“What do you call a crocodile that likes to bowl?”/“An alley gator.”

A bowling alligator pun is:
 
Q: What do you call an alligator who goes bowling?
A: An alley gator.
 
The joke has been cited in print since at least 1980.
 
   
24 July 1980, Lexington (KY) Herald, A Page Just For Kids, pg. C-4, col. 5:
What do you call an alligator who goes bowling? An alley gator!—Paul Ladwig, 9. Lexington.
 
21 April 1985, Newsday (Long Island, NY), Kidsday, pg. 47, col 3:
What do you call an alligator who goes bowling?
An alley gator.
—David Fischer, Bayside
     
17 August 1986, The Plain Dealer (Cleveland, OH), Comic Section, pg. ?, col. 3:
What do you call an alligator that bowls?
An Alley Gator.
 
Google Books
Animal Jokes & Riddles
By Jeffrey S. Nelsen
New York, NY: Checkerboard Press
1991
Pg. 4:
What’s big and green and likes to bowl?
An alley-gator.
   
Google Books
Fabulous and Funny Clean Jokes for Kids
By Bob Phillips and Steve Russo
Eugene, OR: Harvest House Publishers
1996
Pg. 87:
Myrtle: What do you call a crocodile that enjoys bowling?
Winifred: I have no clue.
Myrtle: An alley-gator.
 
28 March 1997, The News Journal (Wilmington, DE), “Just For Laughs,” HoursPlus sec., pg. 21, col. 5:
Q: What do you call a crocodile that likes to go bowling?
A: An alley-gator.
Rob Palute, age 10
Newark
 
Google Books
December 2001, Boys’ Life, “Think & Grin,” pg. 62, col. 3::
Lyle: What do you call a crocodile that is an expert bowler?
Kyle: What?
Lyle: An alley gator. — Kyle Trawick, Conroe, Tex.
 
Twitter
miriam gundred
‏@mgundred
What do you call a crocodile that likes to bowl? An alley-gator!!! #PopsicleStickJokes
5:45 PM - 31 Mar 2010
 
Twitter
Roachpop
‏@calypto
What do you call a crocodile that likes to go bowling?—-An alley gator.
2:44 AM - 23 Sep 2010