Combined effects of flow condition and parasitism on shoaling behaviour of female guppies Poecilia reticulata.

摘要: Group living in fish can provide benefits of protection from predators and some parasites, more efficient foraging for food, increased mating opportunities enhanced energetic benefit when swimming. For riverine species, shoaling behaviour be influenced by various environmental stressors, yet little is known how flow rate might influence the diseased shoals. In view increasingly unpredictable rates streams rivers, this study aimed to assess combined effect condition parasitism on a model species. Shoal size, shoal cohesion time spent female guppies Poecilia reticulata were compared infected with directly transmitted ectoparasite Gyrodactylus turnbulli under static conditions. Flow was an important factor influencing forming larger shoals absence flow. When member G. turnbulli, reduced, but magnitude dependent condition. both conditions, bigger formed than smaller counterparts. Future changes stream hydrology frequent flooding drought events will affect tendency fish. During high-flow events, may not able keep up mates therefore have higher risk predation. Additionally, these findings aquaria farmed species where increase reduce aggregation