frair (version 0.5.100)

bythotrephes: Bythotrephes Functional Response Data

Description

Functional response dataset for Bythotrephes spp. (water fleas) preying on prey items of different sizes.

Usage

data(bythotrephes)

Format

A dataframe with the following structure:

density:	An integer. The initial density of prey	eaten:	An integer. The number of prey eaten
alive:	An integer. The number of prey left alive	size:	A factor with levels 'small', 'medium' and 'large'. The size of prey items.

Details

Bythotrephes spp. (water fleas) preying on prey items of different sizes. Prey were not replaced during the experiment and total experimental time was 12 hours. Provides a example dataset for type-III and flexible exponent models.

Examples

data(bythotrephes)
str(bythotrephes) 

with(bythotrephes, 
	plot(density, eaten, type='n', 
	xlab='Density', ylab='No. Prey Eaten'))
with(bythotrephes[bythotrephes$size=='large',], 
	points(density-0.2, eaten, pch=20, col=rgb(0.5,0,0,0.4)))
with(bythotrephes[bythotrephes$size=='medium',], 
	points(density, eaten, pch=20, col=rgb(0,0.5,0,0.4)))
with(bythotrephes[bythotrephes$size=='small',], 
	points(density+0.2, eaten, pch=20, col=rgb(0,0,0.5,0.4)))

legend(1,12, c('Large', 'Medium', 'Small'), pch=20, bty = 'n', 
    col=c(rgb(0.5,0,0), rgb(0,0.5,0), rgb(0,0,0.5)))