Hooded Grebes Were Thought to Journey

Hooded Grebes Were Thought to Journey

June 2010 1 Sep2011cover&contents.p65 1 9/2/2011, 5:35 PM FEATURE Patagonia has long attracted the quickly through Fundación on the high plateaus east of the Collecting field data on the attention of naturalists from all Vida Silvestre Argentina Andes. It breeds on a few species is harsh to say the least, parts of the globe. Yet this (FVSA, the Wildlife Foundation basaltic lakes in the interior of given the inhospitable habitat it remote region, which includes of Argentina) by creating a Santa Cruz, extreme south-west lives in, the ferocity of the the planet’s southernmost private reserve at Los Argentina, with only occasional weather, the poor accessibility wetlands and grasslands, still Escarchados lagoon, where the and poorly documented and the huge distances to be holds many of the natural grebe was discovered, about 150 records from near Torres del covered. The plateau lakes are world’s mysteries. km east of the well known Paine, in Magallanes, southern checked by researchers in 4WD In 1974, Mauricio Rumboll, Perito Moreno Glacier (Los Chile. vehicles, on horseback, or even a remarkable Argentinean Glaciares National Park). In winter, the species on foot. The researchers go naturalist, took part in one of At first, only some 250 undertakes an extraordinary equipped with clothing and the great discoveries that Hooded Grebes were thought to journey. When the high plateau camping gear designed for high Patagonia yields from time to exist; the species was considered lakes are frozen, the majority of mountain expeditions. time. He was immensely the rarest bird in the country. In the population moves to the After the winter discoveries surprised when one of his the subsequent two decades, a Atlantic coast of Santa Cruz of 1994, a period of silence and students brought to his attention thorough survey of the plateaus province, crossing the calm followed. The assumption a grebe that he soon realised of Santa Cruz province was Patagonian steppe. The only was that the grebe was safe, was new to science. It was an undertaken and the estimated known wintering grounds are given its numbers and the outstanding discovery, all the grebe population was believed the río Santa Cruz, Coyle and remoteness of its habitat. more surprising when we to be 3,000–5,000. This was Gallegos estuaries. The grebes Almost a decade went by. Then, consider that the Hooded Grebe probably a considerable migrate at night, making their news of the very low numbers Podiceps gallardoi is a rather underestimate, given the movements hard to track, so found in winter counts by the conspicuous and large bird, technological limitations of the mystery of where they went Asociación Ambiente Sur (AS), about half a kilogram in weight, fieldwork in those days. In 1994, in winter was not solved until based in Santa Cruz, was picked with colourful plumage, a it was downlisted from 1994. But the whereabouts of up by BirdLife Partner Aves distinctive voice and an Threatened to Near Threatened the immature birds during this Argentinas (AA). attractive breeding display. on the IUCN Red List. harsh season and their In 2009, a team of The emerging conservation During the breeding migration routes, remain a big naturalists and technicians from groups in Argentina reacted season, the grebe occurs solely unknown. AS and AA surveyed the most 16 WorldBirdwatch Sep20011Grebe.p65 16 9/2/2011, 4:16 PM Hooded Grebe was only discovered in 1974 (Diego Punta Fernandez) relevant plateau lakes over three very low, the species may be population, perhaps close to most isolated places. This weeks, counting grebes and adapted to survive a succession 80%, when compared to that industry is threatening not only attempting to locate breeding of poor breeding seasons. But, recorded in the 1980s. In the the future of the grebe but also colonies. The outcome was with numbers falling so rapidly, 1980s an average of 2,500 the rest of the wildlife present in disheartening: many of the lakes the loss of entire breeding individuals were found at the 78 those environments”, Gustavo were dry or becoming clogged colonies to wind damage could most important lakes, but in Costa added. Also evident are with silt as a result of the general have a significant impact. 2010/11 only 400 were detected, the increasing numbers of Kelp desertification of the region, Counts on the wintering despite surveying most of those Gull Larus dominicanus, a leading to changes in the grounds suggested a decline of 78 lakes and around 120 other known predator of the grebe that composition of the water. Water 40% over seven years. Surveys lakes. has benefited both from the fish levels at known breeding sites conducted in December 2006 While there is speculation industry and from poor waste were 2–3 m lower than in and January 2009, which that numbers fluctuate management at human previous years. revisited key known breeding dramatically at breeding sites settlements. Climate change might be a sites surveyed in 1987 and 1998, from year to year, driven by As if these problems were major threat to this species and also found sharp declines. movements rather than actual not enough to push an already its habitat: anecdotal reports Numbers fell from 452 to 51 at population fluctuations, the struggling species over the edge, suggest that recent winter Laguna del Sello. Laguna del overall declines detected on the a breeding colony which AA and snowfall has been much reduced, Islote, Tolderia Grande and wintering and breeding grounds AS were studying in March 2011 without a corresponding Lagunas Encadenadas, (700, 90 appeared to be real and rapid. was devastated by another pest increase in precipitation at other and 198 individuals repectively “Our teams started to be that is advancing in western times. Strong winds have caused in previous counts), no Hooded worried when we realised that Patagonia: the American Mink around 50% of all breeding Grebes were found. The species there was more than one cause Neovison vison. Over 30 breeding attempts in the last three years was uplisted from Near to tackle if we were to conserve adults were killed, and over 40 (2009–2011) to fail. Recent Threatened to Endangered in the grebe”, said Gustavo Costa, eggs abandoned. investigations indicate that wind 2009. President of Aves Argentinas. “This was a sad day, but at gusts have significantly increased The situation has worsened In many of the lakes in the least it meant that we had in recent decades. At other times since then: data obtained in the grebe’s core distribution, exotic discovered one other reason for this threat would be marginal; last three seasons point to a trout were being introduced. its decline—and a very with adult mortality naturally clear reduction in the estimated “Trout rearing has reached the frightening one at that—that September 2011 17 Sep20011Grebe.p65 17 9/2/2011, 4:16 PM Hooded Grebe: the next member of the ‘extinct grebes club’? reserve in 1979, but is now incredible ‘new’ species known to hold only a marginal fluttering to the same fate as the population. Six individuals were Alaotra Grebe, the Colombian recorded within Perito Moreno Grebe and the Atitlan Grebe. National Park, Argentina in Several key organisations are 1992. Key breeding lakes in the investing in this. They need our core of the grebe’s range lack any help.” kind of legal protection, but the Aves Argentinas is seeking population stronghold on funding for a range of actions to Meseta de Strobel is afforded ensure the survival of the some protection by its Hooded Grebe, including remoteness and inaccessibility. implementation of summer and “Thanks to support from the winter surveys in 2012, 2013 and ABOVE Surveying Hooded Grebes requires working in very remote areas AV Jensen Foundation, we are 2014, embracing the entirety of (Diego Punta Fernandez) prioritising Lago Buenos Aires the Buenos Aires, Asador, Las BELOW Introduced American Mink killed over 30 breeding adults in March plateau”, says Fabián Rabuffetti, Vizcachas, Viedma, Cardiel and (Ignacio Roesler) Director of Conservation at Aves Strobel plateaus, the Coyle and Argentinas. “This site should be Gallegos estuaries, as well as declared a Ramsar site (a any of the plateaus reachable in wetland of international winter. Surveys will also be importance) and there are carried out on previously opportunities to create a national unsearched plateaus. park in this area.” Among the On the ground, conservation targets of the action plan is agents will be assigned to the advocacy at a national level for species’ breeding and wintering the creation of a Hooded Grebe grounds during 2012, 2013 and National Park. 2014, to execute a monitoring The wild territories inhabited plan and implement by Hooded Grebe also harbour a conservation measures. vast number of animal and plant There will be a programme rarities, including endemic and/ to eradicate mink, to control or undescribed lizards. They are Kelp Gull numbers on the important for populations of breeding grounds and to protect restricted-range birds which breeding sites from strong occur only in the Southern winds. Local farm workers will could allow us to implement fewer than 250 individuals, had Patagonia Endemic Bird Area. be encouraged to become suitable management actions in suffered a further population Significant percentages of the ‘Guardians of the Hooded the field”, said Gustavo Costa. decline. world population of migrant Grebe’, monitoring the presence Members of the research “This is why we are Nearctic shorebirds such as or absence of the birds, and team in 2010 also observed developing an action plan for Baird’s Sandpiper Calidris bairdii giving early warnings of Hooded Grebes nests being the Hooded Grebe, that involves and Wilson’s Phalarope potential new threats to the robbed by Black-necked Swan research, pest control and Steganopus tricolor use these species.

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