Whale shark (Rhincodon typus) predatory flexible feeding behaviors on schooling fish

Abstract

Whale sharks are known to feed primarily on zooplankton all over the world; however, recent findings suggest that they also prey on fish using behaviors that have not been fully described. Here, we provide detailed evidence of whale sharks interacting with schools of anchovy on four occasions in Bahia de Los Angeles, Baja California, Mexico. Three of these were predatory interactions in multi-species feeding frenzies, and one was a non-predatory interaction. In predatory interactions, whale sharks exhibited two types of feeding behaviors: (1) stationary suction-feeding, a previously described behavior for whale sharks, and (2) lunge-feeding, which has not been previously described in whale sharks, but has been observed among other large filter feeders, such as rorqual whales. The whale sharks moved simultaneously around the school of anchovy, lunging simultaneously or one after another into the school, with 66% (N = 17) of these lunges occurring in the same direction. In the non-predatory interaction, whale sharks exhibited "sit-and-wait" behavior. The evidence presented here, along with previous observations, suggests that whale sharks may change their feeding strategy from suction to lunge-feeding when other predators corner schooling fish.

Return of large fin whale feeding aggregations to historical whaling grounds in the Southern Ocean

“…Behavioural observations. The behaviour in aggregations was dominated by feeding, with animals lunging with mouths agape, tight turning and repeated strong vertical diving, resembling a 'feeding frenzy' [37][38][39] . Surfacing animals displayed expanded buccal cavities (Fig.…”

Parasitic Copepods as Biochemical Tracers of Foraging Patterns and Dietary Shifts in Whale Sharks (Rhincodon typus Smith, 1828)

“…To improve feeding efficiency and increase growth rates, juvenile whale sharks (mostly males) gather at coastal aggregation sites to take advantage of ephemeral bursts of productivity [5]. Whale sharks feed on a wide range of zooplankton, including krill [6], copepods [7], crab and fish larvae [8][9][10], and small nektonic fishes, such as anchovy [11][12][13]. More recently, biochemical analyses suggest that these are not the only items that these animals consume and that food sources can also include significant amounts of floating algal material [14,15].…”