FAO Fisheries Synopsis No. 41 BCF/S 41 SAST Chum ea1mon - 1,23(O1),009,03 SYNOPSIS OF BlOLOGîCAL DATA ON THE CHUM SALMON,, Oncorhy.nchus kéta (Wàîba urn) 1792 UNITED STATES DEPARTMENT OF THE INTERIOR U.S. FISH AND WILDLIFE SERVICE BUREAU OF COMMERCIAL FISHERIES Circular 315 UNITED STATES DEPARTMENT OF THE INTERIOR Walter J. Hickel, Secretary Russell E. Train, Under Secretary Leslie L. Glasgow, Assistant Secretary for Fish and Wildlife, Parks, and Marine Resources Charles H. Meacham, Comlni8eioner, U.S. FISH AND WILDUJFE SERVICE Philip M. Roedel, Director, BUREAU OF COMMERCIAL FISHERIES Synopsis of Biological Data onthe Chum Salmon, Oncorhynchus keta (Walbaum) 1792 By RICHARD G. BAKKALA FAO Species Synopsis No, 41 Circular 315 Washington, D.C. March 1970 CONTENTS Pag e Introduction i Identity i 1.1 Nomenclature i 1.2 Taxonomy i 1.3 Morphology 5 2 Distribution 8 2.1Total areas 8 2.2 Differential distribution 9 2.3 Determinants of distribution 10 2.4 Hybridization il 3 Bionomics and life history 12 3.1 Reproduction 12 3.2 Preadult phase 24 3.3 Adult phase 28 3.4 Nutrition and growth ¿9 3.5 Behavior 39 4 Population 42 4.1 Structure 42 4.2 Abundance and density (of population) 46 4.3 Natality and recruitment 50 4.4 Mortality and morbidity 51 4.5 Dynamics of population 57 4.6 Population in community and ecosystem 59 5 Fishery 60 5.1 Fishing equipment 60 5.2 Fishing areas 64 5.3 Fishing seasons 65 5.4 Fishing operations and results 65 6 Protection and management .. 73 6.1 Regulatory (legislative) measures 73 6.2 Control or alteration of physical features of the environment 73 6.3 Control or alteration of chemical features of the environment 74 6.4 Control or alteration of the biological features of the environment 74 6.5 Artificial stocking 74 7 Pond fish culture 76 Literature cited 76 'il. Synopsis ofBiologicalData on the Chum Salmon, Oncorhynchus keta(Walbaum) 1792 By RICHARD G. BAKKALA, Fishery Biologist Bureau of Commercial Fisheries Biological Laboratory Seattle, Washington 98102 ABSTRACT Information presented on the chum salmon includes nomenclature, taxonomy, morphology, distribution, ecology and life history, population dynamics, fishery, and protection and management. INTRODUCTION i IDENTITY The Fisheries Biology Branch of FAO has 1.1 Nomenclature formed a "Synopsis Association," composed of fishery agencies willing to contribute to the 1.11Valid name preparation of synopses on fishes and other Oncorhynchus keta (Walbaum) Jordan and Gil- aquaticorganismsofcommercialvalue. bert (1882: 305, fig. 1). Several organizations, including the U.S. Fish and Wildlife Service, Bureau of Commercial 1.12 Synonymy Fisheries, have agreed to collaborate with FAO Adapted from Jordan and Evermann(1896). inthisundertaking. Synopses prepared by Bureau personnel will be published in the Salmo keta vel kayko Walbaum(179272). circular series and will follow the format pre- scribed by Rosa (1965). Salmo lagocephalus Pallas (1811: 372). Salmo japonensis Pallas (1811:382). The primarypurposeofthis series is to make existinginformation r e a di ly available to Salmo consuetus Richardson (1854:167). fishery scientistsaccording to a standard format, and thereby to draw attention to gaps Salmo dermatinus Richardson(1854: 169), in knowledge. It is hoped that synopses in thig Salmo canis Suckley (1862: series will be useful to scientists initiating 9). investigations of the species concerned, or of Oncorhynchus lagocephalus G'únther (1866: related ones, as a means of exchange of knowl- 161), edge among those already working on the species and as the basis for comparative study Oncorhynchus keta Jordan and Gilbert (1882: of fishery resources. 305). 1.2 Taxonomy The chum salmon (Oncorhynchus keta) spawns in five countries (the United States, 1.21 Affinities (According to Berg, Canada, Japan, Korea, and the U.S.S.R.) and 1947) is most abundant on theAsian continent; there- fore, a complete synopsis on its biology should Suprageneric be based on studies from all five countries. I Phylum Verteb rata tried to achieve this aim as nearly as possible. Subphylum Craniata My review of the literature was restricted, Superclass Gnathostomata however, to the studies published in English Series Pisces or to the Japanese and Russian studies that Cias s Teleostomi had been translated into English. Consequently Subclass Actinopterygii some important information has undoubtedly Order Clupeiformes been omitted, and I hope that it willbe added Suborder Salmonoidei to the synopsis when it is updated inthe future. Family Salmonidae i Figure l.--The chum salmon, Oncorhynchus keta (Walbaum). (Photograph courtesy of National Fisherman) Generic Pacific in North America and Asia, spawning in the fall." Oncorhynchus Suckley, 1861 (1862:313) Specific Genotype: The type specimen is SalmoketaofWalbaum Salmo scouleri (Richardson) (1792: 72) from the Kamchatka River. The original description, as cited by Okada (1960) The generic name is derived from Greek is: Onkos (hook) and rhynchos (snout). Salmo keta VEL KAYKO WALBAUM The generic concept used here is that of 0. 14. P. 15. V. 11. A. 18. Jordan and Evermarin (1896): "Caput breve, obtusum. Corpus immac- "Body elongate, subfusiform, or com- ulatum. Cauda Lunata. Caroalba. pressed. Mouth wide; the maxillary long, Squamae argenteae. Dorsum viridescens. lanceolate, usually extending beyond the Capitur copiose in flumininbus Kamtsch- eye; jaws with moderate teeth, which be- atkae. come in the adult male enormously en- larged in front. Vomer long and narrow, "Salmo keta VEL KAYKO, Kraschein- flat, with a series of teeth both on the nikow, l.c. pag. 181. Salmonem Narkam head and the shaft, the latter series com- magnitudine aliquatenus superat: Caput paratively short and weak; palatines with oblongum, planum. Rostrum resimum, a series of teeth; tongue with a marginal Dentes, post quam aliquamdin in flumine series on each side; teeth ori vomer and moratus est, canins similes fuint. Lingua tongue often lost with age; no teeth on the acuta. Cauda parum bifurca. Dorsum hyoid bone. Branchiostegals more or less atro-viride, latera & abdomen similiter increased in number. Scales moderate or colorata ac allis selmonibus sed absque small. Dorsal fin moderate; anal fin maculis." comparatively elongate, of 14 to 20 rays. Pyloric appendages in increased number. Species diagnosis according to Clemens and Gill rakers rather numerous. Ova large. Wilby (1946): Sexual peculiarities very strongly devel- oped; the snout in the adult males in sum- "Body elongate, somewhat compressed; mer and fall greatly distorted; the pre- caudal peduncle slender, Head conical; maxillaries prolonged, hooking over the mouth terminal; teeth conical, strongly lower jaw, which in turn is greatly elong- developed, becoming fang-like in mature ate and somewhat hooked at tip; the teeth males; branchiostegals, 10 to 16; rakers on these bones also greatly enlarged. The on first gill arch, 19 to 26, short, stout, body becomes deep and compressed; a smooth, widely spaced. Fins: dorsal (1), fleshy hump is developed before the dor- 10 to 13; adipose, small, slender, fleshy; sal fin, and the scales of the back become anal,13 to17; pelvic, abdominal, each embedded in the flesh; the flesh, which is with fleshy appendage atbase;caudal, red and rich in spring, becomes dry and emarginate. Lateral line: slightly de- poor. Salmon, mostly of large size, as- curved, then straight. Scales: cycloid; in cending the rivers tributary to the North first row above lateral line, 130 to 153; ¿ on lateral line, 126 to 151. Pyloric caeca: Lateral-line scales 130- 147 (average 140 to 185. Colour: metallic blue on dor- about 139); branchiostegals 10-16; sal surface with occasional black speck- pyloric caeca 140-254 (average about Ungs; no black spots; black tinge on tips 205); anal rays 16-20 (complete of pectoral, anal and caudal fins, especi- count);gill rakers 19-26 (average ally in male; in maturing adults in fresh about22), rakers wide apart and water irregular reddish to dusky streaks without teeth; caudal peduncle slen- or bars across sides of body, white on der; parr marks short, elliptical or tipsof pelvic and anal fins. Flesh pale oval, extending little, if any, below pink. Young with parr marks as slender lateral line; no black speckling on bars,scarcely extending below lateral back or fins; breeding color anterior line and green iridescence on back. two-thirds of sides with bold jagged reddish line, posterior third of sides with jagged black line; mouth lining 'Length to 3 feet 2 inches. dark; obligatory anadromous, long seamigrations, abundant far off- "Distinguished by the absence of large shore Oncorhynchus keta, chum black spots from the body and the fins, salmon. the slender caudal peduncle, the tips of CC. Lateral-line scales 130- 165(average all fins except dorsal tinged with black, about 146); branchiostegals13-19; the series of dusky streaks or bars pyboric caeca 85-244 (average about across the sides of the body in mature 158);anal rays16-22 (complete adults in fresh water, the 20 to 26 smooth count);gill rakers 20-28 (average widely spaced rakers on the first gill about 24), rakers wide apart with arch, and the large number of pyloric large teeth; caudal peduncle stout; caeca. The young are readily recognized parr marks large vertical bars al- by the slender parr marks, scarcely ex- most bisected by lateral line; small tending below the lateral line, and the black speckling on back, dorsal fin, green iridescence on the back." and upper lobe of caudal fin, some- times extending onto adipose fin and The following key to the species of Oncor- lower lobe of caudal and faintly onto hynchus in North America is from Rourisefell anal fin; breeding adults without red (1962). on sides; mouth lining black; obliga- tory anadromous; long sea migra- "A. Lateral-line scales 160-198 (average tions; not abundant far offshore- -On- about 184); branchiostegals 9-15;py- corhynchustshawytscha, king bric caeca 95-224 (average about salmon.