Abstract or Keywords
A senior thesis in Marine Science.
Humpback whales (Megaptera novaeangliae) travel seasonally from polar arctic waters to feed in the summer to tropical equatorial waters to breed during the winter. However, little is known about M. novaeangliae winter activities, particularly in regard to breeding, and how those communal activities contribute ecologically and to anthropogenic interactions. In this work, humpback individuals were studied using Customized Animal Tracking Solutions (CATS) tagging methodology during winter months of 2021 and 2022 off the coast of west Maui, Hawaii. The ethogram coding software Behavioral Observation Research Interactive Software (BORIS) was utilized to quantify behaviors captured in footage from CATS tag synchronized video and audio data (n = 20). Footage from humpback whales was reviewed and coded with ethogram guidelines, with the final ethogram product accommodating swimming behaviors, camera angle, Activity Level (on a scale of 1 to 4), presence of conspecific individuals in camera view (accompanied or unaccompanied), singing (travel or stationary), social sounds (focal, non-focal, or undetermined), interactions with mackerel scad, locally known as opelu (Naso hexacanthus), and various other behaviors. This study’s analysis focused on a subset of these behaviors, looking at daily trends in Activity Level, surfacing, and surface activity. Preliminary results suggest correlations between energy expenditure levels and the time of day, with a predominant resting period during afternoon hours. Understanding daily resting patterns may provide critical information for stakeholders in the management of limits on vessel-whale interactions during crucial periods of singing-based communication. Other future data analysis would evaluate how Activity Level varied with presence or absence of other humpback individuals, pod behaviors, and factors influencing seafloor interactions.