HOODED GREBE (MACÁ TOBIANO)
The Hooded grebe (Podiceps gallardoi) is depicted in Ambiente Sur’s logo. This is not accidental, since our researchers, through their field work, bird counts and annual species surveys, provided key information for updating knowledge about the populations of this seriously endangered bird. The macá is a symbol of our Patagonian region and of our commitment to it, and its mere existence depends exclusively on us.
This species was discovered as early in 1974 in the Los Escarchados Lagoon, province of Santa Cruz. It was declared Provincial Natural Monument by Law # 2582, passed in 2001. It is a noteworthy and quite large bird that weighs about a pound (500 g), boasts a colorful plumage and an unmistakable voice, and performs an elaborate and attractive mating dance.
In the two decades following its discovery, a thorough study on the Santa Cruz’s plateaus was carried out. The Hooded grebe population was estimated at that time somewhere between 3,000 and 5,000 individuals. In 1994, the discoveries of some of the bird’s wintering sites gave way to a calm period because it was assumed the species was safe due to its numbers and the apparent isolation of its habitat. Almost a decade passed before winter counts by researchers who later formed Ambiente Sur started to turn out alarming results that were acknowledged by Aves Argentinas. This NGO, a partner of BirdLife International, later also made an alliance with Ambiente Sur intended to save the Macá tobiano from its imminent extinction.
Systematic and intensive sampling was carried out throughout the breeding area of this species. The results obtained have generated enough information to raise the species to its current “Endangered” conservation status globally, according to BirdLife International-IUCN, and “Critically Endangered” in Argentina.
Data from recent studies suggests the Hooded grebe population has declined due to several factors that hit it directly. The introduction in the region of Salmonidae fish, mainly rainbow trout, is one of the main threats since they compete for the food, and also generate important changes in the quality of water bodies. On the other hand, the presence of the American mink (Neovison vison), a non-native species, within the Macá tobiano summer distribution range means a great danger for this species. The mink, a predator originated in North America, became feral in Patagonia and the strong impact it has on bird populations near streams and lakes was already registered. This species destroys whole bird colonies and nests when feeding.
The climate issue, however, is one of the most complex challenges to be faced. The Hooded grebe builds its nests in a kind of floating platform in lagoons and lakes using a plant locally called vinagrilla (Myriophyllum elatinoides). Strong wind storms, which have increased in the last few decades due to Patagonia’s warming, have destroyed many of the nesting attempts observed in the past.
It is also clear the increasing number of Southern black-backed gull (Larus dominicanus), a well-known macá tobiano predator that benefits both from the fishing industry and the poor waste management in human settlements.
What steps do we take to protect the Hooded grebe?
Monitor colonies during the summer. We aim to be able to learn each year’s reproductive success, and also to make population estimates in winter.
Monitor colonies during the winter.
Predator control. Mink traps and better waste control in the fields to reduce the gull populations.
Deploy efforts for regulations for the fishing industry, regarding salmon farming in lakes and lagoons in Santa Cruz
Capture some Macá tobiano specimens. In order to ring them and learn data about migrations, age, and fidelity to nesting sites, among other issues. This allows us to take efficient protection measures and to know more about the species’ lifecycle.
Community environmental education. We offer conferences, documentaries and field trips looking for society’s active involvement Your collaboration is vital to continue the work of the Macá Tobiano Project