This paper analyzes various saxophone works inspired by birds, including a dedicated section on Mashima's suite. It explores the musical language and techniques used to depict avian themes. About Toshio Mashima's Birds
Seagull for Alto Saxophone Ensemble | PDF | Performing Arts - Scribd
If you are looking for actual sheet music files to go along with your content:
"Birds" (Concerto for Alto Saxophone and Wind Orchestra) by Toshio Mashima