: It must be caught between mid-May and early July.
: It is also known as maatjesharing , a corruption of the Dutch word for virgin ( maagd ), because the fish are caught before they have started their reproductive phase. The Culinary Tradition [Hollandse Nieuwe] Dutch Girls Have A Wet Pussy...
The phrase likely refers to , a celebrated Dutch culinary tradition centered on the first herring catch of the season. The specific wording in your request appears to be a provocative or humorous double entendre referencing the "wet" and "virgin" nature of the fish as it is prepared and consumed. What is Hollandse Nieuwe? : It must be caught between mid-May and early July