The following is a re-formatted version of the Cover
Story article "Sex and the Single Rhinoceros," which appeared
in the Feb. 20, 1998 edition of the Chicago Reader newspaper.
The text has been reformatted, and some of the photos
have been changed.
No one's watching the animals on a late December afternoon at the
Milwaukee County Zoo, though the weather's mild. Several beasts are
taking the air, but all the keepers are inside. You can see them through
the Plexiglas window in front of the rhinoceros cages - a knot of
five people in boots and sweaters grouped around a lean woman in a
drab blue jumpsuit, Dr. Nan Schaffer, a Chicago-based exotic-animal
veterinarian and researcher who's here to demonstrate a little of
what she knows about rhino reproduction.
In the cage behind them a two-year-old black rhino named Pombe
is trying to get their attention. He pushes a tree stump with his
snout. He trots to the back of his cage, spins, and then hurtles
straight toward the bars. About halfway there he suddenly brakes
and leaps straight into the air, all four feet off the ground at
once - a vertical leap of about three inches. He hits the floor
sliding and slams against the bars. "OK," Schaffer says,
laughing. "We see you."
Schaffer is one veterinarian who makes cage calls. She does consulting
work on all kinds of exotic animals - from lions to camels to gorillas
- at zoos and sanctuaries all over the world, and she's a regular
at the Sedgwick County Zoo in Wichita, Kansas, as well as at the
Milwaukee Zoo. She has also been on call at the Lincoln Park Zoo
and the Brookfield Zoo as a veterinarian.
Schaffer's specialty is the physiology of rhinoceros reproduction,
and no one in the world knows more about it than she does. She's
written or cowritten close to 100 professional articles on the subject.
She's given numerous presentations, ranging from "Overview
of Procedures and Results of Semen Collection From Ambulatory Rhinoceroses"
(at the Milwaukee Zoo in 1988) to "Gross Anatomy of Reproductive
Structures and Their Ultrasonographic Images in the Rhinoceros"
(at the first International Symposium on Physiology and Ethology
of Wild and Zoo Animals, in Berlin in 1996). Her fieldwork has been
groundbreaking, the results she's achieved unique. Yet outside her
field she's unknown. She's never been on Animal Planet or the Discover
Channel or a National Geographic special. She hasn't even been on
It's not that these shows shy away from animal reproduction -
quite the contrary. But Schaffer's research requires her to get
up close to male and female rhinos in a way that makes some people
uncomfortable. There's more than one way, for instance, to go about
collecting semen from a rhino, but the simplest and most practical
is the most direct: the semen is coaxed out of him by hand. And
that's something even zookeepers would really rather not talk about.
But then Schaffer preferred to remain unknown until two years
ago, when she started SOS Rhino, a nonprofit organization funded
through the rhinoceros reproduction program of the Milwaukee County
Zoo that promotes research on all five species of rhinoceros and
publicized their plight. An SOS Rhino Web site appeared last year,
complete with animated pictures of rhinos in the wilderness. The
slogan on the site read "Inform + Entertain = Empower."
The rhinos' situation is desperate. All five species - black,
white, Indian (or Nepalese), Sumatran, and Javan - are on the world's
endangered species list. The estimated total living in the world
is 11,370 with 6,500 white rhinos, 2,500 black, 1,900 Indian, 400
Sumatran, and 70 Javan. Schaffer has a particular affection for
the Sumatran rhinos, which haven't adapted well to captivity, and
wishes more people could see them before they disappear. She describes
them as loners that live in the jungles of Malaysia and tend to
shy away from people and each other. "They're small, woolly,
personable," she says. " They talk in squeaky voices."
The rhinoceros is an "umbrellas species," meaning that
it if can survive in the world, many other species can survive too.
"It's pretty high up on the totem pole, on the pyramid of animals,
because it is such a large species," says Schaffer. "If
you save a species like that in its habitat, then you're saving
a sizable area. You've got rhinos in savanas, you've got rhinos
in jungle situations."
Much of the rhino's traditional habitat has been broken up by
development. "When they start dividing up these areas - you
have a little sanctuary here and a little sanctuary here and one
over here, and you have all these people in between - the rhinos
can't get to each other. That's a fragmented ecosystem." And
transporting animals from one of these areas to another so they
can breed isn't easy or cheap.
Rhino populations are declining everywhere but South Africa, which
has aggressively protected its white rhinos. The illegal trade in
powdered rhino horn in Asia has been a catastrophe. Rhino horn,
crushed and bottled, is a folk remedy for a variety of ailments,
though it's used mainly for impotence. Demand has a lot to do with
its price and in China one horn can sell for several thousand dollars.
Studies show the powdered horn has no effect - which isn't surprising,
given that it's made up of keratin (the same thing that makes up
human fingernails) and compacted hair.
But the trade is entrenched, and the method of gathering horns
is gruesome. "The poachers have to work fast," Schaffer
says. "If they don't they get caught. So what they do is shoot
the rhino with an AK-47, then cut off his nose with a chain saw."
She says the poachers are often in such a hurry they don't bother
to see if the animal is still alive before unleashing the chain
Hoping to help save the species, zoos set up captive breeding
programs. But they've had problems. For one thing, transporting
rhinos of any species of either sex from one zoo to another is at
least as difficult as transporting them in the wild. For another,
rhinos can be choosy when it comes to selecting a mate. And the
breeding process itself is a titanic battle of the sexes that can
lead to injuries, especially in a confined area. Moreover, the females
often don't get pregnant.
And even when captive rhinos do get pregnant they're more prone
to complications than wild rhinos. In 1992 Schaffer went to Wichita
to manage the pregnancy of an older rhinoceros named Bibi, a 31-year-old
black rhino who'd had several spontaneous abortions (rhinos in their
mid-30s are considered old). Bibi had given birth to two calves
in her teens, but she hadn't delivered in 15 years. She'd been on
loan from the Detroit Zoo since 1988 and had been bred regularly
to the same male. She got pregnant three times but aborted each
time. Pregnancy in a rhino usually lasts between 14 and 16 months;
Bibi's most recent pregnancy, in 1991, was over within 4. The zoo
separated her from the male for a few months, and as soon as she
was put back together with him she was pregnant again. Worried that
she would abort again, the zookeepers called Schaffer.
The zoo put Bibi in a restraint chute so Schaffer could do an
ultrasound, but the ultrasound didn't show anything. Bibi seemed
in fine general health, though she did have a couple of problems.
"Her teeth were bad, so they started chopped up her food. And
it was hard to keep her vaginal infections under control."
Schaffer paid regular calls to Bibi's pen and devised treatments
for each new problem that came up. Bibi became anorexic and depressed
for a short period, but after being treated for an abscess on her
toe she regained her appetite and pleasant demeanor. She also had
occasional skin ulcerations, which were treated successfully with
ointment. "We started supplementing her with progesterone,"
says Schaffer. She was also given molasses twice a day to raise
her glucose levels.
"Through all this management she finally was able to maintain
her pregnancy," Schaffer says proudly. "There's at least
one more rhino in the world because of me." On August 16, 1993,
Bibi delivered a healthy male calf. She was the oldest black rhino
to give birth in captivity.
Though Bibi had gone a long time since having a calf, she was
still a mother. "She actually became a little terror,"
Schaffer recalls. "She wouldn't let anybody in the barn or
anywhere near this offspring. It took about a month for them to
finally be able to get in there."
Given all the difficulties of breeding captive rhinos, and worried
that time was running out - every time a rhino dies or is killed,
one more unique set of genes is gone forever - Schaffer in 1981
began researching the potential for artificial insemination. But
what seemed simple turned out to be not so simple after all.
One big problem lay with the mechanics of the insemination process.
Fully erect, a rhino's penis extends up to two and a half feet and
is shaped like a lightning bolt. To accommodate it, the reproductive
tract of the female rhino is also quite long, with many twists and
angles of its own that make it hard to get an inseminating probe
in to the uterus. Schaffer studied the reproductive organs of dead
females, trying to devise a probe that could negotiate the curving
tract. She tested several different models, but each one was stopped
by the lotuslike folds of tissue that make up the cervix.
Schaffer might have thrown up her hands and admitted that nothing
but a male rhino could impregnate a female rhino, but she now believes
she's close to a solution - though after a dozen years of trying,
she's worried that she still might not get past the cervix.
Schaffer grew up on a dairy farm in Texas. Her father was a pathologist,
her mother a horse trainer who managed the farm. Schaffer went to
Texas A&M intending to become a veterinary biologist working
on domesticated animals. But she soon realized, "With the vet-tech
degree, I would have been overqualified for most the jobs that were
out there." In her sophomore year she took a trip to east Africa,
and she soon knew she wanted to go back. One route was to focus
on exotic animals.
In her last year at school Schaffer was working with male gorillas,
many of which were having a hard time breeding in captivity. They
simply didn't know what to do with the females, she says. "They'd
been raised alone and couldn't adjust to a female in the cage. Others
were exposed to females they didn't like." As part of her research
she collected semen samples to see if sperm counts were part of
the problem, but she found that "some males had low sperm counts
but managed to breed anyway." She found plenty of reasons for
the gorillas' breeding difficulties, but no overall solution. Yet
she came out of the experience with a specialty: reproduction.
Reproductive studies of zoo animals constituted a new field in
1981, when Schaffer did her postdoctoral work in that area at the
Bronx Zoo. She had no models to follow, so she spent a lot of time
closely observing numerous animals - she even lived on the grounds.
"One of my jobs at the Bronx was trying to figure out how to
determine pregnancy in these animals," she remembers. "They
couldn't always tell." Many exotic animals don't show - for
a good reason. If you're out in the wild and a predator knows you're
pregnant," Schaffer says, "he knows that you're a little
slower than the rest of the herd."
No one knew how to tell for sure where a female rhino was in her
fertility cycle either. "My job was to hang around the rhino
barn and wait for the female rhino to urinate so I could get a urine
sample and test it for hormones." Schaffer was looking for
a link between hormone levels and behavior, and eventually she found
But when Schaffer wanted to start studying the possibility of
artificial insemination in several species, zoo officials balked.
Having grown up on a farm where the procedure was routine, Schaffer
says, "It seemed perfectly natural to me, but in New York they
were a little averse." She thinks they might have been worried
about what the public would think or about being associated with
any kind of research. "It means vivisectionist to some people,"
In 1982 she came to Chicago to act as a consultant. "Tom
Meehan, he's now out at Brookfield, asked me to come and start a
reproductive program on all the exotic animals in this area,"
she recalls. "At that time he was at Lincoln Park, and Lincoln
Park was in the same mind-set [as the Bronx]. It took forever to
convince them that a zoo needs to be a research institution."
This too seemed perfectly natural - zoos are where the wild things
are. If you can't learn from them there, where can you?
Schaffer got a grant to study rhino reproduction and was soon
flying back and forth between zoos in the midwest, as well as Texas,
Louisiana, and Maryland. She built restraint chutes that would allow
zookeepers to easily take blood and fecal samples and do ultrasound
on pregnant females. She also provided more general veterinary care.
Then she and Meehan, who had started in artificial insemination
program at the Saint Louis Zoo for the endangered Speke's gazelle,
were invited specifically to do artificial insemination research
at Milwaukee. "They almost immediately asked me to come work
on their male Indian rhino," says Schaffer. "He didn't
have a mate, and his back feet were bad, and they didn't think he'd
be able to breed. They wanted me to get semen from him and preserve
She's seen rhinos breed. It's a long ordeal, with much chasing,
tossing and pounding - even occasional goring. Rhinos' horns are
hard and very sharp. Rhinos are in the horse family and can run
in short bursts about as fast as a horse - but they weigh a lot
more. During one breeding session at the Bronx zoo, Schaffer had
seen a male toss a female several feet in the air. "I didn't
want to get in the middle of that," she says, "so I wasn't
real sure what they were talking about at first."
And when she saw Rudy, the Indian rhino, she was even less sure.
"Rudy was big for his species. And I'm peeking around this
corner and just seeing this massive animal - and there's no way
I'm gonna get in that cage with that animal. But they said the he
was quite agreeable and cooperative. He really let me come right
into the cage."
She noted the quickest route to the exit and approached warily.
She had no idea how long she'd stay in the pen. She was afraid she
might get stomped - Rudy weighed upward of 4,000 pounds. She might
get a sample, she might not. A straightforward approach had been
successful with other kinds of animals she'd worked with, so that's
what she intended to try first. She crouched partway under his belly.
His knees buckled for a moment - the only time that would ever happen
- but otherwise he barely moved.
"The first time he ejaculated he was in a full erection,"
Schaffer says, "and he ejaculated all this clear fluid. I said,
'Eureka, a sample!'" And that's when Schaffer ran up against
the second big problem with rhino artificial insemination. The sample
didn't have any sperm in it.
Schaffer agreed to return once a week for a while and keep trying.
A couple of months later, on Saint Patrick's Day, Rudy gave a sample
with a little sperm in it. "We were all excited because we
thought, well, this is really going to be it. We're going to get
semen and freeze it, and it's just going to be wonderful. So we
went out to the bar and drank green beer."
But the following week she got the clear fluid again. And the
week after that. For a year. Then into another year. "He was
a very patient beast," Schaffer says.
She continued to drive up to Milwaukee from Chicago once a week.
"I knew sperm was there, because once in a while he'd give
me a drop with sperm in it. I'd think, OK, now the gates are open."
But they weren't.
Schaffer tried practically everything to get Rudy to come across
with a usable sample. She tugged on him, squeezed him as if she
were milking a cow. Once she did nothing but massage his rectum
for an entire day. He ejaculated 400 cubic centimeters of fluid
- without a single sperm in it.
Schaffer rigged up an artificial vagina that's commonly used for
horses, which is just a big bag with warm water in it. "It
was so heavy that we had to attach it to him to hold it up. So he
had it roped to his belly. He was very patient with the whole process.
He'd take a few steps, then he'd stop because he realized there
was something on his belly. Then he'd take a few more steps, and
it started flapping against his belly. He just didn't like that
at all. So we finally had to take it off him."
Schaffer was doing all this during the day, during normal zoo
hours, every week for two years. Spectators could see what she was
doing, but no one ever said anything or asked anyone about what
the slender woman with the short hair was doing with Rudy the rhino.
"I'd be out in the pen just working away, and the public would
be out there watching me. I kept asking Bruce, who was the veterinarian
at the time, 'Is this really a good idea?'" But no one said
it wasn't. "Most people probably thought that Rudy was having
a baby," she says. He wasn't even coming close.
One day in 1985, for reasons Schaffer still can't explain, Rudy
gave a sample that was practically all sperm. She stayed calm. It
could have been another false alarm. But the following week the
same thing happened. And the next. "It was almost as if he
learned to pass go. It didn't stop and it came almost directly from
the vas deferens and didn't mix with any accessory gland fluids.
So it was high concentrations - in the billions. Billions and billions
of sperm." Strangely, this fluid wasn't the result of his normal
ejaculation, which was a hard spray, enough to fill a Dixie cup.
"It was kind of a dribble at that point. Highly concentrated
Stranger still, Schaffer soon discovered that she didn't even
have to touch Rudy to keep the samples coming. "He was doing
it himself," she says, shrugging. "He would get an erection
at the sound of my voice, so when I hit the barn I really had to
get to his cage fairly quickly and get a cup under him - or the
sample was just lost."
Schaffer has worked with a lot of male rhinos since then, and
like Rudy, they've been easy to manipulate and they almost always
ejaculate, though more often than not the sample contains no sperm.
(She doesn't know whether that's normal for mating males, but she
says the species all seem to breed just fine in the wild.) But none
of the bred males has responded to her voice the way Rudy did. She
isn't sure why, though does point out, "I haven't worked with
my others for that long." And none of them has even given anywhere
near as much sperm. "It wasn't a normal ejaculate, obviously,
because the two factions were separate from each other." She
thinks that might be something characteristic of Rudy's species
or simply of him. "I've worked on white rhinos for long periods
of time and not even gotten anything at all."
Rudy is still the best rhino Schaffer's ever worked with. "My
friends like to call him the perfect rhino."
In 1987 Schaffer was in Baltimore working with a bunch of macaques
when she got a call about Rudy, who was then 33. His feet were worse,
he'd developed sores all over his body, he was in awful pain. He
would be put to sleep the following day. Schaffer was on the next
When she walked into his cage, Rudy, pumped full of painkillers,
was lying on his side. She'd never seen him like that, and she thought
he almost looked dead. But when she walked over to greet him, he
became aroused, just as he had for two years. "I said, 'No
Rudy, not today.' He lost his erection. That amazed me, 'cause I
fully expected him to get up, you know, and go through the whole
nine yards. He did it every time."
Schaffer walked over to the side of the cage and just stood there
looking at him. "He rolled up, got up - and it was very difficult
for him to get up 'cause his feet had gotten so bad. He kind of
started walking toward me and came up and put his nose next to the
side of me and kind of pushed me. And I was like, OK? I just stepped
over a little bit. He pushed me again, and he did this all the way
around the cage until he pushed me out the door. I was like, this
is really bizarre. The veterinarian had gotten there by that time,
and he said, 'It's time.' So they went ahead and euthanized him."
She still has a hard time talking about Rudy's death. "He
was in terrible pain, and we were taking him out of his pain. But
after we autopsied him we still weren't sure what the problem was,
and that was the worst part - not knowing."
Since Rudy's death Schaffer has become a traveling emissary pressing
for the establishment and protection of rhino preserves in Indonesia
and India. In addition to starting SOS Rhino, she has lectured government
officials about the necessity of enforcing the ban on the rhino-horn
trade and instituted research programs from Madison to Malaysia.
She's now working with the Henry Vilas Zoo in Madison, the Sedgwick
County Zoo, and the Milwaukee County Zoo, collecting semen from
males that will never get a chance to breed and cryogenically freezing
it for the day when she'll be able to use it. They don't have mates,
she says. "We have too many males now, and we have to save
their genetic material. And this is really one of the options for
doing that. I've been doing this for 15 years. I don't have another
15." She's also collecting sperm at Sungai Dusun, a part of
the Malaysian national park system outside Kuala Lumpur, where she
works with five Sumatran rhinos - a male and his harem of four females.
And she has collected sperm for rhinos that have died at the Brookfield
The benefits to humanity of saving rhinos from extinction are
hard to quantify. Asked in a Web-site interview why she's working
to save them, Schaffer answered, "No matter how hard we try,
we cannot 'build' nature. We can build another bridge, paint another
picture, but we cannot make another rhino. Look into a really wild
animal's eyes. When the wild things are gone, we will lose our place,
our way; for whose eyes will we look into to find our humility,
We've never lived on a planet that didn't have rhinos. Artificial
insemination may or may not save them. Schaffer worries about how
people view her work in this area. "I'm trying to save these
rhinos for posterity. People forget the purpose and just remember
the process. But it has a higher purpose."
The amount of frozen rhino sperm that Schaffer has stored is still
small. So on a mild December afternoon she's at the Milwaukee County
zoo teaching a veterinary student from Madison what she's learned
about collecting it.
An entire family of black rhinos lives at the zoo. Brewster, Pombe's
father, is placidly eating carrots in his cage. Barley is asleep
in hers. Pombe, the rhino that leaped straight into the air and
then slammed into the bars of his cage to attract Schaffer's attention,
strolls off to the far end of his cage, backs up against the bars,
and lets loose a hard spray of white, acidic urine.
"See all this mottling?" says a zookeeper named Dave.
He points to white splotches all over the floor and up and down
the bars of the cage. "That's all rhinos. We have elephants
in here for years, and nothing. But put the rhinos in for a few
months..." His voice trails off. Yet he and everyone else at
the zoo agree that the two-year-old Pombe has very good manners.
Schaffer pats Pombe on the snout. Then she and the student step
into Brewster's cage. Schaffer has been working with Brewster for
a year, but he's never given enough sperm to freeze. This time maybe
they'll get lucky.