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2021 ◽  
Author(s):  
◽  
Robin Alexander Fordham

<p>An account is given of ecological studies on the Southern Black-backed Gull Larus dominicanus Licht in which attention is directed to the structure and balance of the Wellington population. This population is large; in the 1963-64 season more than 5,600 pairs were breeding in the study area, and the peak non-breeding season population in 1964 exceeded 12,000 birds. Its growth has been closely associated with the increase of the human population, and the present distribution and dispersal of gulls is strongly influenced by the distribution of " artificial" feeding sites such as refuse tips and meatworks. The population is composed of breeding colonies, night roosting flocks and daily communal flocks which are inter-related by the social activities and dispersal of the birds. Thus the population is more or less integrated, rather than simply comprising discrete geographic units. Seasonal fluctuations in size and age composition of communal flocks are discussed. Breeding success varies between colonies. It is affected by mammalian predation in some, and by drowning in others, while the largest colonies are comparatively safe for breeding birds. The rapid growth of the whole population in the last five to 10 years appears to have some influence on nesting density, clutch size, spread of laying and overall breeding success. In recent years production of young has been twice that required to maintain the population which has grown at the rate of not less than 7.2% annually. Mortality of banded gulls inside and outside the colony is described and the influence of several factors on chick mortality examined. The principal factor limiting the population appears to be the food supply in relation to the number of birds. When numbers increase and the food supply diminishes, major regulation of the population is apparently achieved in the colony by predation (but not cannibalism) of young by adults. Dispersal of banded gulls from the Wellington colonies is very restricted.</p>


2021 ◽  
Author(s):  
◽  
Robin Alexander Fordham

<p>An account is given of ecological studies on the Southern Black-backed Gull Larus dominicanus Licht in which attention is directed to the structure and balance of the Wellington population. This population is large; in the 1963-64 season more than 5,600 pairs were breeding in the study area, and the peak non-breeding season population in 1964 exceeded 12,000 birds. Its growth has been closely associated with the increase of the human population, and the present distribution and dispersal of gulls is strongly influenced by the distribution of " artificial" feeding sites such as refuse tips and meatworks. The population is composed of breeding colonies, night roosting flocks and daily communal flocks which are inter-related by the social activities and dispersal of the birds. Thus the population is more or less integrated, rather than simply comprising discrete geographic units. Seasonal fluctuations in size and age composition of communal flocks are discussed. Breeding success varies between colonies. It is affected by mammalian predation in some, and by drowning in others, while the largest colonies are comparatively safe for breeding birds. The rapid growth of the whole population in the last five to 10 years appears to have some influence on nesting density, clutch size, spread of laying and overall breeding success. In recent years production of young has been twice that required to maintain the population which has grown at the rate of not less than 7.2% annually. Mortality of banded gulls inside and outside the colony is described and the influence of several factors on chick mortality examined. The principal factor limiting the population appears to be the food supply in relation to the number of birds. When numbers increase and the food supply diminishes, major regulation of the population is apparently achieved in the colony by predation (but not cannibalism) of young by adults. Dispersal of banded gulls from the Wellington colonies is very restricted.</p>


Zootaxa ◽  
2021 ◽  
Vol 5061 (2) ◽  
pp. 340-352
Author(s):  
MARCOS FIANCO ◽  
OSCAR J. CADENA-CASTAÑEDA ◽  
NEUCIR SZINWELSKI ◽  
LUIZ R. R. FARIA

Three new species of Anaulacomera are described, Anaulacomera (Anaulacomera) mariellae sp. n. and Anaulacomera (Anallomes) arlindoi sp. n., belonging respectively to the Inermis and Lanceolata species group, and Anaulacomera angelinae sp. n., placed as incertae sedis. The individuals were collected at the Iguaçu National Park and adjacent small fragments of Atlantic Forest, in southwestern Paraná state, Brazil. The description was based on external morphology of males. We also present distribution maps for the species of the Inermis and the Lanceolata species groups.  


2021 ◽  
Vol 13 (12) ◽  
pp. 19799-19807
Author(s):  
Vishal Kumar ◽  
Yashpal Sharma ◽  
Siljo Joseph ◽  
Roshnikumar Ngangom ◽  
Sanjeeva Nayaka

The present study reports 14 lichenized and two lichenicolous fungi new to the mycota of Jammu & Kashmir. The lichenized fungi are Buellia aeruginascens (Nyl.) Zahlbr., Caloplaca pachycheila Poelt & Hinter., Cladonia cervicornis ssp. verticillata (Hoffm.) Ahti, Hafellia curatellae (Malme) Marbach, Hafellia subnexa Marbach, Hafellia tetrapla (Nyl.) Pusswald, Leptogium askotense D.D.Awasthi, Nephromopsis laii (A. Thell & Randlane) Saag & A.Thell, Polycauliona phlogina (Ach.) Arup, Frödén & Søchting, Pyxine cognata Stirt., Rinodina conradii Körb., Rinodina intermedia Bagl., Rinodina oxydata (A.Massal.) A.Massal., and Squamulea squamosa (B.deLesd.) Arup, Søchting & Frödén. The lichenicolous fungi include Abrothallus microspermus Tul. and Lichenoconium lecanorae (Jaap) D.Hawksw. The species are enumerated along with their present distribution.


2021 ◽  
Vol 7 (2) ◽  
pp. 327-330
Author(s):  
Amani Remmo ◽  
Norbert Löwa ◽  
Julija Peter ◽  
Frank Wiekhorst

Abstract The unique magnetic properties of magnetic nanoparticles (MNP) combined with their small size already led to numerous medical applications. Accurate determination of their magnetic properties is a key requirement enquired by users, that is impeded by the ever-present distribution of MNP sizes. Field flow fractionation (FFF) techniques may help to overcome these limitations by first separating the particles before characterization. In this study, we demonstrate the use of centrifugal FFF coupled to online detectors for fractionation, structural, and magnetic characterization of MNP. The primary goal is to establish a reproducible centrifugal FFF (CF3) method for MNP fractionation We show that CF3 has the same capability as other FFF techniques in resolving the bimodal hydrodynamic size distribution present in the commercial MNP system Resovist® but is faster and more straightforward through its technical approach.


2021 ◽  
Vol 58 ◽  
pp. 183-197
Author(s):  
Ulf Schiefelbein ◽  
Terkel Arnfred ◽  
Christian Dolnik ◽  
Patrick Neumann ◽  
Emilia Ossowska ◽  
...  

The past and present distribution of Lobaria pulmonaria in Denmark, northern Germany, northwestern Poland and nemoral parts of Skåne, Blekinge, southwesternmost Småland and southern Öland (Sweden) has been studied. Of 124 localities visited between 2015 and 2018, L. pulmonaria was confirmed at 64 sites, at each of which its habitat ecology and viability were investigated. It is almost extinct in Schleswig-Holstein, in southern Jutland, on the Danish Islands, in southwestern Skåne, in Mecklenburg-Vorpommern and in the western part of Pomerania. It has disappeared almost completely from areas where mesophytic forests form the potential natural vegetation. The commonest habitats for L. pulmonaria are species-poor acidic beech and species-poor oak forests, and the commonest substrates are trunks of beech, followed by oak. L. pulmonaria specimens on about two thirds of the colonized trees were in a healthy condition. The situation is worst in Schleswig-Holstein and on the Danish Islands, but best in Blekinge and central and northern Jutland. Recent distribution seems to be influenced by both anthropogenic (e.g. air pollution by sulphur dioxide and nitrogen and forestry practices) and natural factors (precipitation, temperature, air humidity), as well as unnatural climatic factors (global warming).


Diametros ◽  
2021 ◽  
Author(s):  
Massimo Reichlin

Tännsjö’s book Setting Health-Care Priorities defends the view that there are three main normative theories in the domain of distributive justice, and that these theories are both highly plausible in themselves, and practically convergent in their normative conclusions. All three theories (utilitarianism, the maximin/leximin theory and egalitarianism) point to a somewhat radical departure from the present distribution of medical resources: in particular, they suggest redirecting resources from marginal life extension to the care of mentally ill patients. In this paper I wish to argue, firstly, that prioritarianism should not be considered as an amendment to utilitarianism, as it is in Tännsjö’s view, but as a distinctive fourth option. This can best be appreciated if we focus on a reading of the theory that emphasizes its derivation from egalitarianism and its attempt to develop an intermediate approach between utilitarian and egalitarian intuitions. Secondly, in response to Tännsjö’s central objection to prioritarianism, I will argue that the theory does not apply in intrapersonal cases but is only relevant for decisions regarding the interpersonal distribution of benefits. Finally, I will suggest that a practical convergence of the four theories on specific issues such as artificial reproduction or mood enhancement is far less likely than Tännsjö seems to believe.


Author(s):  
Marta Krzyzanska ◽  
Harriet V. Hunt ◽  
Enrico R. Crema ◽  
Martin K. Jones

AbstractWe present a species distribution model (SDM) of Fagopyrum esculentum (buckwheat) in China using present distribution data and estimates for the past based on palaeoclimatic reconstructions. Our model estimates the potential area suitable for buckwheat cultivation over the last 8,000 years, with northeast China consistently showing the highest suitability, providing insights on the discrepancy between the location of the earliest archaeobotanical records in the area and its origins in southwest China based on biogeographic and genetic data. The model suggests little to no variation over time in the spatial extent of the potential area suitable for buckwheat cultivation. In the northern parts of China, the limits of the ecological niche largely fall within the borders of the study area, while to the west it never extends into the main Tibetan plateau, explaining the lack of fossil evidence from Central Asia. In the southwest, the niche overlaps with the borders of modern China, which supports this direction as a viable route of westward dispersal. The comparison between the prediction from the model and sites with archaeobotanical evidence for Fagopyrum indicates that the environmental niche it occupied remained stable over time. This may contrast with a dispersal pattern characterised by continuous adaptations to new environments facilitated by human activity, which may be suggested for other major and minor crops.


Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1454
Author(s):  
Ilenia Clavero-Camacho ◽  
Juan Emilio Palomares-Rius ◽  
Carolina Cantalapiedra-Navarrete ◽  
Guillermo León-Ropero ◽  
Jorge Martín-Barbarroja ◽  
...  

This study delves into the diagnosis of pin nematodes (Paratylenchus spp.) in Spain based on integrative taxonomical approaches using 24 isolates from diverse natural and cultivated environments. Eighteen species were identified using females, males (when available) and juveniles with detailed morphology-morphometry and molecular markers (D2-D3, ITS and COI). Molecular markers were obtained from the same individuals used for morphological and morphometric analyses. The cryptic diversity using an integrative taxonomical approach of the Paratylenchus straeleni-species complex was studied, consisting of an outstanding example of the cryptic diversity within Paratylenchus and including the description of a new species, Paratylenchus parastraeleni sp. nov. Additionally, 17 already known species were identified comprising P. amundseni, P. aciculus, P. baldaccii, P. enigmaticus, P. goodeyi, P. holdemani, P. macrodorus, P. neoamblycephalus, P. pandatus, P. pedrami, P. recisus, P. sheri, P. tateae, P. variabilis, P. veruculatus, P. verus, and P. vitecus. Eight of these species need to be considered as first reports for Spain in this work (viz. P. amundseni, P. aciculus, P. neoamblycephalus, P. pandatus, P. recisus, P. variabilis, P. verus and P. vitecus). Thirty-nine species of Paratylenchus have been reported in Spain from cultivated and natural ecosystems. Although we are aware that nematological efforts on Paratylenchus species in Southern Spain have been higher than that carried out in central and northern part of the country, the present distribution of the genus in Spain, with about 90% of species (35 out of 39 species, and 24 of them confirmed by integrative taxonomy) only reported in Southern Spain, suggest that this part of the country can be considered as a potential hotspot of biodiversity.


2021 ◽  
Vol 21 (1/2) ◽  
pp. 55-62
Author(s):  
A. B. Petrovskiy ◽  
◽  
A. A. Shpagina ◽  
A. A. Kidov ◽  
◽  
...  

The common frog (Rana temporaria) and the moor frog (R. arvalis) lived in all green areas of Moscow until the end of the 20th century. The reduction in the area of woody vegetation, the destruction of breeding sites and introduction of the invasive fish Perccottus glenii contributed to the extinction of these amphibians in most of the city. The paper provides information on the distribution of brown frogs in Moscow based on the results of monitoring in 2020. R. temporaria was found in 37 localities in the Northwestern (6 points), Northern (3 points), Northeastern (1 point), Eastern (9 points), Southeastern (1 point), Southern (5 points), Southwestern (5 points) and Western (7 points) administrative districts. Eleven finds (29.7%) are located outside of specially protected natural areas. Most of the species’ habitats (30 points, or 81.1%) are isolated from other populations. R. arvalis was found in 14 localities in the Northwestern (3 points), Northern (3 points), Eastern (4 points), Southwestern (1 point) and Western (3 points) administrative districts of Moscow. Of all the finds noted, three ones (21.4%) are located outside of specially protected natural areas. The vast majority of the habitats of the species (10 points, or 71.4%) are isolated.


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