Evangelos Chatzinikos

Aerial Hunting Behaviour of the Lesser Kestrel Falco naumanni During the Breeding Season in Thessaly (Greece)

Abstract. We studied the foraging behaviour of Lesser Kestrels in agricultural habitats during the breeding season of 2000. The birds spent more time hunting in flight than perched. During 398 min. of observed aerial hunting, they spent 23.7% hovering, 14.4% hanging, 14.0% flapping, 41.2% gliding, and 6.7% soaring. The time spent on each type of aerial hunting behaviour depended on factors like breeding stage, time of day, wind speed, number of strikes, number of successful strikes, and the time spent hunting. The strike rate was 0.38 per min., the capture rate 0.10 per min. The capture rate depended on the type of hunting behaviour preceding the attack and was highest after the birds had been hovering.

Diet Composition and Feeding Strategies of the Stone Marten (Martes foina) in a Typical Mediterranean Ecosystem

Stone martens (Martes foina) are documented as generalist throughout their distributional range whose diet composition is affected by food availability. We tested if this occurs and what feeding strategies it follows in a typical Mediterranean ecosystem in Central Greece by analysing contents from 106 stomachs, seasonally collected from three different habitats during 2003–2006. Seasonal variation in diet and feeding strategies was evident and linked to seasonal nutritional requirements, but possibly imposed by strong interference competition and intraguild predation. Fleshy fruits and arthropods predominated in the diet, but also mammals and birds were frequently consumed. An overall low dietary niche breadth (B A = 0.128) indicated a fruit specialization tendency. A generalised diet occurred in spring with high individual specialisation, whereas more animal-type prey was consumed than fruits. A population specialization towards fruits was indicated during summer and autumn, whereas insects were consumed occasionally by males. In those seasons it switched to more clumped food types such as fruits and insects. In winter it selectively exploited both adult and larvae insects and partially fruits overwinter on plants. The tendency to consume particular prey items seasonally reflected both the population specialist behaviour and the individual flexibility preyed on different food resources.

Home range and foraging habitat selection by breeding lesser kestrels (Falco naumanni) in Greece

Home range size and foraging habitat use in breeding lesser kestrels (Falco naumanni), a bird species of conservation concern, were investigated during the breeding season of the species in 2008 in an intensively cultivated area of central Greece, using radio-tracking. Grasshopper (the main prey) densities were measured at the most important habitats (cotton, cereals, grasslands and margins). Home ranges were not significantly different between sexes either as overall means or during incubation and nestling periods. Movements of both sexes were non-random during incubation but random during the nestling period. Habitats used by males during incubation ranked as: margins > other > cotton > corn > cereals and during nestling period as: cereals > margins > grasslands > corn > cotton. Female habitat use greatly differed ranking as cereals > cotton > grasslands during incubation and as grassland > cotton > corn > cereals > margins during nestling period. Female habitat use seemed to be in disagreement with the conditions generally favouring prey availability, probably for reasons associated with low and uniform distribution of grasshopper densities over the habitats.

Assessment of Nestling Diet and Provisioning Rate by Two Methods in the Lesser Kestrel Falco naumanni

Abstract. Nowadays the use of remote photography systems is very popular for diet assessment. Despite the popularity, there is a greater need for evaluation of these systems against traditional methods of diet assessment, such as direct visual observation. The diet of Lesser Kestrel nestlings and adult provisioning rate were assessed using cameras and direct observations at four nests with various brood sizes during the breeding season in 2013. The study was conducted in an intensively cultivated area that belongs to a Special Protected Area of the Natura 2000 network in central Greece. Diet composition (prey type and size) was not affected by the recording method, the sex of adults, the brood size, the period of the day or the age of nestlings. Tettigoniidae was the most frequent prey delivered by adults. Our results from both methods showed that males delivered more prey items than females, supporting the general consensus of reversed sexual dimorphism for the Lesser Kestrel. The provisioning rate was not significantly related to brood size, but it was affected by the method of observation, parent sex and the interaction of method and nestling age. According to the direct observations, provisioning rates increased as nestlings grew up, while they decreased based on camera information. Higher provisioning rates recorded in direct observations at later nestling stages, can be explained by higher food requirements of nestlings. The decrease in provisioning rate with nestling age was mostly affected by the camera function, as a result of digital limitations, nest type and Lesser Kestrels behavior.