Comparison of parameters used in models of <i>B. pfeifferi</i>, <i>B. glabrata</i> and <i>B. alexandrina</i>.

<p>a) Juvenile development. Heat units gained per hour. Snails become adults and start producing eggs once they have gained 100 heat units. b) Egg production. Eggs per snail per hour. c) Egg development. Heat units gained per hour. Egg hatch once they have gained 100 heat units. d) Egg mortality rate per hour. e) Uninfected and prepatent snail mortality rate per hour. f) Parasite development within the snail. Heat units gained per hour. Snails become infectious once they have gained 100 heat units. Blue lines show parameters for <i>B. pfeifferi</i>, red for <i>B. glabrata</i>, green for <i>B. alexandrina</i>, and turquoise for both <i>B. pfeifferi</i> and <i>B. alexandrina</i>.