After successful swimming lessons and healthy checkups, three male otter pups are now on exhibit at Oakland Zoo. They were born to Ginger, North American river otter, on the morning of February 24, 2013 at Oakland Zoo. Each baby weighed approximately 0.3 pounds at birth or about 136 grams. They now weigh around 4.5 pounds. The pups are named Kohana (swift), Hinto (blue), and Shilah (brother).
Even though Ginger, otter mom, is being a fabulous mother, zookeepers have been tracking the otters’ growth and health with weekly checkups, which have been referred to as “pupdates.” For the past two months, the pups have been off exhibit to nurse and grow. At this point in time, all three otter pups’ eyes have opened. They are becoming more mobile and vocal as they continue to gain weight and mature. Swimming is not instinctual, therefore, the pups were not on exhibit until they were strong swimmers and reached a certain size.
See a North American river otter pup being taught how to swim (Oregon Zoo):
Zoo guests are able to watch the new pups in their exhibit daily. Currently, Oakland Zoo has a total of seven river otters for visitors to observe and enjoy.
North American river otters actually spend two-thirds of their time on land, yet eat mostly fish, crayfish, frogs, turtles, and other aquatic invertebrates. Otters breed in late winter to spring but the embryos only develop to the blastocyst stage and then they stop developing further until about 9 – 10 months later. Once they start to develop again, gestation is 68 – 74 days. This type of process is known as delayed implantation, and is also seen in polar bears for instance. The pups will start their life in a burrow in a river bank and are born blind and helpless. They are nursed by mom otter for one month and are weaned at about 3 – 4 months; they then begin to venture out of the burrow/den to play and learn how to swim.
(Source: Oakland Zoo press release, 09.05.2013)