Community science reveals links between migration arrival timing advance, migration distance and wing shape

Area of Science:

• Ornithology
• Climate Change Ecology
• Animal Migration

Background:

• Global data indicate phenological shifts across taxa due to climate change.
• Avian migration arrival dates are advancing, influenced by evolution and behavioral flexibility.
• Flight efficiency may correlate with adaptability to changing environmental conditions during migration.

Purpose of the Study:

• To investigate the relationship between passerine morphology, flight efficiency, and shifts in spring arrival dates.
• To determine if traits like wing aspect ratio and migratory distance predict the magnitude of arrival date changes in response to climate warming.
• To identify bird species most vulnerable to climate change based on their migratory flexibility.

Main Methods:

• Utilized 18 years of eBird data to estimate mean arrival dates for 44 passerine species.
• Employed logistic and linear mixed-effects models to analyze changes in arrival timing.
• Used phylogenetic generalized least squares models to compare arrival shifts with morphological proxies for flight efficiency and migratory distance.

Main Results:

• Passerine species advanced arrival dates by an average of 0.120 days annually.
• 27 out of 44 species showed significant shifts to earlier arrival; two shifted later.
• Longer migration distances and higher wing aspect ratios were significantly associated with greater advancements in arrival dates.

Conclusions:

• Migratory flight efficiency and distance are key factors influencing avian arrival date shifts.
• Morphological traits can predict the magnitude of arrival date changes in response to climate change.
• These findings help identify species at higher risk due to inflexible migratory timing.