Main content area

Timing of breeding, habitat preference and reproductive success of marsh harriers (Circus aeruginosus)

Němečková, Iva, Mrlík, Vojtěch, Drozd, Pavel
Biologia 2008 v.63 no.2 pp. 261-265
Circus aeruginosus, Phragmites australis, Typha, birds, breeding, females, habitat preferences, habitats, nesting, nests, progeny, reproductive performance, reproductive success, vegetation cover
During 2002–2005 we analyzed Lack’s Hypothesis about the timing of the breeding of marsh harriers (Circus aeruginosus) in the Poodří to the breeding period and preference of heterogeneous habitat. An analysis of 43 nests revealed quantitative differences. Birds which started breeding earlier, reached significantly higher reproductive success than later breeding birds regardless of nesting habitat (P = 0.003, n nests = 43). Even when the birds invested into their offspring the same way, their breeding success was not always the same. When the females nested in the common reed (Phragmites communis), they reached higher reproductive output than females nesting in cattail (Typha sp.) (P = 0.01, n cattail = 18, n common reed = 25). The habitat of the common reed is characterized by higher and denser vegetation cover than cattail vegetation (P < 0.001, n measurements = 174 for both variables).