Regional Differences in Otolith Morphology of the Deep Slope Red Snapper Etelis carbunculus

M. Kimberly Smith
1992 Canadian Journal of Fisheries and Aquatic Sciences  
Smith, M. K. 1992. Regional differences in otolith morphology of the deep slope red snapper Etelis carbunculus. Sagittal otoliths from four populations of the Pacific deep slope red snapper Etelis carbunculus Cuvier were compared using Fourier descriptors and other shape indices, linear proportions, and dry weight. Otoliths from Hawaii, Vanuatu, Fiji and French Polynesia and a small number from the Commonwealth of the Northern Marianas Islands (NMI) were examined. Regional shape and weight
more » ... ape and weight characteristics were distinguishable, despite the wide range of individual variation and limited available size range from some regions. Size-specific differences in otolith shape were found for the four regions for which a sufficient sample was available. Otoliths from Hawaii, French Polynesia, and NMI showed a significant shape affinity. Otoliths from Fiji and Vanuatu were similarly shaped and were distinct from those from the other three regions. Interregional otolith shape affinities for the stocks examined parallel similarities in maximum size and growth rate from the literature, suggesting that growth rate may influence otolith shape. Observed trends in otolith weight as a function of fish length support growthrelated regional differences in otolith shape. Des otolithes saginaux de quatre populations de vivanneaux du Pacifique (&te/is carbunculus Cuvier) ont ete compares a I'aide de descripteurs de Fourier et dautres indices de taille, des proportions lineaires et du poids sec. Des otolithes provenant d'Hawai;, du Vanuatu, des Fidji et de la Polynesie franqaise et un petit nombre du Commonwealth des iles Mariannes du Nord (IMN) ont ete examines. O n pouvait distinguer des caracteristiques regionales de forme et de poids, en depit de la grande diversite de variations individuelles et de la plage limit& des tailles disponibles pour certaines regions. On a observe les differences propres a I'espitce dans la forme des otolithes dans quatre regions pour lesquelles un echantillon suffisant etait disponible. Les otolithes dHawai, de la Polynesie franqaise et des IMN prkntaient une affinite de forme significative, alors que les otolithes des Fidji et de Vanuatu avaient des formes semblables et etaient distinctes de celles des trois autres regions. Les profils des affinites interregionales des formes d'otolithes des stocks examines sont semblables aux ressemblances des tailles maximum et des taux de croissance mentionn6es dans la documentation, ce qui suggere que le taux de croissance peut influencer la forme des otolithes. Les tendances observ&s du poids des otolithes en fonction de la longueur du poisson appuient l'hypothese des differences regionales en rapport avec la croissance pour expli-Can. I. Fish. Aquat. Sci. 49: 795-804. quer la forme des otolithes Received September 17, 7990 Accepted October 28, J 99 1 (JA725) he ehu (Erelis carbunculus) is a red snapper of the family Lutjanidae. The Etelinae, one of the four subfamilies of T Lutjanidae, comprise five genera: Aphareus, Aprion, Erelis. Prisripomoides. and Randallichrhys. Etelis carbunculus are captured from the coast of Africa as far east as Hawaii and French Polynesia, as summarized by Allen (1985). They represent one of the principal species in the commercial handline catch from steep, rocky slopes at depths of 200-450 m. Throughout the Pacific. Erelis carbunculus Cuvier (in Cuvier and Valenciennes 1828) has been referred to as Etelis marshi. Both Fourmanoir (1971) and Anderson (1981) pointed out that there were no significant morphological differences between specimens collected in the Pacific and those from the Seychelles Archipelago, previously described as Erelis carbunculus. Anderson's ( 198 1) clarification of the morphological distinctions between Etelis coruscans and Etelis carbunculus further reduced confusion regarding the 'Present address: State of Hawaii. Department of Land and Natural Resources, Division of Aquatic Resources, I151 Punchbowl Street, Rrn. 330, Honolulu, H I 96813, USA.
doi:10.1139/f92-090 fatcat:rc36iotpgbcvrabs3jwteu2rle