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How to collect a sperm sample from an elephant

Fertility rates of the majestic creatures are in mysterious decline, both in the wild and in captivity. If successful, Frozen Dumbo 3 will reverse that slide and change the way zoos acquire the animals.

A team of veterinarians, scientists, and volunteers attempt to turn a tranquilized 7-ton wild African elephant that had collapsed on his belly onto his side in preparation for an elaborate and messy procedure that will collect the animal's semen.MATJAZ KRIVIC


The Selati Game Reserve is located near the western rim of Kruger National Park. Encompassing more than 115 square miles — almost double the area of Washington, D.C. — Selati is a reserve without tourism, safaris, and human crowds. Upon entering, a visitor may feel that he has stepped into a densely lush, primeval paradise — an Arcadia on earth. But that would imply safety, and even here, despite patrolling park rangers, the resident elephants, rhinos, pangolins, and other animals fall prey to poachers.

Photographer Matjaž Krivic and I are in a Robinson Raven 44 helicopter with pilot Jana Meyer and veterinarian Hayden Cuthill. Hundreds of feet below is a herd of African elephants. Cuthill scans the lot for a healthy-looking male. For a long time, the accepted cliché was that the largest and strongest males must also be the most fertile. But both in zoos and in the wild, this has proved not to be the case. At the Selati, the highest sperm counts have been reliably found among males moving with herds with at least one female in heat.

A team on the ground follows the helicopter toward the spot where a tranquilized male elephant will have its semen extracted as part of Frozen Dumbo 3, a project that advances techniques for artificial insemination and sperm cryopreservation of African elephants.MATJAZ KRIVIC

This is Operation Frozen Dumbo 3, the goal of which is to better understand why wild African elephants’ fertility rates are in decline and to collect and store elephant sperm. A long-term goal of the operation is to bolster the elephant populations both in the wild and in captivity. One measure of success would be that zoos would no longer need to import the animals from the wild, which scientists now know wreaks havoc on their social structure and basic hierarchy, which are both crucial for healthy and regular breeding.

Spotting a good candidate below, Cuthill points it out to Meyer, who deftly maneuvers the helicopter to separate the chosen male from the herd. Cuthill, who is from South Africa and is a wildlife expert here, estimates the male’s weight and prepares the appropriate tranquilizer dosage. He attaches an ampule atop a special dart before making a direct shot into the great animal’s left flank. To miss, Cuthill knows, would be to risk the dart being eaten or trod upon by another animal — with potentially fatal consequences.

Hayden Cuthill takes aim with a tranquilizer dart at a male elephant below. MATJAZ KRIVIC

“We got a hit,” Cuthill reports to the convoy of four Jeeps on the ground. “Keep moving toward the chopper.”

The tranquilizer takes just three minutes to kick in, but they can be a long three minutes for the animal and for the team following from the sky and the ground, especially if other males in the herd follow the tranquilized one. Typically, if a female falls, the entire herd circles to protect her. On this day, the woozy male — viewed by the other males as competition — is left alone to stagger under the influence of the powerful drug.

‘The Sperminator’

A team of 20 or so veterinarians, scientists, reserve staff, and volunteers from around the world are on the ground. They are from Berlin’s Leibniz Institute for Zoo and Wildlife (Leibniz-IZW), Spain’s Bioparc Valencia Zoo, and the ZooParc de Beauval in France. There are also specialists from Wildlife Pharmaceuticals, a South African company that makes medicines used by zoo and wildlife veterinarians worldwide, and Israeli cryobiologists, here to dilute and freeze the collected elephant semen.

Meyer has guided both the helicopter and the elephant using some sharp maneuvers and loud sirens to a location deemed safest for both the bull and the humans who have come to perform the multistep procedure.

The creature’s collapse is slow and striking to observe. He looks to be made of jelly as he falls, and, once down, he resembles a beached whale. While still conscious, he issues a number of loud grunts and exhales blast after blast of hot air from his trunk. One of the volunteers keeps the tip of the trunk dilated with a wooden stick to ensure his breathing — elephants draw air exclusively through their trunks.

The team, with what looks like well-practiced moves, erects a metal contraption that stands nearly 10 feet high. They use it and a heavy rope to lift one of the elephant’s hind legs, the better to access the animal’s genitalia.

The elephant the team has dubbed "The Sperminator" is righted so that, upon waking from tranquilization, he will be able to get up. MATJAZ KRIVIC

On this, the fifth day of the Selati sperm-collecting expedition, some team members had been starting to worry. Most of the elephants sedated thus far either had insufficient stores of semen or their semen was too thin to be frozen in liquid nitrogen at minus-320 degrees Fahrenheit and stored in cryotanks.

Dr. Thomas Hildebrandt, the project’s head veterinarian and driving force, is one of the world’s leading authorities on rare breed and endangered species reproduction. He explains that, as with all Frozen Dumbo 3 sperm donors, this elephant bull will be subjected to a number of measurements — tail, tusks, penis, testes — which will be added to the scientific data archive. Veterinarians collect the bull’s blood and DNA samples. All the while, a Spanish-Lithuanian vet splashes cold water over the elephant and gently coos to him under the high, hot sun.

Hildebrandt, who has successfully artificially inseminated more than 50 female elephants, dons a green plastic gown and a pair of surgical gloves. Before he can perform an ultrasound and collect the elephant’s semen, there is the matter of an enema.

Hildebrandt inserts a pump into the elephant’s rectum and fills the intestines with an enormous quantity of water — to create space that makes an ultrasound exam possible. In an instant, a blast of elephant dung hits the German scientist almost full on. All in a day’s work. For the sleeping giant, the internal rinsing has a cooling and hydrating effect.

Hildebrandt, together with his long-time collaborator and close friend Frank Göritz, head veterinarian of the Leibniz-IZW, and Susanne Holtze, a scientist the department of reproduction management of the Leibniz-IZW, begins checking the sedated animal’s reproductive potential. Göritz measures the testes, prostate, urethra, and the ampullae, a trumpet-like organ in elephants that stores semen. Images from the ultrasound wand appear on a laptop screen and reveal good news.

The director of Bioparc Valencia (left) and the head veterinarian at Bioparc Zoo de Beauval hold the elephant's penis while Frank Göritz from the Leibniz Institute, right foreground, works to collect the animal's semen. MATJAZ KRIVIC

“Get ready! We’re about to start. This boy is loaded!” says the 60-year-old Hildebrandt, with apparent relief. The sedated male — we immediately dubbed him “The Sperminator” — was found to be near his full ampullary capacities.

Seven orgasms in 15 minutes

The scientists first extract and clean the elephant’s penis. Hildebrandt inserts an electric stimulation device into the animal’s rectum. The contraption looks like a miniature nuclear reactor and triggers sexual stimulation. It doesn’t take long. The bull convulses, and volunteers hold down his tail to limit the violence of his orgasms — on this day, we count seven in 15 minutes. The team collects the semen, which undergoes a dilution process and is stored in vials that will be relocated to a French cryobank.

“And we’re done!” exclaims Hildebrandt, who is drenched in the elephant’s urine, dung, and semen and his own sweat.

Cuthill injects the animal with the antidote to help him regain consciousness, and the rest of the team takes to mopping up. The meticulously sorted and labeled sperm samples are sent by chopper to the field lab almost 10 miles away.

Miri, a 6-month-old elephant born through artificial insemination using wild African sperm collected during Frozen Dumbo 3's predecessor project, Frozen Dumbo 2. She is healthy, playful, and mischievous and lives in BioParc Valencia, a Spanish zoo. MATJAZ KRIVIC

Word comes back not long after that the samples are good. Next, they will be frozen. Hildebrandt looks relieved.

The Sperminator first shakes his ears. Slowly, clumsily, he rises from his flank. It takes two tries. Once on all fours, he wiggles his trunk several times and stares at the distance for what feels like a long time. Then, as if kicked in the rump, he becomes alert and makes a few grunts. Nearly a quart of semen lighter, he races back into the bush.

Boštjan Videmšek is a journalist, a war correspondent, a playwright, and the author of six books. Matjaž Krivic is a documentary photographer who captures stories about social and environmental change.