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LAKE STURGEON. Gul 
Acipenser rupertianus, RICHARDSON (1836), Fauna Bor.-Am., Fishes, 311, and of several 
authors. 
Acipenser liopeltis, GUNTHER, Cat. Fishes Brit. Mus., viii, 341. 
Description —Snout rather short and bluntish, forming less than half the length of the 
head in the adult, longer and more pointed in the young ; barbels long, nearer the snout 
than the eye; bony shields moderate, rather smooth; shields with the pointed keel 
nearly central, and directed rather upwards than backwards; skin with numerous 
prickles and stellate ossifications ; about 13 shields in the dorsal row (before dorsal fin) ; 
34 in the Jateral series and 9 in the ventral; the plates becoming smoother with age, 
and in very old specimens, most of them finally falling off; anal fin mestly below the 
dorsal; caudal fulcra, not remarkably developed. Length, two to six feet. 
Habitat, Great Lakes, Upper Mississippi and northward, very abundant in the Upper 
Lakes, ascending the tributary rivers in large numbers to spawn in the spring. 
Diagnosis.—The Lake Sturgeon is distinguished from the Sea Sturgeon 
(A. sturio, L.), by its smaller size and the greater number of plates in the 
lateral series (about 34 instead of 28). From the Ohio River Sturgeon, 
it may, perhaps, be known by the central position of the spinous keel to 
the plates. This character (first noticed by Professor Milner), may be 
simply due to the greater age of the specimens examined, as the plates 
certainly grow smoother, and the spines more central with increased age. 
Habits—In Ohio this species occurs only in Lake Erie and iis larger 
tributaries, the Sturgeon of the Ohio River being considered, whether cor- 
rectly or not, as belonging to another species. The following account is 
abridged from the notes of Prof. Milner (Rept.Commr. Fish and Fisheries, 
1872-73) : 
‘This Sturgeon attains the largest size of any fish of the lakes. They are taken only 
within comparatively shoal waters, and in some of the bays and among the islands they 
are very abundant, The largest specimen it has been my fortune to see did not quite at- 
tain the length of six feet, though there are traditions in localities en the lakes of nine 
foot Sturgeons. The average of the mature ones taken is less than five feet. In numbers 
they will not compare favorably with any of the staple food-fishes. At Sandusky, Ohio, 
where they are more numerous than in any other locality, except, perhaps, Green Bay, 
Wis., there were about 14,000 mature Sturgeons handled, weighing about 700,000 pounds, 
obtained from about 85 pound-nets.” 
Their food consists almost entirely of the shell-fish of the lakes, prin- 
cipally Gasteropods, the thinner-shelled kinds of the genera Physa, Planor- 
bis, and Valvata being found broken in the stomachs, while Limnxa and 
Melantho remain whole. Weegs of fishes are sometimes found, but it is 
probable that they are not extensively spawn eaters. 
The spawning season in Lake Erie occurs in June. They then ascend 
the various tributary rivers as far as the depth of the water and the 
various obstructions will permit, in large schools, and may often be seen 
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