Life expectancy in four studied marine mammal species has increased by over three times in zoos and aquariums.
Marine mammals live longer in zoos thanks to better animal care
Animal care and management practices at zoos and aquariums have improved markedly and as a result several marine mammal species live longer in zoos than in the wild, say the authors of a new study.
The study, led by Species360 and University of Southern Denmark research scientist Morgane Tidière in collaboration with 41 other experts worldwide, examined life expectancy and lifespan equality among four captive marine mammal species. They have found that these mammals live longer in captivity than in the wild.
Specifically, life expectancy in the four marine mammal species (the harbour seal, California sea lion, polar bear and common bottlenose dolphin) has increased by over three times while the rate of deaths in the precarious first year of life has declined by up to 31% over the last century in zoos and aquariums included in the study. In general, life expectancy of these species is now two to three times longer than their counterparts in the wild.
Although the results of this study are significant, it has long been known that captive animals tend to live longer than those in the wild owing to fewer stresses on them, including untreated diseases and predation. However, this new research has now quantified the disparities in select species.
The researchers say they have “found a significant improvement in longevity and lifespan equality for the four species from the 1990s onwards, which is believed to be a result of advancements in zoological practices, such as implementing advanced veterinary, environmental, nutritional and enrichment measures, as well as the voluntary cooperation of animals in routine examinations through positive reinforcement training.”
These improvements, they say, result from “the establishment of regional and national zoo associations, accreditation standards, coordinated breeding programs, shared databases and professional networks which foster knowledge sharing, thereby collectively improving animal welfare.”
“Our findings indicate that significant progress has been made in enhancing the welfare of marine mammals in zoological institutions, as a result of improvements in management practices in progressive zoos and aquariums. Professional zoos and aquariums of today cannot be compared to zoos 30 years ago,” Tidière explains.
Better animal welfare practices at zoos can yield similarly results for other species as well, the scientists stress.
