Population structure and historical demography of South American sea lions provide insights into the catastrophic decline of a marine mammal population

Understanding the causes of population decline is crucial for conservation management. We therefore used genetic analysis both to provide baseline data on population structure and to evaluate hypotheses for the catastrophic decline of the South American sea lion ( Otaria flavescens ) at the Falkland Islands (Malvinas) in the South Atlantic. We genotyped 259 animals from 23 colonies across the Falklands at 281 bp of the mitochondrial hypervariable region and 22 microsatellites. A weak signature of population structure was detected, genetic diversity was moderately high in comparison with other pinniped species, and no evidence was found for the decline being associated with a strong demographic bottleneck. By combining our mitochondrial data with published sequences from Argentina, Brazil, Chile and Peru, we also uncovered strong maternally directed population structure across the geographical range of the species. In particular, very few shared haplotypes were found between the Falklands and South America, and this was reflected in correspondingly low migration rate estimates. These findings do not support the prominent hypothesis that the decline was caused by migration to Argentina, where large-scale commercial harvesting operations claimed over half a million animals. Thus, our study not only provides baseline data for conservation management but also reveals the potential for genetic studies to shed light upon long-standing questions pertaining to the history and fate of natural populations.

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The impact of human activities on Australian wildlife

10.1101/452409 ◽

2018 ◽

Author(s):

Alyce Taylor-Brown ◽

Rosie Booth ◽

Amber Gillett ◽

Erica Mealy ◽

Steven Ogbourne ◽

...

Keyword(s):

Human Activities ◽

Large Scale ◽

Conservation Management ◽

Urban Expansion ◽

Population Decline ◽

Natural Populations ◽

Mortality Rates ◽

Natural Ecosystems ◽

Negative Impacts ◽

The Impact

AbstractIncreasing human population size and the concomitant expansion of urbanisation significantly impact natural ecosystems and native fauna globally. Successful conservation management relies on precise information on the factors associated with wildlife population decline, which are challenging to acquire from natural populations. Wildlife Rehabilitation Centres (WRC) provide a rich source of this information. However, few researchers have conducted large-scale longitudinal studies, with most focussing on narrow taxonomic ranges, suggesting that WRC-associated data remains an underutilised resource, and may provide a fuller understanding of the anthropogenic threats facing native fauna.We analysed admissions and outcomes data from a WRC in Queensland, Australia Zoo Wildlife Hospital, to determine the major factors driving admissions and morbidity of native animals in a region experiencing rapid and prolonged urban expansion.We studied 31,626 admissions of 83 different species of native birds, reptiles, amphibians, marsupials and eutherian mammals from 2006 to 2017. While marsupial admissions were highest (41.3%), admissions increased over time for all species and exhibited seasonal variation (highest in Spring to Summer), consistent with known breeding seasons.Causes for admission typically associated with human influenced activities were dominant and exhibited the highest mortality rates. Car strikes were the most common reason for admission (34.7%), with dog attacks (9.2%), entanglements (7.2%), and cat attacks (5.3% also high. Admissions of orphaned young and overt signs of disease were significant at 24.6% and 9.7%, respectively. Mortality rates were highest following dog attacks (72.7%) and car strikes (69.1%) and lowest in orphaned animals (22.1%).Our results show that WRC databases offer rich opportunities for wildlife monitoring and provide quantification of the negative impacts of human activities on ecosystem stability and wildlife health. The imminent need for urgent, proactive conservation management to ameliorate the negative impacts of human activities on wildlife is clearly evident from our results.

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POPULATION STRUCTURE AND PRODUCTION OF COPAIBA OLEORESIN BETWEEN VALLEYS AND HILLSIDES OF THE MINING AREA OFTROMBETAS RIVER - PARÁ1

Revista Árvore ◽

10.1590/0100-67622016000100006 ◽

2016 ◽

Vol 40 (1) ◽

pp. 51-60 ◽

Cited By ~ 2

Author(s):

Jonas Gebara ◽

Antenor Pereira Barbosa ◽

Isabel Maria Gonçalves Azevedo ◽

Bruno Oliva Gimenez

Keyword(s):

Population Structure ◽

Forest Inventory ◽

Sustainable Management ◽

Natural Populations ◽

Mining Area ◽

National Forest ◽

The South ◽

Potential Production ◽

Average Value ◽

Bauxite Ore

ABSTRACT We aimed in this work to study natural populations of copaiba (Copaifera multijuga Hayne) on the Monte Branco mountain at Porto Trombetas-PA, in order to support sustainable management and the exploitation of oleoresin from copaiba. We studied the population structure of copaiba on hillsides and valleys of the south face of Monte Branco, within Saracá Taquera National Forest, where bauxite ore was extracted in the biennium 2013-2014 by Mineração Rio do Norte (MRN). We produced a 100% forest inventory of the specie and of oleoresin extraction in order to quantify the potential production of the remaining area. The density of copaiba individuals with DBH > 30 cm was 0.33 individuals per hectare in the hillside and 0.25 individuals per hectare in the valley. Both environments presented a density of 0.28 individuals per hectare. The average copaiba oleoresin yield was 0.661±0.334 liters in the hillside and 0.765±0.280 liters in the valley. The average value of both environments together (hillside and valley) was 0.714±0.218 liters. From all individuals with DBH over 30 cm, 38 (58%) produced some amount of oleoresin, averaging 1.113±0.562 liters in the hillside, 1.329±0.448 liters in the valley and 1.190±0.355 liters in both environments together. The results show the need for planning the use of the surroundings of the study area in order to reach the required volume of copaiba to make feasible the sustainable management of oleoresin extraction in the region.

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Centennial-scale precipitation anomalies in the southern Altiplano (18° S) suggest an extratropical driver for the South American summer monsoon during the late Holocene

Climate of the Past ◽

10.5194/cp-15-1845-2019 ◽

2019 ◽

Vol 15 (5) ◽

pp. 1845-1859 ◽

Cited By ~ 2

Author(s):

Ignacio A. Jara ◽

Antonio Maldonado ◽

Leticia González ◽

Armand Hernández ◽

Alberto Sáez ◽

...

Keyword(s):

Summer Monsoon ◽

Large Scale ◽

Southern Oscillation ◽

Atlantic Coast ◽

Austral Summer ◽

High Elevation ◽

South American ◽

Tropical Andes ◽

The South ◽

Precipitation Anomalies

Abstract. Modern precipitation anomalies in the Altiplano, South America, are closely linked to the strength of the South American summer monsoon (SASM), which is influenced by large-scale climate features sourced in the tropics such as the Intertropical Convergence Zone (ITCZ) and El Niño–Southern Oscillation (ENSO). However, the timing, direction, and spatial extent of precipitation changes prior to the instrumental period are still largely unknown, preventing a better understanding of the long-term drivers of the SASM and their effects over the Altiplano. Here we present a detailed pollen reconstruction from a sedimentary sequence covering the period between 4500 and 1000 cal yr BP in Lago Chungará (18∘ S; 4570 m a.s.l.), a high-elevation lake on the southwestern margin of the Altiplano where precipitation is delivered almost exclusively during the mature phase of the SASM over the austral summer. We distinguish three well-defined centennial-scale anomalies, with dry conditions between 4100–3300 and 1600–1000 cal yr BP and a conspicuous humid interval between 2400 and 1600 cal yr BP, which resulted from the weakening and strengthening of the SASM, respectively. Comparisons with other climate reconstructions from the Altiplano, the Atacama Desert, the tropical Andes, and the southwestern Atlantic coast reveal that – unlike modern climatological controls – past precipitation anomalies at Lago Chungará were largely decoupled from north–south shifts in the ITCZ and ENSO. A regionally coherent pattern of centennial-scale SASM variations and a significant latitudinal gradient in precipitation responses suggest the contribution of an extratropical moisture source for the SASM, with significant effects on precipitation variability in the southern Altiplano.

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The large-scale upper circulation during the main rainy season of wet and dry years above the South American Altiplano

Meteorologische Zeitschrift ◽

10.1127/metz/1/1992/276 ◽

1992 ◽

Vol 1 (6) ◽

pp. 276-284 ◽

Cited By ~ 5

Author(s):

J. Jacobeit

Keyword(s):

Rainy Season ◽

Large Scale ◽

South American ◽

The South ◽

Main Rainy Season

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Decadal Variability in the Large-Scale Sea Surface Height Field of the South Pacific Ocean: Observations and Causes

Journal of Physical Oceanography ◽

10.1175/jpo2943.1 ◽

2006 ◽

Vol 36 (9) ◽

pp. 1751-1762 ◽

Cited By ~ 71

Author(s):

Bo Qiu ◽

Shuiming Chen

Keyword(s):

Pacific Ocean ◽

Rossby Wave ◽

Large Scale ◽

South Pacific ◽

Sea Surface Height ◽

Sea Surface ◽

South American ◽

The South ◽

South Pacific Ocean ◽

Spatially Varying

Abstract Large-scale sea surface height (SSH) changes in the extraequatorial South Pacific Ocean are investigated using satellite altimetry data of the past 12 yr. The decadal SSH signals in the 1990s were dominated by an increasing trend in the 30°–50°S band and a decreasing trend in the central South Pacific Ocean poleward of 50°S. In recent years since 2002 there has been a reversal in both of these trends. Spatially varying low-frequency SSH signals are also found in the tropical region of 10°–25°S where the decadal SSH trend is negative in the eastern basin, but positive in the western basin. To clarify the causes for these observed spatially varying SSH signals, a 1½-layer reduced-gravity model that includes the wind-driven baroclinic Rossby wave dynamics and the responses forced by SSH changes along the South American coast was adopted. The model hindcasts the spatially varying decadal trends in the midlatitude and the eastern tropical regions well. Accumulation of the wind-forced SSH anomalies along Rossby wave characteristics is found to be important for both previously reported long-term trends and their reversals in recent years. The boundary forcing associated with the time-varying SSH signals along the South American coast is crucial for understanding the observed SSH signals of all time scales in the eastern tropical South Pacific basin, but it has little impact upon the midlatitude interior SSH signals.

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Genetic Diversity and Population Structure Revealed by SSR Markers on Endemic Species Osmanthus serrulatus Rehder from Southwestern Sichuan Basin, China

Forests ◽

10.3390/f12101365 ◽

2021 ◽

Vol 12 (10) ◽

pp. 1365

Author(s):

Lin Chen ◽

Tingting Pan ◽

Huirong Qian ◽

Min Zhang ◽

Guodong Yang ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Ssr Markers ◽

Sichuan Basin ◽

Polymorphic Information Content ◽

Population Decline ◽

Natural Populations ◽

Genetic Population ◽

Endangered Status ◽

High Level

Osmanthus serrulatus Rehder (Oleaceae) is an endemic spring-flowering species in China. It is narrowly distributed in the southwestern Sichuan Basin, and is facing the unprecedented threat of extinction due to problems associated with natural regeneration, habitat fragmentation and persistent and serious human interference. Here, the genetic diversity and population structure of 262 individuals from ten natural populations were analyzed using 18 microsatellites (SSR) markers. In total, 465 alleles were detected across 262 individuals, with a high polymorphic information content (PIC = 0.893). A high level of genetic diversity was inferred from the genetic diversity parameters (He = 0.694, I = 1.492 and PPL = 98.33%). AMOVA showed that a 21.55% genetic variation existed among populations and the mean pairwise Fst (0.215) indicated moderate genetic population differentiation. The ten populations were basically divided into three groups, including two obviously independent groups. Our results indicate that multiple factors were responsible for the complicated genetic relationship and endangered status of O. serrulatus. The concentrated distribution seems to be the key factor causing endangerment, and poor regeneration, human-induced habitat loss and fragmentation seem to be the primary factors in the population decline and further genetic diversity loss. These findings will assist in future conservation management and the scientific breeding of O. serrulatus.

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Daily Precipitation Statistics for South America: An Intercomparison between NCEP Reanalyses and Observations

Journal of Hydrometeorology ◽

10.1175/2010jhm1303.1 ◽

2011 ◽

Vol 12 (1) ◽

pp. 101-117 ◽

Cited By ~ 33

Author(s):

Viviane B. S. Silva ◽

Vernon E. Kousky ◽

R. Wayne Higgins

Keyword(s):

South America ◽

Large Scale ◽

Atmospheric Model ◽

Northeastern Brazil ◽

South American ◽

The South ◽

Wet Season ◽

Central Brazil ◽

Monsoon System ◽

Dry Bias

Abstract In this study, the authors document the extent to which the precipitation statistics of the new CFS reanalysis (CFSR) represent an improvement over the earlier reanalyses: the NCEP–NCAR reanalysis (R1) and the NCEP–DOE Second Atmospheric Model Intercomparison Project (AMIP-II) reanalysis (R2). An intercomparison between the CFSR, R1, R2, and observations over South America was made for the period 1979–2006. The CFSR shows notable improvements in the large-scale precipitation patterns compared with the previous reanalyses (R1 and R2). In spite of these improvements, the CFSR has substantial biases in intensity and frequency of occurrence of rainfall events. Over west-central Brazil, the core region of the South American monsoon system (SAMS), the CFSR displays a dry bias during the onset phase of the SAMS wet season and a wet bias during the peak and decay phases of the SAMS wet season. The CFSR also displays a dry bias along the South American coast near the mouth of the Amazon and along the east coast of northeastern Brazil. A wet bias exists in all seasons over southeast Brazil and over the Andes Mountains.

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Population Structure of mtDNA Variation due to Pleistocene Fluctuations in the South American Maned Wolf (Chrysocyon brachyurus, Illiger, 1815): Management Units for Conservation

Journal of Heredity ◽

10.1093/jhered/esv043 ◽

2015 ◽

Vol 106 (S1) ◽

pp. 459-468 ◽

Cited By ~ 6

Author(s):

Susana González ◽

Mariana Cosse ◽

María del Rosario Franco ◽

Louise Emmons ◽

Carly Vynne ◽

...

Keyword(s):

Population Structure ◽

South American ◽

The South ◽

Management Units ◽

Mtdna Variation ◽

Maned Wolf ◽

Chrysocyon Brachyurus

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Precipitation Characteristics of the South American Monsoon System Derived from Multiple Datasets

Journal of Climate ◽

10.1175/jcli-d-11-00335.1 ◽

2012 ◽

Vol 25 (13) ◽

pp. 4600-4620 ◽

Cited By ~ 33

Author(s):

Leila M. V. Carvalho ◽

Charles Jones ◽

Adolfo N. D. Posadas ◽

Roberto Quiroz ◽

Bodo Bookhagen ◽

...

Keyword(s):

South America ◽

Large Scale ◽

Austral Summer ◽

Global Precipitation Climatology Project ◽

South American ◽

The South ◽

Frequency Distributions ◽

South American Monsoon ◽

Monsoon System ◽

South American Monsoon System

Abstract The South American monsoon system (SAMS) is the most important climatic feature in South America and is characterized by pronounced seasonality in precipitation during the austral summer. This study compares several statistical properties of daily gridded precipitation from different data (1998–2008): 1) Physical Sciences Division (PSD), Earth System Research Laboratory [1.0° and 2.5° latitude (lat)/longitude (lon)]; 2) Global Precipitation Climatology Project (GPCP; 1° lat/lon); 3) Climate Prediction Center (CPC) unified gauge (CPC-uni) (0.5° lat/lon); 4) NCEP Climate Forecast System Reanalysis (CFSR) (0.5° lat/lon); 5) NASA Modern-Era Retrospective Analysis for Research and Applications (MERRA) reanalysis (0.5° lat/0.3° lon); and 6) Tropical Rainfall Measuring Mission (TRMM) 3B42 V6 data (0.25° lat/lon). The same statistical analyses are applied to data in 1) a common 2.5° lat/lon grid and 2) in the original resolutions of the datasets. All datasets consistently represent the large-scale patterns of the SAMS. The onset, demise, and duration of SAMS are consistent among PSD, GPCP, CPC-uni, and TRMM datasets, whereas CFSR and MERRA seem to have problems in capturing the correct timing of SAMS. Spectral analyses show that intraseasonal variance is somewhat similar in the six datasets. Moreover, differences in spatial patterns of mean precipitation are small among PSD, GPCP, CPC-uni, and TRMM data, while some discrepancies are found in CFSR and MERRA relative to the other datasets. Fitting of gamma frequency distributions to daily precipitation shows differences in the parameters that characterize the shape, scale, and tails of the frequency distributions. This suggests that significant uncertainties exist in the characterization of extreme precipitation, an issue that is highly important in the context of climate variability and change in South America.

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