Abstract
Capsule:Cereal harvesting creates high-quality but ephemeral foraging habitats for invertebrate predators.
Aims: To investigate how cereal harvesting affects foraging decisions and hunting success of Lesser Kestrels.
Methods: Habitat selection in response to changing availability of cereal fields (as patches being harvested are turned into stubble) was assessed by transects around colonies to count foraging birds. Focal observations of foraging kestrels were performed to assess hunting success and intake rate before and after harvesting. We performed transects to count Orthoptera to evaluate the impact of cereal cutting on prey abundance.
Results: Harvesting impacted prey accessibility due to a temporary flush of prey, which resulted in a significant reduction in foraging time and an increase in the intake rate of kestrels. Accordingly, patches being harvested became the most preferred habitat. Nonetheless, harvesting likely caused high orthopteran mortality and dispersal leading to a gradual decline in prey abundance in stubbles. Lower prey abundance increased foraging time and reduced intake rate, and stubbles became avoided by foraging individuals.
Conclusion: Although harvesting significantly increases foraging opportunities for Lesser Kestrels through intake rate maximization, patches being harvested represent an ephemeral high-quality habitat and its benefits are relatively short-lived as cereals are converted into low-quality stubbles.
Aims: To investigate how cereal harvesting affects foraging decisions and hunting success of Lesser Kestrels.
Methods: Habitat selection in response to changing availability of cereal fields (as patches being harvested are turned into stubble) was assessed by transects around colonies to count foraging birds. Focal observations of foraging kestrels were performed to assess hunting success and intake rate before and after harvesting. We performed transects to count Orthoptera to evaluate the impact of cereal cutting on prey abundance.
Results: Harvesting impacted prey accessibility due to a temporary flush of prey, which resulted in a significant reduction in foraging time and an increase in the intake rate of kestrels. Accordingly, patches being harvested became the most preferred habitat. Nonetheless, harvesting likely caused high orthopteran mortality and dispersal leading to a gradual decline in prey abundance in stubbles. Lower prey abundance increased foraging time and reduced intake rate, and stubbles became avoided by foraging individuals.
Conclusion: Although harvesting significantly increases foraging opportunities for Lesser Kestrels through intake rate maximization, patches being harvested represent an ephemeral high-quality habitat and its benefits are relatively short-lived as cereals are converted into low-quality stubbles.
Original language | English |
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Pages (from-to) | 447-456 |
Number of pages | 10 |
Journal | Bird Study |
Volume | 61 |
Issue number | 4 |
Early online date | 12 Sep 2014 |
DOIs | |
Publication status | Published - 2014 |