Optimizing automated photo identification for population assessments.

Several legal acts mandate that management agencies regularly assess biological populations. For species with distinct markings, these assessments can be conducted noninvasively via capture-recapture and photographic identification (photo-ID), which involves processing considerable quantities of photographic data. To ease this burden, agencies increasingly rely on automated identification (ID) algorithms.

Maternal investment, body condition and calf growth in humpback whales.

Given recent declines in North Pacific humpback whale (Megaptera novaeangliae) reproductive output and calf survival, there is additional urgency to better understand how mother-calf pairs allocate energy resources across their migratory cycle. Here, unoccupied aerial system (UAS; or drone) photogrammetry was used to quantify the body size and condition (BC) of humpback whales on their Hawai'i (HI) breeding and Southeast Alaska (SEAK) feeding grounds. Between 2018 and 2022, we collected 2410 measurements of 1659 individuals.

Energetic cost of gestation and prenatal growth in humpback whales.

Improving our understanding of energy allocation in reproduction is key for accurately parameterizing bioenergetic models to assess population responses to environmental perturbations and anthropogenic disturbance. We quantified the energetic cost of gestation in humpback whales (Megaptera novaeangliae) using historical whaling records, non-invasive unoccupied aerial system (UAS) photogrammetry and post mortem tissue samples. First, we estimated relative birth size using body length measurements of 678 mother-fetus pairs from historical whaling records and 987 mother-calf pairs measured in situ using UAS-photogrammetry.

Solitary humpback whales manufacture bubble-nets as tools to increase prey intake.

Several animal species use tools for foraging; however, very few manufacture and/or modify those tools. Humpback whales, which manufacture bubble-net tools while foraging, are among these rare species. Using animal-borne tag and unoccupied aerial system technologies, we examine bubble-nets manufactured by solitary humpback whales () in Southeast Alaska while feeding on krill.

Quantifying the abundance and survival rates of island-associated spinner dolphins using a multi-state open robust design model.

Spinner dolphins (Stenella longirostris subsp.) occupy the nearshore waters of several Hawaiian Islands. Due to their constrained behavioral pattern and genetic isolation, they are vulnerable to anthropogenic threats.