Behavioural and oceanographic isolation of an island-based jellyfish (Copula sivickisi, Class Cubozoa) population

AbstractCubozoan jellyfish are classified as plankton despite the strong swimming and orientation abilities of cubomedusae. How these capabilities could affect cubozoan population structures is poorly understood. Medusae of the cubozoan Copula sivickisi can uniquely attach to surfaces with the sticky pads on their bells. Biophysical modelling was used to investigate the spatial scales of connectivity in a C. sivickisi population. When the medusae were active at night they could maintain their observed distribution on fringing reef if they attached to the reef when the current speed exceeded a moderate threshold. This behaviour facilitated the isolation of a C. sivickisi population on reefs fringing Magnetic Island, Queensland, Australia. Within this distribution, there was considerable within bay retention and medusae rarely travelled > 3 km. The few (< 0.1%) medusae lost from the island habitat were largely advected into open water and away from the mainland coast which lies 8 km from the island. Given that successful emigration is unlikely, the island population probably represents a stock that is ecologically distinct from any mainland populations. The cosmopolitan distribution of C. sivickisi could contain incipient or cryptic species given the small scales of connectivity demonstrated here.

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Co-occurring cryptic species pose challenges for conservation: a case study of the African dwarf crocodile (Osteolaemusspp.) in Cameroon

Oryx ◽

10.1017/s0030605314000647 ◽

2014 ◽

Vol 49 (4) ◽

pp. 584-590 ◽

Cited By ~ 3

Author(s):

Nicole L. Smolensky

Keyword(s):

Cryptic Species ◽

Conservation Status ◽

Taxonomic Revision ◽

Single Species ◽

Conservation Strategies ◽

Encounter Rates ◽

Distribution Maps ◽

Species Complexes ◽

Threatened Taxa ◽

Population Structures

AbstractThe conservation status of threatened taxa may be obfuscated by the detection of cryptic species complexes, in both vertebrate and invertebrate species. African dwarf crocodiles (Osteolaemusspp.) are hunted throughout their range but their conservation status is unknown. Few population assessments have been carried out and there has been a taxonomic revision of the number of species in the genus. The similar morphologies ofOsteolaemus tetraspisandOsteolaemus osbornipose a challenge for conservation in Cameroon, where they are still managed as a single species. Nocturnal spotlight surveys were conducted in three regions during August–November 2010 and December 2011–February 2012 to provide population assessments ofO. tetraspisandO. osborniand raise awareness of the two species in Cameroon. The mean encounter rates ofO. tetraspisandO. osborniwere 1.02 ± SD 1.34 (65 individuals in 39 surveys) and 0.61 ± SD 0.38 (three in four surveys) crocodiles per km, respectively. TheO. tetraspispopulation comprised juveniles predominantly and had a male-biased sex ratio. The fewO. osbornidetected comprised both adults and juveniles. Both species are threatened in Cameroon, based on low encounter rates, young population structures and the threats of habitat loss and hunting pressure. This study provides distribution maps and serves as a baseline to quantify population trends and inform conservation strategies.

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E-DATA: A Comprehensive Field Campaign to Investigate Evaporation Enhanced by Advection in the Hyper-Arid Altiplano

Water ◽

10.3390/w12030745 ◽

2020 ◽

Vol 12 (3) ◽

pp. 745 ◽

Cited By ~ 1

Author(s):

Francisco Suárez ◽

Felipe Lobos ◽

Alberto de la Fuente ◽

Jordi Vilà-Guerau de Arellano ◽

Ana Prieto ◽

...

Keyword(s):

Large Scale ◽

Spatial Scales ◽

Open Water ◽

Water Evaporation ◽

Distributed Temperature Sensing ◽

Field Campaign ◽

Spatial And Temporal Scales ◽

Airborne Measurements ◽

Dry Air ◽

Evaporation Dynamics

In the endorheic basins of the Altiplano, water is crucial for sustaining unique ecological habitats. Here, the wetlands act as highly localized evaporative environments, and little is known about the processes that control evaporation. Understanding evaporation in the Altiplano is challenging because these environments are immersed in a complex topography surrounded by desert and are affected by atmospheric circulations at various spatial scales. Also, these environments may be subject to evaporation enhancement events as the result of dry air advection. To better characterize evaporation processes in the Altiplano, the novel Evaporation caused by Dry Air Transport over the Atacama Desert (E-DATA) field campaign was designed and tested at the Salar del Huasco, Chile. The E-DATA combines surface and airborne measurements to understand the evaporation dynamics over heterogeneous surfaces, with the main emphasis on the open water evaporation. The weather and research forecasting model was used for planning the instruments installation strategy to understand how large-scale air flow affects evaporation. Instrumentation deployed included: meteorological stations, eddy covariance systems, scintillometers, radiosondes and an unmanned aerial vehicle, and fiber-optic distributed temperature sensing. Additional water quality and CO2 fluxes measurements were carried out to identify the link between meteorological conditions and the biochemical dynamics of Salar del Huasco. Our first results show that, in the study site, evaporation is driven by processes occurring at multiple spatial and temporal scales and that, even in the case of available water and energy, evaporation is triggered by mechanical turbulence induced by wind.

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Habitat selection of Marbled Teal and White-headed Duck during the breeding and wintering seasons in south-eastern Spain

Bird Conservation International ◽

10.1017/s0959270912000305 ◽

2012 ◽

Vol 23 (3) ◽

pp. 344-359 ◽

Cited By ~ 9

Author(s):

ESTHER SEBASTIÁN-GONZÁLEZ ◽

CRISTINA FUENTES ◽

MARCOS FERRÁNDEZ ◽

JOSÉ L. ECHEVARRÍAS ◽

ANDY J. GREEN

Keyword(s):

Habitat Selection ◽

Spatial Scales ◽

Management Strategies ◽

Open Water ◽

Spatial Diversity ◽

Suitable Habitat ◽

Brood Rearing ◽

South Eastern ◽

Natural Park ◽

Selection Of

SummaryUnderstanding habitat requirements is vital for developing successful management strategies for threatened species. In this study we analyse the habitat selection of two globally threatened waterbirds (Marbled Teal Marmaronetta angustirostris and White-headed Duck Oxyura leucocephala) coexisting in an internationally important wetland (El Hondo Natural Park, south-eastern Spain) at three spatial scales. We surveyed adults and broods of these species fortnightly during two consecutive years and we related density and presence of birds to several habitat variables. At a pond-selection scale, the density of both species was related to the surface area of the ponds, with Marbled Teal showing avoidance of medium-sized ponds, and White-headed Ducks strong selection for the largest ponds. Within ponds, Marbled Teal avoided open waters, and was mainly associated with Phragmites reedbeds, but also selected areas with saltmarsh and Scirpus vegetation, especially for brood-rearing. White-headed Duck made more use of deeper areas with open water, especially in winter, and Phragmites was the only emergent vegetation with which it associated. When breeding success was very high in 2000, strong creching of broods was observed in White-headed Duck, but not in Marbled Teal. In order to provide suitable habitat for both species, there is a need to maintain spatial diversity with a combination of large wetlands suitable for both species and small, vegetated ones suitable for the Marbled Teal.

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Variation at range margins across multiple spatial scales: environmental temperature, population genetics and metabolomic phenotype

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2008.1767 ◽

2009 ◽

Vol 276 (1661) ◽

pp. 1495-1506 ◽

Cited By ~ 43

Author(s):

William E Kunin ◽

Philippine Vergeer ◽

Tanaka Kenta ◽

Matthew P Davey ◽

Terry Burke ◽

...

Keyword(s):

Spatial Scales ◽

Physical Distance ◽

Population Variation ◽

Regional Patterns ◽

Range Margin ◽

Arabidopsis Lyrata ◽

Perennial Plant ◽

Temperature Regimes ◽

Population Structures ◽

Genetic Profiles

Range margins are spatially complex, with environmental, genetic and phenotypic variations occurring across a range of spatial scales. We examine variation in temperature, genes and metabolomic profiles within and between populations of the subalpine perennial plant Arabidopsis lyrata ssp. petraea from across its northwest European range. Our surveys cover a gradient of fragmentation from largely continuous populations in Iceland, through more fragmented Scandinavian populations, to increasingly widely scattered populations at the range margin in Scotland, Wales and Ireland. Temperature regimes vary substantially within some populations, but within-population variation represents a larger fraction of genetic and especially metabolomic variances. Both physical distance and temperature differences between sites are found to be associated with genetic profiles, but not metabolomic profiles, and no relationship was found between genetic and metabolomic population structures in any region. Genetic similarity between plants within populations is the highest in the fragmented populations at the range margin, but differentiation across space is the highest there as well, suggesting that regional patterns of genetic diversity may be scale dependent.

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Trypanosoma brucei s.1.: evolution, linkage and the clonality debate

Parasitology ◽

10.1017/s0031182000076940 ◽

1996 ◽

Vol 112 (5) ◽

pp. 481-488 ◽

Cited By ~ 20

Author(s):

J. R. Stevens ◽

M. Tibayrenc

Keyword(s):

Linkage Disequilibrium ◽

Cryptic Species ◽

Trypanosoma Brucei ◽

Temporal Stability ◽

Current Debate ◽

Parasitic Protozoa ◽

Mode Of Reproduction ◽

Population Structures ◽

Two Populations ◽

General Method

SUMMARYThe Index of Association (IA) has been proposed by Maynard Smith et al. (1993) as a general method for characterizing the population structures of microorganisms as either: clonal, epidemic, cryptic species or panmictic. With reference to the current debate surrounding the mode of reproduction in parasitic protozoa, this study explores (i) the suitability and limitations of the IA for characterizing populations of Trypanosoma brucei s.l., and (ii) the idea that the significance of genetic differences between populations may be better understood if the evolution, spread and temporal stability of certain parasite genotypes are also considered. Four populations of T. brucei from Côte d'Ivoire, Uganda and Zambia are analysed using the IA and a complementary test for linkage disequilibrium, test f of Tibayrenc, Kjellberg & Ayala (1990). The two populations from Uganda are characterized as epidemic, while the others appear more or less clonal; the merits of the two methods are compared. The implications of the various population classifications are discussed with reference to genotype longevity in each region; the evolutionary and biomedical consequences of the genetic non-homogeneity of T. brucei are reviewed.

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Assessing Habitat Suitability for the Common Pochard, Aythya Ferina (Anseriformes, Anatidae) at different Spatial Scales in Orel’ River Valley, Ukraine

Ekológia (Bratislava) ◽

10.2478/eko-2021-0018 ◽

2021 ◽

Vol 40 (2) ◽

pp. 154-162

Author(s):

Olexander Ponomarenko ◽

Myhaylo Banik ◽

Olexander Zhukov

Keyword(s):

Habitat Suitability ◽

Ecological Niche ◽

Spatial Scales ◽

Open Water ◽

Google Earth ◽

Coastal Vegetation ◽

Conservation Priorities ◽

The Common ◽

Landscape Level ◽

Common Pochard

Abstract The habitat suitability for the Common Pochard, a duck species in decline, was studied in the middle reaches of the Orel’ River, Central Ukraine, in 2015–2017. The ducks were counted on their breeding grounds with the use of the ground survey technique. The positions of individual birds were estimated by GPS and plotted on the Google Earth map. The Ecological Niche Factor Analysis (ENFA) was applied to assess the habitat suitability. Sentinel-2 image was used to extract 13 ecogeographical variables and to get two measures of the ecological niche (marginality and specialization). The ENFA procedure was applied twice at landscape and sub-landscape levels to describe the habitat selection across sequential spatial scales. Both the axes of marginality and specialization of the ecological niche of the species proved to be significantly different from the random alternatives. At landscape level, the distribution may be predicted with the use of Aerosol/Coastal, Vegetation and Hydrothermal Composite indices (marginality) and Modified Normalized Difference Water (MNDW) Index along with several vegetation indices (specialization). At sub-landscape level, MNDW played a crucial role. The importance of MNDW is mediated by the preference for the wetlands with the stretches of open water which are used by the ducks to initiate flight safely and to optimize diving possibilities. The ENFA is a reliable tool for the assessment of the habitat suitability and for setting the conservation priorities for the Common Pochard.

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Contrasting population structures of three Pristis sawfishes with different patterns of habitat use

Marine and Freshwater Research ◽

10.1071/mf15427 ◽

2017 ◽

Vol 68 (3) ◽

pp. 452 ◽

Cited By ~ 11

Author(s):

N. M. Phillips ◽

J. A. Chaplin ◽

S. C. Peverell ◽

D. L. Morgan

Keyword(s):

Population Structure ◽

Gene Flow ◽

Habitat Use ◽

Microsatellite Loci ◽

Spatial Scales ◽

Marine Waters ◽

Male And Female ◽

Entire Life ◽

Population Structures ◽

Using Data

This research demonstrates how population structure differs in elasmobranchs with different patterns of habitat use. Population structure was assessed using data at microsatellite loci in three species of Pristis sawfishes in northern Australian waters. Statistically significant population structure was found in each of P. clavata (FST = 0.021, F′ST = 0.151, P < 0.001) and P. zijsron (FST = 0.026, F′ST = 0.130, P < 0.001), which spend their entire life in marine waters. In contrast, there was no evidence of significant population structure in P. pristis, which uses freshwater rivers as juveniles and marine waters as adults (FST = 0.004, F′ST = 0.029, P = 0.210). When combined with the results of mtDNA analyses from a previous study, the results suggested that dispersal in P. pristis is male-biased, whereas both male and female gene flow are restricted at large spatial scales in each of P. clavata and P. zijsron in Australian waters. The present study has provided the first evidence of sex-biased dispersal in a sawfish.

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Migrating ospreys use thermal uplift over the open sea

Biology Letters ◽

10.1098/rsbl.2018.0687 ◽

2018 ◽

Vol 14 (12) ◽

pp. 20180687 ◽

Cited By ~ 16

Author(s):

Olivier Duriez ◽

Guillaume Peron ◽

David Gremillet ◽

Andrea Sforzi ◽

Flavio Monti

Keyword(s):

Mediterranean Sea ◽

Air Temperature ◽

Surface Waters ◽

Open Water ◽

Sea Surface ◽

Atmospheric Convection ◽

Pandion Haliaetus ◽

Cosmopolitan Distribution ◽

Open Sea ◽

The Difference

Most large raptors on migration avoid crossing the sea because of the lack of atmospheric convection over temperate seas. The osprey Pandion haliaetus is an exception among raptors, since it can fly over several hundred kilometres of open water. We equipped five juvenile ospreys with GPS-Accelerometer–Magnetometer loggers. All birds were able to find and use thermal uplift while crossing the Mediterranean Sea, on average 7.5 times per 100 km, and could reach altitudes of 900 m above the sea surface. Their climb rate was 1.6 times slower than over land, and birds kept flapping most of the time while circling in the thermals, indicating that convections cells were weaker than over land. The frequency of thermal soaring was correlated with the difference between the sea surface and air temperature, indicating that atmospheric convection occurred when surface waters were warmer than the overlaying air. These observations help explain the transoceanic cosmopolitan distribution of osprey, and question the widely held assumption that water bodies represent strict barriers for large raptors.

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The Best of All Worlds: Streptococcus pneumoniae Conjunctivitis through the Lens of Community Ecology and Microbial Biogeography

Microorganisms ◽

10.3390/microorganisms8010046 ◽

2019 ◽

Vol 8 (1) ◽

pp. 46 ◽

Cited By ~ 2

Author(s):

Lawson Ung ◽

Paulo J. M. Bispo ◽

Noelle C. Bryan ◽

Camille Andre ◽

James Chodosh ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Community Ecology ◽

Disease Transmission ◽

Community Dynamics ◽

Spatial Scales ◽

Microbial World ◽

Next Generation Sequencing Technology ◽

Microbial Biogeography ◽

Ecological Principles ◽

Population Structures

The study of the forces which govern the geographical distributions of life is known as biogeography, a subject which has fascinated zoologists, botanists and ecologists for centuries. Advances in our understanding of community ecology and biogeography—supported by rapid improvements in next generation sequencing technology—have now made it possible to identify and explain where and why life exists as it does, including within the microbial world. In this review, we highlight how a unified model of microbial biogeography, one which incorporates the classic ecological principles of selection, diversification, dispersion and ecological drift, can be used to explain community dynamics in the settings of both health and disease. These concepts operate on a multiplicity of temporal and spatial scales, and together form a powerful lens through which to study microbial population structures even at the finest anatomical resolutions. When applied specifically to curious strains of conjunctivitis-causing, nonencapsulated Streptococcus pneumoniae, we show how this conceptual framework can be used to explain the possible evolutionary and disease-causing mechanisms which allowed these lineages to colonize and invade a separate biogeography. An intimate knowledge of this radical bifurcation in phylogeny, still the only known niche subspecialization for S. pneumoniae to date, is critical to understanding the pathogenesis of ocular surface infections, nature of host-pathogen interactions, and developing strategies to curb disease transmission.

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Multiscale analysis reveals restricted gene flow and a linear gradient in heterozygosity for an island population of feral horses

Canadian Journal of Zoology ◽

10.1139/z09-019 ◽

2009 ◽

Vol 87 (4) ◽

pp. 310-316 ◽

Cited By ~ 12

Author(s):

Z. L. Lucas ◽

P. D. McLoughlin ◽

D. W. Coltman ◽

C. Barber

Keyword(s):

Gene Flow ◽

Spatial Scales ◽

Restricted Gene Flow ◽

Island Population ◽

Feral Horses ◽

Linear Gradient ◽

Linear Habitats ◽

Feral Horse ◽

Feral Population ◽

Sand Bar

We studied the genetic (microsatellite) diversity of a feral population of horses ( Equus caballus L., 1758) on Sable Island, Nova Scotia, Canada (1983–2003), at two spatial scales: (1) for the island as a whole and (2) at the level of four equally sized subdivisions along the length of Sable Island, which is a long (42 km) and narrow (1.5 km) vegetated sand bar. At the island scale (n = 264 horses), observed heterozygosity over 10 loci was 0.647 ± 0.035 (mean ± 1 SE), while expected heterozygosity was 0.696 ± 0.029; we observed significant heterozygote deficiency with all loci considered (P < 0.0001). At the subdivision scale, observed heterozygosity ranged from 0.589 to 0.694 in a gradient from west to east. We observed a corresponding gradient in effective number of alleles and allelic richness. Pairwise values of FST were significant for most subdivision pairs, ranging as high as 0.067 from west to east. Western areas showed highest levels of inbreeding (FIS = 0.113) with outbreeding indicated in the east (FIS = –0.008). Our results suggest that for a large mammal that lives in polygynous social groups, like the feral horse, gene flow along linear habitats (corridors) may be restricted (relative to the dispersal capabilities of the species), even over short distances.

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