Zip ties are a great way to identify birds (leg bands). This kit has lots of colors and several sizes.
https://www.amazon.com/Nylon-Cable-Tie-Kit-Assorted/dp/B071SLNHZ3/ref=sr_1_10?keywords=colored+zip+ties&qid=1668489635&sr=8-10&th=1
https://www.amazon.com/Nylon-Cable-Tie-Kit-Assorted/dp/B071SLNHZ3/ref=sr_1_10?keywords=colored+zip+ties&qid=1668489635&sr=8-10&th=1