With the arrival of the cold, the guanacos begin their seasonal migrations between the plateaus and the lower areas of the Patagonian steppe. This movement, which occurs every year between March and June, sustains the ecological balance of the region. Although it does not follow exact dates, snowfalls on the plateaus are the main trigger for these movements.
In the northwest of Santa Cruz, the groups remain on the plateaus during the summer, taking advantage of the tender grasses. When winter sets in, they move to lower areas, repeating routes that are passed down from generation to generation.
Migrations and Social Learning
According to biologist Emiliano Donadio, scientific director of Rewilding Argentina Foundation, migrations involve large groups of individuals and are repeated every year. However, not all guanacos migrate, even in similar environments. This opens a scientific debate: why do some groups move and others do not?
Recent studies suggest that migration might depend more on socially learned information than on a genetic program. Young animals learn routes and timing by observing experienced individuals, especially adult females and leaders. In this sense, migration is conceived as a cultural phenomenon, rather than instinctive.
Barriers and Threats
The problem arises when migrations are interrupted. The “cultural memory” that sustains these routes erodes and can disappear. Fences are one of the main barriers:
- In winter, snow prevents guanacos from jumping over them, leaving them trapped and dying from cold or starvation.
- Throughout the year, many animals die caught in them. A study by CONICET in Río Negro revealed that at least 6.4% of the population dies this way, which extrapolated to all of Patagonia implies thousands of individuals per year.
Possible Solutions
To reduce deaths, simple but effective measures have been tested:
- Remove the top wire of the fences, responsible for most of the entanglements.
- Modify the intermediate wires to allow the passage of young animals.
Preliminary data show a significant decrease in deaths where these interventions were applied. However, the scale of the problem requires implementing these solutions throughout the species’ distribution area.
Ecological Impact
The loss of migratory processes not only affects guanacos but also the functioning of the steppe:
- The redistribution of nutrients is interrupted.
- The dispersal of seeds is limited.
- The environmental heterogeneity that connects ecosystems in space and time is lost.
In other words, when movements are halted, the steppe also changes. Guanacos are key pieces in the ecological balance, and their migration ensures the continuity of vital processes for Patagonian biodiversity.
Each winter, guanacos repeat invisible but essential routes for the life of the steppe. Science seeks to better understand these movements, while conservation faces the challenge of removing barriers like fences. Protecting migrations means preserving not only the guanacos but also the ecological functionality of Patagonia.
