Finding the right way to thank a donor can be tough—but in the case of one recent gift, the Wildlife Conservation Society has come up with a particularly cute way to show its appreciation.

Margaretta Taylor, a New York philanthropist, donated $5-million to the environmental organization, which runs the famous Bronx Zoo.

As an expression of gratitude, the Wildlife Conservation Society has decided to name a baby sea lion, born at the zoo last month, Margaretta in Ms. Taylor’s honor.

Among Ms. Taylor’s other gifts: more than $3-million to the Memorial Sloan-Kettering Cancer Center for research, and last year, with her family, $4-million to American Rivers, an environmental organization in Washington.

Photo: Julie Larsen Maher for the Wildlife Conservation Society