scholarly journals Demographic consequences of climate variation along an elevational gradient for a montane terrestrial salamander

2017 ◽  
Author(s):  
Nicholas M. Caruso ◽  
Leslie J. Rissler
Keyword(s):  
Survival Rates ◽  
Elevational Gradient ◽  
Vital Rates ◽  
Life History Variation ◽  
Growth And Survival ◽  
Active Season ◽  
Asymptotic Size ◽  
Capture Recapture ◽  
Survival And Growth ◽  
The Relationship

AbstractClimate change represents a significant threat to amphibians, which are already imperiled. However, for many species, the relationship between demographic vital rates (survival and growth) and climate is unknown, which limits predictive models. Here we describe the life history variation ofPlethodon montanususing capture-recapture data over a period of four years, at five sites along an elevational gradient to determine how survival and growth vary with temperature, precipitation, and how these relationships vary with elevation. We used a hierarchical model to estimate asymptotic size and growth rate, and used a spatial Cormack-Jolly-Seber model to estimate probability of capture and survival, as well as dispersal variance. Our results show that during the active season, growth and survival rates are both positively affected by precipitation, while survival was positively affected by temperature at all elevations, the relationship between growth rates and temperature varied along the elevational gradient. Generally at lower elevations, higher temperatures led to a decrease in growth while at higher elevations the opposite was true. During the inactive season we found elevational variation in the relationship between survival and the amount of snow; at low elevations snowfall was low but survival decreased with increasing snowfall while at higher elevations increasing snowfall lead to higher survival. Our results demonstrate that understanding how the environment can affect salamander demography to develop mechanistic models, will require knowledge of the actual environmental conditions experienced by a given population as well as an understanding of the overall differences in climate at a given site.

scholarly journals A demographic approach to understanding the effects of climate on population growth

2019 ◽  
Author(s):  
Nicholas M. Caruso ◽  
Christina L. Staudhammer ◽  
Leslie J. Rissler
Keyword(s):  
Population Growth ◽  
Life History Traits ◽  
Experimental Studies ◽  
Elevational Gradient ◽  
Early Spring ◽  
Vital Rates ◽  
Active Season ◽  
Temperature And Precipitation ◽  
Early Fall ◽  
Survival And Growth

AbstractAmphibian life history traits are affected by temperature and precipitation. Yet, connecting these relationships to population growth, especially for multiple populations within a species, is lacking and precludes our understanding of how amphibians are distributed. Therefore, we constructed Integral Projection Models (IPM) for five populations along an elevational gradient to determine how climate and season affects population growth of a terrestrial salamander Plethodon montanus and the importance of demographic vital rates to population growth under varying climate scenarios. We found that population growth was typically higher at the highest elevation compared to the lower elevations whereas varying inactive season conditions, represented by the late fall, winter and early spring, produced a greater variation in population growth than varying active season conditions (late spring, summer, and early fall). Furthermore, survival and growth was consistently more important, as measured by elasticity, compared to fecundity and large females had the greatest elasticity compared to all other sizes. Our results suggest that changing inactive season conditions, especially those that would affect the survival of large individuals, may have the greatest impact on population growth. Therefore, we recommend experimental studies focused on the inactive season to determine the mechanism by which these conditions can affect survival.

Industrial Research and Firm Size, Survival, and Growth in American Manufacturing, 1921–1946: An Assessment

1983 ◽  
Vol 43 (4) ◽  
pp. 953-980 ◽  
Author(s):  
David C. Mowery
Keyword(s):  
Firm Size ◽  
Small Firms ◽  
Firm Growth ◽  
Industrial Research ◽  
Large Firms ◽  
Research Activity ◽  
Growth And Survival ◽  
Survival And Growth ◽  
The Impact ◽  
The Relationship

The literature on the development of American industrial research suggests that during the twentieth century large firms “dominated” industrial research, and reaped the majority of the benefits from such activity. This paper utilizes new data to analyze both the relationship between firm size and research employment and the impact of research activity on firm growth and survival during 1921–1946. The results suggest that large firms were no more research-intensive than were small firms during the 1921–1946 period. Research activity significantly enhanced the probability of firms' survival among the ranks of the 200 largest manufacturing firms during 1921–1946. Research employment also improved the growth performance of both large and small firms during 1933–1946.

scholarly journals Size-specific apparent survival rate estimates of white sharks using mark–recapture models

2019 ◽  
Vol 76 (11) ◽  
pp. 2027-2034 ◽  
Author(s):  
Paul E. Kanive ◽  
Jay J. Rotella ◽  
Salvador J. Jorgensen ◽  
Taylor K. Chapple ◽  
James E. Hines ◽  
...  
Keyword(s):  
Survival Rate ◽  
Standard Error ◽  
Survival Rates ◽  
Vital Rates ◽  
Apparent Survival ◽  
Carcharodon Carcharias ◽  
Marine Predator ◽  
Sex Assignment ◽  
Capture Recapture ◽  
Potential Challenge

For species that exist at low abundance or are otherwise difficult to study, it is challenging to estimate vital rates such as survival and fecundity and common to assume that survival rates are constant across ages and sexes. Population assessments based on overly simplistic vital rates can lead to erroneous conclusions. We estimated sex- and length-based annual apparent survival rates for white sharks (Carcharodon carcharias). We found evidence that annual apparent survival differed over ontogeny in a system with competitive foraging aggregations, from 0.63 (standard error (SE) = 0.08) for newly recruiting subadults to 0.95 (SE = 0.02) for the largest sharks. Our results reveal a potential challenge to ontogenetic recruitment in a long-lived, highly mobile top marine predator, as survival rates for subadult white sharks may be lower than previously assumed. Alternatively, younger and competitively inferior individuals may be forced to permanently emigrate from primary foraging sites. This study provides new methodology for estimating apparent survival as a function of diverse covariates by capture–recapture study, including when sex assignment is uncertain.

scholarly journals THE RELATIONSHIP BETWEEN SEASON VARIATIONS AND DEPTH LEVEL ON THE GROWTH AND SURVIVAL RATE OF PEARL OYSTER SEEDS (Pinctada maxima) IN KAPONTORI BAY, BUTON ISLAND

2014 ◽  
Vol 6 (1) ◽  
Author(s):  
M S Hamzah
Keyword(s):  
Survival Rate ◽  
Environmental Conditions ◽  
Survival Rates ◽  
Pearl Oyster ◽  
Mass Mortality ◽  
Depth Level ◽  
Growth And Survival ◽  
Pearl Oysters ◽  
The Relationship ◽  
Similar Growth

<p>The pearl oyster (<span style="text-decoration: underline;">P</span>. <span style="text-decoration: underline;">maxima</span>) farming particularly in the Kapontori Bay, Buton Island waters and in other areas had complained for the mass mortality of pearl oysters saplings on the shell width between 3-4 cm. The mass mortality, was allegedly as a result of changing in environmental conditions and triggered by the shift in seasons. This research aimed to determine the effect of seasonal variations in water conditions at different depth levels on growth and survival of seedlings of pearl oysters conducted on March 27, 2007 to February 28, 2008. This research was very useful for pearl oyster farming in an effort to suppress the mass mortality rates based on the appropriate level of depth and seasons. The variance analyses showed that depth levels affected the survival rates of the pearl oyster seeds significantly (P&lt;0.01). Based on honest significantly difference test, it also showed that the percentage number of survival rate was found higher within the depth of 2m (93.33%). Based on the relationship analyses between length and weight of shell body in all depths indicated a similar growth pattern of  minor allometric (b&lt;3). The growth, survival rate, and environmental conditions based on depth levels on pearl oyster saplings were discussed in this paper.</p> <p>Keywords: Seasonal variation, survival rate, growth, pearl shell (<span style="text-decoration: underline;">P</span>. <span style="text-decoration: underline;">maxima</span>), depth level</p>

scholarly journals Size-by-environment interactions: a neglected dimension of species’ responses to environmental variation

2018 ◽  
Author(s):  
Andrew T. Tredennick ◽  
Brittany J. Teller ◽  
Peter B. Adler ◽  
Giles Hooker ◽  
Stephen P. Ellner
Keyword(s):  
Population Dynamics ◽  
Functional Form ◽  
Survival Rates ◽  
Vital Rate ◽  
Vital Rates ◽  
Size Dependent ◽  
Fluctuating Environments ◽  
The Impact ◽  
The Relationship

AbstractIn both plant and animal systems, size can determine whether an individual survives and grows under different environmental conditions. However, it is less clear whether and when size-dependent responses to the environment affect population dynamics. Size-by-environment interactions create pathways for environmental fluctuations to influence population dynamics by allowing for negative covariation between sizes within vital rates (e.g., small and large individuals have negatively covarying survival rates) and/or size-dependent variability in a vital rate (e.g., survival of large individuals varies less than small individuals through time). Whether these phenomena affect population dynamics depends on how they are mediated by elasticities (they must affect the sizes and vital rates that matter) and their projected impacts will depend on model functional form (the impact of reduced variance depends on the relationship between the environment and vital rate). We demonstrate these ideas with an analysis of fifteen species from five semiarid plant communities. We find that size-by-environment interactions are common but do not impact long-term population dynamics. Size-by-environment interactions may yet be important for other species. Our approach can be applied to species in other ecosystems to determine if and how size-by-environment interactions allow them to cope with, or exploit, fluctuating environments.

scholarly journals THE RELATIONSHIP BETWEEN SEASON VARIATIONS AND DEPTH LEVEL ON THE GROWTH AND SURVIVAL RATE OF PEARL OYSTER SEEDS (Pinctada maxima) IN KAPONTORI BAY, BUTON ISLAND

2014 ◽  
Vol 6 (1) ◽  
Author(s):  
M S Hamzah
Keyword(s):  
Survival Rate ◽  
Environmental Conditions ◽  
Survival Rates ◽  
Pearl Oyster ◽  
Mass Mortality ◽  
Depth Level ◽  
Growth And Survival ◽  
Pearl Oysters ◽  
The Relationship ◽  
Similar Growth

The pearl oyster (P. maxima) farming particularly in the Kapontori Bay, Buton Island waters and in other areas had complained for the mass mortality of pearl oysters saplings on the shell width between 3-4 cm. The mass mortality, was allegedly as a result of changing in environmental conditions and triggered by the shift in seasons. This research aimed to determine the effect of seasonal variations in water conditions at different depth levels on growth and survival of seedlings of pearl oysters conducted on March 27, 2007 to February 28, 2008. This research was very useful for pearl oyster farming in an effort to suppress the mass mortality rates based on the appropriate level of depth and seasons. The variance analyses showed that depth levels affected the survival rates of the pearl oyster seeds significantly (P<0.01). Based on honest significantly difference test, it also showed that the percentage number of survival rate was found higher within the depth of 2m (93.33%). Based on the relationship analyses between length and weight of shell body in all depths indicated a similar growth pattern of  minor allometric (b<3). The growth, survival rate, and environmental conditions based on depth levels on pearl oyster saplings were discussed in this paper. Keywords: Seasonal variation, survival rate, growth, pearl shell (P. maxima), depth level

scholarly journals Toxicity of mercury (Hg) on survival and growth rate, hemato- and histopathological parameters ofOreochromis niloticus

2013 ◽  
Vol 11 (1) ◽  
pp. 38 ◽  
Author(s):  
Kukuh Nirmala ◽  
Yuni Puji Hastuti ◽  
Vika Yuniar
Keyword(s):  
Growth Rate ◽  
Oreochromis Niloticus ◽  
White Blood Cells ◽  
Survival Rates ◽  
Aquatic Organisms ◽  
Growth And Survival ◽  
Randomized Design ◽  
Test Fish ◽  
Survival And Growth ◽  
Haemoglobin Content

<p>Heavy metals are serious pollutants of the aquatic environment because of their environmental persistence and ability to be accumulated by aquatic organisms. <em>Oreochromis niloticus </em>exposed to 0, 0.16, 0.5, and 1.0 ppm Hg for 30 days. The aim of this study was to determine the influence of mercury in water on survival rate, growth rates, hematological, and histological parameters of <em>Oreochromis niloticus</em>. This study was conducted from Mei to June 2009. The experimental design was arranged in completely randomized design with four treatments and three replications. Stock density was 8 fish/aquarium with mean initial body weight was 15.70±1.13 g. Growth and survival rates of test fish were decreased with increasing the Hg concentration. Red blood cell (RBC) count, haematocrit content, and haemoglobin content decreased when compared to the control. The number of white blood cells (WBC) increased in mercuric treated fish. The results are statistically significant at p&lt;0.05 level.</p> <p>Keywords:mercury, survival and growth rate, hematology, histopathology, <em>Oreochromis niloticus</em></p>

Community characteristics of forest understory birds along an elevational gradient in the Horn of Africa: A multi-year baseline

The Condor ◽  
2021 ◽  
Author(s):  
Kyle D Kittelberger ◽  
Montague H C Neate-Clegg ◽  
Evan R Buechley ◽  
Çağan Hakkı Şekercioğlu
Keyword(s):  
Species Richness ◽  
Species Turnover ◽  
Survival Rates ◽  
Elevational Gradient ◽  
Forest Understory ◽  
Bird Abundance ◽  
Tropical Mountains ◽  
Demographic Rates ◽  
Understory Birds ◽  
Over Time

Abstract Tropical mountains are global hotspots for birdlife. However, there is a dearth of baseline avifaunal data along elevational gradients, particularly in Africa, limiting our ability to observe and assess changes over time in tropical montane avian communities. In this study, we undertook a multi-year assessment of understory birds along a 1,750 m elevational gradient (1,430–3,186 m) in an Afrotropical moist evergreen montane forest within Ethiopia’s Bale Mountains. Analyzing 6 years of systematic bird-banding data from 5 sites, we describe the patterns of species richness, abundance, community composition, and demographic rates over space and time. We found bimodal patterns in observed and estimated species richness across the elevational gradient (peaking at 1,430 and 2,388 m), although no sites reached asymptotic species richness throughout the study. Species turnover was high across the gradient, though forested sites at mid-elevations resembled each other in species composition. We found significant variation across sites in bird abundance in some of the dietary and habitat guilds. However, we did not find any significant trends in species richness or guild abundances over time. For the majority of analyzed species, capture rates did not change over time and there were no changes in species’ mean elevations. Population growth rates, recruitment rates, and apparent survival rates averaged 1.02, 0.52, and 0.51 respectively, and there were no elevational patterns in demographic rates. This study establishes a multi-year baseline for Afrotropical birds along an elevational gradient in an under-studied international biodiversity hotspot. These data will be critical in assessing the long-term responses of tropical montane birdlife to climate change and habitat degradation.

scholarly journals Protein utilization, growth and survival in essential-fatty-acid-deficient rats

1996 ◽  
Vol 75 (2) ◽  
pp. 237-248 ◽  
Author(s):  
Christiani Jeyakumar Henry ◽  
Amal Ghusain-Choueiri ◽  
Philip R. Payne
Keyword(s):  
Growth Rate ◽  
Dietary Protein ◽  
Essential Fatty Acids ◽  
Coconut Oil ◽  
Deficient Diet ◽  
Protein Utilization ◽  
Growth And Survival ◽  
Retarded Growth ◽  
Pregnancy And Lactation ◽  
The Relationship

AbstractThe relationship between essential fatty acids (EFA) deficiency and the utilization of dietary protein, growth rate and survival of offspring was investigated in rats during development and reproduction. EFA deficiency was induced by feeding a 200 g casein/kg-based diet containing 70 g hydrogenated coconut oil (HCO)/lkg as the only source of fat. The conversion efficiency of dietary protein was assessed as net protein utilization (NPU), using a 10 d comparative carcass technique. Consumption of the deficient diet during the 10 d assay period induced biochemical changes characteristic of mild EFA deficiency in humans (triene:tetraene 0·27 (SD 0·04) compared with 0·026 (SD 0·004) for wn-deficient controls), but there were no significant changes in growth rate or protein utilization. These variables were also unchanged when the deficient diet was fed for an additional 7 d before the assay, although triene: tetraene increased to 0.8 (SD 0·02). Feeding the deficient diet for 63 d before assay produced severe EFA deficiency (triene:tetraene 1.4 (SD 0·3) v. 0·036 (SD 0·005) for controls), a fall in growth rate (25% during assay period), and NPU (31.5 (SD 0·63) v. 39.0 (SD 0·93) for controls). These severely-EFA-deficient animals had a 30% higher fasting-resting rate of energy metabolism than that of age-matched controls. However, there was no change in the rate of endogenous N loss. Voluntary energy consumption was increased in animals fed on deficient diets, either with 200 g protein/kg, or protein free. The reduced efficiency of protein utilization could be entirely accounted for by the restricted amount of energy available for growth and protein deposition. Consumption of an EFA-deficient diet during pregnancy and lactation resulted in high mortality (11% survival rate at weaning compared with 79% for controls) and retarded growth in the preweaning offspring. It is concluded that animals are particularly sensitive to EFA deficiency during reproduction and pre- and post-natal stages of development. However, after weaning only severe EFA deficiency retarded growth, primarily through changes in energy balance.

Sign in / Sign up

Export Citation Format

Share Document