This animal behavioral study observed 36 domestic dogs to assess whether magnetic fields from high-voltage power lines influence dogs' geomagnetic alignment behavior. Dogs showed bimodal alignment under control conditions and under north-south oriented power lines, but alignment became trimodal under east-west oriented lines with statistically significant differences versus control. The authors interpret these findings as indicating that power-line-related fields can alter orientation behavior and frame this as supporting concern about biological effects of EMF exposure.