An open spatial capture–recapture model for estimating density, movement, and population dynamics from line‐transect surveys

The influence of animal mobility on the assumption of uniform distances in aerial line-transect surveys

Wildlife Research ◽

10.1071/wr07077 ◽

2008 ◽

Vol 35 (4) ◽

pp. 275 ◽

Cited By ~ 31

Author(s):

Rachel M. Fewster ◽

Colin Southwell ◽

David L. Borchers ◽

Stephen T. Buckland ◽

Anthony R. Pople

Keyword(s):

Survey Design ◽

Distance Sampling ◽

High Mobility ◽

Line Transect ◽

Transect Line ◽

Aerial Surveys ◽

Pack Ice ◽

Capture Recapture ◽

Distance Data ◽

Crabeater Seals

Line-transect distance sampling is a widely used method for estimating animal density from aerial surveys. Analysis of line-transect distance data usually relies on a requirement that the statistical distribution of distances of animal groups from the transect line is uniform. We show that this requirement is satisfied by the survey design if all other assumptions of distance sampling hold, but it can be violated by consistent survey problems such as responsive movement of the animals towards or away from the observer. We hypothesise that problems with the uniform requirement are unlikely to be encountered for immobile taxa, but might become substantial for species of high mobility. We test evidence for non-uniformity using double-observer distance data from two aerial surveys of five species with a spectrum of mobility capabilities and tendencies. No clear evidence against uniformity was found for crabeater seals or emperor penguins on the pack-ice in East Antarctica, while minor non-uniformity consistent with responsive movement up to 30 m was found for Adelie penguins. Strong evidence of either non-uniformity or a failure of the capture–recapture validating method was found for eastern grey kangaroos and red kangaroos in Queensland.

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Sex‐specific population dynamics of ocelots in Belize using open population spatial capture–recapture

Ecosphere ◽

10.1002/ecs2.2792 ◽

2019 ◽

Vol 10 (7) ◽

Cited By ~ 3

Author(s):

Christopher B. Satter ◽

Ben C. Augustine ◽

Bart J. Harmsen ◽

Rebecca J. Foster ◽

Marcella J. Kelly

Keyword(s):

Population Dynamics ◽

Specific Population ◽

Open Population ◽

Capture Recapture

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Breeding transients in capture–recapture modeling and their consequences for local population dynamics

Scientific Reports ◽

10.1038/s41598-020-72778-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Daniel Oro ◽

Daniel F. Doak

Keyword(s):

Growth Rate ◽

Population Dynamics ◽

Population Growth ◽

Population Growth Rate ◽

Local Population ◽

Environmental Stochasticity ◽

Adult Survival ◽

Local Survival ◽

First Reproduction ◽

Capture Recapture

Abstract Standard procedures for capture–mark–recapture modelling (CMR) for the study of animal demography include running goodness-of-fit tests on a general starting model. A frequent reason for poor model fit is heterogeneity in local survival among individuals captured for the first time and those already captured or seen on previous occasions. This deviation is technically termed a transience effect. In specific cases, simple, uni-state CMR modeling showing transients may allow researchers to assess the role of these transients on population dynamics. Transient individuals nearly always have a lower local survival probability, which may appear for a number of reasons. In most cases, transients arise due to permanent dispersal, higher mortality, or a combination of both. In the case of higher mortality, transients may be symptomatic of a cost of first reproduction. A few studies working at large spatial scales actually show that transients more often correspond to survival costs of first reproduction rather than to permanent dispersal, bolstering the interpretation of transience as a measure of costs of reproduction, since initial detections are often associated with first breeding attempts. Regardless of their cause, the loss of transients from a local population should lower population growth rate. We review almost 1000 papers using CMR modeling and find that almost 40% of studies fitting the searching criteria (N = 115) detected transients. Nevertheless, few researchers have considered the ecological or evolutionary meaning of the transient phenomenon. Only three studies from the reviewed papers considered transients to be a cost of first reproduction. We also analyze a long-term individual monitoring dataset (1988–2012) on a long-lived bird to quantify transients, and we use a life table response experiment (LTRE) to measure the consequences of transients at a population level. As expected, population growth rate decreased when the environment became harsher while the proportion of transients increased. LTRE analysis showed that population growth can be substantially affected by changes in traits that are variable under environmental stochasticity and deterministic perturbations, such as recruitment, fecundity of experienced individuals, and transient probabilities. This occurred even though sensitivities and elasticities of these parameters were much lower than those for adult survival. The proportion of transients also increased with the strength of density-dependence. These results have implications for ecological and evolutionary studies and may stimulate other researchers to explore the ecological processes behind the occurrence of transients in capture–recapture studies. In population models, the inclusion of a specific state for transients may help to make more reliable predictions for endangered and harvested species.

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The influence of spatio-temporal resource fluctuations on insular rat population dynamics

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2011.1121 ◽

2011 ◽

Vol 279 (1729) ◽

pp. 767-774 ◽

Cited By ~ 18

Author(s):

James C. Russell ◽

Lise Ruffino

Keyword(s):

Population Dynamics ◽

Resource Availability ◽

Rattus Rattus ◽

Resource Subsidies ◽

Driven Systems ◽

Resource Pulses ◽

State Capture ◽

Main Driver ◽

Capture Recapture ◽

Spatio Temporal

Local spatio-temporal resource variations can strongly influence the population dynamics of small mammals. This is particularly true on islands which are bottom-up driven systems, lacking higher order predators and with high variability in resource subsidies. The influence of resource fluctuations on animal survival may be mediated by individual movement among habitat patches, but simultaneously analysing survival, resource availability and habitat selection requires sophisticated analytical methods. We use a Bayesian multi-state capture–recapture model to estimate survival and movement probabilities of non-native black rats ( Rattus rattus ) across three habitats seasonally varying in resource availability. We find that survival varies most strongly with temporal rainfall patterns, overwhelming minor spatial variation among habitats. Surprisingly for a generalist forager, movement between habitats was rare, suggesting individuals do not opportunistically respond to spatial resource subsidy variations. Climate is probably the main driver of rodent population dynamics on islands, and even substantial habitat and seasonal spatial subsidies are overwhelmed in magnitude by predictable annual patterns in resource pulses. Marked variation in survival and capture has important implications for the timing of rat control.

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ESTIMATION OF COCCINELLID NUMBERS AND MOVEMENT IN THE FIELD

The Canadian Entomologist ◽

10.4039/ent113981-11 ◽

1981 ◽

Vol 113 (11) ◽

pp. 981-997 ◽

Cited By ~ 27

Author(s):

P. M. Ives

Keyword(s):

Population Dynamics ◽

Population Estimates ◽

Catch Per Unit Effort ◽

Mark Recapture ◽

Aphid Density ◽

Visual Sampling ◽

Individual Marking ◽

Pea Aphids ◽

Capture Recapture ◽

Experimental Plots

AbstractChanges in the numbers of adults of Coccinella californica Mannerheim and C. trifasciata Mulsant in small plots of alfalfa and oats were monitored over the summers of 1974 and 1975 by mark–recapture methods. Aphid population dynamics in the plots were studied concurrently. In the second summer, movements of the beetles were also monitored by means of individual marking and sticky net traps. Approximately 1000 beetles of each species were marked in the first summer; in the second, roughly 5000 and 3000 respectively. The capture–recapture method was tested with a caged population, and was found to be feasible for estimation of the coccinellid numbers. Catch per unit effort, using visual sampling that was not dependent on marking, provided an acceptable index of numbers which could give population estimates when calibrated against mark–recapture estimates.The number of beetles trapped on the sticky nets was primarily a function of numbers in the plots and temperature, with the two species having different relationships between temperature and flight. But for C. californica, the numbers trapped were also a function of aphid density in the plots; the data suggested that for C. trifasciata the same is probably true, but the range of densities of pea aphids was too narrow to show it. In both seasons, C. trifasciata was predominant in the alfalfa and C. californica in the oats. Plot to plot movements by overwintered beetles reflected the same apparent preference. Changes in the numbers of coccinellids in the experimental plots, and their reproductive success, are discussed in the light of these findings.

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ABUNDANCE OF BLUE AND HUMPBACK WHALES IN THE EASTERN NORTH PACIFIC ESTIMATED BY CAPTURE-RECAPTURE AND LINE-TRANSECT METHODS

Marine Mammal Science ◽

10.1111/j.1748-7692.2004.tb01141.x ◽

2004 ◽

Vol 20 (1) ◽

pp. 63-85 ◽

Cited By ~ 101

Author(s):

John Calambokidis ◽

Jay Barlow

Keyword(s):

North Pacific ◽

Humpback Whales ◽

Line Transect ◽

Capture Recapture

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Changes in social cohesion in a long-lived species under a perturbation regime

10.1101/686451 ◽

2019 ◽

Author(s):

M. Genovart ◽

O. Gimenez ◽

A. Bertolero ◽

R. Choquet ◽

D. Oro ◽

...

Keyword(s):

Population Dynamics ◽

Social Cohesion ◽

Group Living ◽

Social Bonding ◽

World Population ◽

List Type ◽

Social Species ◽

The Social ◽

Capture Recapture ◽

A Site

AbstractUnderstanding the behaviour of a population under perturbations is crucial and can help to mitigate the effects of global change. Sociality can influence the dynamics of behavioural processes and plays an important role on populations’ resilience. However little is known about the effects of perturbations on the social cohesion of group-living animals.To explore the strength of social cohesion and its dynamics under perturbations, we studied an ecological system involving a colonial, long-lived species living in a site experiencing a shift to a perturbed regime. This regime, caused by the invasion of predators, led this colony to hold from 70% to only 3% of the total world population in only one decade. Because birds breed aggregated in discrete and annually changing patches within large colonies, we could disentangle whether annual aggregation was random or resulted from social bonding among individuals. Our goals were 1) to uncover if there was any long-term social bonding between individuals and 2) to examine whether the perturbation regime affected social cohesion.We explored social cohesion by means of contingency tables and, within the Social Network Analysis framework, by modeling interdependencies among observations using additive and multiplicative effects (AME) and accounted for missing data. We analysed 25 years of monitoring with an individual capture-recapture database of more than 3,500 individuals.We showed that social bonding occurs over years in this species. We additionally show that social bonding strongly decreased after the perturbation regime. We propose that sociality and individual behavioural heterogeneity have been playing a major role driving dispersal and thus population dynamics over the study period.Perturbations may lead not only to changes in individuals’ behaviours and fitness but also to a change in populations’ social cohesion. The demographic consequences of the breaking down of social bonds are still not well understood, but they can be critical for population dynamics of social species. Further studies considering individual heterogeneity, sociality and different types of perturbations should be carried out to improve our understanding on the resilience of social species.

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Dealing with many correlated covariates in capture-recapture models

10.1101/097006 ◽

2016 ◽

Author(s):

Olivier Gimenez ◽

Christophe Barbraud

Keyword(s):

Principal Component Analysis ◽

Population Dynamics ◽

Statistical Significance ◽

Principal Component ◽

High Dimensionality ◽

Demographic Parameters ◽

Statistical Tools ◽

Capture Recapture ◽

New Variables ◽

Standard Software

SummaryCapture-recapture models for estimating demographic parameters allow covariates to be incorporated to better understand population dynamics. However, high-dimensionality and multicollinearity can hamper estimation and inference. Principal component analysis is incorporated within capture-recapture models and used to reduce the number of predictors into uncorrelated synthetic new variables. Principal components are selected by sequentially assessing their statistical significance. We provide an example on seabird survival to illustrate our approach. Our method requires standard statistical tools, which permits an efficient and easy implementation using standard software.

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