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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
Tracking tiles: (A) with rodent footprints; (B) determining the percentage area marked by rodent footprints by placing a transparent plastic sheet marked into 16 cells on top of the tile.