Surviving at high elevations: an inter- and intra-specific analysis in a mountain bird community

Area of Science:

• * Ornithology
• * Evolutionary Ecology
• * Wildlife Biology

Background:

• * Elevation is a significant factor influencing bird survival and life history traits.
• * Previous research has not fully explored how life-history variation along elevational gradients differs among and within species.
• * Understanding these variations is crucial for predicting species' responses to environmental changes.

Purpose of the Study:

• * To investigate how average adult survival of open-habitat passerine species correlates with their elevational distribution.
• * To analyze intra-specific variation in adult survival in relation to elevation.
• * To compare elevational survival patterns between species and within species.

Main Methods:

• * Analyzed adult survival data for 25 sympatric open-habitat passerine species.
• * Employed capture-recapture analyses to estimate intra-specific adult survival variation.
• * Focused on two mountainous species: Water pipit (Anthus spinoletta) and Northern wheatear (Oenanthe oenanthe) in NW Spain.

Main Results:

• * Inter-specifically, species at higher elevations exhibited higher adult survival rates.
• * Intra-specifically, the Water pipit showed decreased survival and increased transient individuals at higher elevations.
• * No significant elevational survival relationship was observed in the Northern wheatear.

Conclusions:

• * Higher elevation species may allocate more resources to self-maintenance, enabling persistence in harsh alpine environments.
• * Intra-specific analyses indicate potential costs of high-elevation living, as seen in the Water pipit.
• * Species may persist in high-elevation areas with high mortality by enhancing self-maintenance and prospecting behaviors.