San Diego Zoo welcomes 19 Pacific Pocket Mouse pups
SAN DIEGO (KUSI) — The San Diego Zoo welcomed 19 endangered Pacific Pocket Mouse pups already this breeding season, which began in February.
Their stages of development range from pups that are blind, pink, hairless and weigh less than 2 grams, to pups that are 4 grams, beginning to wean from their mother and forage for seeds on their own.
The Pacific pocket mouse is the smallest mouse species in North America, and adults typically weigh between 6 and 7 grams.
The gestation period for a Pacific pocket mouse is 23 days, and the species can reach sexual maturity in about 41 days. Because of this, pocket mice that are born this season could reproduce and give birth or father pups this season, too.
“People think ‘mouse’ and they think of a pest in their house, but these are native California rodents that don’t reproduce like crazy,” said Debra Shier, Ph.D., Brown endowed associate director of applied animal ecology for the San Diego Zoo Institute for Conservation Research. “Pacific pocket mice are critical to their ecosystem function, because they are seed eaters and disperse the seeds of native plants. They also dig burrows that hydrate and increase nutrient cycling.”
The Pacific pocket mouse was thought to be extinct in the 1980s, but it was rediscovered in the wild in 1993. Starting in 2012, 30 adult Pacific pocket mice were taken from the three remaining wild populations to participate in a breeding program at an off-exhibit area at the San Diego Zoo Safari Park. Today, scientists at the breeding facility are caring for more than 125 Pacific pocket mice.