10 Aug 2017

The last dance? Critically Endangered grebe’s mesmerising display filmed for first time

On the remote glacial lagoons of Patagonia, a rare grebe performs a bewitching dance that has been caught on film for the first time. But with invasive predators and proposed dams threatening its existence, how long do we have until the music stops?

By Alex Dale and Francisco González Táboas, ‎Aves Argentinas

Firstly, let us begin with the footage you all came to see: the mesmerising, headbanging, courtship display of the Hooded Grebe Podiceps gallardoi (Courtesy of Living Wild in South America):










What’s happening here? Well, Hooded Grebes, like most grebes (a family of freshwater diving birds), are incredibly picky when it comes to the matter of choosing a mate. Before putting a ring on it, would-be grebe couples like to put each other through their paces to see if they measure up, testing their stamina, rhythm and co-ordination via an elaborate gauntlet of dance moves.

Since the Hooded Grebe is found in the isolated, and largely inaccessible, lakes of remote Patagonia, it’s had plenty of time to rehearse its elaborate dance routine in private; the species was only discovered by humans 43 years ago, and we’re still unlocking the secrets of this charismatic species.

This footage, filmed for the documentary Tango in the Wind, is the first time the Hooded Grebe’s spectacular routine has been filmed in such detail. But even though we discovered the species less than half a century ago, human impacts are already driving this beleaguered species towards extinction. American Mink Neovison vison, a semiaquatic mammal native to North America, was introduced to Patagonia for commercial fur production in the 1930s – decades before we even knew the Hooded Grebe existed.

A few minks escaped, and now they prey on the unprepared grebes, driving their numbers ever downwards. And now a pair of poorly-planned dams threaten to turn off the music on this Critically Endangered waterbird for good.

The Hooded Grebe is in steep decline. By the mid-1980s, the population was estimated at a minimum of 3,000 to 5,000 adult individuals. Today they do not exceed 400 breeding pairs. This situation has prompted Aves Argentinas (BirdLife Partner) to develop a range of research, education and conservation activities geared towards conserving the species known affectionately in Argentina as the 'Macá Tobiano’, both in its breeding area and in its wintering sites across the Argentine coast.

Since 2009, the Macá Tobiano Project has been working uninterruptedly with the central objective of halting the accelerated declines of the species – which has been driven not only by predation, but also by over-grazing of the lakes’ surrounding vegetation by livestock.

But all these efforts will be in vain if the project to dam the Santa Cruz River is allowed to continue. The Argentine Government, allied with Chinese companies, is planning to build two mega dams on the Santa Cruz River, which would likely lead to the destruction of the last glacier river in Patagonia, taking with it the around half the river’s ecosystem, and many of the species that depend on it. The dams would block natural processes, which will have an impact on the flow of rivers and aquatic ecosystems in the area. The availability of food downstream would also be affected, resulting in the loss of some of the Hooded Grebe’s most important wintering sites.

The Santa Cruz River is born from the melting glaciers of Patagonia, and travels 385km to its mouth in the Atlantic. Its winding journey is the preferred habitat of many species that are adapted to the climatic conditions of these latitude – not least the Hooded Grebe, an endemic species and a symbol of Patagonia. A few years ago, the State created a National Park to save the Hooded Grebe from extinction, and today that same State could sign his death.

The delicate nature of the Santa Cruz’ habitats means that in spite of the 100 lagoons that make up the river across its route, 70% of the population of Hooded Grebe are restricted to a handful of lagoons – recent counts suggest that 518 birds are found in just six lagoons.

Hooded Grebe parents carry their young on their back  © Living Wild in South America

Since the beginning of the conservation project, many activities are underway in order to recover the populations before it is too late. As a result, their main threats are now being controlled; not just American Mink, but also the production of Rainbow Trout Oncorhynchus mykiss and other species as Kelp Gull Larus dominicanus, which preys on the grebe’s eggs and chicks.

At the time of writing, we are in the fourth year of working to manage Patagonia's American Mink populations, one of the greatest threats to the species. The focus was on the area associated with the Lake Buenos Aires (in Patagonia National Park) plateau where the invasive predator’s impact is most acutely felt.  Forty traps were active for 120 days across four watercourses. This capturing effort allowed the removal of 26 minks, bringing the total to date to 114.

Meanwhile, the work related to the impacts of salmonids, specifically rainbow trout, in the high plateau lagoons of western Santa Cruz, aims to evaluate the potential capacity to restore environments that have been modified by fish farming activities in the last few decades. Del Islote Lake was defined as the first site to be restored from the impact of the introduction of rainbow trout. This lake housed more than 1000 adult individuals of Hooded Grebe in the 1980s (which made up around 20% of the global population of that time) and is crucial to the species' recovery. The impact by predatory birds such as gulls is controlled by the program "Guardians of Colonies", as well as census and monitoring of the species throughout its cycle.

But all these specific activities have no value if we cannot preserve their habitat. For this reason it is fundamental that we continue to fight against the dams planned in the Santa Cruz River.

In recent months, several environmental organizations in Argentina have initiated a firm and constant struggle against the construction of the dams. In that timeframe, a short documentary called "Killing the River" was created, that was released in Buenos Aires before more than 600 people. Also for the first time in the history of the country there was a public hearing in the national congress for the construction of dams. At that two-day hearing, more than 60% of exhibitors - including all environmental organizations - demonstrated against the dams. Today the works are stopped by a measure ordered by the Supreme Court of Justice, dictated thanks to the work of the organizations. But still, the dance continues, both in Argentina's boardrooms, and (for now at least), on the lagoons.

Do you want to help the conservation of breeding sites such as the Santa Cruz River?

Please donate to our Quest for a safer nest appeal.