"September brings réttir—the nationwide roundup where people on foot, ATVs or Icelandic horses retrieve their stock from the mountains and valleys, aided by trusty sheepdogs. The grueling endeavor sometimes requires days in the saddle, and entire communities turn out in support." From: celebrating-rettir.
This is Réttir in Iceland, the transhumance process of moving sheep from their summer grazing grounds to their winter shelters. There are no Livestock Guardian Dogs needed, as the only lamb predator in Iceland would be the Arctic_fox, which generally eats smaller mammals, eggs, birds and plants. In spite of there being no LGDs in this country, I'm including this for educational purposes.
History of Dogs and sheep in Iceland
"The Icelandic Sheepdog is a breed of dog of spitz type originating from the dogs brought to Iceland by the Vikings. It is of similar type to the Norwegian Buhund, the Shetland Sheepdog, and the Welsh Corgi. They are commonly used to herd sheep in the Icelandic countryside....In the Icelandic landscape, sheep often get lost and it has historically been the dog's job to find them and return them to the herd. They are, therefore, used to working on their own and to figuring things out for themselves, so owners have to beware lest they learn things they should not. As a watch dog, their main task was to alert the inhabitants when somebody was coming."
From Wikipedia: Icelandic_Sheepdog