. The Canadian field-naturalist. 1984 Notes 495. Figure I. The four largest Orangespotted Sunfish captured in the Canard River, Ontario, in June, 1983. See Table 1, numbers 5 to 8, for lengths, etc. Grapples (Pomoxis annularis). Gizzard Shad (Doro- soma cepedianum). Green Sunfish (Lepomis cyanel- lus). Carp (Cyprinus carpio). Emerald Shiners (Notropis atherinoides), and Yellow Bullheads (Icta- lurus natalis). The specimens were identified by the conspicuous spotting pattern on their sides, their flexible opercular flaps, and lengthened preopercular sensory openings (Trautman 1981). Four of the
. The Canadian field-naturalist. 1984 Notes 495. Figure I. The four largest Orangespotted Sunfish captured in the Canard River, Ontario, in June, 1983. See Table 1, numbers 5 to 8, for lengths, etc. Grapples (Pomoxis annularis). Gizzard Shad (Doro- soma cepedianum). Green Sunfish (Lepomis cyanel- lus). Carp (Cyprinus carpio). Emerald Shiners (Notropis atherinoides), and Yellow Bullheads (Icta- lurus natalis). The specimens were identified by the conspicuous spotting pattern on their sides, their flexible opercular flaps, and lengthened preopercular sensory openings (Trautman 1981). Four of the specimens were photo- graphed (Figure 1), but voucher specimens were not saved. All of the fish weie measured (total length), weighed using a Mettler PC4400 DeltaRange top-loading bal- ance, sexed when possible by gamete extrusion and body colouration, and aged by the scale method (BagenalandTesch 1978) (Table 1). Fish which could be sexed were greater than the 48 mm minimum size at maturity quoted by Lee et al. (1980). The presence of several age classes, and numbers of sexually mature adults, are indicative of a possible reproducing popu- lation. The weight-length regression equation was: logioW = + logioTL. Both the slope and correlation coefficient significantly differed from zero (p< , t-test, two-tailed). These results are simi- lar to those reported by Carlander (1977). Trautman (1981) stated that the first Orangespotted Sunfish recorded in the Lake Erie drainage basin were sampled in 1929 in Lake St. Marys, Ohio, from which rapid range expansion northeastwards through that state occurred. Before its discovery in Cedar Creek, Ontario (Holm and Coker 1981), its most northerly reported progress had been to Lake Erie's South Bass Island area in 1952 (Trautman 1981). If the present population is derived from that reported by Holm and Coker (1981), three possible routes to the Canard River site exist: (1) Cedar Creek to Lake Erie, up the Detroit River, an
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