Population size, survivorship, density, and capture probability ofChelydra serpentinainhabiting an urban environment

2014 ◽  
Vol 59 (3) ◽  
pp. 331-336 ◽  
Author(s):  
Francis L. Rose ◽  
Michael F. Small
Keyword(s):  
Population Size ◽  
Urban Environment ◽  
Capture Probability

scholarly journals Urban Sloths: Public Knowledge, Opinions and Interactions

2018 ◽  
Author(s):  
Kissia Ferreira Pereira ◽  
Robert John Young ◽  
Vanner Boere ◽  
Ita de Oliveira e Silva
Keyword(s):  
Population Size ◽  
Urban Environment ◽  
Negative Impact ◽  
Biological Knowledge ◽  
Public Knowledge ◽  
Public Square ◽  
Human Interactions ◽  
Human Animal ◽  
Animal Interaction ◽  
Bradypus Variegatus

Free-range sloths living in an urban environment is rare. In this study, human opinions, attitudes and interactions with a population of Bradypus variegatus in a public square were investigated. A questionnaire was applied to people in the square where the sloths reside, and informal, opportunistic observations of human-sloth interactions were made. 95% of respondents knew of the sloths’ existence in the square and 87.8% likes their presence. Opinions about population size differed greatly and younger people were concerned if the square was appropriate place for them. Some human-sloth interactions showed the consequence of lack of biological knowledge. People initiated all sloth-human interactions. The fact that sloths are strictly folivorous has limited their interactions with humans and consequently minimised negative impact of the human-animal interaction on their wellbeing. These results demonstrate that while there is a harmonious relationship between people and sloths, actions in environmental education of the square’s public could be beneficial for the sloths.

scholarly journals Urban Optimum Population Size and Development Pattern Based on Ecological Footprint Model: Case of Zhoushan, China

2016 ◽  
Vol 3 (3) ◽  
Author(s):  
Yuan LU
Keyword(s):  
Population Size ◽  
Urban Environment ◽  
Ecological Footprint ◽  
Natural Capital ◽  
Development Pattern ◽  
Optimum Population ◽  
Footprint Model ◽  
Ecological Resources ◽  
Optimal Population ◽  
The City

The agglomeration of population in the city can reflect the prosperity in the economy, society and culture. However, it has also brought a series of problems like environmental pollution, traffic congestion, housing shortage and jobs crisis. The results can be shown as the failure of urban comprehensive function, the decline of city benefits, and the contradiction between socioeconomic circumstance and ecosystem. Therefore, a reasonable population capacity, which is influenced by ecological resources, urban environment, geographical elements, social and economic factors, etc., is objectively needed. How to deal with the relationship between the utilization of natural capital and development of the city is extremely essential. This paper takes Zhoushan Island as an example, which is the fourth largest island off the coast of China. Firstly, the interactively influencing factors of urban optimal population are illustrated. And method is chosen to study the optimal population size. Secondly, based on the model of ecological footprint (EP), the paper calculates and analyzes the ecological footprint and ecological capacity of the Zhoushan Island, in order to explore the optimal population size of the city. Thirdly, analysis and evaluation of the resources and urban environment carrying capacity is made. Finally, the solution of the existing population problems and the suggestion for the future development pattern of the city are proposed in the urban eco-planning of Zhoushan Island. The main strategies can be summarized in two aspects: one is to reduce the ecological footprint, the other is to increase the ecological supply. The conclusion is that the current population of Zhoushan Island is far beyond the optimum population size calculated by the ecological footprint model. Therefore, sustainable development should be the guidance for urban planning in Zhoushan Island, and a low-carbon development pattern for the city is advocated.

Estimates of sex ratio require the incorporation of unequal catchability between sexes

2012 ◽  
Vol 39 (4) ◽  
pp. 350 ◽  
Author(s):  
Evan J. Pickett ◽  
Michelle P. Stockwell ◽  
Carla J. Pollard ◽  
James I. Garnham ◽  
John Clulow ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Population Size ◽  
Population Studies ◽  
Capture Probability ◽  
Ecological Studies ◽  
Mark Recapture ◽  
Closed Population ◽  
Litoria Aurea ◽  
Biased Sex Ratio ◽  
Probability Methods

Context Estimates of the sex ratio of a population are a common summary statistic used for ecological studies and conservation planning. However, methods to determine the sex ratio often ignore capture probability, which can lead to a perceived bias in the sex ratio when the sexes are detected at different rates. Aims To illustrate the bias from conventional count-based analysis methods for determining sex ratio by comparison with analytical methods that include capture probability. Methods Closed-population mark–recapture analysis was used to determine the population size of each sex within a population of green and golden bell frogs (Litoria aurea). This was then compared with the traditional count-based methods of estimating sex ratio to determine the effect of incorporating capture probability on the sex ratio estimate. Key results More males than females were detected during surveys, producing a male-biased sex ratio when there was no incorporation of capture probability. Mark–recapture results indicated a similar population size between the two sexes, suggesting that the sex ratio is closer to even. Conclusions Methods to estimate sex ratio that incorporate capture probability can significantly reduce the bias obtained from count data. Implications We suggest that population studies must incorporate capture probability to determine the sex ratio of a population.

scholarly journals Estimation of Population Size When Capture Probability Depends on Individual States

2018 ◽  
Vol 24 (1) ◽  
pp. 154-172 ◽  
Author(s):  
Hannah Worthington ◽  
Rachel S. McCrea ◽  
Ruth King ◽  
Richard A. Griffiths
Keyword(s):  
Population Size ◽  
Capture Probability

scholarly journals A Thermodynamic Analysis of Urbanization

2005 ◽  
Vol 4 (1) ◽  
pp. 78-84
Author(s):  
T. Srivenkataramana ◽  
T. Balakrishna Bhat
Keyword(s):  
Population Size ◽  
Urban Environment ◽  
Thermodynamic Analysis ◽  
Rural Population ◽  
Dynamic Equilibrium ◽  
High Density ◽  
The World ◽  
Process Of Urbanization

This article deals with application of concepts in thermodynamics to the process of urbanization which is a global phenomenon. The disorder in urban environment due to high density of population is likened to the entropy concept of thermodynamics which is assumed to increase with population size. This introduces a check on urbanization and leads to a dynamic equilibrium between urban and rural population components. A discussion is provided on a few factors which may be monitored to control urbanization particularly in the less developed regions of the world.

scholarly journals Movements and capture-recapture data analysis of the vesper rat (Nyctomys sumichrasti : Rodentia, Muridae) in a tropical forest in northeastern Oaxaca, Mexico.

2010 ◽  
Vol 26 (3) ◽  
Author(s):  
Martín Pérez-Lustre ◽  
Antonio Santos-Moreno
Keyword(s):  
Data Analysis ◽  
Standard Deviation ◽  
Population Size ◽  
Extreme Values ◽  
Average Distance ◽  
Survival Rates ◽  
Capture Probability ◽  
Complete Study ◽  
Capture Recapture ◽  
Males And Females

In order to explain the population demography of the Vesper Rat (Nyctomys sumichrasti) and with regarding to an estimate of population size and survival rates, as well as possible differences in the movements distances between males and females, we analyzed capture-recapture data of this species from a trapping effort of 455 trap-nights and a total of 157 captures of 36 individuals which were livetraped at 3 trap heights: 3-9 m above ground (low canopy), 9-15 m (medium canopy) and the highest part of the canopy, 15-21.5 m. Due to differences between age categories in sample size, the analysis of capture-recapture histories was restricted to adult individuals. The sample of 29 adult individuals included 12 females (8 singletons and 4 captured in the complete study) and 17 males (5 singletons and 12 captured in the complete study); which represents a sex-ratio of 1:1.41, which did not differ statistically from 1:1. The capture-recapture histories were analyzed using the Cormack-Jolly-Seber model, where the best model maintains the survival constant and equal between sexes, and capture probability is constant through time, but differs between sexes. The survival probability was 0.8287, while the capture probability was 0.874 for males and 0.5733 for females. Estimated population size included 19 males and 21 females. The average distance travelled by females was 34.86 m (standard deviation 5.92) with extreme values of 20.1 to 60.32, whereas for males was 35.42 m (standard deviation 18.27), with extreme values of 10.3 to 75.1 m.

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