Iturria:
BirdLife International
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.
