Tree sparrow (Passer montanus), which not swallowed the berries, but only drinking the juice from them, was the most clever species of birds I can observed this season on Elderberries (Sambucus nigra). Several pictures and the story in Belarusian are here: https://birdwatch.by/gallery/harrier/palyavy-verabey-i-sok-buziny Трошкі здымкаў і гісторыя палявога вераб’я, які выціскаў сок з ягад бузіны, па-беларуску тут: https://birdwatch.by/gallery/harrier/palyavy-verabey-i-sok-buziny