Stanley, Falkland Islands
Stanley, Falkland Islands

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Rexer-Huber K.,Stanley Inc. | Parker G.C.,Stanley Inc. | Reeves M.,Falklands Conservation | Stanworth A.J.,Falklands Conservation | Cuthbert R.J.,Royal Society for the Protection of Birds
Polar Biology | Year: 2013

Invasive house mice Mus musculus are known to impact on seabird, invertebrate and plant communities on temperate and subantarctic islands, particularly where they are the sole rodent species. Steeple Jason, in the Falkland Islands, is an island which supports globally important seabird populations as well as introduced mice. To evaluate the prospects for mouse eradication, we investigated mouse ecology and undertook bait uptake trials on Steeple Jason in late winter. Mice were present in all habitats but were most abundant in tussac Poa flabellata where they occurred at 20-35 mice ha-1. From 58 mature perforate females, 16 % were pregnant, with litters of 4-8 pups. The first lactating female was caught at the end of August, suggesting that breeding had recently begun. Bait trials replicating an aerial eradication were undertaken on two trapping grids of 7.7 and 6.8 ha, with non-toxic pellets containing the biomarker pyranine spread at 7.5-7.7 kg ha-1. All 447 mice captured after baiting had consumed bait. The relatively low winter density, distribution and biology of house mice on Steeple Jason are similar to those observed before other successful mice eradications, and the study indicated 100 % bait acceptance. Before an eradication attempt, we suggest investigating whether breeding ceases completely earlier in the winter and urge careful consideration of non-target species. © Springer-Verlag Berlin Heidelberg 2013.

Wakefield E.D.,Natural Environment Research Council | Phillips R.A.,Natural Environment Research Council | Trathan P.N.,Natural Environment Research Council | Arata J.,Instituto Antartico Chileno | And 6 more authors.
Ecological Monographs | Year: 2011

Telemetry methods and remote sensing now make it possible to record the spatial usage of wide-ranging marine animals and the biophysical characteristics of their pelagic habitats. Furthermore, recent statistical advances mean that such data can be used to test ecological hypotheses and estimate species' distributions. Black-browed Albatrosses Thalassarche melanophrys are highly mobile marine predators with a circumpolar breeding and foraging distribution in the Southern Hemisphere. Although they remain relatively abundant, increased fisheries bycatch has led to their listing as endangered by conservation bodies. We satellite-tracked 163 breeding Black-browed Albatrosses and eight closely related Campbell Albatrosses T. impavida from nine colonies. We then quantified habitat usage, and modeled population-level spatial distribution at spatiotemporal scales >50 km and 1 month, as a function of habitat accessibility, habitat preference, and intraspecific competition, using mixed-effects generalized additive models (GAMM). During incubation, birds foraged over a wider area than in the post-brood chick-rearing period, when they are more time constrained. Throughout breeding, the order of habitat preference of Black-browed Albatrosses was for neritic (0-500 m), shelf-break and upper shelf-slope (500-1000 m), and then oceanic (>1000 m) waters. Black-browed Albatrosses also preferred areas with steeper (>3°) bathymetric relief and, in addition, during incubation, warmer sea surface temperatures (peak preference ∼16°C). Although this suggests specialization in neritic habitats, incubation-stage Blackbrowed Albatrosses from South Georgia also foraged extensively in oceanic waters, preferring areas with high eddy kinetic energy (>250 cm2/s2), especially the Brazil-Malvinas Confluence, a region of intense mesoscale turbulence. During chick-rearing, this species had a more southerly distribution, and following the seasonal retreat of sea ice, birds from some populations utilized neritic polar waters. Campbell Albatrosses showed similar bathymetric preferences but also preferred positive sea level anomalies. Black-browed Albatross foraging areas were partially spatially segregated with respect to colony and region, with birds preferring locations distant from neighboring colonies, presumably in order to reduce competition between parapatric conspecifics. At the global scale, the greatest concentrations of breeding Black-browed Albatrosses are in southern South American neritic, shelf-break, and shelf-slope waters. These regions also hold large fisheries and should therefore be a priority for introduction of bycatch mitigation measures. © 2011 by the Ecological Society of America.

Baylis A.M.M.,Deakin University | Crofts S.,Falklands Conservation | Wolfaardt A.C.,Joint Nature Conservation Committee
Marine Ornithology | Year: 2013

The fourth archipelago-wide census of Gentoo Penguins Pygoscelis papua breeding at the Falkland Islands was conducted from 24 October to 8 December 2010. The number of Gentoo Penguins breeding in 2010 was estimated to be 132 321 ± 2 015, the highest number of breeding pairs recorded for this species at the Falkland Islands since the first survey in 1933. The global population of Gentoo Penguins is conservatively estimated to be about 384 000 breeding pairs, of which the Falkland Islands accounts for 34%, probably the largest component of the global population. Annually monitored study colonies accounted for 20% of the total number of Gentoo Penguin breeding pairs at the Falkland Islands in 2010 and proved to be a reliable proxy for archipelago-wide changes in the number of breeding pairs. Recent trends at annually monitored study colonies, combined with archipelago-wide trends, indicate that the number of Gentoo Penguins breeding at the Falkland Islands has increased between 2005 to 2010. However, annual monitoring data also revealed large inter-annual variability in the number of breeding pairs, which makes assessing systematic population changes challenging.

Baylis A.M.M.,Falklands Conservation | Zuur A.F.,Highland Statistics Ltd | Zuur A.F.,University of Aberdeen | Brickle P.,Falkland Islands Government | Pistorius P.A.,Nelson Mandela Metropolitan University
Ibis | Year: 2012

Detecting and predicting how populations respond to environmental variability are eminent challenges in conservation research and management. This is particularly true for wildlife populations at high latitudes, many of which demonstrate changes in population dynamics associated with global warming. The Falkland Islands (Southwest Atlantic) hold one of the largest Gentoo Penguin Pygoscelis papua populations in the world, representing c. 34% of the global population. The numbers of breeding Gentoo Penguins at the Falkland Islands have shown a high degree of inter-annual variability since monitoring commenced in 1990. However, proximate causes of annual variability in breeding numbers have not been explored. Here we examine 21years of Gentoo Penguin breeding surveys from the Falkland Islands and assess whether inter-annual variability in the number of breeding pairs were correlated with proxies of environmental variability. There was a positive correlation between the number of breeding pairs and a broad-scale climatic variation index, the Southern Oscillation Index (SOI). In turn, the SOI was significantly correlated with spring sea surface temperature anomalies, indicating a more immediate atmospherically forced response to El Niño Southern Oscillation variability in the Southwest Atlantic than previously reported. However, we also describe a non-linear response to environmental variability that may highlight foraging plasticity and/or the complexity of regional ecosystem interactions that operate across a range of different scales. © 2011 The Authors. Ibis © 2011 British Ornithologists' Union.

Dwyer J.F.,EDM International Inc. | Cockwell S.G.,Falklands Conservation
Journal of Raptor Research | Year: 2011

On the Falkland Islands (Malvinas), raptors historically were perceived as a threat to livestock, and consequently were widely persecuted through the mid-twentieth century. Conservation measures now minimize persecution and have facilitated increases in raptor populations, but the ecology of raptors on the Falkland Islands (Malvinas) remains poorly understood. We investigated social hierarchies within an assemblage of nonmigratory raptorial scavengers: Variable Hawk (Buteo polyosoma), Striated Caracara (Phalcoboenus australis), Southern Caracara (Caracara plancus), and Turkey Vulture (Cathartes aura jota). During thirty observation sessions of 30 min each, we recorded 1386 aggressive interactions involving one or more of these species. We found that Variable Hawks were aggressors in 98% (95% CI = 96-100%) of interactions with Striated Caracaras, 82% (69-95%) of interactions with Turkey Vultures, and 80% (72-88%) of interactions with Southern Caracaras. Southern Caracaras were aggressors in 100% of interactions with Striated Caracaras, and 90% (80-100%) of interactions with Turkey Vultures. Turkey Vultures were aggressors in 71% (61-82%) of interactions with Striated Caracaras. Within species, we found adult Southern Caracaras were aggressors in 78% (72-84%) of interactions with conspecific juveniles and 76% (68-85%) of interactions with conspecfic subadults. Adult Striated Caracaras were aggessors in 100% of interactions with conspecific juveniles and 97% (91-100%) of interactions with conspecfic subadults. Predicted patterns of size-based dominance typical of complex African and South American avian scavenger assemblages were not observed in the relatively simple assemblage of the Falkland Islands (Malvinas), but we did observe single-species groups of up to 83 Southern Caracaras and 42 Striated Caracaras. © 2011 The Raptor Research Foundation, Inc.

Pistorius P.A.,Nelson Mandela Metropolitan University | Baylis A.,Falklands Conservation | Crofts S.,Falklands Conservation | Putz K.,Antarctic Research Trust
Antarctic Science | Year: 2012

After an extended period of sporadic sightings of small numbers of king penguins at the Falkland Islands, they established themselves on Volunteer Point, situated at the north-east of the islands, by the late 1970s. By 1980, a small breeding population was present which yielded some 40 fledglings during that same year. Since 1991, the population has been monitored annually and the resulting fledgling counts analysed to assess population trends. The population demonstrated a significant increase over the past three decades, at about 10% per annum, with time explaining 75% of the variation in count data. The current population is estimated to be 720 breeding pairs. Despite several authors having alluded to the existence of a large colony of king penguins at the Falklands prior to human exploitation, we found no evidence in support of this. We furthermore found no evidence in the literature in support of exploitation for king penguin oil during the 19th century. Unlike at other breeding sites, increasing numbers of king penguins at the Falklands is consequently unlikely to be a recovery response following exploitation, but rather an indication of either increased immigration or of improved feeding conditions. © Copyright 2012 Antarctic Science Ltd.

Pistorius P.A.,Falklands Conservation | Crofts N.H.S.,Falklands Conservation
Marine Ornithology | Year: 2010

Data on population size and breeding success of Gentoo Penguins Pygoscelis papua at the Falkland Islands have been collected since 1990 as part of the Falkland Islands Seabird Monitoring Programme FISMP. During the austral summer of 2005/2006, the third five-yearly survey of all Gentoo Penguins breeding in the Falklands Archipelago was undertaken. Results are presented and compared to previous population estimates. The number of breeding pairs in 2005/2006 was estimated at 65,857, a decline of 42% since 2000, which was attributed largely to paralytic shellfish poisoning resulting from a harmful algal bloom event in 2002. Based on a selected number of colonies that were monitored annually, the population increased by over 95% since 2005, and numbered a record high of some 128,500 breeding pairs in 2008. On average, annual breeding success was 1.01 ranging between 0.51 and 1.44 chicks per breeding pair. Although no particular trend was evident, breeding success was above average between 2004 and 2008 which is likely to contribute towards future population growth.

Ochyra R.,Polish Academy of Sciences | Crabtree D.,Falklands Conservation | Tangney R.,National Museum of Wales
Cryptogamie, Bryologie | Year: 2015

Bucklandiella didyma (Mont.) Bednarek-Ochyra et Ochyra and Codriophorus laevigatus (Mitt.) Bednarek-Ochyra et Ochyra are recorded for the first time from the Falkland Islands. Bucklandiella heterostichoides (Cardot) Bednarek-Ochyra et Ochyra, B. membranacea (Mitt.) Bednarek-Ochyra et Ochyra and B. ptychophylla (Mitt.) Bednarek-Ochyra et Ochyra are newly reported from East Falkland and B. sudetica (Funck) Bednarek-Ochyra et Ochyra is a new addition to the bryoflora of We st Falkland. In total, seven species of Bucklandiella Roiv. are currently known from the Falkland Islands and they are briefly characterised, their geographical range is surveyed and global distribution of selected species is mapped. The status of five species of Bucklandiella which are excluded from the bryoflora of the archipelago is briefly considered. A key to determination of species of taxa of the Racomitrioideae in the Falkland Islands is presented. © 2015 Adac. Tous droits réservés.

Ratcliffe N.,British Antarctic Survey | Crofts S.,Falklands Conservation | Brown R.,British Antarctic Survey | Baylis A.M.M.,Falklands Conservation | And 6 more authors.
Journal of Biogeography | Year: 2014

Aim: Competition for food among populations of closely related species and conspecifics that occur in both sympatry and parapatry can be reduced by interspecific and intraspecific spatial segregation. According to predictions of niche partitioning, segregation is expected to occur at habitat boundaries among congeners and within habitats among conspecifics, while negative relationships in the density of species or populations will occur in areas of overlap. We tested these predictions by modelling the winter distributions of two crested penguin species from three colonies in the south-western Atlantic. Location: Penguins were tracked from two large colonies on the Falkland Islands and one in South Georgia, from where they dispersed through the South Atlantic, Southern Ocean and south-eastern Pacific. Methods: Forty macaroni penguins (Eudyptes chrysolophus) from South Georgia and 82 southern rockhopper penguins (Eudyptes chrysocome chrysocome) from two colonies in the Falkland Islands were equipped with global location sensors which log time and light, allowing positions to be estimated twice-daily, from April to August in 2011. Positions were gridded and converted into maps of penguin density. Metrics of overlap were calculated and density was related to remote-sensed oceanographic variables and competitor density using generalized additive models. Results: Macaroni penguins from western South Georgia and southern rockhopper penguins from Steeple Jason Island, Falkland Islands, were spatially segregated by differences in their habitat preferences thus supporting our first prediction regarding interspecific segregation. However, southern rockhopper penguins from Beauchêne Island showed a marked spatial overlap with macaroni penguins as the two had similar habitat preferences and strong mutual associations when controlling for habitat. Contrary to our predictions relating to intraspecific segregation, southern rockhopper penguins from Beauchêne Island and Steeple Jason Island were segregated by differences in habitat selection. Main conclusions: Morphological differentiation probably allows macaroni penguins from South Georgia and southern rockhopper penguins from Beauchêne Island to coexist in areas of spatial overlap, whereas segregation of the two Falkland rockhopper penguin populations may have arisen from two distinct lineages retaining cultural fidelity to ancestral wintering areas. © 2014 The Authors. Journal of Biogeography Published by John Wiley & Sons Ltd.

Baylis A.M.M.,Deakin University | Wolfaardt A.C.,Joint Nature Conservation Committee | Crofts S.,Falklands Conservation | Pistorius P.A.,Nelson Mandela Metropolitan University | Ratcliffe N.,British Antarctic Survey
Polar Biology | Year: 2013

The Falkland Islands currently supports one of the largest Southern Rockhopper Penguin (Eudyptes c. chrysocome) populations. Archipelago-wide censuses conducted in 2000 and 2005 revealed that the number of breeding pairs had declined by 30 % during this period. To establish whether the breeding population continued to decline, an archipelago-wide census was conducted in 2010. We report a conservative estimate of 319,163 ±SD 24,820 pairs breeding at the Falkland Islands in 2010. This represents a 51 % increase when compared with the number counted in 2005. A simple stochastic population model was developed to investigate the extent to which changes in demographic parameters between 2005 and 2010 could account for the increase in breeding pairs. The population model predicted a 38 % increase in the number of breeding pairs over a 5-year period (289,431 ±SD 24,615). The increase in the number of breeding pairs was therefore probably attributed to improved vital rates in the period between the 2005 and 2010 archipelago-wide censuses in combination with other factors such as a reduction in the proportion of adult birds that abstained from breeding. Based on the 2010 Falkland Islands estimate, the global population of the subspecies E. c. chrysocome is now closer to 870,000 breeding pairs of which the Falkland Islands accounts for approximately 36 %, the second largest proportion after Chile. We conclude that despite fluctuations, the number of Southern Rockhopper Penguins breeding at the Falkland Islands has increased over the last 15 years and suggest that the 'Vulnerable' conservation status of the species be re-assessed. © 2013 Springer-Verlag Berlin Heidelberg.

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