The innovation and diffusion of novel foraging strategies within a population can increase the capacity of individuals to respond to shifts in prey abundance and distribution. Since 2011, some humpback whales (Megaptera novaeangliae) off northeastern Vancouver Island (NEVI), Canada, have been documented using a new feeding strategy called "trap-feeding." We provide the first description of this foraging innovation and explore the ecological and social variables associated with its diffusion using sightings data, video analysis, and logistic regression modeling. The number of humpback whales confirmed to trap-feed off NEVI increased from two in 2011 to 16 in 2015. Neither the locations of trap-feeding sessions nor prey species consumed differed from those documented during lunge-feeding. However, preliminary results indicate that the schools of fish consumed when individuals trap-fed were smaller and more diffuse than those consumed when whales lunge-fed. Top-ranked models predicting whether an individual would be observed exhibiting trap-feeding behavior included the following parameters: average number of days per year that the individual was seen off NEVI and proportion of the individual's associations that were with other trap-feeders. These results suggest that trap-feeding may be a culturally transmitted foraging innovation that provides an energetically efficient method of feeding on small, diffuse prey patches.

Predators exert strong effects on ecological communities, particularly when they re‐occupy areas after decades of extirpation. Within species, such effects can vary over time and by sex and cascade across trophic levels. We used a space‐for‐time substitution to make foraging observations of sea otters (Enhydra lutris) across a gradient of reoccupation time (1–30 years), and nonmetric multidimensional scaling (nMDS) analysis to ask whether (a) sea otter niche space varies as a function of occupation time and (b) whether niche space varies by sex. We found that niche space varied among areas of different occupation times. Dietary niches at short occupation times were dominated by urchins (Mesocentrotus and Strongylocentrotus spp; >60% of diets) in open habitats at 10–40 m depths. At longer occupation times, niches were dominated by small clams (Veneroida; >30% diet), mussels (Mytilus spp; >20% diet), and crab (Decapoda; >10% diet) in shallow (<10 m) kelp habitats. Diet diversity was lowest (H′ = 1.46) but energy rich (~37 kcal/min) at the earliest occupied area and highest, but energy poor (H′ = 2.63, ~9 kcal/min) at the longest occupied area. A similar transition occurred through time at a recently occupied area. We found that niche space also differed between sexes, with bachelor males consuming large clams (>60%), and urchins (~25%) from deep waters (>40 m), and females and territorial males consuming smaller, varied prey from shallow waters (<10 m). Bachelor male diets were less diverse (H′ = 2.21) but more energy rich (~27 kcal/min) than territorial males (H′ = 2.54, ~13 kcal/min) and females (H′ = 2.74, ~11 kcal/min). Given recovering predators require adequate food and space, and the ecological interactions they elicit, we emphasize the importance of investigating niche space over the duration of recovery and considering sex‐based differences in these interactions.

We present an ocean-basin-scale dataset that includes tail fluke photographic identification (photo-ID) and encounter data for most living individual humpback whales (Megaptera novaeangliae) in the North Pacific Ocean. The dataset was built through a broad collaboration combining 39 separate curated photo-ID catalogs, supplemented with community science data. Data from throughout the North Pacific were aggregated into 13 regions, including six breeding regions, six feeding regions, and one migratory corridor. All images were compared with minimal pre-processing using a recently developed image recognition algorithm based on machine learning through artificial intelligence; this system is capable of rapidly detecting matches between individuals with an estimated 97–99% accuracy. For the 2001–2021 study period, a total of 27,956 unique individuals were documented in 157,350 encounters. Each individual was encountered, on average, in 5.6 sampling periods (i.e., breeding and feeding seasons), with an annual average of 87% of whales encountered in more than one season. The combined dataset and image recognition tool represents a living and accessible resource for collaborative, basin-wide studies of a keystone marine mammal in a time of rapid ecological change.

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In the eastern North Pacific Ocean, common minke whales (Balaenoptera acutorostrata) are widespread but encountered relatively infrequently. It is generally believed that they make annual migrations between higher latitudes in the summer and lower latitudes in the winter; however, in some temperate coastal regions where common minke whales have been sighted year-round they have been referred to as resident. To determine movement patterns of common minke whales found in coastal waters of British Columbia and Washington we examined photo-identification data that were collected opportunistically from 2005–12. These data were from four non-overlapping areas between 48°N and 53°N. Despite year-round search efforts, common minke whales were only encountered between April and October. Most of the 44 unique individuals identified in 405 encounters displayed fidelity to areas both within and among years. Five of these whales made relatively large-scale intra-annual movements between areas on six occasions. They were documented to move up to 424km in a northerly direction in spring and up to 398km in a southerly direction in autumn. The seasonal patterns of these movements provide new insights into the foraging ranges and migrations of the individuals. Ecological markers provide evidence that the common minke whales photographed undertake annual long distance migrations. Scars believed to be from cookiecutter shark (Isistius brasiliensis) bites were observed on 43 individuals and the majority of whales documented with good quality images each year had acquired new scars since the previous year. Furthermore, the commensal barnacle Xenobalanus globicipitis was observed on three individuals. Since these sharks and barnacles are from relatively warm waters, it can be inferred that they interacted with the common minke whales at lower latitudes. These findings may have important implications for the definition and management of common minke whale stocks and/or populations in the eastern North Pacific.

From June to August 2012, we conducted over 500 h of visual surveys from Cormorant Island, British Columbia, to determine behaviour and habitat use patterns of nearby cetaceans. Seven species were documented, but Minke Whales (Balaenoptera acutorostrata) were by far the most common and were observed lunge feeding at the surface on 15 occasions. In addition, this species was documented surface lunge feeding on Pacific Herring (Clupea pallasi) and Pacific Sand Lance (Ammodytes personatus) on 32 occasions during vessel-based cetacean surveys around Cormorant Island between 2010 and 2014. Although Minke Whales are relatively uncommon in British Columbia, these results indicate that they can regularly be found in specific feeding areas during the summer.