Feral donkey (Equus asinus) eradications in the Galápagos

Abstract

Introduced herbivores are major drivers of ecosystem change and biodiversity loss, particularly on islands. Tools and techniques now exist to routinely remove introduced herbivores from islands, providing a powerful conservation tool. Here, we summarize the few documented feral donkey removals on islands worldwide, and report on the removal of populations from the Gala´pagos archipelago, Ecuador. After decades of sporadic control programs on Santiago Island and Alcedo Volcano, Isabela Island, donkey populations were removed from both areas, concurrent with a goat eradication program. Both ground and aerial hunting programs were utilized. The latter method was highly efficient; donkeys were removed from Santiago Island with less than 80 h of aerial hunting. Given the clear impacts of introduced herbivores on islands worldwide, feral donkey populations should be routinely removed from islands.

<b>Dendrophysiological plant strategies of <i>Poincianella pyramidalis</i> (Tul.) L.P. Queiroz after wood herbivory in semiarid region of Paraíba - Brazil

“…This species is used as transportation and workforce because of its resistance and adaptation to climate of the Semiarid: hot and dry areas (> 25°C annual mean and < 800 mm annual total). Abandoned individuals of E. africanus asinus refuges in wild areas and, when hungry and thirsty, they eat plant tissue (leaves and branches) to get food and water of native plant species (Freeland & Choquenot, 1990;Carrion, Donlan, Campbell, Lavoie, & Cruz, 2007). Constant damage to plants caused by animals (herbivory) results in biological responses from plants.…”

Field Immobilization of Feral ‘Judas’ Donkeys (Equus Asinus) by Remote Injection of Medetomidine and Ketamine and Antagonism With Atipamezole

“…In northern and western Australia, large feral donkey populations now impact conservation and agriculture and pose a threat as potential exotic disease hosts (Bradshaw et al, 2007). Overgrazing by donkeys results in direct competition with domestic stock and exacerbates land degradation and habitat destruction (Choquenot, 1990;Carrion et al, 2007). As an integral part of feral donkey control programs, the Judas technique has been used to aid aerial culling since 1994.…”

Understanding Invasive Species in the Galapagos Islands

“…Rats, dogs, and cats in some of the smaller islands (Baltra Island) represented the best case for the eradication of cats, followed by a land iguana reintroduction (Carrion et al 2007). Cats were eliminated using xxi Tomahawk and Victor traps, poison baits, and rifle shots.…”

“…The scientist James Gibbs posted that he encountered some 100-300 saddleback tortoises in the island, which evidences an important recovery (Nicholls 2015). Pigs (Cruz et al 2005) and donkeys (Carrion et al 2007) are large mammals that have also been successfully eradicated in the Galapagos.…”

“…Given its magnitude and impact, the most important example of a large-scale eradication is that of the elimination of the goats from Santiago, Isabela, and other islands (Carrion et al 2007;Márquez et al 2010). By placing tracking devices in the so-called Judas goat, often sterilized female goats on induced heat, hunters could track and eliminate large quantities of goats and pigs.…”