What Are The Potential Impacts Of Increased Ice-albedo Feedback On The Migratory Patterns And Habitat Selection Of Western Arctic Caribou, Specifically In Relation To The Timing Of Vegetation Green-up In The Brooks Range And The Subsequent Effects On Their Nutritional Condition And Population Dynamics?

The potential impacts of increased ice-albedo feedback on Western Arctic caribou can be understood through several interconnected factors:

1. Ice-Albedo Feedback and Arctic Warming: Increased ice-albedo feedback accelerates Arctic warming by reducing the Earth's reflectivity, leading to more absorbed sunlight and a faster melting of ice. This warming affects the timing of vegetation green-up in the Brooks Range.

2. Timing of Vegetation Green-Up: Warmer temperatures cause earlier spring green-up. Caribou rely on synchronizing their migration with this period to access nutritious forage. A mismatch could occur if caribou arrive after the peak, leading to reduced food quality and availability.

3. Nutritional Condition and Health: Mismatched timing can result in poorer nutritional condition, particularly affecting calves and pregnant females. This can lead to lower survival rates and reproductive success.

4. Habitat Changes: Thawing permafrost alters landscapes, creating obstacles like thermokarst lakes. These changes can fragment habitats and make migration routes more challenging, increasing energy expenditure for caribou.

5. Population Dynamics: Reduced survival and reproduction can lead to population decline, affecting ecosystem balance and species dependent on caribou, such as predators.

6. Additional Stressors: Warmer conditions may increase insect-related stress and competition from other herbivores, further pressuring caribou populations.

In summary, increased ice-albedo feedback may disrupt caribou migration timing, leading to nutritional stress, habitat challenges, and population decline, threatening the sustainability of Western Arctic caribou and their ecosystem.