The death of a 46-year-old female beluga whale at Canada\'s Vancouver Aquarium was likely age-related, but will be investigated further, officials said. The whale named Kavna died Monday afternoon after showing \"inconsistent behavior\" during the past few weeks, the aquarium said in a release. Blood tests and other veterinary examinations were inconclusive, the facility said. Spokeswoman Charlene Chiang said most beluga whales in the wild have a lifespan of about 30 years, so to live an estimated 46 years in captivity was a \"long and healthy life,\" the Vancouver Sun reported. A 2-day necropsy process began Tuesday to assess factors in the whale\'s death, the report said. The whale came to the aquarium from a facility in Churchill, Manitoba, in 1976. A year later, Kavna had a calf that died of an infection at the age of four months. The aquarium has two other female beluga whales, a mother and calf.