Do Arctic breeding geese track or overtake a green wave during spring migration?

Area of Science:

• Ecology
• Animal Migration
• Phenology

Background:

• Arctic breeding requires efficient resource utilization due to a short time window.
• Capital breeding strategies and migration timing are crucial for reproductive success in geese.
• The green wave hypothesis suggests migratory herbivores follow plant phenology.

Purpose of the Study:

• To test the green wave hypothesis in Barnacle Geese migration.
• To investigate the relationship between satellite-derived plant phenology and goose stopover behavior.
• To determine if geese track spring onset or peak nutrient biomass during their journey.

Main Methods:

• Linking satellite-derived onset of spring and peak nutrient biomass data with individual Barnacle Goose stopover data.
• Analyzing migration schedules in relation to environmental cues.
• Estimating plant development stages using remote sensing.

Main Results:

• Barnacle Geese did not track the onset of spring or peak nutrient biomass.
• Geese arrived at their southernmost stopover site near the peak nutrient biomass.
• They gradually overtook the green wave to align breeding site arrival with the local onset of spring.

Conclusions:

• Barnacle Geese employ a partial capital breeding strategy, optimizing arrival for breeding success.
• Migration timing is finely tuned to ensure goslings hatch at the peak of nutrient availability.
• The study provides a novel method for assessing migratory herbivore strategies.