(CBS SF) – Sometimes we see dogs tethered outside of a coffee shop, a grocery store or the like – ostensibly, they’re waiting for their owners to finish their errands and retrieve them. Is this safe?

“Tethering a dog outside can cause many problems,” summed up Dr. Jack Aldridge, Director of Veterinary Services at the San Francisco SPCA. “An unmonitored, tethered dog is easy prey for a dog thief. When a dog is tethered he may feel trapped when approached by a perceived threat like another dog or a child. If the dog is not comfortable he may react in a confrontational manner, which is not safe for anyone.”

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How can you tell if a dog is uncomfortable?

“One of the most common behaviors to watch for is avoidance. If the dog is avoiding your interaction then he or she may not want you to approach and you should listen to that message,” Aldridge explained.

What should people do if their dog wants to interact with a tethered dog?

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“If you’re walking your own dog you should cross the street to avoid having the two dogs greet one another on a leash. Greeting on a leash can create a lot of tension between the two unknown dogs and the tethered dog may be stressed by the confinement, in addition to the fact that his owner’s not present.”

So, what should folks do if they do intend to tether their dog?

“First of all,” said Aldridge, “this practice is illegal in many communities, including San Francisco. So I encourage owners to observe their dog’s behavior when tied on a leash and never, ever leave a dog out of your sight in a public place.”

KCBS’ Jeff Bell Reports:

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