The shores of Lake Zablatsky, near Trebon in the Czech Republic, were a hive of activity on Monday.

The occasion: the annual carp haul, a centuries-old practice where fishermen descend to the lakes in the southern Bohemian region to harvest carp (above), before the Christmas festivities begin.

The freshwater fish is eaten during the traditional Christmas Eve dinner in the Czech Republic.

As part of an age-old custom, fishermen lined up to pull in their heavy nets from the water (left).

Many other customs have been preserved as well, Spanish news agency Agencia Efe noted in a report. In order to join the guild, fishermen must undergo several rituals, such as being hit on the bottom with a beater and having water poured on their trousers.

Once the carp are caught, they are kept alive until they can be sold in the days leading up to Christmas.

The carp are increasingly exported to other central European countries where they are very popular, the report added.