BAGO a ah UCP Ss neth,? yelee a a “Ete men erm e oy A a os ery gat ate opener CO Ag OE POR ah ea re ory pa owe rapa Yar " ele AEE AG PP AM Be pm adage. ee —iiligdniaeiadas+hemumredele oa ee ate) Sha eh Peat Ne Sere w tae OO iF ee eek ah eee ee Sg ON eRe, aS ee ewe, ee eee satieninlnatrtie oh Le mma haat fe Oe ON POD ge OO pteihinted shunt eet oe ea ct en eet a — we a nore P= OP ee a eee tee > ec ee 2 opine ge 6 a Pals ces etas cota nn Lado. — nd oa te Ma gh PPE OP 5 oF FT - eta ee ee eS oe enaigiliidt ies ee eee ee ee ee on oe a eae ee OAS e o> Tete ile oe <0, ng. FE Ca 2 tae Toe ON Se ing int sah atch bee! > ot wie (om Be cee wee ite seine 8 nat t «he no arie. o> le ll ot arg eS A et a a) - oe tay lke Oo eel eek hm es ~ eben” « a a 2 oe ole ane y yy a en aeteien ee ee aa am — x . Pee fire a ee ew Od ir mats ts . - meas Sting lia eo SO EN ” she lt dss cain Ser _ SF ahs a 6 Oat le ada en eee a ae ee pame rte tha ere Digitized by the Internet Archive In 2011 with funding from University of Toronto http://www.archive.org/details/unusualmaskinongOOcame ry : ie ei Ca Nya ak yh Ae a “i ‘ ht A S nH eee a SR a a ; j mi a AMIS | ee WI ge nie 05013 5714 E Ss CONTRIBUTIONS OF THE: ROYAL ONTARIO MUSEUM OF ZOOLOGY ’ _ No. 31: AN UNUSUAL MASKINONGE FROM LITTLE VERMILION LAKE, ONTARIO By G. S. CAMERON ¢ $k Peete Reprinted from Canadian Journal of Research, D, 26:223-229. October, 1948. ee : 1948 Reprinted from Canadian Journal of Research, D, 26 : 223-229. October, 1948 Published by the National Research Council of Canada AN UNUSUAL MASKINONGE FROM LITTLE VERMILION LAKE, ONTARIO! By G. S. CAMERON? Abstract An unusual type of maskinonge found in two lakes in Kenora District, Ontario, is regarded as a hybrid between Esox masquinongy and Esox lucius. It differs from the typical maskinonge found in the same waters in having a stouter body, longer and deeper head, longer maxillary, and longer fins. It retains dark vertical bars throughout life whereas in the typical form these break up and tend to disappear with age. Of 69 specimens examined, six were of the presumed hybrid type. These all appeared to be sterile. They showed the following Esox lucius characters—cheeks totally scaled, head concave interorbitally, cheeks and opercula vividly marked. The presence of an unusual type of maskinonge in Little Vermilion Lake, Kenora District, Ontario, was brought to general attention in 1945, when it was described as a new species, Esox amentus, by Godfrey (3). During the summer of 1946, two months were spent on Little Vermilion Lake and a number of other lakes in the vicinity in connection ‘with a taxonomic study of maskinonge undertaken by the Royal Ontario Museum of Zoology with the financial support of the Carling Conservation Club. The accompanying map indicates the location of these lakes, which drain by way of the English River, the Winnipeg River, Lake Winnipeg, and the Nelson River into Hudson Bay. In the course of these studies, 69 specimens of maskinonge from Little Vermilion Lake, and a smaller connecting lake, known as Maskinonge Lake (Musky Lake), were studied. The study included the making, on each specimen, of 28 measurements of such body proportions as head length, head depth, diameter of eye, length of snout, length of maxillary, body depth and width, caudal peduncle depth and length, and height and base of dorsal, anal, pectoral, and ventral fins. In addition, counts were made of scales in the lateral line, of branchiostegals, and of fin rays. Measurements and counts were made as described by Dymond (1). A description, including a photo- graph, was made of the markings and color pattern of each specimen. Age was determined also, by scale examination. 1 Manuscript received March 16, 1948. Contribution No. 3§ of the Royal Ontario Museum of Zoology, Toronto, Ont. 2 Junior Zoologist (Seasonal) Royal Ontario Museum of Zoology. 224 CANADIAN JOURNAL OF RESEARCH. VOL. 26, SEC. D. p p(CLOUDLET LK. Muo (HoocH) LAKE Musky LAKe \ gig pes @ MasKinonce oa ‘a * we ® Tryve T1GER MASKINONGE ne O Pike Map of Little Vermilion and surrounding lakes. Table I presents a comparison of the body proportions and counts of the common and of the so-called ‘true tiger’ or amentus maskinonge. In the case of the common type, only average and extreme ranges are given. A comparison between a number of these body proportions in the two types is presented graphically in Figs. 1, 2, and 3. The table and figures indicate several significant differences between the common or typical maskinonge of Little Vermilion and Maskinonge lakes and the so-called ‘true tiger’ (amentus) variant, occurring in the same waters. As compared with the typical form, the variant has a much stouter body (deeper and wider in proportion to length), with a longer and deeper head, much more sharply concave interorbitally, longer maxillary (reaching a vertical through the posterior margin of the eye), and a caudal peduncle both shorter and deeper. The fins are all longer, with larger bases, while the scale count seems slightly lower. Other differences include the complete scaling of the cheek of the variant as compared with the naked lower half of the cheek of the typical form. The color and markings of the two forms are quite different. Small specimens of the typical form (up to about 30 in. in length) are predominantly bluish green on the sides with distinct dark vertical bars (Fig. 4). Larger fish show a gradual darkening of color, while the markings become gradually bo bo mn CAMERON: MASKINONGE TABLE I COMPARISON OF BODY PROPORTIONS AND COUNTS OF SCALES AND BRANCHIOSTEGALS OF THE COMMON TYPICAL MASKINONGE OF LITTLE VERMILION AND MASKINONGE LAKES AND OF THE SO-CALLED ‘TRUE TIGER’ OR amentus TYPE FOUND IN THE SAME LAKES All body proportions listed are expressed as thousandths of standard length; standard length in mm. Common type “True tiger’ (amentus) type Average} Range Field number = — 037 024 O75 042 050 035 | Mean Standard length 769 | 631-1022 | 850 862 885 904 908 911 887 Head length 276 252-309 315 321 329 303 S15 324 318 Head depth 112 092-129 127 i Ble 138 125 143 L122 128 Eye 029 | 024-032 027 028 030 029 026 025 028 Snout PTS 104-126 137 | 142 140 142 142 140 Interorbital 067 | 061-074 072 074 073 075 072 073 073 Maxillary 132 109-145 166 166 167 167 168 170 167 Snout to occiput 190 | 183-201 222 219 229 226 225 228 225 Body depth 183 163-222 188 209 206 204 193 200 200 Body width 105 | 089-122 108 115 120 123 120 113 116 Caudal peduncle length 124 | 103-147 108 122 119 132 123 122 121 depth 074 | 063-083 O71 075 082 076 085 076 078 Dorsal rays 22 19- 23 Ip. 22 23 22 23 22 22 height 115 099-129 119 119 134 134 121 128 126 : base 120 | 109-141 132 133 Swi 128 140 133 134 Ana rays 20 18- 22 Zi 20 20 20 2A 2h) 20724 height 114 | 096-130 119 120 134 127 112 122 bee base 099 | 090-120 104 104 110 108 098 094 104 Pectoral rays 18 16- 19 18 18 18 17 18 18 18 height 115 -| 101-132 114 130 139 133 118 132 128 base 036 | 030-043 042 042 042 039 035 039 040 Ventral rays 12-13 12- 13 12 12 12 12 12 12 12 height 100 | 089-117 101 112 119 118 110 120 113 base 036 | 031-040 039 037 037 038 035 038 037 Scales 149 | 137-156 143 150 143 146 140 145 145 Branchiostegals t7-16 16- 19 | 19/18} 19/20} 18/19) 18/17} 18/17} 18/18} 17/18 obscured (Fig. 5). The back is often so dark a shade of olive green as to be almost black. This color shades down through bronze to sides that have a ruddy ground color. As a fish ages, the bars break up into obscure blotches, which remain more distinct in the caudal region (Fig. 6). In the largest specimens (over 40 in.) the sides are usually of a uniform dirty brownish color. The belly is usually white, although that of some young maskinonge is marked by faint dark patches. The fins are typically of a brownish color with obscure darker blotches; the fins are often of a vivid red color. The variants are given the name ‘true tiger’ because they possess permanent distinct dark crossbars (Fig. 7) traversing light-colored sides, which show a subtle bluish tint. This light color darkens dorsally through a purple hue to a back that is so deep a purple as to appear black. The bars arise from this 226 CANADIAN JOURNAL OF RESEARCH. VOL. 26, SEC. D. black back and slope downwards and forwards, occasionally being broken by distinct dark spots. These markings are sometimes described as ‘worm- tracks’. The cheeks and opercula are covered with distinct dark blotches, while the fins are less reddish than those of the typical form, and are faintly spotted. HEAD LENGTH (MM.) STANDARD LENGTH (MM.) Fic. 1. Diagram showing relation between head length and standard length in typical maskinonge (small dots ) and ‘tiger’ maskinonge (large dots ). MAXILLARY LENGTH (MM.) STANDARD LENGTH (MM.) Fic. 2. Diagram showing relation between maxillary length and standard length in typical maskinonge (small dots ) and ‘tiger’ maskinonge (large dots ). Through the co-operation of anglers fishing for maskinonge on Little Vermilion and Maskinonge lakes, and local resort owners, a considerable proportion of the specimens caught and retained were made available for examination. So keen are anglers to exhibit their catch of a rare ‘true tiger’ that every specimen of this variant taken during the time the study was in progress was photographed and examined. ‘The fact that of the 69 specimens examined only six were of the ‘true tiger’ type indicates that this type is comparatively rare. This rarity, together with the striking beauty of the CAMERON: MASKINONGE 227 fish makes it a prize eagerly sought after, and may in part explain its reputation for superior fighting qualities. Actually, experienced guides insist that both ‘true tiger’ and common maskinonge fight with equal vigor. HEIGHT OF ANAL FIN (MM.) SAL FIN (MM.) HEIGHT OF DOR- STANDARD LENGTH (MM.) Fic. 3. Diagram showing relation between height of anal and dorsal fins and standard length in typical maskinonge (small dots) and ‘tiger’ maskinonge (large dots ). A striking feature of these variants was the fact that their gonads were so small and shrivelled as to suggest that they were nonfunctional. The texture was quite different from that of the gonads of normal specimens of the same size. So far as is known this variant is confined to Little Vermilion and Maskinonge lakes although there were reports of its occurrence in Cliff and Height of Land lakes. Until specimens from these waters can be examined it will not be known whether these are of the same nature or merely vividly marked young of the typical form. Several of the characters in which the so-called ‘true tiger’ maskinonge of Little Vermilion and Maskinonge lakes differ from the typical form suggests that it is a hybrid between the common maskinonge (Esox masquinongy) and the pike (Esox luctus). The pike is not known to occur normally in Little Vermilion and Maskinonge lakes, although it abounds in the lower neighboring lake, Big Vermilion, separated from Little Vermilion by a low falls. Little Vermilion and Maskinonge lakes are joined by a long meandering creek. At high water in spring when these fish spawn it is quite possible that occasional pike may gain entrance to the Maskinonge lakes above. Some of the considerations that suggest that the ‘true tiger’ (amentus) maskinonge is a masquinongy-—lucius hybrid are as follows. It appears to be sterile. It possesses the following characteristics of Esox lucius—cheeks totally scaled, head sharply concave interorbitally, cheeks and opercula vividly marked. The scale count is intermediate between /uctus and masquinongy. 228 CANADIAN JOURNAL OF RESEARCH. VOL. 26, SEC. D. Presumed lucitus—masquinongy hybrids are known in other waters and have been produced artificially. Eddy and Surber (3) say that late-maturing pike have been reported as spawning with maskinonge and that evidence of hybri- dization has been found in the frequent appearance of specimens bearing maskinonge markings but having the cheeks entirely scaled as in the pike. These authors further report that a large number of maskinonge eggs were successfully fertilized with pike milt at the Nevis Hatchery and that pike eggs were likewise successfully fertilized with maskinonge milt. Some of the resulting fish were reared in the vicinity of the Nevis Hatchery and some in tanks and ponds at the University of Minnesota. Some of the characters shown by underyearlings of these hybrids have been reported by Eddy (2, pp. 25-27) as follows: ‘‘Both of the crosses were heavily barred. Some had the scales absent from the lower part of the cheek, but many showed the lower part of the cheek to be covered partially or entirely by scales.’”’ By Sept. 15 the hybrids were between 11 and 12 in. in standard length whereas the pure bred lunge were between 7 and 8 in. in standard length. The heavy barring and the scaling on the lower part of the cheeks of the artificially produced hybrids correspond to the condition found in the pre- sumed hybrid here reported. The increased rate of growth and apparent infertility of the presumed hybrid correspond to the condition found by Hubbs and Hubbs (5) in the case of hybrid sunfish. , While the evidence for an increased growth rate in the case of the presumed hybrids reported here is not as great as in the case of the artificial hybrids during their first year there is some indication of it. The six specimens of the amentus type, ranging in standard length from 850 to 911 mm. were from 8 to 11 years of age, whereas six typical maskinonge from the same waters 860 to 911 mm. in length were 9 to 14 + years of age. Four of the seven peculiar maskinonge reported by Seaborn (6, p. 237) were probably pike—maskinonge hybrids as indicated by the barred pattern and the complete scaling of the cheeks. Acknowledgments I wish to thank Prof. J. R. Dymond, Director of the Royal Ontario Museum of Zoology, for his guidance in the investigation of this problem, and in the preparation of this report. Gratitude is also due to Mr. Shelley Logier, Royal Ontario Museum of Zoology, who has prepared the figures, and to all those whose co-operation during the investigation was so generously given. These include Mr. Mike Ament, Mr. George More, the late Mr. Howard Noreton, Mr. Archie McDonald, Mr. Ernie Calvert, and numerous others. ‘suamliaads AasAD] UL SADQ 1091}/a2 YADP fo aqua}sis 3 e . ~ fan : °) °r : / . Ss 8 ° F ‘ fi ‘ Say lee ar -4ag durmoys ‘Fuo] “ur Fog ‘udof (snpuaun ) Aas and, “1 “OT “Sag 10914400 Yavp fo sarDAq Kjuo surmoys ‘suop ‘ur Sep ‘umsof pondk] “9 “OY “Sag jpayaan yap fo Surpluad Surmoys ‘suop “ur “pe Udo pondk °C "OI *S4Nqg JvII44aa YADp fo Udsayvg HUuIMoYS ‘HUO] “UI FY mséof jodk [ *F “O1 | ALVIq ~~ or we W bo nN CAMERON: MASKINONGE 229 References . Dymonp, J. R. The coregonine fishes of northwestern Canada. Trans. Roy. Can. Inst. 24 :171-231. 1943. . Eppy, S. Do muskellunge and pickerel interbreed? Prog. Fish-Cult. No. 48. 1940. . Eppy, S. and SuRBER, T. Northern fishes. Univ. Minn. Press, Minneapolis. 1943. . GoprrEY, J., JR. Muskies unlimited. Outdoors. Oct. 1945. . Husss, C. L.and Husss, L.C. The increased growth, predominant maleness and apparent infertility of hybrid sunfishes. Papers Mich. Acad. Sci. 17 : 613-641. 1933. . SEABORN, E. Variations in the maskinonge of the Sauble River, Ontario. Copeia, 1937, No. 4. 1937. Vo) 9 a.» VEN ie AG Ly we i fg oA ue | o. 4 ih Ns ss. £m fk” OB. / Saat” ae Cie Dak eens a ae uf , * io S , f , a, J oe \ Lo 4 > 4 ie a" 2 ? ce “ * -. Sv ¥ . a > dy : ~ ‘ e . “ s 7 ‘ } . , s ' » N > a - - . . - “ 4 \ te y eat 5 vf i 7 | ' Bite: an Atay } ib funy Wis ra 9 hk; yi Wi wa t ‘} eh GAT Te Mt py af See wee see et 2 IS Se Oe ee ee a ae MF 2 Eanes eee.” us oy : - = eRe dette 7 ~ : ase - per yom - > oa . si id ’ ° Ami srs Sets . noni : le: ones a aa = a 2 See Ne : : . & = : - . = e A © 3 : 5 ethane tw elo a . rag ee ante ens on ie _ : : ea ea cai satiate : 7 ‘i ie oa ear wt? ig oe veers eae ee Ay > Lita ne 3 TELE tat sta rs Aa : : edt eNllmece 4 ne ae Re tee eae waren i=: E ig : Sched “37a tt das : ap cae eee nS ine eae EA ye, Salts rR tS NH PRREREN Rigo N EN > : 2 i = OR Re =: ro aes sabesietiatadsces Ea B? on ee * ~ + Sar tas 7 a eed Z 2 orto as : = - ” ee GS os sete <2 RISERS HAS Sey PE HPSS eek stan, 2 ect Co al Seater < ve wade: whe: SEES De SAPs oe, NS 4 SAN Sat ores