Beasts of burden hardly get any attention for the loads they carry, whether they are hauled over mountains or across desolate landscapes. But these animals, in particular, the donkeys on the Greek island of Santorini, have become a major concern among animal rights groups.

The groups are charging owners with everything from neglect to animal cruelty by ignoring the needs of their utilitarian quadrupeds. The donkeys are forced to carry overweight cruise passengers on tourist junkets on some of Santorini's rustic inland attractions.

One tourist donkey path is coming under scrutiny in particular, which also happens to be one of the most popular routes. It takes visitors from the harbor at sea level up some 1,300 feet along cliffs and rugged terrain to the island capital of Fira. The half-hour trek is attractive enough for tourist to eschew the other option: a two-minute cable car ride to the same destination.

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One advocate for an animal rights organization called Help The Santorini Donkeys blames owners for ignoring the well-being of their animals. The donkeys are forced to carry people heavier than 20 percent of a donkey's total weight. Donkeys are supposed to only carry up to 20 percent of their total body weight. He also claims to have seen other violations among donkey owners who don't operate in the tourism industry, noticing the animals on several occasions struggling under the weight of cement blocks and even a washing machine.

British-based advocate group The Donkey Sanctuary was reportedly shocked by what they saw when they paid a visit to Santorini. They witnessed the exhausted animals hauling obese tourists and loads of junk without access to food, water or even shade. Untreated, the animals are subject to a great deal of stress and even spinal injuries.

Whether the owners are paying any attention to these protests is a matter of speculation. Their four-legged force is one attraction that accommodates some two million tourists who visit the island annually, including roughly 850,000 via cruise ship.

A petition calling for an end to the abuse is being circulated and has already gathered more than 70,000 signatures, while The Donkey Sanctuary has asked to meet with Santorini mayor Nikolaos Zorzos to discuss the matter.

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