An award in your field and specialty area is one of the most important honors. Many people forget to send a thank you card or note to the awardee. I really appreciate you recognizing me. Many people don’t take the time to send thank you notes/cards, so by doing so you are building your reputation as a leader.
Whether it’s a one-liner or a longer letter, expressing sincere appreciation would be nice. I always give my best and expect nothing in return, but your thoughtfulness means a lot to me.