Food habit analyses of the young-of-the-year alewife in lake Michigan show zooplankton was the primary component of the diet in 1972 and 1973. Cyclops bicuspidatus contributed the largest portion of the diet in both years. The dominant cladocerans consumed in each year were Bosmina longirostris, Daphnia retrocurva, Chydorus sphaericus, Polyphemus pediculus, and Diaphanosoma brachyurum. Diaptomus spp. was the only other copepod of importance. Chironomid larvae and pupae provided minor volumes in both years.Monthly food habits revealed a general decline in cladoceran percent volume from August to October at the Michigan City and Dunes transects. Bosmina longircstris was the predominant cladoceran in August of both years at both stations. Chydorus sphaericus was a major food item in September, 1972 at the Michigan City transect, and August and September, 1972 at the Dunes transect. Daphnia retraocurva was a primary prey species in August of each year and in September, 1973 at Michigan City, and in August and September of both years at the Dunes transect.Polyphemus pediculus percent volume was greatest in August and September, 1973 at both stations. At the Michigan City transect, Cyclops bicuspidatus was the dominant food item, and was more important in September than August in both years. In contrast, C. bicuspidatus contributed a major portion of the alewife diet at the Dunes transect in each year, but was more important in August than September. Diaptomus spp. percent volume was greatest at the Michigan City transect in October of both years. Chironomids were major food items only in August, 1972 at the Dunes transect.Young-of-the-year alewife food habits in relation to fish length indicated that smaller YOY alewives selected smaller cladocerans and copepods, whereas larger alewives preferred larger cladocerans, copepods, and chironomids.Ball State UniversityMuncie, IN 47306
| Identifer | oai:union.ndltd.org:BSU/oai:cardinalscholar.bsu.edu:handle/181263 |
| Date | 03 June 2011 |
| Creators | Coleman, Dennis A. |
| Contributors | McComish, Thomas S. |
| Source Sets | Ball State University |
| Detected Language | English |
| Format | viii, 78 leaves : map ; 28 cm. |
| Source | Virtual Press |
| Coverage | n-us-in nl----- |
Page generated in 0.0022 seconds