The fish approach the water surface at high speed (about 10 m/s in large fish; 20-30 body lengths/s) with their lateral fins furled against the body. They get accelerated by beating their tails rapidly, and break through the water surface at a shallow angle to the horizontal. Four fish in ray-finned fish family (Beloniformes) and salmon have this jumping behavior. The ray-finned fish includes needlefish,Lauritzen, D. V., F. Hertel, and M. S. Gordon. 2005. "A Kinematic Examination of Wild Sockeye Salmon Jumping up Natural Waterfalls." Journal of Fish Biology 67 (4): 1010–20. doi:10.1111/j.0022-1112.2005.00799.x flyingfish,Davenport, John. 1994. "How and Why Do Flying Fish Fly?" Reviews in Fish Biology and Fisheries 4 (2): 184–214. doi:10.1007/BF00044128 halfbeak, and sauries. Salmon jump out waterfalls during upstream spawning migrations.
