In January this
year we launched an international online appeal to save the Hooded Grebe 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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Hooded
Grebe
The Hooded
Grebe - Podiceps gallardoi - is a medium-sized grebe found in the
southern region of South America. It is found in isolated lakes in the most
remote parts of Patagonia and spends winters along the coast of the same region.
Description
Unmistakeable,
largely white with a dark grey back extending up the hindneck to its black head
with contrasting white forehead merging into a reddish peaked forecrown.
Extensive white on the flanks. They have a bright red eye. Legs are darkish
grey and the feet are dark slaty blue. Sexes are similar, males having a
slightly longer bill. Juveniles have a pale lower forehead and black crown cap
contrasting with white lower parts of head and nape.
Call
The call is a ‘kee-kee-kee’ and ‘ki-wee ki-wee’.
Food
On the lakes
located on the Patagonian uplands, the main source of food is a small
invertebrate, the snail Lymnaea
diaphana. Several other items, mainly
amphipods or arthropods, are taken. Little is known about feeding habits on the
wintering grounds and on the lagoons where the grebes stop during migration.
Breeding
Courtship is very
complex, more so than any other grebe. They form colonies of several up to a
hundred pairs on dense floating aggregations of Myriophyllum elatinoides, laying two eggs between
December and February but never attempting to raise more than one chick. Incubation
lasts 20-21 days. Chicks are fed very small items at first, and after two weeks
the diet of the young switches to snails.
Conservation Status - Critically Endangered
This species has
a very small and extremely rapidly declining population within a very small
range. It is likely that birds may move between breeding sites on an annual
basis but recent absences from former breeding sites are now believed to
represent genuine declines.
The principal
threats to the species appear to be climate change and the introduction of
salmon and trout to private lakes on the Strobel plateau as well as predation
by Kelp Gulls - Larus dominicanus
and American Mink - Neovison vison.
Birdwatching
Ask Aves Birding
Tours/Safaris/Adventures to create a tour for you to see these beautiful
Grebes.