The “La Esperanza” Wildlife Refuge is located in the northeast of the Chubut Province, 75 km north of the city of Puerto Madryn.
It has a surface of 6700 ha. that includes 12 km. of the southern coast of the San Matías Gulf. The area is intended for biodiversity conservation and is strategically located in the buffer zone of the “Península Valdés” Protected Natural Area, declared UNESCO Natural World Heritage.
In 2003 it was declared a Wildlife Refuge according to Provincial Law No. 3257 and decree No. 868/90 by the Flora and Fauna Office of the Chubut Province.
In a world in constant change and with an actively growing human population, concern about environmental deterioration has become an increasingly common cause. However, Argentina’s formal system of Protected Natural Areas currently covers less than 5% of the country’s total area. That’s why buffer zones constitute a great opportunity to improve this number.
Fundación Patagonia Natural manages these lands, with the objective of preserving a representative area of the patagonian coastal steppe. Research programs on the ecosystem and its biodiversity, conservation programs for the environment and its species, and training activities are carried out there, supported by the “Introduction to Conservation Program.”
Steppe, culture and ocean
The climate of the area is characterized as arid, although tempered by its proximity to the sea and by being in the lee of the last step of the Patagonian plateau. It has an average annual temperature of 13.5ºC. The average monthly temperature varies between 6.4ºC in July and 20.4ºC in January, but sometimes exceeds 30ºC. Precipitation ranges between 100 and 200 mm. annual. Winds from the west and southwest predominate.
Vegetation
The Refuge has a high variety of plant communities, dominated mainly by a shrub steppe, where jarillas and algarrobos trees are common, and a shrub-herbaceous steppe, with different species of coirones and shrubs, many of them endemic to the region.
The plants of the Patagonian steppe, like all plants of arid zones, have developed adaptations in the leaves, stems and roots that allow them to survive in conditions of low humidity, high evapotranspiration, strong winds and extreme temperatures.
Fauna
In “La Esperanza” a total of 81 different species of animals, 5 species of shorebirds and 17 species of seabirds have been surveyed. A large number of species of land birds have been sighted nesting or engaging in reproductive behavior.
Twenty three species of native land mammals and at least two species of exotic mammals have been observed. Studies carried out in the Refuge allow us to see a growth in the population of Guanacos (Lama guanicoe) from 2000 to the present, where around 700 individuals are observed. In the Refuge, the presence of Pumas (Puma concolor) was practically continuous between the year 2000 and until August 2004. From that date until June 2008, no signs of presence, such as feces or footprints, were recorded.
From June 2008, traces of puma activity were found again within “La Esperanza”. Six species of marine mammals have also been sighted. On the coast there is a roost for Sea Lions (Otaria flavescens) with juvenile and non-reproductive animals with few offspring. On the shores of the refuge, there are rocky reefs on which a very large diversity of organisms such as fish, octopuses and other invertebrates live.
Geology and Fossils
The refuge is included within a large landscape of gentle slopes, terraces and depressions. The coast features a 12 km long pebble beach.
The structure of the beach is a steep slope composed of gravel-type sediments accumulated by the action of the sea. From the beach you can see the marine terraces formation.
Most of the fossils found in La Esperanza belong to the so-called “Puerto Madryn Formation”, with yellowish to ocher colored sediments, with a significant content of sand and frequent banks of oysters (Ostrea parasitica and Ostrea maxima) and others. invertebrates mostly well preserved.
History and Culture
The Refuge is located in the distribution area of the northern Tehuelches, original inhabitants of this portion of the territory. In the area there are sites of archaeological interest associated with coastal slopes, mostly located on marine terraces with easy access to the sea.
The studies carried out indicate that the area would have been repeatedly used for at least the last two thousand two hundred years by these inhabitants.
Most of the archaeological record would have been formed by successive occupations related to the collection of mollusks, occasionally fishing and hunting of guanacos and choiques. Some very brief occupations are presumed, others a little longer, temporary camps and only one site that seems to have functioned as a residential base. In some occupations of late times, ceramic containers with globular shapes and smooth walls would have been manufactured using local clays as raw materials.
Starting in the 20th century, extensive sheep farming began to develop in the place, as in the rest of Patagonia, until the area was defined as a Wildlife Refuge, at which time it was decided to remove the livestock, close the area and put it under the recovery regime.