Birds are among Earth's most important nutrient movers

Birds play a vital, often overlooked role in shaping Earth's chemistry by distributing essential nutrients across oceans, forests, and coral reefs, thereby sustaining life beyond their nests. Cornell researchers, alongside five other institutions, analyzed nearly 400 scientific papers to illustrate how birds transport nutrients from land, lakes, and seas via their waste and bodies, impacting soil, water chemistry, and plant/animal growth.

Lead author Dr. Ethan Duvall explains that birds act as efficient nutrient transporters, concentrating nutrients in their waste and depositing them into ecosystems as valuable resources for plants and organisms. Flight enables birds to cover vast distances and overcome barriers like oceans and mountains, while their high food consumption rates result in frequent nutrient intake and release.

Seabird colonies, in particular, deposit high concentrations of nutrients in small areas, fostering plant and algae growth and benefiting the organisms that consume these plants. When seabird colonies vanish, nutrient levels drop, leading to reduced plant and algae productivity, reef fish biomass, and coral reef resilience. Conversely, bird waste can aid in restoring plant communities.

This review sets out the magnitude and global scale of birds' nutrient transport role and suggests their potential in aiding ecosystem restoration. The study highlights that declining bird populations, with 45% of migratory bird species facing decline, could lead to less fertile ecosystems and diminished carbon sequestration capabilities.