After the attack on their tree, the leaders of Dusk's colony decide it is best to travel to the mainland, where they can enlist the help of other beast to try and prevent Carnassial from harming other creatures. The colony then proceeds the next day to the coast, guided by Dusk (whose speed and agility were extremely useful). His job was to warm of the colony of any danger ahead. At the coast, the elders try to figure out how to glide to the mainland, but are weary as the wind is against them. They don't have a choice though, but have hope as Dusk suggests riding the thermals above the water to cross. Dusk tries this himself, but sees a felid who appears to have gone back to warn the others.
In the next chapter, the chiropter colony attempts the crossing, while riding the thermals. Many struggle, but eventually it works. They barely escaped the felids as they took off. As the chiropters glide over the crossing on the thermals, the birds arrive, and attempt to use their wings to disorient and slow the chiropters down, while shouting insults such as "egg-eaters" at the chiropters. The entire colony barely makes it across the clearing.
After reading these chapters, I realized once again another connect in this story to Maslow's Hierarchy of Needs. The chiropters the previous night were driven out of their beloved sequoia tree, and no longer had a suitable shelter, one of their primary needs. Since they had not shelter, they all decided that they must go to the mainland, and find a place safe enough to shelter them, so they could once again have safety and security, one of the primary needs of life.