Historically, North American river otters (Lontra canadensis) were widely dispersed throughout the North American continent. Trapping pressures and urbanization have led to regional exclusion of North American river otter populations from historic habitats, leading the Association of Zoos and Aquariums to spearhead conservation and captive breeding efforts to maintain genetic diversity of the aquatic mustelid. Difficulties in consistently breeding captive North American river otters have spotlighted a need to understand how geography and life history of adult individuals influence reproductive events. This study analyzed the AZA studbook records for all litters born in captivity from 2008 to 2014 (N = 47) to assess whether any correlations existed between historical data and timing of parturition events. ANOVA tests found significant differences in mean parturition date between litters by dam origin region (F = 6.09, p-value = 0.018) and by parturition location (F = 12.73, p-value = 0.001). A Mann-Whitney u test found a difference (p-value = 0.0365) between median parturition dates of litters born in the north and those born in the south regions. PCA testing showed that the data form independent groups by both dam and sire origin latitudes, confirming the existence of a significant relationship between latitude and the timing of reproductive events. However, this study did not conclusively determine which latitude (the origin of the dam, origin of the sire, or latitude at the time of breeding) has the most influence on reproductive events among the captive North American river otter population. Future work should strive to identify other variables related to physiological condition and/or genetic variation between North American river otter subspecies. These factors may lead to more discreet groups and will likely aid in the development of a predictive model of parturition timing among the captive population using known life history data.

Library of Congress Subject Headings

North American river otter--Parturition; Latitude

Publication Date


Document Type


Student Type


Degree Name

Environmental Science (MS)

Department, Program, or Center

Thomas H. Gosnell School of Life Sciences (COS)


Larry Buckley

Advisor/Committee Member

Susan Smith Pagano

Advisor/Committee Member

David Hamilton


Physical copy available from RIT's Wallace Library at QL737.C25 B34 2016


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