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“The bull, Ahmed, flapped his ears, raised his trunk and trumpeted softly. He was enormous, standing nearly ten feet tall and weighing about 11,000 lbs with a set of 10 foot long, 300 pound ivory tusks. I could clearly see his distinctive long eyelashes and sunken cheeks.  Seeing this great bull alive right in front of me was a spiritual experience, a turning point in my life.  My heart pounded.  I grasped my friend’s wrist and squeezed it so hard that I startled him.  It was at this moment, I believe, that
I decided to devote my life to the study of elephants.”

~ Jeheskel Shoshani

There’s no doubt that bull elephants are the largest land animals alive today.  Their size, strength, vocalizations, intelligence and musth behaviors make them unique in the animal world.  The AZA Elephant TAG/SSP and AZA Standards for Elephant Management and Care strive to provide excellence in elephant care for both bulls and cows.  But, bull elephants are different: bull nature is usually competitive, rather than affiliative like the cows.  The information below is adapted from the Elephant Resource Manual and is a guideline for caring for and managing bull elephants in AZA institutions.

Bull Social Units

The AZA Standards for Elephant Management and Care state:

If males are housed, separate facilities for isolation must be available, and a program of social contact in place. Males (six years and older) may be housed alone, but not in complete isolation; opportunities for tactile, olfactory, visual, and/or auditory interaction with other elephants must be provided. In the wild, adult males are primarily solitary. However, they do have regular contact with other elephants.

Each institution must be able to demonstrate and/or describe how they would successfully isolate and socialize males.

In the wild, bull elephants are pushed out of their family groups as they enter their teenage years.  Adult bulls spend a majority of their time away from cows except during breeding times.  Bulls, once separated from the natal group, will form loose associations with other bulls except while in musth, at which time they are solitary.  However, they are constantly in chemosensory (scent) and infrasonic communication (low-frequency calls) with other elephants in their area.

Adult bulls go through periodic episodes of elevated hormones (testosterone) and heightened aggressive states called musth. Musth bulls can be recognized by the large amounts of fluid draining from the temporal glands located just behind the eyes. Many bulls continually dribble urine and show damp patches on their hind legs.  Musth bulls also show several unique behaviors including ear-waving
to spread the musth scent, a musth rumble (or low frequency vocalization announcing his presence to cycling cows), a musth walk with head and ears held high above their shoulders as a visual display to other bulls, and aggression towards everything in its path. All of these make the musth bull a formidable opponent.

In the wild, young bulls spend time learning the capabilities of other bulls in their area and establishing a social hierarchy and status. Bulls in the wild may not be competitive enough to breed until they are almost 30 years old, due to the presence of bigger, stronger bulls in the region. As they age and grow larger, thus able to compete effectively for breeding opportunities, the bulls appear to spend their time eating and seeking out cows. Although we don’t fully understand the complex behavioral function of musth, musth bulls are frequently successful suitors for cycling cows. 

Moving a young bull from his natal group and introducing him to other young bulls or unfamiliar cows as he matures mirrors the experiences of elephants in the wild. This may stimulate species-specific male behaviors and reproductive capabilities. 

Bull Elephant Care Facilities

Elephants need contact with other elephants to develop correct social behaviors, optimal environments to have positive interactions with other elephants, and choices for staying active. Young bulls should be housed and cared for in groups with cows.  Properly socialized elephants may integrate into new situations quicker and can be more successfully introduced to a larger herd than animals with limited or no previous social contact with others.

It is recommended that all AZA facilities maintaining elephants provide habitats and indoor areas for bull elephants.  Because the North American population of Asian and African elephants is not self-sustaining, increased breeding efforts are needed.  Increased efforts require more facilities to care for adult bull elephants for breeding, as well as to care for bull calves that will result through increased reproduction. In addition, prior to breeding all AZA facilities should have facilities or plans for facilities, that will accommodate bull elephants in the event that a male calf is born.

Adult bull elephants must be cared for in facilities that are capable of dealing safely with their potentially aggressive behavior, especially during their intermittent musths which can produce erratic, unresponsive and aggressive behavior. 

Caring For Bulls

Proper enrichment and training are vital to an elephant's care and well being.
The training of specific behaviors ensures both physical and mental stimulation. 
In effective training programs, elephants are willing participants in the training process.

In virtually all situations, with some exceptions, adult bull elephants should be managed in an environment where the elephant and its handler interact through a barrier.


The AZA Standards for Elephant Management and Care state:

Each male and female elephant of potential reproductive age must have an initial reproductive assessment and follow-up assessments on a regular basis by transrectal ultrasound, and all female elephants of potential reproductive age must have their progesterone cycle monitored to verify current reproductive status and assess overall reproductive health.

In introducing bull elephants to cows, it has been found that all bulls react differently from day to day, from musth period to musth period, and from cow to cow.  Therefore, there is not “one way” to introduce bull elephants to cows. Rather, there are many ways based on individual reactions of the bulls, observations of the caretakers and past experience.

Semen collection to assess reproductive viability should be done on at least an annual basis and testosterone levels should be monitored regularly. This will help to monitor the health, maturity and fertility status of each bull through its lifespan.  Assessing immature bulls will provide important data on the maturation process and may have the potential to predict their reproductive soundness as adults.

Semen collection protocols should be obtained through the Elephant TAG/SSP.


The AZA Standards for Elephant Management and Care state:

AZA Zoos should contribute to in situ and ex situ conservation and research efforts. AZA zoos that currently exhibit or desire to exhibit elephants should make every effort to maintain elephants in their collections so that they can contribute to conservation through public education, scientific research and
the support of field conservation.

Past and Current Research includes:

  • Comparative Analyses of Seminal Plasma from Asian and African Elephants
  • Behavioral Enrichment for Solitary Male Elephants
  • Development and Identity of Sexually Dimorphic Reproductive Signals and Responses by African Elephants
  • Characterization of Elephant Seminal Trials
  • Cryopreservation of Elephant Spermatozoa
  • Monitoring Elephant Reproduction in Zoo Elephants
  • Standardization of Assessment Techniques for Semen Cryopreservation
  • Chemical Communication and Musth in Captive Male Elephants
  • Understanding the Endocrine Control of Musth in Elephant Bulls
  • The role of musth in reproductive behavior and paternity success
  • The care and welfare of elephants in AZA institutions (including bulls)

Future Research could include:

  • Train more bulls for semen collection.
  • Optimize assisted reproductive techniques, including collection, analysis and processing of fresh and frozen semen, artificial insemination, estrous synchronization, gender selection, seminal pathogen analysis, and development of a genome resource bank.
  • Further delineate the causes of reproductive dysfunction in female (e.g., ovarian acyclicity, reproductive tract pathologies) and male (e.g., poor semen quality, lack of libido) elephants through evaluations of behavioral, physiological, social and environmental factors, and develop appropriate treatments or mitigating strategies.
  • Better understand the basic biology of male and female elephants of both species from prepuberty to senescence to create a physiological database.  Studies should focus on endocrinology (pituitary, gonadal, adrenal and thyroid function), reproductive tract morphology (ultrasound evaluations), semen physiology, pregnancy, parturition, lactation, immune function and musth.
  • Encourage scientific investigation into musth to better understand social, reproductive and husbandry implications.
Professional Members
Elephant Information
Updated: February 22, 2012