¿Qué pasaría si introdujera una grulla (¡otro tipo de pájaro!) En el hábitat (dime qué pasaría con la presa y las grazas azules)?

The rate that would change would be the  searching efficiency/attack rate. there are only two other rates in this model: the  growth rate of prey, and the  predator or consumer mortality rate.the  searching efficiency/attack rate is what indicates how effectively can a predator capture its prey whether in the searching process or actual capturing/attacking process. 

Blindness is your answer