The Food and Feeding Habits of the Kumu, Parupeneus porphyreus

Abstract

The kumu, Parupeneus porphyreus, is one of the most valuable reef fishes in Hawaii. It is a member of the goatfish family (Mullidae) and is endemic to Hawaii. One hundred and ninety-eight specimens, ranging in size from 31 to 306 mm, were collected from four areas around Oahu, Hawaii. Collections were made from July through November, 1968. The anatomy and the contents of the digestive systems were examined The digestive system is short. The stomach is V-shaped with a bulbiform pylorus. There are 20 pyloric caeca. The instestine has one siphonal loop. Transforming specimens differ in having a shorter, straight intestine. They also have sharper pharangeal teeth and longer gill rakers than do the adults. Occurrence of food in the entirA gastrointestinal tract was used in ranking relative fullness. These rankings, compared with time of capture, indicated feeding was nocturnal or crepuscular among larger fish (only very young kumu fed during the day) and that food passed through the alimentary canal within 19 hours. Twenty-three food items were identified; 12 of them occurred in >10% of the guts. Crabs were the most important food, followed by other crustaceans (copepods, isopods, other decapods) and other invertebrates. Sand occurred in 57% of the specimens. An extensive comparison of food items vs. fish size demonstrated various relationships. Although crabs were eaten by nearly all fish, only large kumu ate Stenopus and other fish, and only small kumu ate copepods and isopods.