Finescale Dace (Phoxinus neogaeus)
The finescale dace range extends from Maine and New Brunswick west through the northern United States and southern Canada to Hudson Bay and the Mackenzie River drainage, with disjunct populations occurring in South Dakota and Nebraska. New York records occur mostly within the northern Adirondacks and the St. Lawrence Valley, with one 1930s record in the Allegheny drainage.
The finescale dace is a northern species that does best in sluggish, darkly stained, swampy streams. It also occurs in ponds and lakes.
Spawning takes place in late April and early May when the water temperature is about 15° C. The fish were observed in a beaver pond where the bottom was fine silt, with fallen trees for cover and some rocks and brush. The fish also spawned in flower pots in laboratory aquariums 2 m by 1 m by 0.7 m deep. In the wild, the sex ratio was 1.5 males to 1 female. The fish milled around in a large school and, at intervals, one or two females left the school. They were pursued by several males who chased them under shelter where the females remained for about 15 seconds and the males stayed for about 30 seconds. In the laboratory, the male could be seen to guide the female with his pectoral fin under her belly, behind her pectoral fins. The female was crowded against some object with the tail of the male over her tail so that the tubercles on his anal fin rubbed against her vent region. The female vibrated for about 10 seconds, then moved away, while the male continued to vibrate and emit milt for another few seconds. Each spawning episode resulted in the release of 30 to 40 eggs which sank to the bottom. The eggs were about 1.4 mm in diameter and hatched in 6 days at 20° C. Each female contained 784 to 3,060 eggs, depending on the size of the female.
Insects and small crustaceans have been found in the stomachs of finescale dace.
Distribution of in finescale dace NY state. Dark dots represent where finescale dace have been collected. White dots represent historic distributions.
A 130 KB image of the finescale dace is also available for download.
The above species description was taken out of "The Inland Fishes of New York State" by C. Lavett Smith, published by the New York State Department of Environmental Conservation, 1985.