Habitat utilization and prey selection of the kestrelFalco tinnunculusin relation to small mammal abundance

Abstract

The study examined habitat utilization and prey selection by the kestrel Falco tinnunculus in an area of cultivated farmland in Italy, along with field estimates of small mammal abundance. Kestrel males were radiotagged and ranging behaviour and diet were recorded. Kestrels actively selected grasslands both during flight and perching hunting, and most predations were registered in this habitat. The occurrence of small mammals in the diet was significantly different from what was estimated from trapping, indicating that kestrels behaved as selective predators, since microtines were eaten in a greater proportion than their abundance. Microtus savii was preferred more than the common vole Microtus arvalis, whereas soricids were negatively selected. Nevertheless, common voles represented the main component of the kestrels' food niche. Reproductive success was correlated with small mammal availability. This study revealed that the high density of kestrels within the study area is supported by steady grassland management.

Can temporal covariation and autocorrelation in demographic rates affect population dynamics in a raptor species?

“…The index of vole abundance accounted for 86% of the annual variation in productivity suggesting that vole abundance is the main determinant of kestrel breeding success. This result is consistent with previous studies on kestrels showing that voles are the preferred prey and that vole abundance correlates positively with breeding success (Casagrande et al, ; Fargallo et al, ; Korpimäki, ). This strong relationship is also consistent with the food availability hypothesis to explain the pattern of covariation observed in this study.…”

“…Although kestrels are opportunistic foragers, voles (Microtus sp.) are generally the most important prey (Casagrande, Nieder, Minin, Fata, & Csermely, 2008;Korpimäki, 1986;Village, 1982). The kestrel is a nonobligate hole nester.…”

Presence of Cuckoo reliably indicates high bird diversity: A case study in a farmland area

“…From a co-evolutionary perspective, our findings are consistent with the hypothesis that the long-term ebb and flow of co-evolutionary selection might be an important source of ecological dynamics increasing biodiversity in biological communities (Thompson and Cunningham, 2002). On the other hand, the reduced ability of predators to predict local biodiversity of birds may be connected to diet because voles and other small mammals (not only birds) constitute an important component of the diet of Buzzard and Kestrel (Casagrande et al, 2008;Mañosa, 2003;Redpath et al, 2001;Rooney and Montgomery, 2013;Slagsvold et al, 2010).…”

Reproductive performance ofEurasianKestrelFalco tinnunculusin an agricultural landscape with a mosaic of land uses

“…Grass cutting for dairy cow feeding is widespread in this area, which is a PDO (protected designation of origin) for the production of Parmesan cheese (for further details see Casagrande et al . ). Thus, these three land uses represent a gradient of land management.…”