Nesting success and productivity of the Common Barn-owl Tyto alba: results from a nest box installation and long-term breeding monitoring program in Southern Hungary

Abstract

In this study, the results of a long-term nest box installation program of the Common Barn-owl Tyto alba (Scopoli, 1769) in Southern Hungary were evaluated, which program was conducted during a 24-year period (1995–2018). The percentages of occupied nest boxes ranged from 9.72 to 73.44% in the first breeding periods while this varied between 0 and 41.46% in the case of repeated clutches in the same nest boxes with second broods. A total of 1,265 breeding attempts were recorded including 1,020 (80.63%) in the first and 245 (19.36%) in the second breeding periods, from which a total of 210 (16.6%) clutches did not produce any fledglings. The modal clutch size was 7 eggs in both first and second annual clutches. However, the value of productivity was higher in the case of larger clutch sizes and we found significant linear relationship between initial clutch size and fledgling production per nesting attempt in both breeding periods. Significant variation of reproductive parameters was observed among the years. The proportion of egg loss showed significant decline, while the change of hatching success and the variation of annual productivity showed significant slight positive linear trend during the 24 years. Our results suggested that despite the outlier values of reproduction characteristics in the extreme years with negative effect, a relatively stable Common Barn-owl population can be maintained by the placement of nest boxes in the investigated region.

Multi‐year nest box occupancy and short‐term resilience to wildfire disturbance by barn owls in a vineyard agroecosystem

“…Specifically, Botta’s pocket gophers ( Thomomys bottae ) and California voles ( Microtus californicus ), important pest species and prey of barn owls, are most likely to be found in grassland and can reach high densities in this land cover type (Huntly and Inouye 1988, Fehmi and Bartolome 2002, Ordeñana et al 2012). Nestling survival may be affected by nest box material, direction, and other factors that influence temperature (Charter et al 2010, 2017, Bank et al 2019). Future work should examine whether reproductive success is associated with the land cover and nest box variables we have found to affect occupancy and persistence.…”

Variation in the diet and breeding biology of the Common Barn-owl (Tyto alba) in a demographic cycle of Common Vole (Microtus arvalis) between two outbreaks×

“…For each of the selected Barn Owl pairs, the reproductive output was evaluated by six parameters: 1) clutch size (number of eggs in a clutch), 2) brood size at hatching, 3) brood size at fledging, 4) hatching success (the percentage of eggs that hatched within each clutch), 5) fledging success (the percentage of young that fledged from each brood), and 6) reproductive success (the percentage of fledged young per eggs from each successful nest) (see Bank et al 2019).…”

“…Clutch size is one of the most important life history traits of birds (Lack 1947, Price & Liou 1989, which has been studied and discussed in the Common Barn-owl's breeding biology literature from different aspects, such as the comparison of first and second clutches (Marti 1994, Martínez & López 1999, Frey et al 2011, Bank et al 2019, seasonal and annual variations of clutch size (Marti 1994, Martínez & López 1999, Toms et al 2001, Roulin 2002, and its relation to main prey abundance (Taylor 1994, Charter et al 2015, Pavluvčík et al 2015. In our regression analysis and modelling, we found that primarily the proportion of the Common Vole as main prey affected the variation of clutch size, where the independent main effect of this rodent was the most prevailing.…”

“…In the present study, data on the reproductive output come from the long-term monitoring program of nest box breeding Common Barn-owls. The continuous survey of the reproductive parameters has been conducted since the mid-90s in our studied region by the Baranya County Group of BirdLife Hungary during the last 25 years (Bank et al 2019). Detailed data of nest box installation and control protocol can be found in Bank et al (2019).…”

“…The continuous survey of the reproductive parameters has been conducted since the mid-90s in our studied region by the Baranya County Group of BirdLife Hungary during the last 25 years (Bank et al 2019). Detailed data of nest box installation and control protocol can be found in Bank et al (2019). Pellet collections and diet analyses were also conducted parallel to the breeding biology monitoring.…”