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Selective Pressures Influence a Grow Fast, Fly Young Strategy for Black Skimmer Populations in the Peruvian Amazon
Katharine S Goodenough1,2, Torbjørn Haugaasen3, Eli S Bridge2
1School of Biological Sciences, Dodge Family College of Arts and Science University of Oklahoma Norman Oklahoma USA.
Ecology and Evolution
|May 20, 2026
Summary
Black Skimmers in Peru exhibit faster chick development due to high food availability and flooding risks. This adaptation shortens their vulnerable period, differing from coastal populations.
Area of Science:
- Ornithology
- Ecology
- Evolutionary Biology
Background:
- Black Skimmers (Rynchops niger) typically nest coastally.
- South American populations nest in freshwater river tributaries, facing unique predation and flooding threats.
Purpose of the Study:
- Compare life history traits of Peruvian Black Skimmers with other American populations.
- Investigate adaptations to freshwater nesting environments.
Main Methods:
- Monitored Black Skimmers in Manu National Park, Peru, over two breeding seasons.
- Compared life history traits (clutch size, survival, hatching success, incubation, provisioning, fledging) with conspecific populations.
Main Results:
- Peruvian Black Skimmers had short incubation bouts and high provisioning rates.
- Chicks fledged ~10 days earlier than North American populations.
- Flooding caused 41%-61% of nest failures, impacting early development.
Conclusions:
- Initial reproductive investment is conserved across Black Skimmer populations.
- Freshwater nesting selects for rapid chick growth to minimize exposure to mortality risks like flooding.
- Rapid development is an adaptation to exploit abundant resources and reduce offspring vulnerability.
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