The impact of the experimental introduction of a bycatch reduction device for juvenile fish in the shrimp trawl fishery in the Colombian Caribbean was assessed for invertebrates. Four net configurations were compared: no device, turtle excluding device alone, bycatch reduction device for juvenile fish alone and both devices incorporated on the net. This last configuration resulted in the lowest invertebrate mean CPUE but the turtle excluding device also performed well. Response in CPUE and mean size of selected invertebrate taxonomic categories to the device configurations was distinctive but disparate. The thesis is advanced that full report of invertebrates should be made in any study on bycatch even though bycatch reducing devices rarely have invertebrates in focus.