Territoriality and variation in home range size through the entire annual range of migratory great spotted cuckoos (Clamator glandarius)

Abstract

Variation in home range size throughout the year and its causes are not well understood yet. Migratory brood parasites offer a unique opportunity to incorporate this spatio-temporal dimension into the study of the factors regulating home range dynamics. Using satellite transmitters, we tracked sixteen migratory great spotted cuckoos ( Clamator glandarius ) of both sexes for up to three years. We constructed home ranges in all major staging areas, from the Spanish breeding areas to the African wintering grounds, analyzed their temporal and geographical variation and investigated their main potential determinants (e.g. food and host availability). We found that home ranges were significantly larger in the breeding area compared to non-breeding areas. Using NDVI as a proxy for food availability, we showed that breeding area home ranges have significantly lower food availability per km 2 than home ranges elsewhere which could explain why cuckoos use alternative areas with higher food availability before initiating migration. We also found some evidence for sex differences. Additionally, we found no indications of territoriality in this species, providing novel information into the current debate on brood parasite territoriality. Overall, food availability seems to be an important factor regulating home range dynamics and influencing migratory patterns throughout the year in great spotted cuckoos.

Cheating Cheaters: Social Monogamy but Genetic Polygamy in a Brood Parasite

“…Early reports by Arias de Reyna et al (1987), based on recorded movements of unbanded individuals, categorised this species as territorial in the Sierra morena (southern Spain), whereas a more recent genetic study (martínez et al, 1998) showed a large overlap of female laying ranges at Guadix (southern Spain). Rühmann et al (2019) also found no territoriality of GPS-tagged individuals during both the breeding and non-breeding seasons.…”

Daily activity, diet and habitat of Bali myna (Leucopsar rothschildi) in Nusa Penida, Bali, Indonesia

“…Godet et al (2018) also proved that a wider home range indicates poor habitat quality, so birds must forage into a wider area, meanwhile daily movement patterns differ between habitats, caused by differences in spatial distribution of resources (Rechetelo et al 2016). Food availability seems to be an important factor regulating home range dynamics throughout the year (Rühmann et al 2019). The home range size can also be influenced by competition (Gregory 2017).…”

Where did the finch go? Insights from radio telemetry of the medium ground finch (Geospiza fortis)

“…Home range size and habitat selection patterns often vary during the annual cycle (Rühmann et al, 2019 ; Stanley et al, 2021 ; Wiktander et al, 2001 ). We found that the smallest (7.58 ha) and the largest (29.09 ha) home range size corresponded to an egg‐laying bird (JP4645; Tables 1 and 2 ) and a chick‐rearing bird (KGSK2033), which is consistent with general expectations for birds (e.g., Kolts & McRae, 2017 ; Zurell et al, 2018 ).…”