The feeding habits of humpback whales developed through behavioral changes over time in response to limited food resources
(National Wildlife Foundation, n.d. )
Baleen whales, collectively known as mysticetes, evolved and adapted in response to the lack of food available and the increase of competition for food. Their unique jaw came to evolve to accommodate the filter feeding method, as did their gigantism. As prey became condensed but patchier it resulted in intense nutrient upwellings. This led to binge feeding that allowed the humpback to grow and be bulky enough to travel far to new patched, encouraging the whales to migrate to find the best food source (Gabriele et al., 2017). The feeding influenced their head shape, growth rates, and migratory habits. As time went on, this evolution encouraged adaptation of feeding methods to maximize the most amount of net energy from feeding, resulting in the lunge method and bubble nets. (Odd Animal Specimens, 2022)
As a baleen whale, the way they feed is an adaptation that has defined their physiology, and as a humpback whale their feeding behavior defines their unique social culture. These behaviors have been taught and passed down!
(NOAA Fisheries, n.d.)
Initially the young humpback whales nurse from their mothers' milk, and observe the mothers' feeding habits. They are first taught foraging through being guided by other whales even before they are ready to eat solid foods. There is little known about how they truly learn their feeding habits other than observation, although it is hypothesized that bubble nets are additionally learned through playing with bubbles. (OctoberCMS, n.d.)
(OctoberCMS, n.d.)
Adults quickly develop intricate forms of feeding to increase the benefit while mitigating the cost. Individual feeding involves foraging, where the methods are termed as lunge feeding and bottom feeding. Lunge feeding is the process where the whale comes from underneath the prey, quickly accelerates, and opens its mouth (up to 90 degrees) to swallow tons of water and food. Bottom feeding is a similar method of scooping the sediment and crustaceans to which large plumes of mud will rise to the surface. In both methods the baleen plates filter the prey. (McMillin et al., 2019)
(NMSF, 2020)
Humpback whales often travel and groups and participate in filter feeding near one another. It is theorized that foraging and playing with one another is what led to the bubble net feeding developing. This behavior can be individual but is most commonly done in groups. This method is when a stream of bubbles is released around the prey in a circle that is slowing closing in in order to feed easier. This can be done in groups up to 4, but is most commonly done with 2. (Garland et al., 2022)