Study suggests dogs may use Earth’s magnetic field to find shortcuts, even in unfamiliar territory

A recently published study may have uncovered how dogs, famous for their sense of smell and direction, can find their way home over many miles.

Dogs may use the Earth's magnetic field as a compass to take shortcuts and find where they want to go and be, according to a research article published July 30 in eLife Sciences.

"We equipped 27 hunting dogs with GPS collars and action cams, let them freely roam in forested areas, and analyzed components of homing in over 600 trials," the abstract of the article said. "When returning to the owner [homewards], dogs either followed their outbound track [‘tracking’] or used a novel route [‘scouting’]."

The inbound scouting track started out mostly with a short run along the north-south geomagnetic axis, regardless of the actual direction home, the article said.

"Performing such a 'compass run' significantly increased homing [efficiency]," the article said. "We propose that this run is instrumental for bringing the mental map into register with the magnetic compass and to establish the heading of the animal."

Hynek Burda and Kateřina Benediktová, researchers with the Czech University of Life Sciences in Prague, were listed as lead contact researchers of the article.

Burda, Benediktova and other author researchers in the article are from the Czech Republic and the United States.

The article referred to well-known anecdotal accounts of dogs' "impressive navigation abilities," including World War I "messenger dogs," and early 20th Century studies that looked into dogs' navigational abilities.

"Decades later a more comprehensive study observed consistent homing success in a total of 26 dogs displaced without exposure to visual cues in various geographic directions," the article said. "Dogs often homed using novel routes and/or shortcuts, ruling out route reversal strategies, and making olfactory tracking and visual piloting unlikely."

The article's study used GPS and action cam video to analyze the dogs' orientation.

"We expected to find evidence for either tracking or scouting, to test the predictions about the route length and duration, and to see indications for the type of decision made at the turning point," the article said. "Furthermore, we expected that should visual piloting [orientation toward landmarks] take place there would be an effect of the height of the dog as [taller] dogs should have better overview [farther horizon] than [shorter] dogs."