Bubbles Corral Prey

aerial photograph of whale catching prey in blue water

Biological Strategy

Humpback whale

AskNature Team

Image: Christin Khan/NOAA / Wikimedia Commons / Public Domain - No restrictions

Cooperate Within the Same Species

A species is a group of organisms capable of breeding to produce fertile offspring. When individuals within a species undertake activities that benefit one another, that cooperation benefits not just the individuals, but also local and wider populations of that species. Collaborating in activities such as finding food, controlling parasites, and protecting from predators enhances overall survival. To cooperate, there must be enough benefit to an individual, and especially to a population, to justify any risk taken by individuals. Through cooperation, risk is distributed among individuals and the benefits to the community are greater than the sum of the benefits to individuals. An example is birds that gather in flocks, a cooperative activity more beneficial than acting alone. While some birds forage, others watch for predators. When one finds food, others also feed on it. Despite potential short-term competition for an individual that finds food, over the long-term, that same individual benefits when others find different food sources.

Search this Function

Capture, Absorb, or Filter Organisms

Many living systems must secure organisms for food. But just as one living system must capture its prey to survive, its prey must escape to survive. This results in capture and avoidance strategies that include trickery, speed, poisons, constructed traps, and more. For example, a carnivorous plant called the pitcher plant has leaves formed into a tube that collect water. Long, slippery hairs within the tube face downward. When insects enter the tube seeking nectar, they lose their footing and slide inside, unable to climb out and escape being eaten and digested by the plant.

Search this Function

Mammals

Class Mammalia (“breast”): Bats, cats, whales, horses, humans

Mammals make up less than 1% of all animals on earth, but they include some of the most well-known species. We know first-hand some of the characteristics that make mammals unique, like having hair, being able to sweat, and producing milk through mammary glands. Another critical shared feature is a set of highly-specialized teeth. Unlike sharks or alligators, for example, whose teeth are generally all the same size and shape, mammals have differently shaped teeth in different areas of the jaws to target specific foods or foraging strategies.

Search this Living System

Humpback whales control movement of prey by blowing spiraling nets of bubbles underwater.

“Behaviourally, humpback whales capture prey by engaging in complex feeding manoeuvres that are often accompanied by the apparently directed use of air bubbles. The ability of bubble barriers to corral or herd fish has been reported by a number of authors (e.g., Smith, 1961; Blaxter & Batty, 1985; Sharpe & Dill, 1997). Bubble use by humpback whales has been observed in many of their feeding habitats and is reported to occur in a variety of configurations. These bubble-feeding behaviours appear to vary in nature among both individuals and regions; for example, bubble clouds (the production of a single or multiple bursts of seltzer-sized bubbles) are commonly observed from humpback whales in the Gulf of Maine, but never in Alaskan waters.

“Of the various bubble configurations reported, the most complex appears to be the bubble net (Jurasz & Jurasz, 1978; Watkins & Schevill, 1979; Hain et al., 1982). Existing descriptions of this unique and complex behavior are currently derived only from surface observations, predominately Jurasz & Jurasz (1979) and Hain et al. (1982). As described by Jurasz & Jurasz (1979), bubble nets are rings of distinctive bubbles that appear at the surface in a closed circle or figure ‘9’. In the Gulf of Maine, bubble nets have been further described by Hain et al. (1982) as a ring formed by a series of discrete bubble columns, blown at 3–5 m depth, by a whale that is rotated inward with the flippers in a vertical plane. The nets were described as incorporating 1.25–2 revolutions with smaller bubbles grading into larger bubbles as the net was closed. In both descriptions, whales fed in the centre of the completed bubble net at or near the surface. (Wiley et al. 2011: 576-577)

Last Updated September 14, 2020

References

Journal article

Underwater components of humpback whale bubble-net feeding behaviour

Behaviour | 20/06/2011 | David Wiley, Ari Friedlaender, Mason Weinrich, Alessandro Bocconcelli, Danielle Cholewiak, Michael Thompson, Colin Ware

embedly preview

Reference

Journal article

AskNature