Background: Until recently little was known about factors affecting reproductive parameters of the Turtle Dove(Streptopelia turtur) on intensively cultivated farmland in the Mediterranean area. In this study, the repr...Background: Until recently little was known about factors affecting reproductive parameters of the Turtle Dove(Streptopelia turtur) on intensively cultivated farmland in the Mediterranean area. In this study, the reproductive parameters of this game species were evaluated in relation to location, orchard type, laying period and nest position in central Morocco.Methods: A total of 317 nests were found and analyzed across five breeding seasons(2004–2008) in the Haouz and Tadla regions, over two major agro-ecosystems made up of olive and orange orchards. Nest position, laying period, clutch size and the number of chicks hatched and fledged per nest were determined on 120 study plots. I used Generalized Linear Models(GLMs) with a Poisson distribution and a log link function, including the logarithm of the number of eggs in each clutch as an offset to model the number of chicks hatched and fledged per nest.Results: Clutch-size was not affected by location, orchard type, laying period or nest position. The number of chicks hatched per nest differed between orchard types; they were greater in olive orchards(1.33 ± 0.06) than in orange ones(1.03 ± 0.08), whereas the number of chicks fledged per nest consistently differed with laying period and orchard type, which were higher in the early laying period(1.22 ± 0.07) than in the late period(0.93 ± 0.08) and higher in olive orchards(1.22 ± 0.06) than in orange orchards(0.90 ± 0.06). Neither location nor nest position were related to variation in the fledging success of the Turtle Dove.Conclusions: Olive orchards and the early laying period confer better nesting conditions than orange orchards and the late laying period. Although nest position could be different in each orchard type, it did not affect the breeding success of the Turtle Dove, suggesting that factors other than tree characteristics are influential. Further studies are needed to improve our understanding of the effects of anthropogenic disturbance, especially agricultural activities and hunting, on the productivity of Turtle Dove nests.展开更多
It is commonly admitted that the continuous development of human infrastructure(HI),resulting in natural habitat fragmentation,affects farmland birds by misleading their strategies of nest site selection.Here,we exami...It is commonly admitted that the continuous development of human infrastructure(HI),resulting in natural habitat fragmentation,affects farmland birds by misleading their strategies of nest site selection.Here,we examined how HI in agricultural landscape(AL)could be affecting nest habitat selection of Barbary partridge(BP;Alectoris barbara).A total of 160 BP nests were monitored during 4 years(2017,2018,2021,and 2022)in eight Moroccan agricultural zones.We used the generalized linear mixed models and variation partitioning methods to quantify the effects of AL and HI on BP nest occurrence.This occurrence increased with track density(within 300 m of sampled nests)and decreased with built-up area cover(50 m).Nest occurrence was also associated with the cover of agricultural areas(300 m),distances to the nearest agricultural area,the nearest human settlement,and the nearest track.However,the effect of these covariates depended on distance to the nearest paved road,being close to roads located far away from agricultural areas and tracks and near human settlements and tracks.Overall,our results highlighted a trend to nest close to HI when agricultural areas were relatively remote or less represented.For the effective conservation and management of theMoroccan BP populations,it is critical to keep human infrastructures at a level that allows formaintaining the relative dominance of the agricultural landscape.Further fragmentation of this landscape will impact the ability of this farmland species to select its nesting sites flexibly.展开更多
基金supported by the Forest Research CenterHigh Commission for Water,Forests and Desertification Control,Morocco
文摘Background: Until recently little was known about factors affecting reproductive parameters of the Turtle Dove(Streptopelia turtur) on intensively cultivated farmland in the Mediterranean area. In this study, the reproductive parameters of this game species were evaluated in relation to location, orchard type, laying period and nest position in central Morocco.Methods: A total of 317 nests were found and analyzed across five breeding seasons(2004–2008) in the Haouz and Tadla regions, over two major agro-ecosystems made up of olive and orange orchards. Nest position, laying period, clutch size and the number of chicks hatched and fledged per nest were determined on 120 study plots. I used Generalized Linear Models(GLMs) with a Poisson distribution and a log link function, including the logarithm of the number of eggs in each clutch as an offset to model the number of chicks hatched and fledged per nest.Results: Clutch-size was not affected by location, orchard type, laying period or nest position. The number of chicks hatched per nest differed between orchard types; they were greater in olive orchards(1.33 ± 0.06) than in orange ones(1.03 ± 0.08), whereas the number of chicks fledged per nest consistently differed with laying period and orchard type, which were higher in the early laying period(1.22 ± 0.07) than in the late period(0.93 ± 0.08) and higher in olive orchards(1.22 ± 0.06) than in orange orchards(0.90 ± 0.06). Neither location nor nest position were related to variation in the fledging success of the Turtle Dove.Conclusions: Olive orchards and the early laying period confer better nesting conditions than orange orchards and the late laying period. Although nest position could be different in each orchard type, it did not affect the breeding success of the Turtle Dove, suggesting that factors other than tree characteristics are influential. Further studies are needed to improve our understanding of the effects of anthropogenic disturbance, especially agricultural activities and hunting, on the productivity of Turtle Dove nests.
文摘It is commonly admitted that the continuous development of human infrastructure(HI),resulting in natural habitat fragmentation,affects farmland birds by misleading their strategies of nest site selection.Here,we examined how HI in agricultural landscape(AL)could be affecting nest habitat selection of Barbary partridge(BP;Alectoris barbara).A total of 160 BP nests were monitored during 4 years(2017,2018,2021,and 2022)in eight Moroccan agricultural zones.We used the generalized linear mixed models and variation partitioning methods to quantify the effects of AL and HI on BP nest occurrence.This occurrence increased with track density(within 300 m of sampled nests)and decreased with built-up area cover(50 m).Nest occurrence was also associated with the cover of agricultural areas(300 m),distances to the nearest agricultural area,the nearest human settlement,and the nearest track.However,the effect of these covariates depended on distance to the nearest paved road,being close to roads located far away from agricultural areas and tracks and near human settlements and tracks.Overall,our results highlighted a trend to nest close to HI when agricultural areas were relatively remote or less represented.For the effective conservation and management of theMoroccan BP populations,it is critical to keep human infrastructures at a level that allows formaintaining the relative dominance of the agricultural landscape.Further fragmentation of this landscape will impact the ability of this farmland species to select its nesting sites flexibly.
