################################################
#                                              #
#         Fishery Sustainability Game          #
#         Ian J. Wang                          #
#         UC Berkeley                          #
#                                              #
################################################

## This is a game designed to be played over several class periods by groups of students.  
## To see the rules and an explanation of the game, view the FisherySustainabilityGame.ppt file.

countries <- c("Norway", "Iceland", "UK", "Denmark", "Netherlands")
r <- c(1.2, 0.8, 1.0, 1.5, 1.2)
K <- c(200, 220, 240, 100, 120)
N <- c(100, 60, 100, 40, 50) # Round 1 <- Update these values after each round (r and K stay the same)

## Fishing Phase ##
fishing.targets <- c(40, 33, 15, 38, 20) # Round 1 <- Enter the fishing targets for each team/country here.
off.targets <- runif(5, 0.9, 1.1) # Random deviation from Fishing Target by up to 10% (+/-)
fish.caught <- fishing.targets * off.targets
N <- N-fish.caught # Subtract fish caught from population size (N)

## Population Growth Phase ##
dN <- r*N*(1-(N/K)) # Based on logistic populatio growth: dN/dt = rN(1 - N/K)
N <- N+dN # Add new fish from population growth

## Dispersal Phase ##
dN[1] <- (0.04*N[3])-(0.05*N[1]) 
dN[2] <- (0.03*N[1])-(0.03*N[2])
dN[3] <- (0.03*N[2])+(0.01*N[4])+(0.02*N[5])-(0.04*N[3])
dN[4] <- (0.02*N[1])-(0.04*N[4])
dN[5] <- (0.03*N[4])-(0.02*N[5])
N <- N+dN # Add/substract fish from dispersal

## Fish Caught ##
fish.caught.1 <- c(NN, NN, NN, NN, NN) # Round 1 <- You can keep track of the number of fish each team has 
fish.caught.2 <- c(NN, NN, NN, NN, NN) # Round 2      caught in each round by entering them here.
fish.caught.3 <- c(NN, NN, NN, NN, NN) # Round 3
fish.caught.4 <- c(NN, NN, NN, NN, NN) # Round 4
fish.caught.5 <- c(NN, NN, NN, NN, NN) # Round 5
fish.caught.total <- fish.caught.1 + fish.caught.2 + fish.caught.3 + fish.caught.4 + fish.caught.5