######################
# Additive mortality #
######################
h=seq(0,1,.05)
s0=0.6
Sa=s0*(1-h)
plot(h,Sa,lty=1,type='l',col='red',ylim=c(0,1),xlim=c(0,1),
     ylab='Survival Rate')


##########################
# Compensatory mortality #
##########################

### C=1-s0 ###
# Set C to be (1-s0)
C=1-s0  

# Conditional survival rate based on whether
#  harvest rate (h) is greater than C or not 
Sc=ifelse (h > C, ((1-h)/(1-C))*s0, s0+0*h)

# Plot compensatory model
points(h,Sc,lty=2,type='l',col='red')
abline(v=C,lty=3,col='red')

### C < 1-s0 ###
# Set C to be lower than (1-s0)
C=1-s0-(0.5*(1-s0))

# Conditional survival rate based on whether
#  harvest rate (h) is greater than C or not 
Sc=ifelse (h > C, ((1-h)/(1-C))*s0, s0+0*h)

# Plot compensatory model
points(h,Sc,lty=2,type='l',col='green')
abline(v=C,lty=3,col='green')