The catching efficiency of light traps and morphology of the native species from Barito river, Indonesia

Abstract

Various fishing gears are being used for harvesting fish and shrimp in Barito River, Indonesia. However, the use of lighted traps is still poorly studied. A set of fishing gears associated with light emitting diode (LED) and incandescent lamps was used as sampling tools. The trials consisted of 113-trap hauls/lamp type using 1-night submersion time of 15 h. The light traps were standardized to a catch per unit effort (CPUE). The light traps sampling accounted for 397 specimens assigned to 11 species of 7 families. There was highly significant difference in the number of catches between shrimp and fish (P<0.001). Shrimp sizes ranged of 24–85 mm total length and 0.3–10 g weight, while for fish 27–310 mm and 0.4–101 g. Yellow and red LED light traps seemed to be effective in catching Macrobrachium rosenbergii as well as white LED ones for Oxyeleotris marmorata. Both species solely showed positive allometric growth type (b = 3.42 and 3.28), while other species displayed negative allometric growth pattern (b = 0.82–2.71) with the condition factor (K) values ranged of 0.36–1.56. A new native species Macrobrachium sp. were found and considered as multichromatic species. The size and shape of the light traps did not affect number of catch. The mean CPUEs for incandescent and LED light traps were 0.07±0.06 and 0.13±0.20 fish net-1 night-1. No significant difference in the relative catching efficiency between both light trap types was observed.