PDF] Comparison of Plankton Net and Light Trap Methodologies for Sampling Larval and Juvenile Fishes at Offshore Petroleum Platforms and a Coastal Jetty off Louisiana

Comparisons of fish collected in nets versus light traps indicated that light traps generally overlapped the net's smaller sizes, while collecting significantly larger individuals, whereas at the jetty, greater overlap in gear size distributions were observed. We sampled ichthyoplankton at artificial structures across the continental shelf (3- 219-m depth) of the northern Gulf of Mexico and compared passive plankton net and light trap methodologies at three offshore petroleum platforms (shelf slope, mid-shelf, and inner shelf ) and plankton push-net and light trap methodologies at a coastal jetty. Clupeiform fishes dominated collections for all gears (59-97% of the total catch). Plankton nets collected more fish than light traps at two platforms (plankton net versus light trap, minus clupeiforms: 1,404 versus 659 at slope; 3,076 versus 12,474 at mid-shelf; and 1,689 versus 1,193 at inner shelf ), and jetty push nets collected more fish than light traps (33,147 versus 849). Nets collected more families than light traps at the shelf slope and mid-shelf platforms (plankton net versus light trap: 43 versus 35; 38 versus 35; and 32 versus 32) but only collected more taxa (genus level) than light traps at the shelf slope platform (plankton net versus light trap: 56 versus 47; 75 versus 78; and 50 versus 56). Jetty push nets collected more families (39 versus 19) and taxa (77 versus 34) than light traps. Kolmogorov-Smirnov length-frequency comparisons of fish collected in nets versus light traps indicated that light traps generally overlapped the net's smaller sizes, while collecting significantly larger individuals. At the jetty, greater overlap in gear size distributions were observed. There was low taxonomic similarity between gears at the two deeper platforms (Schoener's Similarity Index values = 0.32-0.38) but higher similarity (0.63) at the inner shelf platform, which was most dominated by clupeiforms. At the jetty, push-net and light trap samples had relatively high taxonomic similarity (0.61). Few significant differ- ences were detected between Shannon-Weiner Diversity Indices for platform light trap and net samples, while jetty push nets had significantly higher diversity than light traps. When signifi- cant differences in mean total densities and mean total CPUEs were found between new versus full moon phases, four out of five instances had greater new moon catches.

PDF) An introduction of light traps for sampling freshwater shrimp

An assessment of the larval fish diversity within a coastal marine

PDF] Comparison of Plankton Net and Light Trap Methodologies for

GUIDING THE PATH OF LARVAE: THE POTENTIAL OF LIGHT TRAPS IN

PDF) Comparison of Light Traps and Plankton Tows for Sampling

Symbiotic copepods (Cyclopoida and Siphonostomatoida) collected by

Symbiotic copepods (Cyclopoida and Siphonostomatoida) collected by

PDF) Importance of the artificial light field around offshore

Analysis of three sampling methods of early life history of fish