scholarly journals Comparison of wormlion behavior under man-made and natural shelters: urban wormlions more strongly prefer shaded, fine-sand microhabitats, construct larger pits and respond faster to prey

2019 ◽  
Vol 66 (1) ◽  
pp. 91-98 ◽  
Author(s):  
Yehonatan Samocha ◽  
Inon Scharf

Abstract Urban habitats differ from their natural surroundings in various aspects, such as a higher temperature and a distinct species composition. It is therefore not surprising that animal behavior too differs between these habitat types. We studied the foraging and habitat selection behavior of a pit-building predator, a wormlion, originating from either an urban or a more natural site. Wormlions occur in nature under structures that provide shelter from sunlight and rain, such as caves, and are also common in cities, occurring under artificial shelters. Wormlions construct pit-traps to hunt arthropods, and the pits constructed by urban wormlions were larger than those constructed by wormlions from caves. Urban wormlions responded faster to prey falling into their pit, probably leading to a higher capture success. We suggest that these 2 findings indicate the higher investment of urban wormlions in foraging, resulting from the higher abundance of potential prey in the city. Urban wormlions were choosier regarding their preferred microhabitat. While both fine sand and shaded microhabitats were preferred by wormlions, urban wormlions demonstrated a greater preference for such conditions. We suggest that relocation is more likely to lead wormlions in cities to find microhabitats of a higher quality compared with wormlions inhabiting caves. This is probably due to the larger areas in the city available for wormlions. Wormlions from the caves possessed more lipids, suggesting that they employ a conservative growth strategy, intended to contend with the uncertainty of prey arrival, in contrast to the city, where potential prey are more abundant.

2011 ◽  
Vol 9 (4) ◽  
pp. 689-695 ◽  
Author(s):  
Sandro Secutti ◽  
Roberto E Reis ◽  
Eleonora Trajano

Two cave populations of Aspidoras albater catfish with reduced eyes and pigmentation were recently found near the city of Posse, São Domingos karst area, Goiás State, representing the first known case of a troglomorphic callichthyid catfish. Cave specimens are described and compared to epigean specimens of A. albater, but morphometric differences between the epigean and the cave populations are not adequate to delimit as distinct species.


2019 ◽  
Vol 14 (2) ◽  
pp. 60-73
Author(s):  
O. I. Galeznik ◽  
A. N. Galkin

The deposits of the Kharkov suite of Paleogene of Belarus are the soils formed at the turn of existence and regression of the last sea basin and the final establishment of the continental situation in the territory of the country. They are widely spread in the south of the republic and lie mostly at depths of 100–110 m. In the southeast of Belarus, along the valleys of large rivers, these soils often reach the surface. The latter predetermined their active use as the foundations of structures. This is especially pronounced in the city of Gomel, where a wide development of territories is currently underway, within which these soils lie at depths of less than 10 m. The purpose of the work is to characterize the conditions for the distribution of the soils of the Kharkov suite of Paleogene within the southeast of Belarus and to study the characteristics of their composition and structure. The work is based on the results of the author's field and laboratory studies, which included a description of the outcrops, pits, and well cores; soil sampling; determination of their chemical and mineral, granulometric and microaggregate compositions, moisture characteristics for the classification of clay soils, as well as the results of statistical data processing. The paper presents the typification of the soil strata of the Kharkov suite of Paleogene of the southeast of Belarus, which allowed us to isolate three characteristic sites that differ in terms of their distribution, depth, thickness of the strata and composition of the soils. Nine granulometric sand and clay differences within the isolated areas were identified. The study of chemical-mineral and granulometric compositions of soils made it possible to identify their significant changes, both in area and in the section, which is caused by confinement to various facies zones, frequent migration of the coastline, long and uneven erosion and glacier-exaction destruction. The interrelation of the mineral composition, size and morphology of sandy soil particles is analyzed, it is noted that in all their varieties medium and fine sand fractions differ in the greatest mineral diversity.


Evolution ◽  
1994 ◽  
Vol 48 (4) ◽  
pp. 1324 ◽  
Author(s):  
Mathew A. Leibold ◽  
Alan J. Tessier ◽  
Colin T. West

The Condor ◽  
2001 ◽  
Vol 103 (4) ◽  
pp. 776-784 ◽  
Author(s):  
Catherine Graham

Abstract Landscape-level behavioral information is needed to understand factors that underlie animal distributions in disturbed habitats. I examined habitat use and activity budgets of Keel-billed Toucans (Ramphastos sulfuratus) in a pasture-dominated landscape in Los Tuxtlas, Mexico. The objectives were to compare habitat selection at two scales, and to describe activity budgets of toucans with an emphasis on how behavior varied by habitat type. Six toucans were followed between January and July 1998 for a total of 349 hr. I noted behavior, bird location, and habitat type. At one spatial scale, birds' individual movement area was a nonrandom portion of the overall study area. When time spent in habitats by individual toucans was compared to habitat available in individual movement areas, habitat selection was also nonrandom. Forest remnants were preferred at both scales. Toucans spent approximately equal time foraging and perching (35–40%). Calling, preening, and social interactions each occupied 10% or less of the birds' activity budgets. All activities occurred in similar proportions in all habitat types, suggesting that different habitats provide many of the same resources. Combining individual patterns of habitat selection with activity budgets yields a better understanding of factors that allow populations to persist in disturbed landscapes. Selección de Hábitat y Asignación de Actividades del Tucán Ramphastos sulfuratus a Escala de Paisaje Resumen. Se requieren estudios de comportamiento enfocados a la escala de paisaje para comprender los factores que afectan la distribución de los organismos en hábitats perturbados. Se examinó el uso de hábitat y asignación de actividades del tucán Ramphastos sulfuratus en paisajes dominados por pastizales en Los Tuxtlas, México. Los objetivos fueron comparar la selección de hábitat a dos escalas espaciales y describir la asignación de actividades de los tucanes poniendo énfasis en cómo el comportamiento es afectado por el tipo de hábitat. Seis tucanes fueron seguidos entre enero y julio de 1998 por un total de 349 hr. Registré el comportamiento, la posición del ave, y el tipo de hábitat. A una de las escalas espaciales consideradas, el area individual de movimiento de las aves representó una porción no azarosa del area total de estudio. Cuando el tiempo consumido por individuo en un hábitat determinado fue comparado con el hábitat disponible en las áreas individuales de movimiento, la selección de hábitat difirió de una selección al azar. Los remanentes de selva fueron preferidos a ambas escalas. Los tucanes consumieron aproximadamente el mismo tiempo forrajeando y posados (35–40%). Los llamadas, así como las interacciones sociales ocuparon 10% o menos de la asignación de actividades de las aves. Todas las actividades se llevaron a cabo en proporciones similares en todos los tipos de hábitat. La combinación de patrones individuales de selección de hábitat con la asignación de actividades proporciona una mejor comprensión de los factores que permiten la subsistencia de poblaciones en hábitats perturbados.


1999 ◽  
Vol 77 (8) ◽  
pp. 1175-1184 ◽  
Author(s):  
W James Rettie ◽  
Philip D McLoughlin

For many species, determination of habitat selection is based on habitat-use data obtained through radiotelemetry. Recent papers pertaining to study techniques have largely ignored the effect of habitat-dependent bias in the performance of radiotelemetry systems. Such biases cannot be overcome by increasing radiotelemetry precision, excluding data, or increasing sample sizes, as the biases are centred around data that are missing or that contain habitat-dependent errors in location. The problem is best addressed at the data-analysis stage through the use of geographic information systems. We used Monte Carlo simulations to assess the effect of habitat-dependent bias in radiotelemetry studies on the assessment of habitat selection. We looked at the effects of habitat-patch size, level of telemetry signal inhibition, level of habitat co-occurrence, and selection pattern. We demonstrated that regarding use as the composition of habitat types within a circular area around each telemetry location can help to overcome the inaccurate assessment of habitat-selection patterns that biased data produce. The size of the circular area best able to overcome the bias is related to habitat patch size and to the level of association between two or more habitat types. Furthermore, we argue that the characteristics of habitat mosaics selected by animals can and should be studied in this way.


Urban Studies ◽  
2009 ◽  
Vol 46 (5-6) ◽  
pp. 1137-1155 ◽  
Author(s):  
Antònia Casellas ◽  
Montserrat Pallares-Barbera

This article investigates the urban and economic revitalisation of a traditional industrial working-class neighbourhood into a knowledge-based economic district. It explores why and how this new district is the result of an assertive public policy led by Barcelona's city council and implemented by a quasi-public agency. The project represents the most important urban-growth strategy in the city at the turn of the century and also exemplifies the advantages and shortcomings of many of the policy elements that have contributed to the radical transformation of Barcelona in recent decades. The article further highlights methodological challenges regarding the conceptualisation and operationalisation of new economic activities and it discusses the spatial and uncertain economic consequences of this ambitious approach by the local government.


Author(s):  
E. N. Mysnik

As a part of the ecological approach, weeds are considered as plants of secondary habitats of natural and artificial origin with disturbed natural vegetation cover. Such habitats are also available in the territory of settlements. Therefore,the study of the specific composition of weeds in the territory of settlements is an important area of scientific research. Thepurpose of this study is to identify the features of the specific composition of weeds depending on the type of habitat in thecity of Vsevolozhsk (Leningrad Region). Аs a result of the study, new data were obtained on the weeds distribution in different types of habitats within the city. For comparison, harvested clogged areas and lawns were selected, 59 and 66 species wereidentified on them, respectively. Species compositions of weeds of comparable habitat types have significant similarities in thetaxonomic structure and composition of species groups which dominate in occurrence (14 common species). The proportion of young (annual and biennial) and perennial species of weeds on the compared types of habitats varies slightly. Together,15 species from the compositions of the dominant species groups are dominant in the fields of the Leningrad Region, whichdemonstrates the relationship between the different components of the weed flora of the Leningrad Region. As a part of the ecological approach, weeds are considered as plants of secondary habitats of natural and artificial origin with disturbed natural vegetation cover. Such habitats are also available in the territory of settlements. Therefore,the study of the specific composition of weeds in the territory of settlements is an important area of scientific research. Thepurpose of this study is to identify the features of the specific composition of weeds depending on the type of habitat in thecity of Vsevolozhsk (Leningrad Region). Аs a result of the study, new data were obtained on the weeds distribution in different types of habitats within the city. For comparison, harvested clogged areas and lawns were selected, 59 and 66 species wereidentified on them, respectively. Species compositions of weeds of comparable habitat types have significant similarities in thetaxonomic structure and composition of species groups which dominate in occurrence (14 common species). The proportion of young (annual and biennial) and perennial species of weeds on the compared types of habitats varies slightly. Together,15 species from the compositions of the dominant species groups are dominant in the fields of the Leningrad Region, whichdemonstrates the relationship between the different components of the weed flora of the Leningrad Region.


2014 ◽  
Vol 1 (4) ◽  
pp. 1-171 ◽  
Author(s):  
Danijela Stešević ◽  
Danka Caković ◽  
Slobodan Jovanović

The paper presents a taxonomic, ecological and phytogeographical study of the native and alien flora of the urban area of Podgorica (Capital of Montenegro, SE Europe). The surveyed terrain extends over 86 km2, and apart from the urban it also entails the peri-urban zone. The checklist of vascular plants of the urban area includes1222 species and subspecies from 561 genera and 121 families which represents a little over a third of the total flora of Montenegro. The richness and diversity of the city’s flora are caused by the local geomorphology and climatic conditions of the area, the high diversity of habitats with different anthropogenic impact and the increased immigration of plants from the surrounding ecosystems. Concerning the distribution of the species number by quadrant in  the city area of Podgorica ther is no gradient between growing number of species and distance from the urban core. However, if the distribution of the number of taxa per habitat is taken into consideration, it is clear that the homogeneity of habitats and the increase in the urbanisation leads to decline of the number of wild growing taxa. The families represented by the highest number of taxa are Poaceae (11.5%), Asteraceae (11.2%) and Fabaceae (9.2%). while the genera represented most are Trifolium (2.1%), Euphorbia (1.4%), Carex, Ranunculus and Bromus (1.3 each%), Veronica (1.2%), Allium (1.1%), Vicia and Lathyrus (1% each). Apart from the expected high presence of synanthropic, ruderal and ruderal-segetal taxa, the flora of Podgorica is characterised by a significant number of typical urbanophobes. Comparing to the flora of selected European cities (Zurich, Vienna, Rome, Patras and Thessaloniki), Podgorica showed the biggest similarity with Rome (Sørensen’s quotient of similarity (Q/S)= 69.4). The general life form spectrum  has therophytic-hemicryptophytic character, which, on one hand, reflects the climatic conditions and on the other the intensive urbanisation of the surveyed area. Like in the spectrum of other Mediterranean cities, the participation of the geophytes is relatively high (11.7%). Conserning phenology, Podgorica is a city in which no interruption of vegetation growth and something is always in flower. The majority of plants flower in May, the smallest number flowers in December. Regarding the ecological temperature index, dominating in the city area are thermophilic plants (T7 and T8), an indication of the Mediterranean character of the city area. Prevalent in terms of the light index are heliophyllic plants (L7 and L8), conditioned by exposure of the terrain to sunlight, as well as by the degradation of the primary forest cover and the domination of open and sunny habitats. Dominant in terms of soil reaction are neutrophilic and neutro-basophilic species (R5 and R7), and in terms of nutrients oligotrophic plants (N2 and N3). Dominating in terms of the humidity index are H3 and H4 plants, as expected considering the climatic conditions and hydrography of the area. The phytogeographic spectrum of Podgorica fits into the general spectrum of South European cities and is characterised by the prevailing presence of Mediterranean species s.l. (39.7%). The participation of aliens is relatively small (14.1%), probably due to the short history of the settlement and the poorly developed transportation and trading networks. Dominant among aliens are taxa of Asteraceae (15.7%) and plants of Asian (43%) and North American origin (23.2%). The most aggressive aliens in the city area are Ailanthus altissima, Artemisia annua, A. verlotiorum, Bidens subalternans, Broussonetia papyrifera, taxa of the genus Erigeron, Symphyotrichum squamatum and Xanthium orientale subsp. italicum.The comparative analysis of selected habitat types in the area of Podgorica showed that two habitat types are distinguished by prominent floristic richness: meadows (46.1%) and dikes along railroad tracks (32.1%). Due to constant degradation and loss of habitat in the strict urban zone of Podgorica which on one hand causes the loss of native flora, and on the other facilitates the expansion of the alien flora, we expect the effect of the biotic homogenisation to be noticeable in the area of Podgorica.The allergenic flora of Podgorica includes 253 taxa of wild vascular plants whose pollen has been grouped into three categories: woody plants pollen (32 taxa), weed pollen (76 taxa) and grass pollen (145). Tree pollen is present from February to April, while weed and grass pollen from April to October.


2009 ◽  
Vol 4 (2) ◽  
pp. 33-39 ◽  
Author(s):  
Emiliano Esterci Ramalho ◽  
William Ernest Magnusson

Understanding how a species moves between habitats available in its home range is key for interpreting spatial-temporal habitat selection patterns, foraging behavior, and predator-prey interactions. The use of habitat by the jaguar(Panthera onca) generally reflects the density and movement of its prey and not the availability of habitats. However, there is no information about how the species uses the habitats available in the Amazonian várzea. The objective of this study was to test if the jaguar uses the habitats available in the surroundings of várzea lakes, in proportion to their availability or if it shows preference for a specific habitat type. To achieve this objective we surveyed, on foot, the surroundings of 36 várzea lakes in the Mamirauá Sustainable Development Reserve, recording jaguar presence through observation of signs and identifying and quantifying the available habitats. Although we found signs of jaguar presence in all habitat types surveyed, the number of signs found in habitat type chavascal was greater than expected by its availability...


Biologia ◽  
2021 ◽  
Author(s):  
Jing Wang ◽  
Shengnan Ji ◽  
Jiayi Wu ◽  
Tej Kumar Shrestha ◽  
Xiangli Bu ◽  
...  

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