More specifically, it was the Toshio Mashima: Complete Birds digital folio.
Birds (often performed as a suite or a standalone tone poem depending on the edition) is exactly what the title suggests: an attempt to translate the flight, calls, and freedom of avian life into musical notation. toshio mashima birds pdf exclusive
Genuine "exclusive" PDFs are typically restricted by copyright, but you can find official materials and performances through these channels: More specifically, it was the Toshio Mashima: Complete
Toshio Mashima's Birds (2008) is a notable three-movement concerto for alto saxophone and wind ensemble, featuring movements centered on the swallow, seagull, and phoenix. The piece emphasizes emotional, impressionistic soundscapes rather than direct imitation of bird calls, demanding high technical proficiency from the soloist. Seagull (~5:48):
Characterised by agile, darting melodic lines that evoke the quick movements of a swallow. II. Seagull (~5:48):