A canid on the move
The maned wolf, Chrysocyon brachyurus, is South America's largest canid, yet it is not a true wolf. Standing up to 110 cm (43 in) at the shoulder, its most noticeable features are its disproportionately long, black legs, which have earned it the nickname "fox on stilts". This solitary omnivore is native to the open grasslands and savanna of the Cerrado region in Brazil, Paraguay, and Bolivia. However, its established geographic range is changing. In recent years, scientists have documented the species expanding its territory southward into northern Argentina, including the grasslands and wetlands of Corrientes Province.
This expansion is not a sign of a thriving population; the species is listed as Near Threatened by the IUCN, but an adaptation to widespread habitat alteration. The primary driver is the conversion of forests into open agricultural land and pastures, which inadvertently creates new, suitable habitat for this grassland specialist. A 2022 study revealed that the maned wolf's area of occupancy in Argentina is now 61% larger than it was between 1988 and 2008. This rapid ecological shift is tracked by networks of motion-activated camera traps, providing researchers with invaluable data on the animal's new distribution and behavior without direct interference.
Life in a changing landscape
The maned wolf's diet is unusually varied for a canid, consisting of about 50% animal matter and 50% plant material. They hunt small animals like rodents and birds by tapping the ground with a front foot to flush them out. A significant portion of their diet, however, is a tomato-like fruit called the wolf's apple, or Solanum lycocarpum. This fruit is believed to help protect the wolf from the giant kidney worm, a potentially fatal parasite. As a prolific fruit-eater, the maned wolf is an important seed disperser, shaping the plant communities of the ecosystems it inhabits.
In Argentina, organizations like Rewilding Argentina monitor the maned wolf population in Iberá Park using camera traps and VHF radio collars. This technology allows for detailed studies of their territory use, reproduction, and feeding habits in these new environments. While the creation of new grassland habitat seems beneficial, the expansion also brings the wolves into closer contact with humans. Analysis of over 1,000 recent maned wolf records in Argentina showed that nearly half involved hazards like road collisions, attacks by domestic dogs, and roaming in urban areas. This highlights a complex conservation challenge: an animal adapting to human-caused landscape changes simultaneously faces increased threats from human activity.