Shirasu is whitebait in Japanese. Whitebait are juvenile fish and mostly are anchovy in Japan. These whitebait are boiled and dried and eaten nationwide in Japan.
Enoshima, tied island offshore of Sagami bay, not far from Kamakura has a local specialty called Shirasu-don. It is a boiled whitebait on rice. Some of the restaurants offer nama-shirasu-don, raw whitebait on rice. To maintain the freshness of the whitebait is much difficult than other fish therefore must be eaten at the harbor which whitebait are landed.
However, you cannot order raw whitebait bowl between January and March due to whitebait are prohibited to be caught during this season. Therefore if you want to try the raw whitebait, please visit Enoshima between April and December.