Measuring Abundance: Methods for the Estimation of Population Size and Species Richness. Data in the Wild Series. By Graham J. G. Upton. Exeter (United Kingdom): Pelagic Publishing. $97.13 (hardcover); $45.33 (paper). x + 226 p.; ill.; index of examples and general index. ISBN: 978-1-78427-232-6 (hc); 978-1-78427-231-9 (pb); 978-1-78427-233-3 (eb). 2020.

2021 ◽  
Vol 96 (3) ◽  
pp. 219-220
Author(s):  
Jo A. Werba
Keyword(s):  
United Kingdom ◽  
Species Richness ◽  
Population Size ◽  
General Index ◽  
In The Wild

scholarly journals Where Are the Best European Road Runners and What Are the Country Variables Related to It?

2021 ◽  
Vol 13 (14) ◽  
pp. 7781
Author(s):  
Mabliny Thuany ◽  
Sara Pereira ◽  
Lee Hill ◽  
Jean Carlos Santos ◽  
Thomas Rosemann ◽  
...  
Keyword(s):  
Logistic Regression ◽  
United Kingdom ◽  
Gross Domestic Product ◽  
Population Size ◽  
Binary Logistic Regression ◽  
Demographic Characteristics ◽  
Domestic Product ◽  
The United Kingdom ◽  
Relevant Role

Background: The environment can play a relevant role in performance in runners. This study aimed to verify the distribution of the best European road runners across the continent, and to investigate variables related to country representatives in the European Senior outdoor top list 2019. Methods: The sample comprised 563 European runners, aged 18–48 years, ranked in the European Senior outdoor top list 2019 for distances of 10–42 km. Country-related variables were gross domestic product (GDP), competition place, population size, and sports investment. The countries were categorized as “top ten countries” or “other countries”. Binary logistic regression was used for analysis. Results: The United Kingdom showed the highest prevalence of runners in the ranking (men—17.6%; women—23.0%), followed by Spain (male ranking—12.1%) and Germany (female ranking—8.6%). For men, sports investment (OR = 1.13; CI95% = 1.03–1.28) and country GDP (OR = 0.96; CI95% = 0.93–0.98) showed an association with the chances of the athlete to reach the Top 10 ranking, while among women, the only variable significantly related was the competition venue (OR = 3.97; CI95% = 1.40–11.23). Conclusion: As in other sports considered “non-expensive”, the economic and demographic characteristics of the place where athletes train can provide advantages in performance.

Assessing the status of a threatened island endemic, Ctenosaura oedirhina, on Roatán, Honduras

2020 ◽  
Vol 47 (2) ◽  
pp. 137
Author(s):  
A. B. C. Goode ◽  
S. A. Pasachnik ◽  
T. L. Maple
Keyword(s):  
Population Size ◽  
Distance Sampling ◽  
Adult Mortality ◽  
Isolated Populations ◽  
Cultural Traditions ◽  
Island Endemic ◽  
Wild Fauna ◽  
The Status ◽  
In The Wild ◽  
Study Sites

Abstract Context Organisms living in small, isolated populations with very restricted ranges are at high risk of extirpation due to various direct and indirect forces than mainland populations. Roatán spiny-tailed iguanas (Ctenosaura oedirhina) are endemic to the 146-km2 island of Roatán, Honduras. Harvesting for consumption, fragmentation of habitat and predation by domestic animals threaten the existence of this lizard. This species is federally protected in Honduras; however, enforcement is rare. These iguanas are also listed as Endangered by the International Union for Conservation of Nature (IUCN) and are on Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). This species is geographically and genetically isolated into small subpopulations that are declining in density. Aims To estimate the population size of Roatán spiny-tailed iguanas (Ctenosaura oedirhina) on the island of Roatán, Honduras. Methods Distance sampling surveys have been used to monitor this species since 2012, and have been used to determine population density at five study sites. Estimates of density at those sites and across the island were used to calculate the population size of this species. Key results The present study elucidates that the high-density populations remaining are declining. The current population size is estimated to be 3759 (95% CI=1406–12616) individuals within the study sites, with 730 additional iguanas potentially outside of the study sites. Conclusions If the current level of decline continues, this species may become extirpated from some locations on Roatán, and go extinct in the wild. Although Honduras does have laws protecting this species and other wildlife, enforcement must be enhanced. Implications Lack of enforced protection for this species allows poaching for consumption to continue, which has been shown to alter its distribution and cause increased adult mortality. Local customs value the consumption of this species, creating a delicate management situation. Recommendations include strategies that mitigate the threat posed by consumption and increase enforcement of the current laws, while acknowledging cultural traditions.

Fish population size, and not density, as the determining factor of parasite infection: a case study

Parasitology ◽  
2004 ◽  
Vol 128 (3) ◽  
pp. 305-313 ◽  
Author(s):  
A. M. BAGGE ◽  
R. POULIN ◽  
E. T. VALTONEN
Keyword(s):  
Species Richness ◽  
Population Density ◽  
Population Size ◽  
Fish Population ◽  
Host Population ◽  
Fish Length ◽  
Total Fish ◽  
Infection Parameters ◽  
The Mean

The diversity and abundance of parasites vary widely among populations of the same host species. These infection parameters are, to some extent, determined by characteristics of the host population or of its habitat. Recent studies have supported predictions derived from epidemiological models regarding the influence of host population density: parasite abundance and parasite species richness are expected to increase with increasing host population density, at least for directly transmitted parasites. Here, we test this prediction using a natural system in which populations of the crucian carp, Carassius carassius (L.), occur alone, with no other fish species, in a series of 9 isolated ponds in Finland. The ectoparasite communities in these fish populations consist of only 4 species of monogeneans (Dactylogyrus formosus, D. wegeneri, D. intermedius and Gyrodactylus carassii); the total and relative abundance of these 4 species varies among ponds, with one or two of the species missing from certain ponds. Across ponds, only one factor, total fish population size, explained a significant portion of the variance in both the mean number of monogenean species per fish and the mean total abundance of monogenean individual per fish. In contrast, fish population density did not influence either monogenean abundance or species richness, and neither did any of the other variables investigated (mean fish length per pond, number of fish examined per pond, distance to the nearest lake, and several water quality measures). In our system, proximity among fish individuals (i.e. host population density) may not be relevant to the proliferation of monogeneans; instead, the overall availability of host individuals in the host population appeared to be the main constraint limiting parasite population growth.

scholarly journals ENERGY, SPECIES RICHNESS, AND HUMAN POPULATION SIZE: CONSERVATION IMPLICATIONS AT A NATIONAL SCALE

2003 ◽  
Vol 13 (5) ◽  
pp. 1233-1241 ◽  
Author(s):  
Steven L. Chown ◽  
Berndt J. van Rensburg ◽  
Kevin J. Gaston ◽  
Ana S. L. Rodrigues ◽  
Albert S. van Jaarsveld
Keyword(s):  
Species Richness ◽  
Population Size ◽  
Human Population ◽  
National Scale ◽  
Conservation Implications

Nest Volume and Distance between Nests Do Not Affect Population Size or Species Richness of the Termitophilous Corotocini Fauna

2021 ◽  
Vol 59 (1) ◽  
Author(s):  
Carlos M. Pires-Silva ◽  
Igor Eloi ◽  
Bruno Zilberman ◽  
Maria A. Bezerra-Gusmão
Keyword(s):  
Species Richness ◽  
Population Size

Estimates of Species Richness and Population Size Based on Signs, Products, and Effects

2021 ◽  
pp. 268-280
Author(s):  
Peter A. Henderson
Keyword(s):  
Species Richness ◽  
Population Size ◽  
Insect Herbivore ◽  
Animal Groups ◽  
Insect Abundance ◽  
Plant Damage ◽  
Population Indices ◽  
The Relationship ◽  
Damage Criteria

Comparative surveys of species richness for some animal groups can be undertaken by surveying signs or products such as footprints, faeces, nests, burrows, or cast skins. Measures of the size of populations based on the magnitude of their products or effects are often referred to as population indices. Methods based on the collection of insect exuviae and frass are described and their efficiency discussed. Vertebrate monitoring based on a variety of signs is described. Methods that use plant damage criteria to assess insect herbivore abundance are presented. Methods to determine the relationship between plant damage and insect abundance are described.

scholarly journals Host Plant Determines the Population Size of an Obligate Symbiont (Buchnera aphidicola) in Aphids

2016 ◽  
Vol 82 (8) ◽  
pp. 2336-2346 ◽  
Author(s):  
Yuan-Chen Zhang ◽  
Wen-Jie Cao ◽  
Le-Rong Zhong ◽  
H. Charles J. Godfray ◽  
Xiang-Dong Liu
Keyword(s):  
Host Plant ◽  
Population Size ◽  
Plant Extracts ◽  
Host Plants ◽  
Aphis Gossypii ◽  
Buchnera Aphidicola ◽  
Content Type ◽  
Two Generations ◽  
Novel Host ◽  
In The Wild

ABSTRACTBuchnera aphidicolais an obligate endosymbiont that provides aphids with several essential nutrients. Though much is known about aphid-Buchnerainteractions, the effect of the host plant onBuchnerapopulation size remains unclear. Here we used quantitative PCR (qPCR) techniques to explore the effects of the host plant onBuchneradensities in the cotton-melon aphid,Aphis gossypii.Buchneratiters were significantly higher in populations that had been reared on cucumber for over 10 years than in populations maintained on cotton for a similar length of time. Aphids collected in the wild from hibiscus and zucchini harbored moreBuchnerasymbionts than those collected from cucumber and cotton. The effect of aphid genotype on the population size ofBuchneradepended on the host plant upon which they fed. When aphids from populations maintained on cucumber or cotton were transferred to novel host plants, host survival andBuchnerapopulation size fluctuated markedly for the first two generations before becoming relatively stable in the third and later generations. Host plant extracts from cucumber, pumpkin, zucchini, and cowpea added to artificial diets led to a significant increase inBuchneratiters in the aphids from the population reared on cotton, while plant extracts from cotton and zucchini led to a decrease inBuchneratiters in the aphids reared on cucumber. Gossypol, a secondary metabolite from cotton, suppressedBuchnerapopulations in populations from both cotton and cucumber, while cucurbitacin from cucurbit plants led to higher densities. Together, the results suggest that host plants influenceBuchnerapopulation processes and that this may provide phenotypic plasticity in host plant use for clonal aphids.

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