Effect of predator exposure on the performance and survival of red drum (Sciaenops ocellatus)

• Main Authors: Jessica L. Beck, Jay R. Rooker
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2010
• Subjects: Red drum; Sciaenops ocellatus
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.658.9080; http://www.tamug.edu/rooker/pdf/Beck+2012.pdf?origin%3Dpublication_detail

Abstract The influence of predator exposure on the survival of hatchery red drum, Sciaenops ocellatus was investigated under laboratory conditions. Several prey-capture (attack distance, mean attack velocity, capture time, and gape cycle duration) and anti-predator (reaction distance, response distance, mean velocity, and maximum velocity) performance varia-bles were quantified using high-speed video for juvenile red drum (25–30 mm standard length, LS) reared with and without predators (pinfish, Lagodon rhomboides). Univariate contrasts of prey-capture events demonstrated that attack distance (mean ± s.e.) was significantly greater in red drum reared with (1.20±0.16 mm) versus without (0.65±0.09 mm) pinfish predators. During anti-predator events, red drum reared with predators had approximately 300 % greater reaction distance and 20%–30% greater response distance, mean velocity and maximum velocity versus fish reared without predators; however, these differences were not statistically signif-icant. Following video assessments, a series of mortality experiments were conducted using free-ranging pinfish predators. Mortality rates (Z) ranged from 0.047 to 0.060 (Z/hr/predator) and did not differ significantly among treatments.