Fig. 1
The role of G. gobio as a decoy species. (A) Results of the infestation experiment: mean number of glochidia attached to fish five days after artificial infestation and mean number of successfully metamorphosed juveniles recovered over 40 days for P. phoxinus and G. gobio. Whiskers show observed ranges. (B) Spatial co-occurrence of U. crassus and G. gobio in Poland. Each square represents a 10 × 10 km grid cell. White squares indicate sites where U. crassus was recorded; light-blue squares denote cells where U. crassus and G. gobio occurred within < 5 km along the river; dark-blue squares mark cells where records of both species were within < 200 m. (C) Number of surveys in which the seven most frequent fish species occurred sympatrically with U. crassus (matched within < 200 m). (D) Mean percentage of these seven species in the catch across the same set of surveys.
