” Presley said.
In San Diego, keepers used a type of medical resin called Technovit to protect Vus’Musi’s tusk. But Chaffee wanted a better method.
“We wanted more of a permanent solution,” Presley said. “We had to replace the Technovit once a week or more than once a week, but we wanted something a little more durable.”
Vus’Musi’s capped tusks often prompt visitors’ questions, said Shane Spears, an elephant zookeeper.
“We can explain why the caps are important to their care,” Spears said. “It gives us a way to discuss training and expose people to the breadth of elephant care.”
Breaking the mold
After speaking to fellow elephant keepers in Indianapolis, Presley supported the idea of covering the tusk with metal. The plan was to make a plaster of Paris mold and then find a foundry to create a stronger material for the outer tusk.
He did a Google search and found Fresno Valves and Castings, a Selma-area foundry and irrigation line fitter, and spoke with Sergio Hernandez, the pattern shop supervisor.
The company forged a brass tusk cap from the plaster of Paris mold that acts like a crown for human teeth.
“I told him we had an unusual request,” Presley said, referring to his initial call last July. “But Sergio said he could help us out.”
Fresno Valves was recently asked to make a brass engine block for a custom 1939 Harley Davidson motorcycle. So, while an elephant tusk protector was unusual, Hernandez said he was unfazed.
“After Vernon described it to me, I said we could try it,” he said. “It was a challenge, and we like challenges … but we never made something like this before.”
It took two days to pattern and a third day to pour the brass, Hernandez said. The first attempt, using a soft brass, was unsuccessful, and Vus’Musi broke it.
It was a challenge, and we like challenges … but we never made something like this before.
Sergio Hernandez, Fresno Valves and Castings
Hernandez’s crew started again, this time using a harder brass. It worked.
Despite all the staff time and materials, Fresno Valves did the work for free, Presley said.
Zoo veterinarians applied adhesive to Vus’Musi’s tusk, put the brass cap on and placed “set screws” in tiny holes to ensure the cap stayed attached until the adhesive cured.
The first one has held since August. In October, Presley called Hernandez again because Vus’Musi damaged his other tusk and needed a matching shiny front incisor.
This time the process was simpler, and Vus’Musi was fitted fairly quickly. Vus’Musi popped it off twice during pachyderm play. The third time, the brass tusk was set and it’s been in place since, Presley said.
As an elephant ages, the pulp cavity, where the nerves run and infection can spread, will no longer be a center for infection. But while he’s still young, about 13 years old, Vus’Musi has to break his tusk-busting habits, Presley said.
“We’re hoping for a permanent solution until that (pulp cavity) grows out,” he said. Until then “we have the cap to protect chipping and cracking, holding the tusk in place for us.”
Other zoos have attempted different solutions, using adhesive to fill the cracks or wrapping a tusk for protection.
Indianapolis has elephants and walruses fitted with tusk caps similar to Fresno’s.
The Indianapolis Zoo has been using metallic tusk protection for 20 years after getting help from a nearby dental school. Zoo officials say the metal caps last, on average, about a year, but some have lasted four to six years.
After Vus’Musi’s mischief, Presley said, Fresno zoo officials called Indianapolis and inquired about the brass fitting’s durability. Indianapolis officials suggested seeking a local foundry, a fortunate turn of events for both zoos.
After an elephant in Indianapolis broke his tusk cap last month, Presley got a call asking for his help because Indianapolis Zoo officials were told their foundry had a 45-day wait and infection was an immediate concern.
Hernandez told Presley the business could help. The plaster mold was sent overnight from Indianapolis and was made in a few days at Fresno Valves, then shipped back.
Fresno Valves offered the service free but Indianapolis Zoo officials insisted on paying.
Dr. Jeff Proudfoot, a veterinarian at the Indianapolis Zoo, said it cost about $375, a bargain considering the price of brass. Zoo officials wanted to pay in case they would require the company’s services again, he said.
“The crown was beautiful and fit nicely,” he said.
There are so few of these animals in zoos that we have to try new things that have never been done before and learn from each other.
Elizabeth Stringer, Denver Zoo veterinarian
In 2015, a male elephant at Birmingham Zoo developed an infection that the veterinary staff was unable to treat effectively. The University of Alabama-Birmingham developed a resin used in building airplanes and wrapped it around his tusk.
“It stood up well to to rubbing his tusk on things,” said Kiki Nolen-Schmidt, the zoo’s marketing coordinator.
But months later, zoo officials noticed the crack in his tusk expanding and decided the best approach was to cut the tusk back.
“They have been able to manage the infections, and they did prevent the crack from growing,” Nolen-Schmidt said.
Denver Zoo worked with an aerospace engineering firm that uses Kevlar and fiberglass. They had “mixed opinions” about metal caps and wanted something that looked more authentic, said Elizabeth Stringer, a zoo veterinarian.
The material was selected because of its resistance to impact and shearing forces from digging and playing. The tusk cap lasted about a year, she said, before requiring replacement.
A left tusk cap lasted between six and seven months before falling victim to elephant exuberance, but it was reinforced and has stayed on 15 months since. The second cap was installed 15 months ago and “is still on and still looks good,” Stringer said.
“We need to try different approaches,” she said. “There are so few of these animals in zoos that we have to try new things that have never been done before and learn from each other.”