More than 80% of Scots think buying a puppy online is unsafe, according to a survey by the Scottish SPCA.
But the animal welfare charity, which questioned 3,188 people, found 35% of Scots do not feel confident they would be able to tell the difference between a responsible breeder and a puppy dealer.
The Scottish SPCA said the puppy trade in Scotland is reported to be worth around £13 million a year, and irresponsible breeders almost exclusively sell puppies online.
Its chief superintendent Mike Flynn said: “There tends to be a spike in interest in buying a pup during the school holidays.
“Combined with lockdown, many people being at home more and a lack of supply from responsible breeders, it is a perfect storm for puppy dealers and traders to profit.
“The fact that one in three Scots would struggle to tell whether someone is a responsible breeder is a sign of how hard a dodgy seller will work to create the impression they are genuine.”
The survey showed around 15% of people believe they have bought a puppy from an irresponsible breeder.
Of those, 45% said they were unable to get any paperwork or information about they puppy, while 25% said they were told they could not meet the mother of the dog they were buying.
Almost one-quarter (23%) said the puppy they bought became unwell or died shortly after they purchased it.
The survey also found one in five people believe they should be able to take their puppy home shortly after they have purchased it.
But responsible breeders typically have waiting lists and there can be several months between buying a puppy and actually taking it home.
Mr Flynn said the next-day delivery culture people have grown used to works to the advantage of puppy breeders.
He added: “The criminals involved disappear just as quickly as they sell a dog.
“When the problems start, the people who bred and sold the dog are nowhere to be seen and the buyer is left in horrendous emotional distress and with a considerable vet bill.
“I’ve said it so many times – we will continue to take the fight to the puppy trade, but the only way we can stop it once and for all is for the Scottish public, many of whom we know are animal lovers, to say no to puppy dealers and adopt or buy responsibly.”
Minister for rural affairs and the natural environment Mairi Gougeon said: “The increased demand for puppies that we have seen as a result of the coronavirus crisis shows the scale of the challenge we face tackling irresponsible and illegal breeders who are driven purely by profit.
“We are committed to ensuring the sale of puppies is undertaken responsibly and safely. Our legislation, which has been in place in Scotland since 2009, already requires dealers to be licensed.”