A first aspect provides a device for collecting a specimen in a fluid having a substantially directional flow relative to the device and substantially parallel to the device. The device comprises an elongated body and a plurality of substantially continuous barriers, radially extending relative to the longitudinal axis from a surface of the body and provided along the length of the body. With the barriers provided concentrically along the length of the body, like substantially perpendicularly to the length of the device body, the velocity of the flow of the liquid in which the specimen are to be collected is significantly reduced. Such reduction of flow velocity improves the odds of a specimen being retained by the device for collection. The barriers may form a directional receptacle.
