BIO 3302 Lecture Notes - Lecture 18: Interspecific Competition, Resource Consumption, Cost Overrun

• School: University of Ottawa
• Department: Biology
• Course: BIO 3302
• Professor: Kathleen Gilmour

Document Summary

A few figures from a study that we found that shows the variation in rates of aggression (cid:894)(cid:373)easured (cid:271)y the (cid:374)u(cid:373)(cid:271)er of e(cid:448)e(cid:374)ts per hour(cid:895) for mo(cid:374)tagu"s a(cid:374)d he(cid:374) harriers duri(cid:374)g 3 parts of the (cid:271)reedi(cid:374)g seaso(cid:374). Mo(cid:374)tagu"s harrier is sho(cid:449)(cid:374) i(cid:374) the (cid:271)la(cid:272)k (cid:271)ar, he(cid:374) i(cid:374) (cid:449)hite: shows intraspecific aggression. Generally, montagus have a higher rate of aggression than hens. Aggression is highest during the prelaying period and decreases during incubation and nestling. Mo(cid:374)tagu"s harrier, the aggressio(cid:374) rate to(cid:449)ards he(cid:374) harriers was relatively constant throughout the season. In contrast, hen harriers showed low rates of aggression in the prelaying period with a gradual increase after that. Mo(cid:374)tagu"s a(cid:374)d he(cid:374) share similar habitats and food resources. Interspecific competition for food increases and peaks at nestling because of the increase in population size when chicks are hatched: intrasexual and specific aggression, the rate of aggression decreased after prelaying in both species.