True to my word, I went out today and made the following observations of Southern Hemisphere dogs at the cost of a pair of ripped trousers and a rather painful tetanus booster.
It would appear that wind direction is more of a factor than magnetic North/South or the Earth's rotation. Unlike Canada, where one of our contributors noted his dog kept his back to the wind, dogs in the Wellington Region invariably face into the wind and with their mouths slightly open. As Wellington is notoriously windy, there may be some aerodynamic forces at play here but I am not qualified to comment.
Just as interesting was the choice of location. Rough grassy areas, where the results are difficult to see, were eschewed in favour of freshly mown lawns or carefully tended flower beds. This may have something to do with pride of display.
Next came driveways and pavements with, for those dogs that have a propensity for chasing moving vehicles, cycle paths. These allow the dog to indulge both its passions without the need for a change of location.
Further down the list, but each with its aficionados, came children's play areas and public beaches.
Conclusion:
It isn't clear from the OP if the original observation was the result of an academic study but, if it was, I would recommend the researcher be given a quick kick in the slats for wasting public money. And that is a FACT.
Pete