Skip to content

Northern Wheatear Chicks Hatched Earlier in Eastern White Dunes and in Nests of Older Males

Male Northern Wheatear on Norderney, Germany
Research · Ecology

Northern wheatear (Oenanthe oenanthe) chicks on Norderney, Germany, hatched earlier the farther east on the island their nests were located, but this east–west pattern appeared only in white dunes. Researchers monitored 321 nests from 2021 to 2025 and used hatching date as an indirect measure of nest-site selection, based on the expectation that higher-quality sites are generally occupied earlier.

East–west gradient only in white dunes

Across all nests, the average hatching date was around 20 May. Habitat type itself and distance from nests to paths or streets showed no clear relationship with hatching date. Within white dunes, however, nests farther east hatched earlier. The modelled difference between the westernmost and easternmost nests was about ten days, and the same longitudinal pattern was not found in the other habitats.

The authors discuss two possible explanations for the white-dune pattern. Previous work found the highest rabbit densities in the central-eastern part of Norderney, and wheatears on the island nest in burrows made by introduced European rabbits (Oryctolagus cuniculus). The eastern white dunes may also be more stable because the island’s prevailing winds come from the west, potentially creating more favourable nesting conditions there. These explanations were not tested directly in the study.

Older males bred earlier in grey dunes

Male age mattered in a different habitat. In grey and vegetated dunes, chicks in nests of older males hatched about 2.5 days earlier than chicks in nests of second-calendar-year males. The authors conclude that hatching date can provide useful information about nest-site quality and selection on Norderney, but that the proxy is context-dependent and should be interpreted together with individual factors such as male age.

Sources and image credit

  1. Sandretti-Silva, G., Kirsten, L., Züst, Z., Peter, A., Reich, H., Ulber, J., & Schmaljohann, H. (2026). Hatching date in Northern Wheatears, as a proxy of nest site selection, shows a longitudinal gradient in the white dunes and occurs earlier in older males in the grey dunes on Norderney.Primary open-access research article first published 1 September 2026. Researchers monitored 321 Northern Wheatear nests on Norderney from 2021 to 2025. In white dunes, modelled hatching date differed by about ten days between the westernmost and easternmost nests; in grey and vegetated dunes, chicks in nests of older males hatched about 2.5 days earlier than chicks in nests of second-calendar-year males.

Image: Male Northern Wheatear on Norderney, Germany, 13 April 2024. Photo: Stephan Sprinz / Wikimedia Commons. CC BY 4.0. Representative photograph from the study island; not identified as a study bird. · CC BY 4.0 · Source

About this content: This story was produced with AI assistance within an editorial workflow developed by Wildlife Vagabond. Editorial responsibility remains with Wildlife Vagabond.How AI is used

Ecology

SPECIES IN THIS STORY

Species in this story

Northern Wheatear Oenanthe oenanthe Explore species

Independent research and conservation news archive

Did you find this information useful?

Wildlife Vagabond is independently built and maintained. Voluntary support helps cover source verification, hosting and continued work on research and conservation news.

Support Wildlife Vagabond

The news archive will remain freely available.