Social and individual behavior of a group of bottlenose dolphins (Tursiops truncatus) in open and closed facilities.

Abstract

FEW STUDIES ON THE WELFARE OF CAPTIVE BOTTLENOSE DOLPHINS (TURSIOPS TRUNCATUS) HAVE BEEN CARRIED OUT. OF THESE, MOST INCLUDE INFORMATION ON ANIMALS KEPT IN CLOSED FACILITIES OR POOLS. THE AIM OF THIS STUDY WAS TO ASSESS THE EFFECT ON THE BEHAVIOR OF A GROUP OF DOLPHINS BY CHANGING IT FROM CLOSED FACILITIES, WHERE IT HAD BEEN HOUSED FOR NINE YEARS, TO OPEN FACILITIES OR SEA PENS. TEN BOTTLENOSE DOLPHINS (TURSIOPS TRUNCATUS), ONE MALE AND NINE FEMALES, WITH AN AGE RANGE OF 16 TO 24 YEARS WERE OBSERVED. USING A COMBINATION OF SCAN AND FOCAL SAMPLING A TOTAL OF 96 HOURS WERE USED TO OBTAIN INFORMATION ON THE PROPORTION OF TIME ON INDIVIDUAL AND SOCIAL BEHAVIORS IN BOTH TYPE OF FACILITIES. THE RESULTS SHOW THAT DOLPHINS KEPT IN CLOSED FACILITIES SPENT LESS TIME SWIMMING AND MORE TIME FLOATING THAN IN OPEN FACILITIES (P = 0.01). LIKEWISE, THE SWIMMING PATTERN IN CLOSED FACILITIES IS IN CIRCLES (P = 0.009) WHILE IN OPEN FACILITIES THE LINEAR PATTERN PREDOMINATES (P = 0.02). FURTHERMORE, WHILE KEPT IN CLOSED FACILITIES, DOLPHINS SPENT MORE TIME INTERACTING SOCIALLY THAN IN OPEN FACILITIES (P = 0.02). THIS INFORMATION IS USEFUL TO BETTER UNDERSTAND THE EFFECT OF DIFFERENT TYPES OF FACILITIES ON THE BEHAVIOR OF CAPTIVE DOLPHINS.