This dataset reports estimates of yellow perch abundance and length-at-age for different stage and age groups in Oneida Lake and is part of the collection "Cornell Oneida Lake Data". The Cornell Biological Field Station (CBFS) serves as a primary field site for aquatic research at Cornell University (more information can be found at http://www.dnr.cornell.edu/fieldst/cbfs.htm) and is part of the Department of Natural Resources, College of Agriculture and Life Sciences. The centerpiece of the station's research program is a 60 year database on the food web of Oneida Lake, New York, that has been collected with support from the Cornell University Brown Endowment and from the New York State Department of Environmental Conservation. The data are collected by personnel from the Cornell Biological Field Station and include limnology, benthos, zooplankton, phytoplankton, and fish survey data, primarily from Oneida Lake and spanning 1957 to the present. The estimates in this dataset are based on data from standard trawl (since 1961) and gill nets catches (since 1959) (Trawl and Gillnet Data-packages in the same collection), mark-recapture estimates for age 3 and older yellow perch, an analysis of gill net selectivity and mark-recapture estimates for age 3 and older perch, and Miller sampler surveys for larval yellow perch when the fish are approximately 8 mm and 18 mm. There are two data tables. The first contains abundance and length-at-age for age 1 and older perch. The second contains abundance, length, and sampling dates for the first year of life (larvae, juveniles, age-1 in the following spring).