(Image credit: © Andrew Reding 2011)
Sea otter reproduction is conducted through internal fertilization, meaning the eggs are fertilized inside the body of the female. Male sea otters mate with more than one female during a year, with breeding taking place throughout the year. Mating practices are both playful and aggressive. The male usually grabs the female's nose in his teeth which often leads to bleeding and swelling. Females can be identified by scientists through the scars that remain (Sinha et all.,1966).
(c) Andrew Reding 20011
(Image credit: © Loren Chipman 2019)
Female sea otters have an unknown gestational period, which is the length of the pregnancy, from five to twelve months, with an average of six months. We do not know for sure because they have an extended period of delayed implantation (Sinha et all.,1966).
(Image credit: © Sam McMillan 2017)
Like all mammals, sea otters nurse their young with milk. Mothers rear their pups for six months without assistance from the father, and after that their offspring are on their own. Females are sexually mature by four years, and males don't typically breed until 8 years of age. (Sinha et all.,1966). See diagram below.
Sinha, A. A., Conaway, C. H., & Kenyon, K. W. (1966). Reproduction in the Female Sea Otter. The Journal of Wildlife Management, 30(1), 121–130. https://doi.org/10.2307/3797891
Chipman, L. (2019). Otter Mom and Pup. Flickr. Retrieved December 18, 2022, from https://www.flickr.com/photos/97902275@N05/46963978774/in/photolist-2ey3EFY-Tp2R5J-Tnmj4c-25av1G6-2655qrF-8e253J-ZjQQ4g-7MM9g3-2iZ5xTM-2e2ngib-yED9yE-8ehkvX-x731pk-bARqzj-24w3DCP-oZ4DHt-qH5xcY-rtxsoo-2ja5UxU-r8CtzW-rnvvu7-2jKfqdD-qHhGDZ-rDY7mf-rE57ZR-2hqGwmJ-rnBTiK-regLXs-rE4MQP-rnti8L-rDXhDF-rBMs63-rnBhwa-d2kZGh-rDYic3-rDX9X8-2iKoRCJ-4KpQeR-rnuHmf-rBLQWf-rnvFn3-rnB3vV-rnupk3-rkKtie-rkJuA6-rkJNBr-qH58gm-qHhKir-qH4bJA-qHhz3r.
McMillan, S. (2007). Sea Otter (Enhydra lutris) with Pup in Morro Bay, Ca 2017. Flickr. Retrieved December 18, 2022, from https://www.flickr.com/photos/sammcmillanjr/39311426631/in/photolist-22TPkxM-EefJiD-2au7kXU-tsQ7pQ-25av1G6-Tnmj4c-2655qrF-8dXNnK-EnuMug-4NJSaT-2nAz6PQ-8e253J-Ly5XMW-8ehkvX-ZjQQ4g-LaQnR3-i4pkmw-4gNLTi-2iZ5xTM-7wTEaL-4NJRQc-oN8zP3-2kXEJFT-7xpgJH-4NP6uu-9cMz74-4qqmfF-4j9PUE-47Sf9s-d2CE8Y-d2CBPQ-tsQ5A9-47Natp-6ojdgE-2i3to7S-2i3to9v-A8355d-d39HV5-cJYFDw-d39JSN-d39JQ1-d2CD3q-d2CDPE-d2CDL9-d2CCPE-d2CC1S-2i3snER-2i3snzR-d39Jab-d2CDYC.
Reding, A. (2011). Sea otter sex. Flickr. Retrieved December 18, 2022, from https://www.flickr.com/photos/seaotter/16428900798/in/photolist-39E2vP-febunj-2jNtABa-8rwbwb-4oFj3s-r2LpQj-wNSJDw-x4r1C3-wMxrrn-x731pk-kXyChB-xeebdU-wMp1S9-bwvub-orACoy-wYzYhL-wM4T6p-wxte9D-tAtdQN-wYKpV1-ovNLE3-ou6bfS-tjaTbo-q2HiS5-wxiWYb-pJyJ3N-pYNmHN-pYNnbm-ow5yQQ-tnNZ1u-wwy3sA-owcmyj.