DETROIT (Michigan News Source) – Detroit Zoo workers and animal enthusiasts are mourning the death of Whisker, a 21-year-old otter.

Zoo officials say Whisker came to Detroit in 2009 after being rescued in 2003.

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She and a male Otter named Lucius were inseparable and became the parents of the first river otter litter born at the zoo in 50 years.

As she aged, Whisker started having problems with the function of her hindlimbs.