Full Description

"Jumping was found to vary seasonally, with number of jumps every 0.5 h much higher in June than during other months in which observations were made (April, May, August, and September in 2000 and 2001). Over 1000 jumps per day were recorded in a short (0.8 km) stretch (at river kilometer 61) of the Suwannee River in northwestern Florida. Jumping activity peaked near dawn and to a lesser degree near sunset in months other than June."

"Sonograms of sturgeon jumping sounds were compared and found to be distinct and different from sounds of other fish jumping or from objects dropped into the water for comparative purposes."

"Jumping sturgeon produce loud, distinctive sounds that travel long distances in air, and probably even farther in water. An eloquent early description of Atlantic sturgeon jumping by Catesby (1731) possibly provides a clue: ‘… in May, June and July, the rivers abound with them, at which time it is surprising, though very common to see such large fish elated in the air, by their leaping some yards out of the water; this they do in an erect posture, and fall on their sides, which repeated percussions are loudly heard for some miles distance…"

"The rate of jumping between early/mid June (Fig. 1, closed circles) was very different from other months (Fig. 1, open circles) where the jumping rate was much lower (<250 jumps per day) and characterized by peaks near dawn and sunset. The June jumping rate was much greater (up to 47 jumps per 0.5 h, 1057 jumps per day) and decreased during midday (5–16 jumps per 0.5 h). During night hours (mean _ 30 jumps per 0.5 h, 22:00–05:00) the jumping rate was also very high. June nighttime jumping rate and pattern, based on limited data for three nights, was similar on full-moon and dark nights. Sturgeon jumping sounds (analyzed as sonograms) had a distinct, typical pattern (Fig. 2) consisting of: (i) pre-jumping (up to 2–3 s prior to exit) sounds that were present in many but not all sonograms, possibly due to tail beats as the fish accelerated toward the surface; (ii) short, sharp, exit sounds made as the fish first broke the water surface; (iii) additional exit sounds occurring if and when the caudal fin slapped the water surface as the fish was about to clear the water; (iv) a period of little or no sound while the fish was completely airborne for 1–2 s (depending on height of jump and typically 1.2–1.5 s); (v) a sharp, loud report caused by the impact and reentry of the fish (typically on its side, back, or at an oblique angle); (vi) continued (typically 1.5 s) but declining sounds associated with primary splash; (vii) secondary splashes of water after the fish had re-entered the water; (viii) cessation of sound associated with subsidence of all splashing; (ix) possible post-subsidence sounds occurring soon (<2 s) or considerably after (up to 4 s) subsidence. The characteristic sonogram patterns were sometimes discernable for fish jumping at distances of up to about 300 m."

Observation Environment Quotes

"The study site was located at river kilometer 61 (upstream from the river mouth) in the Suwannee River in northwestern Florida, USA. Based on previously observed jumping and on past success in collecting sturgeons with drift nets at the site, this site is one of the most intensely utilized sturgeon holding areas in the river."

Sound Name Quotes

"Sturgeon jumping sounds (analyzed as sonograms) had a distinct, typical pattern (Fig. 2) consisting of: (i) pre-jumping (up to 2–3 s prior to exit) sounds that were present in many but not all sonograms, possibly due to tail beats as the fish accelerated toward the surface; (ii) short, sharp, exit sounds made as the fish first broke the water surface; (iii) additional exit sounds occurring if and when the caudal fin slapped the water surface as the fish was about to clear the water; (iv) a period of little or no sound while the fish was completely airborne for 1–2 s (depending on height of jump and typically 1.2–1.5 s); (v) a sharp, loud report caused by the impact and reentry of the fish (typically on its side, back, or at an oblique angle); (vi) continued (typically 1.5 s) but declining sounds associated with primary splash; (vii) secondary splashes of water after the fish had re-entered the water; (viii) cessation of sound associated with subsidence of all splashing; (ix) possible post-subsidence sounds occurring soon (<2 s) or considerably after (up to 4 s) subsidence. The characteristic sonogram patterns were sometimes discernable for fish jumping at distances of up to about 300 m."