Survival of Amputated Striped Corvina Cynoscion reticulatus (Pisces: Sciaenidae) off the Southeast Coast of the Gulf of California

Abstract

Abstract Records of amputated teleost fish in the aquatic environment are becoming more frequent; however, it is difficult to find the causes of amputation when there is little evidence. For this reason, this study focused on describing the damage and causes of the amputations of two striped corvina Cynoscion reticulatus specimens collected from landing sites of a small-scale fishery in northwestern Mexico, and determining if the damaged organisms could survive in the environment. Specimens were sexed and whole-body radiographs of amputated specimens and of a normal specimen were taken. Morphometric measurements (TL, SL, MDF, BD, HL, and TW) of the amputees and of 54 normal specimens were recorded. The TL of amputees was estimated and compared to that of normal specimens; stomach contents were also analyzed. The first organism was male, it was missing 1 ½ vertebra and had an estimated TL of 36.64 cm; the second was a female, it was missing 3 ½ vertebrae, with an estimated TL of 38.59 cm; both had bite marks, skin regeneration, and scales in the affected area. Stomach analysis showed Engraulidae fish of the Anchoa genus in stomach contents. There were no significant differences in the measurements of the two amputated and 54 normal organisms (p>0.05). Based on this evidence, it was determined that amputated fish could survive, escape from predators, feed, and obtain energy to heal wounds; the amputations were attributed to the bottlenose dolphin Tursiops truncatus, a potential predator of croakers in the study area and other regions.

Keywords

• injuries
• tailless
• healing
• predator bite
• small-scale fishery