A reanalysis of apparent survival rates of Indiana myotis (Myotis sodalis)

AbstractTo estimate annual apparent local survival, we collected capture–resighting data on 256 individually marked male Western Sandpipers (Calidris mauri) wintering at Estero de Punta Banda, Mexico, between 1994–1997. A hierarchical modeling approach was used to address the effect of age class and year on survivorship rates. The best-fit model included a constant apparent survival probability (ϕ = 0.489; 95% CI = 0.410–0.569), but several models fit nearly as well, and averaging among the top five, to account for model uncertainty, suggested that adults had somewhat higher values than juveniles (ϕ = 0.490 ± 0.051 vs. 0.450 ± 0.067). Detection probability was substantially higher for adults than for juveniles (p = 0.741 vs. p = 0.537). Those apparent survival estimates are low compared with those from other studies of Western Sandpipers at breeding and other nonbreeding locations, and substantially lower than the true survivorship rates expected for small sandpipers in general. We interpret these results as indicating that this site is of below average quality for nonbreeding male Western Sandpipers.

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Experts correctly describe demography associated with historical decline of the endangered Indiana bat, but not recent period of stationarity

10.7287/peerj.preprints.2790v1 ◽

2017 ◽

Author(s):

Wayne Thogmartin ◽

Carol Sanders-Reed ◽

Jennifer Szymanski ◽

Lori Pruitt ◽

Michael Runge

Keyword(s):

Population Decline ◽

Survival Rates ◽

Clear Understanding ◽

Myotis Sodalis ◽

Indiana Bat ◽

White Nose Syndrome ◽

Demographic Behavior ◽

Pup Survival ◽

Survival And Reproduction ◽

Reproductive Rates

Demographic characteristics of bats are often insufficiently described for modeling populations. In data poor situations, experts are often relied upon for characterizing ecological systems. In concert with the development of a matrix model describing Indiana bat (Myotis sodalis) demography, we elicited estimates for parameterizing this model from 12 experts. We conducted this elicitation in two stages, requesting expert values for 12 demographic rates. These rates were adult and juvenile seasonal (winter, summer, fall) survival rates, pup survival in fall, and propensity and success at breeding. Experts were most in agreement about adult fall survival (3% Coefficient of Variation) and least in agreement about propensity of juveniles to breed (37% CV). The experts showed greater concordance for adult ( mean CV, adult = 6.2%) than for juvenile parameters ( mean CV, juvenile = 16.4%), and slightly more agreement for survival (mean CV, survival = 9.8%) compared to reproductive rates ( mean CV, reproduction = 15.1%). However, survival and reproduction were negatively and positively biased, respectively, relative to a stationary dynamic. Despite the species exhibiting near stationary dynamics for two decades prior to the onset of a potential extinction-causing agent, white-nose syndrome, expert estimates indicated a population decline of -11% per year (95% CI = -2%, -20%); quasi-extinction was predicted within a century ( mean = 61 years to QE, range = 32, 97) by 10 of the 12 experts. Were we to use these expert estimates in our modeling efforts, we would have errantly trained our models to a rapidly declining demography asymptomatic of recent demographic behavior. While experts are sometimes the only source of information, a clear understanding of the temporal and spatial context of the information being elicited is necessary to guard against wayward predictions.

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Long-Term Study of Apparent Survival in Pacific Golden-Plovers at a Wintering Ground on Oahu, Hawaiian Islands

The Auk ◽

10.1093/auk/118.2.342 ◽

2001 ◽

Vol 118 (2) ◽

pp. 342-351 ◽

Cited By ~ 1

Author(s):

Oscar W. Johnson ◽

Phillip L. Bruner ◽

Jay J. Rotella ◽

Patricia M. Johnson ◽

Andrea E. Bruner

Keyword(s):

Survival Rates ◽

Winter Mortality ◽

Apparent Survival ◽

Open Population ◽

Long Term Study ◽

Minimum Age ◽

Parsimonious Model ◽

Territorial Status ◽

Breeding Seasons ◽

Wintering Ground

Abstract We monitored the apparent survival of territorial and nonterritorial Pacific Golden-Plovers (Pluvialis fulva) for 20 consecutive nonbreeding seasons at a wintering ground within Bellows Air Force Station (BAFS) on the eastern shore of Oahu, Hawaii. Territorial birds were especially site-faithful from season to season, and each surviving individual reoccupied the same territory held in previous seasons. On average, territorial birds were resighted for about twice as many postbanding seasons (4.2) as nonterritorial birds (1.8). Open-population modeling indicated that apparent survival varied by age and territorial status. Our most parsimonious model estimated apparent annual survival rates in territorial plovers as 0.90 for young birds (age determined from retained juvenal primaries) from their first through their second wintering season, and 0.80 for adults over numerous seasons. For nonterritorial plovers, the corresponding values were 0.82 and 0.67, respectively. Despite lower apparent survival in nonterritorial plovers, it remains uncertain whether nonterritoriality actually results in shorter life spans. Some surviving nonterritorial birds may have gone undetected (detection probability of 0.70) because of permanent emigration from the study area. Given strong site-fidelity of territorial birds and the relative certainty of detecting them (probability = 1.0), we regarded the disappearance of a plover from its territory as an indicator of mortality. From last-recorded sightings, we concluded that territorial birds died with about equal frequency during the nonbreeding and breeding seasons. Because the latter is of much shorter duration, time-relative hazards were greatest while birds were away from the wintering grounds. Winter mortality was caused by accidents (collisions with overhead wires and other obstructions), and probable predation by owls. We estimated mean additional life expectancy among territorial plovers at 5.1 years for first-year birds, and 4.5 years for unknown-age adults. The oldest known-age individual was a male that lived 13 years 10 months; in adults of uncertain ages, one male survived to a minimum age of 18 years 10 months, and two females to at least 17 years 10 months. Pacific Golden-Plovers wintering at BAFS, especially territorial birds, demonstrated relatively high rates of apparent survival combined with adaptability for coexistence with humans in an urban environment.

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Use of Bat Boxes by a Maternity Colony of Indiana Myotis (Myotis sodalis)

Northeastern Naturalist ◽

10.1656/1092-6194(2005)012[0217:uobbba]2.0.co;2 ◽

2005 ◽

Vol 12 (2) ◽

pp. 217-220 ◽

Cited By ~ 15

Author(s):

Christopher M. Ritzi ◽

Brianne L. Everson ◽

John O. Whitaker

Keyword(s):

Myotis Sodalis ◽

Myotis Myotis

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Juvenile survival and recruitment in a population of Weddell seals (Leptonychotes weddellii) in McMurdo Sound, Antarctica

Canadian Journal of Zoology ◽

10.1139/z87-453 ◽

1987 ◽

Vol 65 (12) ◽

pp. 2993-2997 ◽

Cited By ~ 15

Author(s):

J. Ward Testa

Keyword(s):

Census Data ◽

Survival Rates ◽

Breeding Population ◽

Weddell Seal ◽

Adult Survival ◽

Juvenile Survival ◽

Apparent Survival ◽

Mcmurdo Sound ◽

Juvenile Dispersal ◽

Weddell Seals

Survival and recruitment of Weddell seal pups were studied in eastern McMurdo Sound, Antarctica. Pups were marked and their apparent survival estimated by mark–recapture methods. The resulting estimates were used together with published estimates of adult survival, yearly sighting probabilities, and direct counts of pup production to simulate the dynamics of the population and evaluate the assumption that it is closed to immigration. Estimates derived from census data in 1982 and 1983 were over five times larger than those simulated. This discrepancy was due to the extremely low juvenile survival rates calculated from marked seals. Since few animals born in Erebus Bay return to breed, the large adult breeding population must be the result of substantial immigration, indicating an important role for juvenile dispersal in the population dynamics of Weddell seals.

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AGE-SPECIFIC VARIATION IN APPARENT SURVIVAL RATES OF MALE LESSER PRAIRIE-CHICKENS

The Condor ◽

10.1650/7502 ◽

2005 ◽

Vol 107 (1) ◽

pp. 78 ◽

Cited By ~ 20

Author(s):

Christian A. Hagen ◽

James C. Pitman ◽

Brett K. Sandercock ◽

Robert J. Robel ◽

Roger D. Applegate

Keyword(s):

Survival Rates ◽

Apparent Survival ◽

Specific Variation

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Apparent Survival Rates of Western Sandpiper (Calidris mauri) Wintering in Northwest Baja California, Mexico

The Auk ◽

10.2307/4090139 ◽

2003 ◽

Vol 120 (1) ◽

pp. 55-61

Author(s):

Horacio de la Cueva ◽

Nils Warnock ◽

David B. Lank

Keyword(s):

Baja California ◽

Survival Rates ◽

Apparent Survival ◽

Calidris Mauri ◽

Western Sandpiper

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What do we know about survival of Common cranes? An elementary introduction with Euring databank

10.1101/2021.09.02.458691 ◽

2021 ◽

Author(s):

Luis M. Bautista ◽

Juan C. Alonso

Keyword(s):

Population Dynamics ◽

Western Europe ◽

Great Increase ◽

Survival Rates ◽

Apparent Survival ◽

Elapsed Time ◽

In Captivity ◽

Species Population ◽

Grus Grus ◽

Common Crane

The increase of the western populations of Common cranes (Grus grus) in the last five decades highlights the need to estimate survival rates. According to Euring databank (EDB), the oldest Common crane ever known was 27 years old in year 2017. This lifespan was obtained by means of 24,900 recoveries of 2,124 ringed cranes collected between years 1936 and 2017. Nearly all cranes were ringed and observed in the last 30 years, and therefore the elapsed time was not enough to reach the maximum longevity reported for the species in captivity (43 years, Mitchell 1911). Life expectancy was five years on average after the ring was attached. Here we provide some elementary analyses to calculate the annual apparent survival rate (ϕ = 0.85) and the annual encounter probability (p = 0.45) of Common cranes, as a first step to advance in the knowledge of the species' population dynamics. The great increase of breeding and wintering crane populations in western Europe in the last decades remains largely unexplained.

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Age-specific survival in an English Twite population.

10.1101/2021.11.24.469575 ◽

2021 ◽

Author(s):

Ismini Gkourtsouli-Antoniadou ◽

Steven R. Ewing ◽

George Hudson ◽

Michael A. Pearson ◽

Julia Schroeder ◽

...

Keyword(s):

Habitat Degradation ◽

Survival Rates ◽

Bird Species ◽

Small Population ◽

Juvenile Survival ◽

Apparent Survival ◽

Mark Recapture ◽

The Uk ◽

Rule Out

Like many bird species associated with agricultural habitats in the UK, the Twite Linaria flavirostris has undergone severe declines over recent decades due to habitat degradation, with populations in England, Wales and Ireland now restricted to a few small pockets. However, the demographic drivers of these declines are still largely unresolved. We estimated the survival of Twite from a small population at the southernmost edge of the English range in Derbyshire using capture-mark-recapture data from 2016–2019. Annual apparent survival for juveniles (0.14–0.34) was lower than for adults (0.29–0.56) and less than that of other Cardueline finches. Our results suggest that low juvenile survival may be one demographic driver underpinning the recent decline of the Derbyshire Twite population, although we also cannot rule out the possibility that differences in emigration of juveniles and adults from the population also contribute to the observed age-specific apparent survival rates.

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Experts correctly describe demography associated with historical decline of the endangered Indiana bat, but not recent period of stationarity

10.7287/peerj.preprints.2790 ◽

2017 ◽

Author(s):

Wayne Thogmartin ◽

Carol Sanders-Reed ◽

Jennifer Szymanski ◽

Lori Pruitt ◽

Michael Runge

Keyword(s):

Population Decline ◽

Survival Rates ◽

Clear Understanding ◽

Myotis Sodalis ◽

Indiana Bat ◽

White Nose Syndrome ◽

Demographic Behavior ◽

Pup Survival ◽

Survival And Reproduction ◽

Reproductive Rates

Demographic characteristics of bats are often insufficiently described for modeling populations. In data poor situations, experts are often relied upon for characterizing ecological systems. In concert with the development of a matrix model describing Indiana bat (Myotis sodalis) demography, we elicited estimates for parameterizing this model from 12 experts. We conducted this elicitation in two stages, requesting expert values for 12 demographic rates. These rates were adult and juvenile seasonal (winter, summer, fall) survival rates, pup survival in fall, and propensity and success at breeding. Experts were most in agreement about adult fall survival (3% Coefficient of Variation) and least in agreement about propensity of juveniles to breed (37% CV). The experts showed greater concordance for adult ( mean CV, adult = 6.2%) than for juvenile parameters ( mean CV, juvenile = 16.4%), and slightly more agreement for survival (mean CV, survival = 9.8%) compared to reproductive rates ( mean CV, reproduction = 15.1%). However, survival and reproduction were negatively and positively biased, respectively, relative to a stationary dynamic. Despite the species exhibiting near stationary dynamics for two decades prior to the onset of a potential extinction-causing agent, white-nose syndrome, expert estimates indicated a population decline of -11% per year (95% CI = -2%, -20%); quasi-extinction was predicted within a century ( mean = 61 years to QE, range = 32, 97) by 10 of the 12 experts. Were we to use these expert estimates in our modeling efforts, we would have errantly trained our models to a rapidly declining demography asymptomatic of recent demographic behavior. While experts are sometimes the only source of information, a clear understanding of the temporal and spatial context of the information being elicited is necessary to guard against wayward predictions.

Download Full-text