A Note on Suckling Behavior and Laterality in Nursing Humpback Whale Calves from Underwater Observations

We investigated nursing behavior on the Hawaiian breeding grounds for first year humpback whale (Megaptera novaeangliae) calves. We observed and video-documented underwater events with nursing behavior from five different whale groups. The observed nursing events include behaviors where a calf posit...

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Bibliographic Details
Published in:Animals
Main Authors: Ann M. Zoidis, Kate S. Lomac-MacNair
Format: Article in Journal/Newspaper
Language:English
Published: MDPI AG 2017
Subjects:
Online Access:https://doi.org/10.3390/ani7070051
https://doaj.org/article/6f1dd4d40954473aaab3ba9fe271e2b9
Description
Summary:We investigated nursing behavior on the Hawaiian breeding grounds for first year humpback whale (Megaptera novaeangliae) calves. We observed and video-documented underwater events with nursing behavior from five different whale groups. The observed nursing events include behaviors where a calf positions itself at a 30–45° angle to the midline of the mother’s body, with its mouth touching her mammary slit (i.e., suckling position). On two occasions, milk in the water column was recorded in close proximity to a mother/calf pair, and on one occasion, milk was recorded 2.5 min after suckling observed. Nursing events, where the calf was located in the suckling position, were found to be short in duration with a mean of 30.6 s (range 15.0–55.0, standard deviation (SD) = 16.9). All observations of the calf in the suckling position (n = 5, 100%) were with the calf located on the right side of the mother, suggesting a potential for right side laterality preference in the context of nursing behavior. Our study provides insight into mother/calf behaviors from a unique underwater vantage. Results supplement previous accounts of humpback whale nursing in Hawaiian waters, validate mother/calf positioning, document milk in the water column, and introduce the potential for laterality in nursing behavior for humpback whale calves.