Argentina farmers have nearly whipped out the Ruddy-headed Goose as a “pest,” but Falkland Islands sheep farmers benefit by sharing pastures with the geese.
By Rex Graham
Tierra del Fuego Island’s tall grasses are ideal breeding habitat, just as the lowlands of southern Argentina offer the geese a warmer retreat in winter. However, Ruddy-headed Geese there have been relentlessly hunted along with Ashy-headed and Upland Geese, sometimes with the use of aircraft. The Argentinian government also promoted massive destruction of Ruddy-headed Goose eggs on Tierra del Fuego.
Ruddy-headed Goose bluegrass blues
The now-rarely seen geese preferentially eat a bluegrass called Poa annua as well as Kentucky Bluegrass, Poa pratensis. Both types of pasture grasses also are eaten by livestock.
After Falkland farmers said the geese also competed with their sheep for grass, researchers at a Falklands grassland organization investigated. They discovered that the digestive efficiency of Ruddy-headed Geese is about 25%. They reported surprising findings in the Journal of Applied Ecology that goose droppings are a rich nutritional resource for sheep.
“The feed value of goose faeces to sheep, which often eat them, was measured in terms of digestibility and nitrogen content,” the researchers said. “They had a similar digestibility and nitrogen content to good quality grass.”
That study revolutionized the views of Falkland farmers: they allowed the geese to feed alongside sheep in their pastures.
However, the farmers of the South American mainland would hear none of it. They chose maltreatment over coexistence. “While the continental geese numbers were still dwindling from intense persecution, a new problem arose in their breeding grounds,” said a news release by BirdLife International. “Chilean government started introducing Patagonian Grey Foxes in Tierra del Fuego in an attempt to control the previously introduced European rabbit populations. The continental populations face now an uncertain future as the species struggles to make a comeback because their reproductive activity has diminished significantly.”
As many as 80,000 Ruddy-headed Geese flourish on the Malvinas and Falkland Islands.
Once “very common in Austral Magellanic steppe grasslands before 1950,” the mainland population of the species has declined 90% since the early-1900s. “The maximum size recorded for the genetically distinct continental population during the last 15 years has been 779 adults,” said a study published in 2016 in the journal Bird Conservation International.
Some protected areas have been established in Santa Cruz Province in Argentina, but there are no such protected areas on the Argentinian or Chilean portions of Tierra Del Fuego Island. There also are no protected areas on the species’ wintering grounds, according to the Bird Conservation International study. “Illegal recreational hunting still occurs in Buenos Aires Province,” the study said.