bubble-net
n.— «A light wind blew in from the ocean, and the skipper had stopped his boat to watch three 30-ton humpback whales lunging from the waves or circling to make so-called bubble-nets in which they like to catch clouds of small fish.» —“In British Columbia, Where the Sun Set on an Empire” by Simon Winchester New York Times Oct. 19, 2007. (source: Double-Tongued Dictionary)