Back-calculated lengths-at-age for Walleye from Lake Mille Lacs, 2000-2011.

Description

Back-calculated lengths-at-age for Walleye (Sander vitreus) from Lake Mille Lacs. Walleye were captured by Minnesota Department of Natural Resources personnel in fishery-independent gillnets (five multifilament nylon mesh panels with each panel measuring 15.2 m wide and 1.8 m high; bar-measure mesh sizes of the panels were 19.1, 25.4, 31.7, 38.1, and 50.8 mm) set in the fall (mid September to early October) from 2000 to 2011.

Format

A data frame of 14583 observations on the following 9 variables:

• ID: A unique fish identification number.

• Year: Year of data.

• Sex: Sex (female, male).

• Est.Age: Estimated (from otoliths) age (yrs) at capture.
• TL: Total length (mm).
• Scale.Rad: Total scale radius (mm) at capture.

• Dist.Ann: Scale radius (mm) to annulus given in BC.Age.

• BC.Age: Annulus or previous age.

• BC.Len: Back-calculated length at BC.Age. Lengths were back-calculated using the Scale-Proportional Hypothesis method.

Topic(s)

• Growth
• von Bertalanffy
• Back-calculation

Source

These unpublished data are from the Minnesota Department of Natural Resources, Section of Fisheries (via Melissa Treml). Do not use for other than educational purposes without permission from the source.

Examples

data(WalleyeML)
str(WalleyeML)
head(WalleyeML)
xtabs(~Year+Est.Age+Sex,data=WalleyeML)