Thresher sharks have an inferior mouth type and their typical prey are small to medium sized schooling fish, cephalopods and sometimes seabirds. Their main hunting strategy is to use their whip-like tail in order to stun fish that they can then go retrieve (Knaub et al. 2024).
Threshers can use their tail to whip over their heads as well as to the sides of their bodies. Their typical hunting form is broken into four phases: preparation, strike, wind down recovery, and prey collection. Essentially threshers speed up towards their prey (preparation) before lowering their snout and abducting their pectoral fins to slow themselves down as they raise their caudal fin (strike). In this motion they act akin to a trebuchet throwing an object from a sling. The apex of the strike happens as the caudal fin aligns over the dorsal fin and is so powerful it can diffuse gas out of the water (Knaub et al. 2024).
A sideways strike is only used after a successful overhead strike. The average tail speed of one of these whips is 14.03m/s or 31.38 miles per hour. The fastest ever recorded tail whip clocked in at 21.8m/s or 48.77 miles per hour (Knaub et al 2024).
I was unable to find information on sensory biology in Alopias vulpinus although it is thought that their eyesight is poor like many other shark species. Due to this it is likely that they rely on their Ampullae of Lorenzini and lateral line in order to determine what their surroundings are like. It is thought that part of the daily migration of threshers is in order for them to be below their prey which may suggest that they use shadows to determine light intensity and rough shapes for hunting (Cartamil et al. 2010).
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