Captive Dolphin Mortality: What the Numbers Reveal
• A study in 1985 revealed that of 32 killer whales examined after dying in aquariums around the world, half had died of bacterial infections, and one quarter of pneumonia.

• 53% of those dolphins who survive the violent capture die within 90 days.

• The average life span of a dolphin in the wild is 45 years; yet half of all captured dolphins die within their first two years of captivity. The survivors last an average of only 5 years in captivity.

• Every seven years, half of all dolphins in captivity die from capture shock, pneumonia, intestinal disease, ulcers, chlorine poisoning, and other stress-related illnesses.

• According to the Marine Mammal Inventory Report, an in-depth chronology of dolphins born, imported or exported to and from U.S. facilities, hundreds of US dolphins alone have died in captivity over the years, assuming all were accounted for.

• Sources cite that the number of dolphin deaths worldwide as a by-product of the captivity industry runs well past 1,000, approximately the same number of animals currently being held.

• Common causes of death -which are uncommon in wild species - include: stress-related factors; chlorine toxicity; bacterial septicemia; internal bleeding; zinc poisoning; trauma; chronic esophageal ulcers; allergic reaction to vaccinations; kidney or liver failure; ruptured stomach ulcers; drowning as a result of maternal trauma; accidental collision with tanks or pools; and shock/injury during transport.

• Sea World, perhaps one of the most advanced captive facilities in the world, reported the deaths of 93 dolphins between 1971 and 2002. That's 3 per year at Sea World alone, assuming that all were accounted for.

• When a baby dolphin is born in captivity, the news is usually kept secret until the calf shows signs of survival.

• Although marine mammals do breed in captivity, the birth rate is not nearly as successful as the one in the wild, with high infant mortality rates.