For those wondering, some of these birds can fly over 5 miles high. From 5 miles above sea level, the distance to horizon is 200 miles. From 5 miles high, you could see the tip of mount Everest above the horizon from 410 miles. Great snipes can fly thousands of miles in one continuous 60-90 hour flight.
https://www.inverse.com/science/migratory-birds-flying-ocean