DNA extraction
We extracted the faecal pellets by using the NucleoSpin® Soil extraction kit (Macherey-Nagel, Düren, Germany) following the manufacturer’s guidelines. For the Tequila bat samples, we homogenized the sample (2 x 150 sec at 50 Hz) by using a SpeedMill PLUS (Analytik Jena, Jena, Germany). To maximize DNA yield, we conducted consecutive elutions (2 x 50 µl) with a preheated (ca. 45°C) SE buffer. For the mockingbird samples, the samples were washed in 50 µl SE Buffer and then homogenized using the same procedure as with the Tequila bat samples. We stored the extracted DNA at -20°C.