Record Weight and Physical Profile of the Heaviest Giraffe
The heaviest giraffe ever documented is a Masai bull named Phil, who lived at the Chester Zoo in England. Phil reached an estimated body mass of roughly 1,200 kilograms, making him the fattest giraffe on verified zoo records. His height was around 5.7 meters, and his body condition reflected above-average muscling and fat deposits for the species. This profile is based on zoo management logs and veterinary assessments cited by the zoo and wildlife organizations chesterzoo.org.
Masai giraffes, also called Kilimanjaro giraffes, are the tallest subspecies and often carry more mass than other subspecies. Adult males typically weigh between 800 and 1,200 kilograms, while females range from 700 to 1,000 kilograms. Phil's weight placed him at the top of this range, and his body mass index, calculated from height and weight data, was higher than the average for adult male Masai giraffes in European zoos bristolzoo.org.uk.
Comparison With Other Heavy Giraffes and Species
Rothschild and Reticulated Subspecies Weight Ranges
Rothschild's giraffes and reticulated giraffes generally weigh less than Masai giraffes, with adult males averaging 900 to 1,100 kilograms. The heaviest recorded Rothschild bull weighed around 1,050 kilograms, while the fattest reticulated male was close to 1,080 kilograms. These figures come from studbook data maintained by the Association of Zoos and Aquariums and the European Association of Zoos and Aquaria aza.org.
Body Condition Scoring in Captive Giraffes
Zoos use a five-point body condition scoring system to track weight and fat distribution in giraffes. Scores above four indicate excess fat, and Phil consistently scored four to five during his later years. Keepers adjusted his diet to reduce caloric intake, but his baseline mass remained higher than that of most male Masai giraffes in managed care aza.org.
Why Some Giraffes Reach Extreme Weight
Diet and Enclosure Factors
In captivity, giraffes receive hay, pellets, fruits, and vegetables, which can increase calorie intake compared to wild browsing patterns. Enclosures with limited space reduce daily movement, leading to higher fat accumulation. Chester Zoo provided Phil with a large habitat, but his age and reduced mobility later in life contributed to sustained high body weight chesterzoo.org.
Health Monitoring and Longevity
Regular veterinary checkups, including weight measurements and imaging, allowed keepers to monitor Phil's health closely. His longevity, reaching over 25 years, is above the average lifespan for male Masai giraffes in zoos, which is around 20 to 22 years. The data from his care is shared with conservation programs that study giraffe physiology and welfare bristolzoo.org.uk.