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Iturria: BirdLife International

Hooded Grebe Appeal – Action on breeding grounds already delivering results

Tue, Jun 26, 2012

In January this year we launched an international online appeal to save the Hooded Grebe Podiceps gallardoi as a new BirdLife Preventing Extinctions Programme initiative, building on earlier support provided by the Aage V. Jensen Charity Foundation as part of BirdLife’s High Andean wetlands initiative. We are delighted to report today that conservation actions undertaken earlier this year are already delivering results.
Hooded Grebe is endemic as a breeding species to Santa Cruz province in Southern Argentina and is now so threatened it has been uplisted to Critically Endangered in this year’s IUCN Red List update.
Previous research has identified that the main threats to Hooded Grebe are nest predation by an increasing population of Kelp Gulls Larus dominicanus; predation of adults by introduced American Mink Neovison vison; predation and competition for food resources from alien Rainbow Trout Oncorhynchus mykiss; loss of breeding sites through sedimentation as a result of land erosion caused by overgrazing; and breeding failure, due to increasingly strong winds, that are detaching floating nests from their moorings.

An adult Hooded Grebe on its  floating nest – © S Imberti

Urgent conservation action is now underway for the Hooded Grebe to address these threats led by BirdLife National Partner and Species Guardian – Aves Argentinas and local Patagonian NGO – Ambiente Sur, who are both working around the clock to prevent its extinction.  During the first few months of 2012 (the austral summer in Patagonia) the two organisations led a substantial field team to the grebe’s breeding grounds to attempt a number of pioneering conservation initiatives.
Please click here to visit our appeal page and see a video of breeding Hooded Grebes filmed by the conservation team earlier this year. 
We are also seeking BirdLife Species Champions for the Hooded Grebe. If you or your company would like to find out about this opportunity please email species.champions@birdlife.org

The immense, remote plateaus of Santa Cruz Province – © Andrea Pigazzi

The Hooded Grebe Conservation Team visited 180 lakes in the remote plateaus of western Santa Cruz province, an area that covers nearly 20,000 square km. A total of 13 people participated in the fieldwork including naturalists, ornithologists and biologists, from Aves Argentinas, Ambiente Sur, Buenos Aires University, the Austral Centre for Scientific Research, the Santa Cruz Birdwatchers Club, and the Argentinian National Parks Service. Important information was obtained about the reproductive biology of the Hooded Grebe and the factors that affect its reproduction, such as predation by Kelp Gull, American Mink, and increasing wind gusts.

Visiting lakes with officials from the National Parks Service - © Pablo Hernandez

The team’s first action was to assess the species’ abundance at known breeding colonies and investigate its presence at several new locations. Results from this survey confirmed the very precarious conservation status of the species, though several new colonies were discovered. A total of 265 breeding pairs were located of which just 64 were successful.

Colony Guardians collecting field information – © Hernan Casañas

This year a pioneering new approach dubbed “Colony Guardians” was trialled at El Cervecero Lagoon, one of the most important Hooded Grebe breeding locations on the Buenos Aires Plateau. Last year the significant colony there was wiped out when invasive American Mink slaughtered more than 30 breeding adult Hooded Grebes at this one site, leading to 40-plus eggs also being left abandoned. This year, a team of three scientists acting as Colony Guardians monitored the birds throughout the breeding season with one of the team always present during the important stages of incubation, hatching and the initial parental care of fledglings.

A predatory adult Kelp Gull – © James C Lowen

The Colony Guardians approach made a big difference, helping to protect the breeding birds from avian predators including their primary threat – Kelp Gulls - which have been increasing throughout the province since assessment began in the ’80s. This year a breeding colony of Kelp Gulls was located at a site in the middle of the Buenos Aires Plateau for the first time, rather than at their historical breeding areas along rivers and the marine coast of Santa Cruz province.

An adult Hooded Grebe protecting its chicks – © Pablo Hernandez

In addition to combating aerial predation, the team also set a number of traps for mink. While evidence of mink was again clearly present this year, none were caught in traps. Apparently the Colony Guardians’ human presence was sufficient to deter the mink from a repeat attack. As a result of the predator control actions, breeding success at the colony has greatly improved over the norm and some 60% of nests were successful, with most of the young reaching the juvenile stage. This is a higher reproductive success than has been historically recorded for the species anywhere else.
Following their anti-predator activities, the Colony Guardians at El Cervecero Lagoon were also able to catch and apply individually marked wing tags to several of the adult and juvenile Hooded Grebes present. This activity was also conducted at other colonies and a total of nine birds were tagged including three juveniles. The plan was to monitor these birds at the lakes but hopefully also then try to record them on their wintering grounds when they had migrated to the unfrozen fjords of the Santa Cruz south-eastern seaboard.

Colony Guardians at El Cervecero Lagoon Preparing for wing-tagging Hooded Grebes

The wing-tagging activity is not without risk to the conservation team. To catch the grebes, a small inflatable dinghy is used to approach the birds in deeper water where they make their floating nests.  The tagging operation is conducted in half-light and usually the naturally windy conditions at the lake make handling a small craft bobbing about on the waves quite a precarious platform. Falling in the icy water is clearly not to be recommended. This year dramas were luckily averted, and using a strong torch to distract and transfix the birds, they were simply caught in a long-handled fishing net and processed as quickly as possible to avoid any unnecessary stress.

One of the wing-tagged grebes shortly before release.

The wing-tagging activity proved an instant success, with researchers able to monitor the progress and behaviours of individual birds with considerable accuracy, contributing to a far greater understanding of their ecological requirements. One of the tagged juveniles, along with another juvenile and three adults, was found to still be present on the partially frozen El Cervecero Lagoon as recently as May 8th.
Remarkably, in the last few days, a wing-tagged juvenile Hooded Grebe has been seen at Rio Gallegos on the coast in the far south-eastern part of Santa Cruz province. Volunteers conducting biological research there made the sighting and, having heard about the project to save the species through the considerable national publicity that has recently been generated in a variety of media, passed on the news.  This young bird has been identified from its unique number as one of the individuals tagged by the Colony Guardians at El Cervecero Lagoon.  This is not only the first time the origin of a wintering Hooded Grebe has been confirmed, it is also the first time a juvenile has ever been recorded on the wintering grounds.

The juvenile wing-tagged Hooded Grebe still present at its breeding site in May 2012.

Throughout the summer the Hooded Grebe Conservation Team has also been working closely with landowners, local food producers and their staff, and local authorities, informing them of the uniqueness of the Hooded Grebe and its plight, and of the simple measures that can be undertaken to help secure its future. This has been a gradual process of building trust that will provide a strong foundation for future action, including support for the protected area, and on-the-ground action such as predator control and habitat restoration on private properties. A number of landowners are already actively collaborating with the team.
About two years ago, Ambiente Sur and Aves Argentinas developed and presented a proposal to the Argentinean Government’s National Parks Authority, for the creation of a protected area within the Buenos Aires Plateau. Several colonies of Hooded Grebes breed inside the boundaries of the proposed protected area.  Since then, both organisations have been providing additional technical information and lobbying for the creation of a new national park. Recent feedback from the National Parks Authority suggests that approval of a law creating a protected area for the species may now only be a few months away. If successful, the creation of a new national park will afford Hooded Grebe the highest level of legal protection available for its habitat.

A dead Rainbow Trout – the main threat to Hooded Grebe on the Strobel Plateau.

The main area where introduced Rainbow Trout are a problem is south of the Buenos Aires Plateau in the Strobel Plateau.  The effect of the introduced trout there has been so great it has reduced Hooded Grebe breeding by more than 98% in the last 25 years.  In addition to reducing food sources, the presence of trout leads to a change in the turbidity of the water, which prevents the growth of “vinagrilla”, the filamentous plant that provides indispensable nesting material for all the water birds that breed in the lagoons. During the summer, substantial information was gathered by the Hooded Grebe Conservation Team about the impact of introduced trout in the lagoons there, which will be published shortly. This information will be used to inform provincial technicians and officials about the need to legislate appropriately to restrict further introductions.
As part of their outreach work in the area this year, the Hooded Grebe conservation team has also been holding meetings with local authorities (mayors, and other local government representatives) to explain about the threat that the introduced trout pose to the Hooded Grebe. These meetings have received a good reaction with offers of future support made by several stakeholders.
With support from the National Secretariat of Tourism, the Hooded Grebe conservation team has also begun the development of a bilingual video on the species, to promote its conservation at a national and international level. The video will be available in July 2012.

Filming Hooded Grebe conservation for the new documentary - © Pablo Hernandez

Next actions planned for the project are to repeat the work conducted this year but focus on some specific additional activities. Firstly the conservation team would like to increase the numbers of breeding sites at which Colony Guardians operate. If funding were secured, the plan would be to repeat the successful pilot at El Cervecero Lagoon at three additional colonies in 2013.
Restoration of the lakes in the Strobel Plateau is also a priority. Several measures to reduce numbers of introduced Rainbow Trout and combat land erosion (which leads to silting) at various private lakes there will be attempted.
A third measure that builds on the initial wing-tagging exercise is to establish a satellite-tracking scheme. In this way it is hoped birds tagged with transmitters can be constantly monitored by conservationists throughout their migration, providing important information about the routes they take, clarifying the risks they encounter and establishing where they spend the winter.
The cost of this urgently required action will be a minimum of $20,000 for the tagging alone, so unless more funding can be secured, very few of the planned measures will be possible in future years.
There is clearly much to be done if the fortunes of the remarkable Hooded Grebe are to be turned around. A robust plan is in place and work has already begun thanks to support from the Aage V. Jensen Charity Foundation and funds raised locally and through the international appeal. However, significant new funding is now urgently required to deliver this ambitious project and achieve long-term success.
Every little helps and every one can join in. If you would like to help save the magnificent Hooded Grebe from slipping away, within just four decades of its original discovery, please click here to make a donation online today.
If you or your company would like to become a BirdLife Species Champion for Hooded Grebe, please contact species.champions@birdlife.org
Facebook friends can follow the latest news on the Aves Argentinas and Ambiente Sur team’s work (in Spanish) by visiting their Facebook pages here.
On behalf of all the conservationists, scientists and volunteers working tirelessly on this project we would like to thank all those donors and new Species Champions who have responded so generously so far.
This appeal news is brought to you by The BirdLife Preventing Extinctions Programme.