Pathogenic bacteria and timing of laying

Area of Science:

• Ecology
• Microbiology
• Ornithology

Background:

• Pathogenic bacteria pose a significant threat to organism viability.
• Seasonal environments may favor earlier reproduction to mitigate bacterial exposure.
• Predators, like goshawks, face heightened risks from pathogenic microorganisms in prey.

Purpose of the Study:

• To test the hypothesis that earlier goshawk reproduction reduces exposure to pathogenic bacteria.
• To investigate the relationship between breeding phenology, bacterial load, and reproductive success in goshawks (Accipiter gentilis).

Main Methods:

• Bacterial sampling was conducted on adult and nestling goshawks.
• Data on laying dates, capture success, and reproductive outcomes (hatching/fledging failure) were collected.
• Statistical analyses examined associations between bacterial abundance (Staphylococcus), breeding timing, and goshawk fitness.

Main Results:

• Adult goshawks with higher Staphylococcus loads were captured more easily, indicating delayed laying.
• Later-laying goshawks had nestlings with increased Staphylococcus on beaks and claws.
• Higher Staphylococcus abundance correlated with increased hatching and fledging failure, independent of other factors.

Conclusions:

• Reproductive timing in goshawks appears influenced by pathogenic bacterial loads.
• Early breeding, associated with lower bacterial exposure, leads to greater reproductive output.
• Pathogenic bacteria may play a role in selecting for optimal breeding phenology in seasonal environments.