You can communicate with birds. You can have a single, harmless bird companion that follows you around and follows your commands.

You have advantage to open locks while singing to them. You can also cause a lock in 6 to snap shut with a song.

You can communicate with roots in vague emotions, though their senses are limited. Once per day, you find 1d4 rations worth of edible roots.

Your whistling can tie, untie, or unravel string, laces, garments, etc. You can cause loose threads/strings to move as you direct, though this does not increase their strength.

You can touch wooden objects to learn the name of their creator or the last person to touch it. You also learn the most recent strong emotion it would have absorbed from sentient creatures.

You can instantly ferment a pint of sweet liquid into alcohol (delicious to mosslings, horrific to others). You can learn another's name by sipping from a drink they already drank from.