Is their a difference in draw length between a long bow and a recurve
Because of less shelf depth and general lack of a locator depression in the grip its a little harder to apply the AMO rule to classic longbows like the Hill style and many r/d's without some confusion, so your draw may 'appear' shorter than on a recurve with a deep locator and deep shelf. 'Per the specific bow' it could be said that you have a shorter draw on a straight or shallow grip/ shallow shelf Hill vs. say a Bear Super K as an example, but if you thought about it biomechanically and did some measuring of the end of your arrow vs your bow hand vs the point where the string touches your anchor point at full draw you'd notice the difference is minimal to none bow to bow. How a given bow accepts your draw length is another thing entirely and depends on the bow length and design.
It makes a difference for me, shooting the longbow with a "low wrist" position and the recurve from a "high wrist" position. Another thing that shortened my draw was breaking the radius in my left arm just below the wrist a few years ago. The radius is now nearly 1/2 inch shorter than it used to be.
It all depends on the grip and how much flex is left in the bow arm with a straight gripped bow, another part is stance changes and head positions. From target form with a straight bow arm to a Hill style form and bow arm for me, it is an inch and a half. Everyone will vary, your draw length is what it is either way, targeting a draw length by what happens with another person is not the best way to measure your own.
I find that my draw changes anywhere from 28.5-31" depending what bow I'm using and shooting position, anywhere from classic target stance to on my knees fully facing what I'm shooting.
To find my average draw length, I just draw and mark an arrow at the back of the bow. Add an inch for arrow length. I use to be seriously hung up on making sure I drew the EXACT same length every shot, too much hassle, not much fun. I pretty much never "target" shoot anymore. All hunting scenarios only. Like stumping and squrrels hunting. I keep a 8" group out too about 25 paces. Great for hunting.
I lost almost an in going from a Widow Recurve to a Big Jims Buffalo bow