# Lengths for Walleye, Yellow Perch, Black Crappie, and Black Bullheads from Lake Herman, SD.

Source:`R/Herman.R`

`Herman.Rd`

Total lengths of Walleye (*Sander vitreus*), Yellow Perch (*Perca flavescens*), Black Crappie (*Pomoxis nigromaculatus*), and Black Bullheads (*Ameiurus melas*) for four years in Lake Herman, SD.

## Format

A data frame of 5931 observations on the following 3 variables:

- tl
Total lengths (cm).

- spec
Species codes (

`wae`

=walleye,`yep`

=yellow perch,`bkc`

=black crappie, and`bbh`

=black bullhead).- yr
Capture years.

## Source

From a South Dakota Fish and Game report. CSV file

## Details

Lake Herman was sampled on June 20-22, 2005 with four overnight gillnet sets and 10 overnight trapnet sets. The trapnets were constructed with 19-mm (0.75 in) bar-mesh netting, 0.9 m high x 1.5 m wide (3 ft high x 5 ft wide) frames and 18.3 m (60 ft) long leads. The gillnets were 45.7 m long x 1.8 m deep (150 ft long x 6 ft deep) with one 7.6 m (25 ft) panel each of 13, 19, 25, 32, 38 and 51-mm (0.5, 0.75, 1, 1.25, 1.5, and 2 in) bar-mesh monofilament netting.

## Examples

```
data(Herman)
str(Herman)
#> 'data.frame': 5931 obs. of 3 variables:
#> $ tl : num 16.6 19.2 20.1 21.1 27.7 27.5 28 29.7 30.3 31.4 ...
#> $ spec: Factor w/ 4 levels "bbh","bkc","wae",..: 3 3 3 3 3 3 3 3 3 3 ...
#> $ yr : int 1999 1999 1999 1999 1999 1999 1999 1999 1999 1999 ...
head(Herman)
#> tl spec yr
#> 1 16.6 wae 1999
#> 2 19.2 wae 1999
#> 3 20.1 wae 1999
#> 4 21.1 wae 1999
#> 5 27.7 wae 1999
#> 6 27.5 wae 1999
op <- par(mfrow=c(2,2),pch=19)
### Four (of 16 possible) examples
with(subset(Herman,spec=="bbh" & yr==2003),hist(tl,main="Black Bullhead, 2003"))
with(subset(Herman,spec=="bkc" & yr==2001),hist(tl,main="Black Crappie, 2001"))
with(subset(Herman,spec=="yep" & yr==2003),hist(tl,main="Yellow Perch, 2003"))
with(subset(Herman,spec=="wae" & yr==1999),hist(tl,main="Walleye, 1999"))
par(op)
```