It seems it's illegal for a husband to catch a fish unless accompanied by his wife.
5 seconds sound clip from the Mister Ed - Season 1, Ep. 4 - Kiddy park TV Series.
You can hear this line at 00:06:02 in the DVD version of the movie.
Quote context
[...]
- Oh, here's my darling breadwinner.
- Addison, would you mind driving me to...
- Kay, guess what? The boys want us to go along with them to Ensenada.
- No!
- Why, Addison, doll, whatever made you change your mind?
- It seems it's illegal for a husband to catch a fish unless accompanied by his wife.
- Ensenada. What a lovely idea.
- Honey, we'd better start shopping right away. We've got no time to lose.
- Right. I've got a million things to do.
- Wilbur, you'd better find a place for Mister Ed to stay while we're gone.
[...]