scholarly journals Molecular phylogeny of the South American sheldgeese with implications for conservation of Falkland Islands (Malvinas) and continental populations of the Ruddy-headed Goose Chloephaga rubidiceps and Upland Goose C. picta

2013 ◽  
Vol 24 (1) ◽  
pp. 59-71 ◽  
Author(s):  
MARIANA BULGARELLA ◽  
CECILIA KOPUCHIAN ◽  
ADRIÁN S. DI GIACOMO ◽  
RICARDO MATUS ◽  
OLIVIA BLANK ◽  
...  
Keyword(s):  
Sequence Data ◽  
Breeding Population ◽  
Tierra Del Fuego ◽  
Critically Endangered ◽  
Crop Damage ◽  
Falkland Islands ◽  
Continental Population ◽  
Population Size Estimates ◽  
Breeding Grounds ◽  
Upland Goose

SummarySheldgeese of the genus Chloephaga are waterfowl (Anatidae) endemic to mainland South America and the Falkland Islands (Malvinas). Continental populations of three species C. picta, C. poliocephala, and C. rubidiceps breed in Patagonia and Tierra del Fuego and migrate northwards to winter in central Argentina and Chile. These continental populations have declined by > 50% in the past 30 years due to direct hunting to control crop damage and by the introduction of the grey fox Dusicyon griseus to their breeding grounds in Tierra del Fuego. The continental population of C. rubidiceps is critically endangered, estimated to be < 1,000 individuals. While no historic population size estimates exist for C. rubidiceps in its wintering grounds, the breeding population in Tierra del Fuego was estimated to number several thousand individuals in the 1950s. In contrast, the C. rubidiceps population in the Falkland Islands (Malvinas) is non-migratory and stable with > 42,000 individuals, as is the Falkland Islands (Malvinas) population of C. picta leucoptera with > 138,000 individuals. Here we use sequence data from the mitochondrial DNA control region to quantify genetic divergence between insular and continental populations of these two species of sheldgeese. Chloephaga rubidiceps and C. picta showed significant intraspecific differentiation of 1.0% and 0.6%, respectively. In both cases, mainland and insular populations were reciprocally monophyletic and did not share mtDNA haplotypes. These results suggest that the insular and continental populations of C. rubidiceps and C. picta are genetically distinct and that female-mediated gene flow is restricted. We recommend a reevaluation of the threat category status of the continental C. rubidiceps population, under IUCN guidelines. It is necessary to implement urgent actions for the conservation of this critically endangered population.

Ruddy-headed Goose Chloephaga rubidiceps: former plague and present protected species on the edge of extinction

2016 ◽  
Vol 27 (2) ◽  
pp. 269-281 ◽  
Author(s):  
NATALIA A. COSSA ◽  
LAURA FASOLA ◽  
IGNACIO ROESLER ◽  
JUAN CARLOS REBOREDA
Keyword(s):  
Common Species ◽  
Tierra Del Fuego ◽  
Critically Endangered ◽  
Santa Cruz ◽  
Predator Species ◽  
Critically Endangered Species ◽  
Continental Population ◽  
New Information ◽  
Breeding Grounds ◽  
Conservation Actions

SummaryThe Ruddy-headed Goose Chloephaga rubidiceps has two separate and genetically distinct populations, one sedentary that inhabits the Malvinas/Falklands Islands and another migratory, which inhabits continental southern South America. New information suggests that these populations should be considered as different evolutionarily significant units. The latter population breeds in Austral Patagonia (Argentina and Chile) and overwinters in Central Argentina. It was a very common species in Austral Magellanic steppe grasslands before 1931, when it was declared an “agricultural pest” by the Argentinian government, together with other sheldgeese species. Since then, the continental Ruddy-headed Goose population has declined becoming one of the scarcest species in Austral Magellanic steppe. Nowadays, its population is categorised as critically endangered in Argentina and endangered in Chile. We present data from six road censuses conducted in the breeding areas of Santa Cruz and Tierra del Fuego provinces, Argentina, during 2013–2014 and 2014–2015 (>4600 km, 70 days) and review population trends of the Ruddy-headed Goose since the early 1900s. We counted a maximum of 19 individuals in Santa Cruz and 49 in Tierra del Fuego throughout the breeding season. A literature review indicates that during the last 40 years the size of continental population of Ruddy-headed Goose has been < 800 individuals, approximately 10% of the estimated population in the 1900s. This decline matches the period following the application of control techniques and the introduction of exotic predator species in the breeding grounds of Tierra del Fuego. We review and discuss formerly proposed conservation actions that may have a positive and rapid effect on sheldgoose numbers recovery. We suggest that the continental population of Ruddy-headed Goose should on a precautionary basis be treated as a critically endangered population until genetic studies determine whether we are in the presence of a new ‘Critically Endangered’ species.

Spatial and temporal variation in the migration of Ruddy-headed Goose in southern South America using satellite tagging

2020 ◽  
Vol 30 (4) ◽  
pp. 634-648
Author(s):  
JULIETA PEDRANA ◽  
KLEMENS PÜTZ ◽  
LUCÍA BERNAD ◽  
SEBASTIÁN MUÑOZ ◽  
ANTONELLA GOROSÁBEL ◽  
...  
Keyword(s):  
Autumn Migration ◽  
Current Status ◽  
Spatial And Temporal Variation ◽  
Factors Affecting ◽  
Migration Timing ◽  
Final Destination ◽  
Continental Population ◽  
Southern Patagonia ◽  
Breeding Grounds ◽  
Satellite Tagging

SummaryRuddy-headed Goose Chloephaga rubidiceps is the smallest of the five South American sheldgeese and has two separate populations: one sedentary, which resides in the Malvinas/Falkland Islands and one migratory that overwinters mainly in the Pampas region, Argentina and breeds in Southern Patagonia. The Ruddy-headed Goose’s continental population has decreased considerably, and recent estimates indicated that the population size is less than 800 individuals. In Argentina and Chile, this population is categorised as endangered. Understanding migration across vast landscapes is essential for the identification of factors affecting the survival of this endangered population and for the application of effective conservation measures. We aim to provide the first documentation of the complete migration cycle of Ruddy-headed Goose, and to analyse their annual migration in detail, including identification of stop-over, breeding and wintering sites, and to compare migration timing during spring and autumn migration. Adults were captured in the southern Pampas and equipped with solar satellite transmitters in 2015 and 2016. We analysed the influence of season (spring vs autumn migration) on the number and duration of stop-overs, distance travelled and overall migration speed using Generalized Linear Mixed Models. Our results showed that tracked geese used the eastern Patagonian route to reach their breeding grounds and take the same route after breeding. Spring migration was significantly faster than autumn migration, at least based on the number of days spent in their stop-overs. Stop-overs were closer to the final destination, either during spring and autumn migrations, though some of them were not used during subsequent migrations. Our migration cartography for Ruddy-headed Geese, together with the timing and location data, should be used to improve conservation efforts directed at this species and might contribute to the modification of the current status of ‘Least Concern’ under the IUCN criteria.

scholarly journals Declines in Wintering Populations of Red Knots in Southern South America

The Condor ◽  
2004 ◽  
Vol 106 (1) ◽  
pp. 60-70 ◽  
Author(s):  
R. I. Guy Morrison ◽  
R. Kenyon Ross ◽  
Lawrence J. Niles
Keyword(s):  
Population Decline ◽  
Food Resource ◽  
Limulus Polyphemus ◽  
Tierra Del Fuego ◽  
Calidris Canutus ◽  
The North ◽  
Dramatic Decline ◽  
Breeding Grounds ◽  
Wintering Areas ◽  
Key Sites

AbstractSurveys of the North American race of the Red Knot (Calidris canutus rufa) on its main wintering areas on the coasts of Patagonia and Tierra del Fuego (Argentina and Chile) showed a dramatic decline in the wintering population: totals in 2003 were about 30 000 compared to 67 500 in the mid-1980s. Numbers at the principal wintering site, Bahia Lomas, fell by approximately 50%, from 45 300 in 2000 to 22 000–25 000 in 2002–2003. Numbers at peripheral sites on the coast of Patagonia declined dramatically, decreasing 98% compared to numbers in the mid-1980s. The results showed that declines at core sites did not result from birds moving to other places within the known wintering (or other) areas, but reflected a general population decline, with most birds now restricted to key sites in Tierra del Fuego. This phenomenon may explain why long-term declines noted elsewhere have only recently become apparent at key wintering areas. Possible reasons for the declines are discussed. Banding studies in Delaware Bay have shown that in recent years an increasing proportion of Red Knots is unable to gain sufficient weight for migration to the breeding grounds. This is likely due to reductions in their main food resource, eggs of the horseshoe crab Limulus polyphemus. The resulting increase in mortality could account for the magnitude and severity of the declines we observed.Disminuciones en las Poblaciones Invernantes de Calidris canutus rufa en el Sur de Sur AméricaResumen. Censos de la raza norteamericana de Calidris canutus (rufa) en sus áreas de invernada principales en las costas de la Patagonia y Tierra del Fuego (Argentina y Chile) mostraron una disminución dramática en la población invernante. Los totales en 2003 fueron aproximadamente 30 000, comparados con 67 500 a mediados de los años 80. Los números en el sitio principal de invernada (Bahía Lomas) decayeron en aproximadamente un 50%, de 45 300 en 2000 a 22 000–25 000 en 2002–2003. Los números en sitios periféricos en la costa de Patagonia declinaron dramáticamente, en un 98% en comparación con los números de mediados de los ochenta. Los resultados mostraron que las disminuciones en los sitios núcleo no fueron el resultado de que las aves se movieran a otros sitios dentro del rango invernal conocido, o a otras áreas. En cambio, reflejaron una disminución general de la población; la mayoría de las aves están ahora restringidas a sitios claves en Tierra del Fuego. Este fenómeno podría explicar por qué las disminuciones poblacionales de largo plazo detectadas en otros lugares sólo se han hecho aparentes ahora en las áreas claves de invernada. Se discuten las posibles causas de las disminuciones. Estudios de anillamiento en la bahía de Delaware han mostrado que en años recientes una mayor proporción de las aves es incapaz de incrementar su peso hasta los niveles necesarios para la migración hacia las áreas de invernada. Esto probablemente es debido a reducciones en su principal recurso alimenticio, los huevos de Limulus polyphemus. El incremento en mortalidad resultante podría explicar la magnitud y la severidad de las disminuciones poblacionales que observamos.

Renewing hope: the rediscovery of Atelopus varius in Costa Rica

2013 ◽  
Vol 34 (4) ◽  
pp. 573-578 ◽  
Author(s):  
José F. González-Maya ◽  
Jerrold L. Belant ◽  
Sarah A. Wyatt ◽  
Jan Schipper ◽  
Josué Cardenal ◽  
...  
Keyword(s):  
Costa Rica ◽  
Resource Use ◽  
Private Property ◽  
Breeding Population ◽  
Critically Endangered ◽  
Single Location ◽  
Frog Species ◽  
Conservation Actions ◽  
Remnant Population ◽  
Protected Zone

More than 90% of harlequin frog species (Atelopus spp.), endemic to the Americas, are currently threatened with extinction. We report the discovery of the only currently known breeding population of the Critically Endangered A. varius in Costa Rica. This population was located in 2008 on a private property in Las Tablas Protected Zone near San Vito, Coto Brus at 1300 m elevation. Previously, the only known remaining/remnant population of this species and genus was a single location near Manuel Antonio, Puntarenas, Costa Rica, where two individuals were documented in 2004. Subsequent searches at this location have yielded no additional sightings. Delineating the spatial limits of this population, quantifying demographics and resource use, and implementing conservation actions are necessary to ensure persistence of this population. Conducting additional surveys in this region to ascertain occurrence of additional populations is warranted.

scholarly journals Novel methods reveal shifts in migration phenology of barn swallows in South Africa

2011 ◽  
Vol 279 (1733) ◽  
pp. 1485-1490 ◽  
Author(s):  
Res Altwegg ◽  
Kristin Broms ◽  
Birgit Erni ◽  
Phoebe Barnard ◽  
Guy F. Midgley ◽  
...  
Keyword(s):  
South Africa ◽  
Breeding Season ◽  
Environmental Variability ◽  
Southern Oscillation ◽  
Bird Species ◽  
Breeding Population ◽  
Migratory Bird ◽  
Recent Climate ◽  
Breeding Grounds ◽  
Barn Swallows

Many migratory bird species, including the barn swallow ( Hirundo rustica ), have advanced their arrival date at Northern Hemisphere breeding grounds, showing a clear biotic response to recent climate change. Earlier arrival helps maintain their synchrony with earlier springs, but little is known about the associated changes in phenology at their non-breeding grounds. Here, we examine the phenology of barn swallows in South Africa, where a large proportion of the northern European breeding population spends its non-breeding season. Using novel analytical methods based on bird atlas data, we show that swallows first arrive in the northern parts of the country and gradually appear further south. On their north-bound journey, they leave South Africa rapidly, resulting in mean stopover durations of 140 days in the south and 180 days in the north. We found that swallows are now leaving northern parts of South Africa 8 days earlier than they did 20 years ago, and so shortened their stay in areas where they previously stayed the longest. By contrast, they did not shorten their stopover in other parts of South Africa, leading to a more synchronized departure across the country. Departure was related to environmental variability, measured through the Southern Oscillation Index. Our results suggest that these birds gain their extended breeding season in Europe partly by leaving South Africa earlier, and thus add to scarce evidence for phenology shifts in the Southern Hemisphere.

scholarly journals Census of the Southern Giant Petrel population of the Falkland Islands 2004/2005

2008 ◽  
Vol 18 (2) ◽  
pp. 118-128 ◽  
Author(s):  
Tim A. Reid ◽  
Nic Huin
Keyword(s):  
Total Population ◽  
Current Knowledge ◽  
Conservation Status ◽  
Breeding Population ◽  
Knowledge Development ◽  
Falkland Islands ◽  
Giant Petrel ◽  
Strong Indication ◽  
Southern Giant Petrel ◽  
Near Threatened

AbstractA complete census was taken of all colonies of Southern Giant Petrels Macronectes giganteus within the Falkland Islands in 2004/05. The breeding population of the islands was estimated to be approximately 19,529 pairs (range 18,420–20,377). Southern Giant Petrels were found to breed in 38 locations around the islands, with colony size varying from one to 10,936. The majority of colonies were concentrated around the south of Falkland Sound, and to the west of West Falkland. Whilst there has been no previous census of the total population of the islands, there is a strong indication that the population has increased since the 1950s. The reasons for such an increase in population remain unclear in light of current knowledge. Development of our understanding of the breeding biology and demography of this species in the Falkland Islands is necessary, as is the need to conduct such a census every five years, with a few key colonies to be monitored every season. From the results obtained here, the conservation status of the Southern Giant Petrel, currently listed as ‘Vulnerable’, could be downgraded to ‘Near Threatened’.

Age, sex and status of wandering albatrosses Diomedea exulans L. in Falkland Islands waters

1999 ◽  
Vol 11 (2) ◽  
pp. 150-156 ◽  
Author(s):  
J.P. Croxall ◽  
A.D. Black ◽  
A.G. Wood
Keyword(s):  
Full Range ◽  
Polar Front ◽  
Breeding Birds ◽  
Falkland Islands ◽  
Antarctic Polar Front ◽  
South Georgia ◽  
Patagonian Shelf ◽  
Fishing Vessels ◽  
Shelf Slope ◽  
Breeding Grounds

Records (by a scientific observer on a longline fishing vessel around the Falkland Islands) of 86 different individually colour-banded wandering albatrosses from South Georgia, provide new insights into the use of the waters of the Patagonian shelf slope by birds from breeding grounds some 600 km to the south-east across the Antarctic Polar Front. Birds recorded were aged from 3–39 years, almost the full range (except 1 and 2 year olds) of South Georgia colour-banded birds, about 5% of whose colour-banded population was observed during the study. Immature birds (up to age 7 years) formed only 9% of the total; this may reflect relative absence from the area but might also relate to their subordinate status to adults at fishing vessels. Most birds seen were current breeders at South Georgia, including both sexes in the month prior to arrival on the breeding grounds (October), females during the pre-laying exodus (December) and both sexes during incubation (January) and throughout the main chick-rearing period (May, June, October). Only birds which had already failed were seen in the brooding period (March–April), when foraging trips are too short to reach the Falklands. Females outnumbered males in all these categories, supporting suggestions of different distributions of the sexes at sea during breeding. Birds of both sexes that had bred at South Georgia in the previous year were seen mainly between January and April. Birds that had not bred for at least three years were mainly males and mainly seen in January. These data indicate the importance of the waters near the Patagonian Shelf, especially around the Falklands, for wandering albatrosses from South Georgia, particularly breeding birds but also birds in their year(s) between breeding attempts. This is of particular relevance, given the globally threatened status of the species and the possibility of hydrocarbon exploitation in waters around the Falklands.

scholarly journals Description of Antho (Plocamia) bremecae sp. nov. and checklist of Microcionidae (Demospongiae: Poecilosclerida) from Burdwood Bank and neighboring areas, SW Atlantic Ocean 

Zootaxa ◽  
2017 ◽  
Vol 4312 (3) ◽  
pp. 580 ◽  
Author(s):  
SCHEJTER LAURA ◽  
BERTOLINO MARCO ◽  
CALCINAI BARBARA
Keyword(s):  
Atlantic Ocean ◽  
Tierra Del Fuego ◽  
Falkland Islands ◽  
The West ◽  
South Georgia ◽  
The North ◽  
Sw Atlantic ◽  
Scotia Arc ◽  
First Time ◽  
Burdwood Bank

In this contribution, we describe a new Demospongiae species, Antho (Plocamia) bremecae sp. nov., from the west slope of Burdwood bank, a poorly studied region in the SW Atlantic Ocean. We also recorded for the first time in the region two other microcionid species, Clathria (Axosuberites) nidificata and Clathria (Microciona) antarctica. In addition, a regional checklist of Microcionidae from Burdwood Bank and neighboring areas, including Malvinas (Falkland) Islands, Tierra del Fuego Province and the North of the Scotia Arc (South Georgia and Shag Rocks) is provided. 

scholarly journals Population size, distribution and status of the remote and Critically Endangered Bawean deer Axis kuhlii

Oryx ◽  
2016 ◽  
Vol 51 (4) ◽  
pp. 665-672 ◽  
Author(s):  
Dede Aulia Rahman ◽  
Georges Gonzalez ◽  
Stéphane Aulagnier
Keyword(s):  
Population Size ◽  
Faecal Pellet ◽  
Iucn Red List ◽  
Critically Endangered ◽  
Density Estimates ◽  
Distribution Maps ◽  
Population Size Estimates ◽  
Endangered Status ◽  
Size Estimates ◽  
Model Approach

AbstractConservation of rare ungulates requires reliable population size estimates and distribution maps for prioritizing investments and assessing the effectiveness of conservation measures. We used both camera trapping and a random encounter model approach, and faecal pellet group counts, to update the range and population size of the Bawean deer Axis kuhlii in the Bawean Island Nature Reserve and Wildlife Sanctuary, Indonesia. We studied 2-month periods to fulfil the assumption of population closure. Both methods provided similar population density estimates (higher in the dry season) of c. 227–416 individuals. The estimated range of the species is significantly narrower than previously reported. The main threats (habitat loss as a result of illegal logging, and disturbance by dogs and hunters) are ongoing. Based on these results we suggest that the species should retain its Critically Endangered status on the IUCN Red List.

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