Mammals

wildlife preserve in India. Like the African lion, they've suffered from

the destruction of wild lands and from over hunting.

Once, people thought that Asian lions had shorter manes than African

lions, but that's not the case. Both can have either long or short manes.

WOLVES

COYOTE: PLACE IN THE FOOD CHAIN

Every animal on earth lives by eating some other living organism --

plant or animal. The sequence of eaten and eater is called a food chain.

The ultimate source of the energy contained in food comes from the sun. It

is stored in the grass, and passed on to the grasshoppers. The alligator

lizard, which eats the grasshopper, is the next link in the food chain. It,

in turn, is eaten by a roadrunner, which then falls victim to the coyote.

The coyote is called an ultimate consumer because nothing hunts it for

food.

But this food chain is a closed circle, the final link -- coyote --

being fastened to the first -- the grass. When the coyote dies, its

chemicals are broken down by bacteria and returned to the soil, where they

nurture more plant growth.

Like many wild dogs, the coyote is usually active at night, when it

can hunt safely. You can often see a coyote in the early evening and

morning, as it goes to and from its nighttime activities.

Coyotes can run as fast as 40 miles per hour, and at slightly slower

speeds, they can run for miles. If a coyote can stay close to its prey, it

has a good chance of getting a meal.

DHOLE

In hunting style, the dhole is like the hyena. It hunts in a pack with

other dholes, whining, barking and whistling as they go. Whistling usually

means that the hunt is unsuccessful, and the pack should reassemble for

another try.

It is almost impossible for a single dhole to kill a deer, but five to

twelve dholes can manage it together. After the kill, dholes compete for

the morsels by eating very fast. A dhole can chew up almost nine pounds of

meat in an hour.

Strong, wise, brave -- all these words describe the gray wolf. But

another word needs to be added to the list: endangered.

Two hundred years ago, the gray wolf roamed throughout North America.

But many of them were shot by European settlers and pioneers, who were busy

cutting down the wolves' forest home for houses and towns. Those wolves

that remained found fewer deer, moose and beaver to eat.

Today, the gray wolf continues to feel the impact of an expanding

human population. That, and the popular belief that wolves shouldn't live

near humans, continues to threaten their presence on our planet.

GRAY WOLF

Did you know that the gray wolf is the largest member of the dog

family? Apart from man, it once was the most widespread mammal outside the

tropics. As humans move into its habitat, the wolf had to move out.

Did you know that after humans, wolves may be the most adaptable

creatures of all? They're able to live in a wider variety of climates and

habitats than most other animals and can survive on many different kinds of

food.

BEST LEFT UNPROVOKED

Wolves prey on many species in the north -- musk ox, caribou, moose,

deer, hares and even rodents. These carnivores are among the most maligned

of all animals, victims of false myths and legends and systematic programs

of extinction. They are accused of attacking humans and destroying entire

herds of domestic animals. But their depredations of livestock are less

severe than often claimed. And unprovoked attacks by healthy wolves in

North America on humans are unknown. Those recorded from Europe's Middle

Ages are thought to have been by rabid animals or hybrids.

The world will be a far lonelier place if the last wolf dies. As

biologist Ernest P. Walker wrote in his book, MAMMALS OF THE WORLD, "The

howl of the wolf and coyote, which to some people is of more enduring

significance than superhighways and skyscrapers, should always remain a

part of our heritage."

PRIMATS

APES: FUTURE

The future of apes is up to us. All of the great apes are already on

the endangered species list, and all of the lesser apes are as well.

Scientists who have studied them agree that all great apes will soon die

out in the wild unless steps are taken now to protect them.

Gorillas and orangutans appear to have no natural enemies, and

chimpanzees have very few. Gibbons, because they move so fast and live so

high up in the trees, are safe from any animal. Nothing could threaten any

of the apes with extinction until man started hunting them, capturing them,

and destroying the wild lands in which they live.

Today, hunting of apes is against the law everywhere, and there are

strict regulations controlling the capture of wild apes. But illegal

hunting and trapping continues. And the greatest threat of all -- the

destruction of wild lands -- grows greater every day. Tropical forests are

being cut down faster today than ever before ... at the rate of one acre

every second, according to a recent report. At this incredible pace, the

homes of many wild creatures -- including apes -- are simply disappearing.

Most endangered of the apes are the mountain gorillas. Today, there

are less than 500 in Central Africa.

And the other apes are not much better off. Nobody is really sure how

many pygmy chimpanzees or bonobos survive in the jungles south of the Congo

River -- but it is probably less than 10,000. There are fewer than 5,000

orangutans still alive in scattered areas of Borneo and Sumatra. And the

numbers of lowland gorillas and chimpanzees are declining rapidly.

Fortunately, there are people who are trying to save the magnificent

apes. In Central Africa, governments are working to protect the last

remaining homes of mountain gorillas. They have even organized guards that

patrol the borders of gorilla preserves to keep the gorillas safe from

hunters. The World Wildlife Fund and other groups are raising money to buy

land and make sure that it will never be taken away from gorillas,

chimpanzees, orangutans, and gibbons. And scientists everywhere are

studying the apes to find new ways to help them.

BONOBO OR PYGMY CHIMPANZEE

Biologists who have studied the behavior of these animals say they are

the smarter of two species of chimpanzees. Their hair is parted at the

middle and wisps out to the sides of the head, giving them an obvious

physical distinction from the common chimpanzee.

Both species of chimps are intelligent. They belong to the select

animals that make and use tools. You might see a chimp defend himself with

a tree branch, or take a twig and turn it into a useful devise for

gathering or eating foods. Chimps also communicate with many gestures and

vocalizations.

People may feel especially drawn to chimps because of some similar

behaviors. Young chimps laugh when they're tickled. Bonobos quarrel over

food, but hug and kiss to make up.

BONOBO: WORKSHOP IN CONSERVATION

The bonobo or pygmy chimpanzee, is one of only four living species of

great apes. The other three species, the gorilla, orangutan, and common

chimpanzee, have received far greater attention until now. Not even

recognized as a separate species until 1929, the bonobo still remains much

of a mystery in its native habitat, the central rain forests of Zaire.

Often confused with the common chimpanzee, the bonobo is only slightly

smaller but has a more graceful, slender body; the head is smaller but the

legs are longer than those of common chimps. The most outstanding physical

difference is the bonobo's hairstyle, an attractive coiffure of long black

hairs neatly parted down the middle. To the experienced eye, the difference

between the chimpanzee and the bonobo is as great as the difference between

a leopard and a cheetah.

The bonobo is as rare in zoos (there are less than 80 in captivity

worldwide) as it is in the wild (estimates range from 5,000 to 20,000). In

1989, the entire San Diego Zoo group of 11 animals was relocated to the

Wild Animal Park.

No effective conservation plan for the bonobo could be developed

without firsthand knowledge of the only country that is home to this

critically endangered ape. International conservation projects are as much

a people issue as an animal issue; therefore, the needs of the local

Zairian people must be taken into account. Political, cultural, and

economic problems are just as important to consider as the biological needs

of the species we are attempting to save. For these reasons, the San Diego

Bonobo Workshop continually emphasizes the need for an international

cooperative effort with the people and government of Zaire.

In light of the increasing awareness of the need to preserve the

world's biodiversity, it is quite surprising how little attention Zaire has

received. The extent and variety of the biological resources in Zaire's

forest ecosystems is matched by few other tropical countries. After Brazil,

Zaire has the second largest tropical forest in the world. Despite this

fact, Zaire is among the last of the countries in the tropical forest belt

without a comprehensive program to protect its tropical forest. Programs

like the one developed at the San Diego Bonobo Workshop will be

instrumental in obtaining funds from organizations like the World Bank to

protect the bonobo and its forest habitat.

THE GORILLA SUBSPECIES

Three subspecies of gorillas are currently recognized. Almost all zoo

gorillas are western lowland gorilla (Gorilla gorilla) native to west

African nations such as Cameroon, the Central African Republic, Gabon,

Nigeria, and Rio Muni. The total population of western lowland gorillas is

estimated to be between 30,000 to 50,000 individuals, and they are

classified as threatened by the IUCN (International Union for Conservation

of Nature and Natural Resources). Studying these gorillas in the wild is

extremely difficult, because their preferred habitat is dense jungle.

A very few eastern lowland gorillas (Gorilla gorilla graueri) native

to eastern Zaire, live in zoos. Mbongo and Ngagi, the two "mountain

gorillas" who lived at the San Diego Zoo in the 1930s and 1940s, would now

be classified as eastern lowland gorillas. These gorillas are considered

the largest subspecies on average, and generally have blacker hair than

western lowland gorillas. They number approximately 3,000 to 4,000 and are

classified as endangered.

No mountain gorillas (Gorilla gorilla beringei) exist in captivity,

but these are the most-studied gorillas in the wild. They live in the

mountainous border regions of Rwanda, Uganda, and Zaire. Only about 600

individuals exist, in two separate populations, and they are classified as

endangered. Mountain gorillas are distinguished physically by their large

size and extra-long, silky black hair. A number of skeletal differences

exist between the three subspecies as well.

It would be interesting to see if DNA sequence comparisons could help

us understand the phylogenetic (evolution of a genetically related group as

distinguished from the development of the individual organism)

relationships of the gorilla subspecies. This could help anthropologists

understand the mechanisms and rates of primate evolution. It could also be

important if gorilla populations ever become so critically depleted that

interbreeding of different subspecies were contemplated. At CRES, we are

comparing DNA sequences from gorillas of all three subspecies. Only a few

gorillas have been tested so far, but to date it appears that the

relationships between the subspecies generally follows the geographic

location of populations.

Western lowland gorillas have a large range, and many DNA sequence

differences exist between different individuals of this subspecies. Western

lowland gorillas are separated by 600 miles from eastern lowland gorillas,

and substantial sequence differences exist between the two groups as well.

The eastern lowland and mountain gorilla populations are found relatively

close together, but they have been isolated from each other for an unknown

amount of time. They are presently separated by substantial geographic

barriers: portions of the Rift Valley and a variety of mountain ranges.

However, we find much less genetic difference between the eastern lowland

gorillas and the mountain gorillas than there is between certain western

lowland gorillas. The distinct physical differences between eastern lowland

and mountain gorillas probably reflect recent adaptations to their

respective habitats -- lowlands versus mountains -- and not a distant

genetic relationship.

LION-TAILED MACAQUES: BACKGROUND

The macaques, a genus of some 13 to 20 species (there is disagreement

among taxonomists on the actual number), are found in North Africa and

throughout southern Asia from Afghanistan to Japan. The most familiar form

is the rhesus monkey, which is often seen by tourists in the towns and

cities of India. Fossils dating to six million years indicate that the

macaques originated in northern Africa and once roamed over Europe as far

north as London. These earlier macaques were not very different in

appearance from the Barbary monkeys that survive today in Morocco, Algeria,

and on Gibraltar. However, once the Macaques reached Asia, at least by

three million years ago, they diversified into a variety of forms. Few are

as distinctly different as the lion-tails, with their black coats, silver

facial ruffs, and strongly arboreal habitats. Lion-tails are one of the two

macaque species that are listed as in danger of extinction, but we may

realistically expect the Tibetan, Formosan, and Sulawesian species to fall

into that category before the year 2000.

Their geographical range snakes along the slope's and highest crests

of the Western Ghat Mountains where, today, the forest is reduced to about

one percent of the total land cover. Like its captive counterpart, the wild

living lion-tail was ignored by primatologists until well into the 1970s.

Although opinions vary, most would agree that the wild population today

numbers between 2,000 and 5,000 individuals. Initial field reports indicate

that wild lion-tails prefer to spend about 99 percent of their time in the

trees. Like other macaques, their diet is dominated by wild fruits, but

includes a variety of flowers, leaves, buds, grasses, insects, and even a

few nestlings of birds and mammals. One of the more interesting forms of

feeding reported by Dr. Steven Green of Miami University involves a simple

form of tool use. In order to protect their hands while feeding on stinging

caterpillars, lion-tails have been seen to pluck large tree leaves and lay

them over the caterpillars before pouncing on them.

In the wild state, lion-tail groups average about 20 individuals,

usually with more than a single adult male present. Males are larger than

females by about a third and are typically ranked relative to one another

in a social hierarchy. Males usually emigrate from their natal group to

join another during the early stages of adulthood. Being macaques, lion-

tails are intensely social and are highly aggressive toward unfamiliar

individuals. Preliminary work on our captive population indicates that much

of the behavior between group members is dependent upon one's relationship

to a small number of female-headed lineages. It is possible to have up to

four living generations within each matriline and four or five matrilines

within a group. Dominance relationships among and within matrilines play a

crucial role in the everyday life of females and their offspring, as they

do for adult males. One's social position determines access to essential

resources such as food, perches, and social partners.

LION-TAILED MACAQUES: FUTURE PLANS

This highly endangered primate has been exhibited at the San Diego Zoo

since 1923. In 1979, the existing population of three males and three

females was relocated to the Primate Research Pad for concentrated study of

their reproductive biology. Within the next decade their reproductive

cycles were characterized, as were their sexual and social behavior,

parturition and infant rearing, and various other aspects of the captive

experience. Nearly a dozen scientific papers from these studies have been

published in peer-reviewed journals or as book chapters.

BY 1989 the Zoo's captive population had grown to 38 individuals. This

same year the program undertook a significant change in direction. Seven

individuals, including five born at the Primate Research Pad, were released

into a state-of-the-art exhibit in Sun Bear Forest. Although these

individuals are no longer under study, it was knowledge gained over the

previous decade that contributed to the design of an exhibit facility

which, by anyone's criteria, is an outstanding success.

A second troop of 11 individuals was simultaneously relocated to the

newly constructed 3/4-acre breeding kraal at the Wild Animal Park. It is

this population which will be a major research focus during the next five

years. This troop has been exempted from Species Survival Plan management,

a program of the American Association of Zoological Parks and Aquariums,

providing freedom to pursue several interesting lines of inquiry. One of

these has to do with the impact of traditional management regimes on

certain life history parameters. The second investigation will pursue

experiments designed to prepare the troop for reintroduction to suitable

habitat in India in five to seven years.

The lion-tailed macaque is by nature a highly social mammal. Group

members are organized in a social hierarchy that appears to remain stable

over many years. Individual troops are highly xenophobic. This trait,

combined with natural aggressiveness, results in potentially fatal conflict

when new individuals are introduced. In the wild state, males will leave

their natal troop at sexual maturity and join a new one. Females remain in

their natal troops throughout their lives.

Transfer by males is accompanied by a substantial amount of

aggression, but is presumably a necessary event to preclude inbreeding.

These natural attributes of wild troops would seemingly have profound

implications for the transfer of individuals, especially of females,

between zoological institutions to satisfy genetic and reproductive

objectives.

It is relevant to ask if the ongoing disturbance of the social order

through frequent inter-institutional transfers might negatively impact on

such parameters as infant mortality, female fecundity, and perhaps even the

neonatal sex ratio. Our kraal group has been together for the past 24

years, the only social disturbances having been the replacement of breeding

males. We have learned how to integrate new males into groups with a

minimum of social upheaval. We therefore have a unique opportunity to

compare findings from our relatively undisturbed population with those from

more traditionally managed populations in other zoos over the next several

years.

Preparation of this same troop for reintroduction to the wild has two

components. The first entails a number of experimental procedures designed

to "teach" natural foraging, avoidance of predators (including humans), and

appropriate social cohesiveness. In addition, the troop must be routinely

evaluated for any pathogens that would pose a hazard to the existing wild

population.

The second component is evaluation of potential release sites in the

wild. The area selected for a test-case reintroduction must not only be

protected from human activity, but must contain adequate food and shelter

to insure the long-term survival of the troop. CRES anticipates working

closely with Indian colleagues on this aspect.

NIGHTTIME IS THE NORM: LABOR AND BIRTH IN THE LION-TAILED MACAQUE

Lion-tailed macaque neonates (newborns) are born with black fur, and

their faces, hands, and feet are pink and hairless. Their characteristic

silver manes do not begin to grow in until the babies are several weeks

old, and their faces gradually acquire the black pigmentation of adults.

When the lion-tailed macaque breeding and management program began at

the CRES primate facility more than ten years ago, little was known about

the gestation, labor, and delivery of infants in this species. There was

extensive documentation of parturition in some other macaques, but no

comparable data were available on the much rarer lion-tailed macaque. How

long is the normal gestation length? At what time are births most likely to

occur? How long does labor last? What factors indicate that there may be a

delivery problem requiring veterinary intervention? Answers to these and

other important questions were needed in order to ensure the best captive

management procedures and to maximize the breeding success for this

species.

The primary reason these data had not been collected previously is

that most new infants were usually discovered in the morning, after the

keepers arrived at work. We began collecting data on each lion-tailed

macaque birth by setting up 24-hour "birth watches" that began several days

before the dam was due to deliver. Conception dates were determined

partially through hormone data from daily urine samples, and also by

keeping careful track of menstruation, sex-skin swellings, and mating

episodes. Parturition-date predictions were based on the 168-day gestation

length documented for the rhesus macaque. However, because this is an

average length, we began our observations about ten days before the due

date in order not to miss the early deliveries.

The birth watch involved round-the-clock observations at 15-minute

intervals during successive, 4-hour shifts. Observations were recorded by

keepers, technicians, and trained volunteers. As soon as any signs of

straining or birth fluids were noted, continuous notes were kept and each

subsequent contraction or birth-related event was timed and recorded.

Behavioral indications of impending labor included restlessness and manual

exploration of the vaginal area. Although these signs eventually proved

reliable, we used the first, clear contraction as the starting point for

measuring the duration of labor. (In human terms, this is equivalent to

second-stage labor. The usual criterion of first-stage labor, cervical

dilatation, cannot be observed in the wild primate unless restraint is

used.) During actual labor, several straining postures were noted; most

common were variations of squatting postures and arched-back stretches.

The first birth was to an experienced mother (this was her third

delivery) and was documented on videotape. After nearly 8 full hours of

labor and 188 contractions, the dam gave birth to a healthy, female infant.

These initial observations led us to believe that a labor of this duration

was not a basis for concern; however, we soon learned that this was far

beyond the average labor length and number of contractions common for this

species.

Over an 8-year period, we were able to collect data on 18 births from

8 different mothers in our colony. Our program has provided some valuable

information about species-typical birth patterns that we can now use to

direct management decisions. We found that the average length of labor to

expulsion of the fetus was about 2 hours and 15 minutes, and the shortest

labor was only 50 minutes total. The female that required eight hours to

deliver in the first case observed then delivered her subsequent infant in

only a little over an hour! Although our sample is still small, it would

appear that, on the average, first-time mothers have longer and more

difficult labors.

Our study determined that the average number of contractions to

delivery for lion-tails was 54. The female with the longest labor also had

the largest number of contractions (454). In her next delivery, the infant

arrived after only 14 contractions, the lowest number recorded during the

entire birth study. Based on the average number of contractions seen in 17

successful deliveries, and one ending in stillbirth, contraction

frequencies approaching 75 to 100 in number may serve as a warning that

intervention will be necessary.

The average length of gestation for 14 pregnancies in our colony was

169.5 days, with a range of 163 to 176 days. This is very similar to what

has been reported for other macaques. Our observers quickly discovered that

those who watched during the 7 to 11 P.M. shifts were the most successful

at being present when births occurred: labor began between the hours of

7:15 P.M. and 3:15 A.M. in every case but one. The exception was one first-

time mother that began straining in the early afternoon. This female had a

difficult labor, and a dead fetus was later removed by cesarean section

after 8 hours of straining and 193 contractions. All the other births

resulted in live offspring and occurred between the hours of 8:05 P.M. and

6:28 A.M. Based on previous primate birth records, daytime births are not

the norm and may indicate an increased risk to both fetus and dam.

Expulsion of the placenta always took place within about 20 minutes

after parturition, and usually it was immediately consumed by the mother.

In a few cases, first-time mothers carried the placenta around for several

hours, along with the infant, until it could be removed by keepers.

Whenever possible, a sample of the placenta is saved for analysis by Zoo

pathologists, who check it for abnormalities. After delivery, the mothers

carefully lick the birth fluids off their infants, and the neonates begin

nursing within a few hours. Each and every female in the study provided

excellent maternal care immediately following parturition.

The lion-tailed macaque breeding colonies are now located in the Sun

Bear Forest exhibit at the Zoo (one adult male and six females) and in a

large, off-exhibit kraal at the Wild Animal Park (one adult male, two

juvenile males, one infant male, and ten females). Together these represent

the largest captive group of lion-tailed macaques in the world -- about 20

percent of the total captive population. Eight years of patient monitoring,

birth watches, record keeping, and evaluation have brought us a long way in

the breeding and captive management of this macaque species.

ZOONOOZ, May, 1990 "Nighttime Is the Norm: Labor and Birth in the Lion-

tailed Macaque," by Helena Fitch-Snyder, Animal Behavior Specialist/CRES

and Donald Lindburg, Ph.D. Behaviorist/CRES.

МЕНЮ

Mammals