translate English to French: Close cooperation and exchange of experience took place between those authorities.  One of the platforms for such exchange was the annual conference of the Customs Criminological Office on investigations in the field of species conservation, which was attended by officials of the customs investigation service, the police and the nature conservation authorities, as well as by experts from other European countries.
Ces services coopéraient étroitement et partageaient leur expérience, notamment dans le cadre de la conférence annuelle de l'Office de répression des infractions douanières consacrée aux enquêtes sur la préservation des espèces, à laquelle participaient des représentants des services des enquêtes douanières, de la police et des organismes de conservation de la nature, ainsi que des experts venus d'autres pays européens.