Comparing abundance estimates from closed population mark-recapture models of endangered adult Atlantic sturgeon

Sampling designs for effective monitoring programs are often specific to individual systems and management needs. Failure to carefully evaluate sampling designs of monitoring programs can lead to data that are ineffective for informing management objectives. We demonstrated the use of an individual-based model to evaluate closed-population mark–recapture sampling designs for monitoring fish abundance in open systems, using Murray cod (Maccullochella peelii (Mitchell, 1838)) in the Murray–Darling River basin, Australia, as an example. The model used home-range, capture-probability and abundance estimates to evaluate the influence of the size of the sampling area and the number of sampling events on bias and precision of mark–recapture abundance estimates. Simulation results indicated a trade-off between the number of sampling events and the size of the sampling reach such that investigators could employ large sampling areas with relatively few sampling events, or smaller sampling areas with more sampling events to produce acceptably accurate and precise abundance estimates. The current paper presents a framework for evaluating parameter bias resulting from migration when applying closed-population mark–recapture models to open populations and demonstrates the use of simulation approaches for informing efficient and effective monitoring-program design.

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A Preliminary Abundance Estimate of an Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus) Contingent Within an Open Riverine System

Journal of Northwest Atlantic Fishery Science ◽

10.2960/j.v52.m726 ◽

2021 ◽

Vol 52 ◽

pp. 39-47

Author(s):

Austin Flanigan ◽

◽

Noah Perlut ◽

James Sulikowski

Keyword(s):

Acoustic Telemetry ◽

Gulf Of Maine ◽

River Estuary ◽

Credible Interval ◽

Atlantic Sturgeon ◽

Population Declines ◽

Mark Recapture ◽

Abundance Estimate ◽

Abundance Estimates ◽

Acipenser Oxyrinchus

Abundance estimates are essential for fisheries management, but estimating the abundance of open populations with low recapture rates has historically been unreliable. However, by using mark-recapture data modulated with survivability parameters obtained from analysis of acoustic telemetry data, more accurate abundance estimates can be made for species that exhibit these characteristics. One such species is the Atlantic sturgeon, for which abundance estimates were designated a research priority following precipitous population declines throughout the 20th century. We addressed this research need in the Saco River Estuary (SRE), a system where the Atlantic sturgeon has been extensively studied using mark-recapture and acoustic telemetry methods since 2009. These data were analyzed using Bayesian analysis of a Lincoln-Peterson estimator, constrained with parameters from a Cormack-Jolly-Seber model, to provide an initial abundance estimate for the system. The resulting estimate indicated that approximately 3 299 (95% Credible Interval: 1 462–6 828) Atlantic sturgeon utilize the SRE yearly, suggesting that the SRE provides critical foraging habitat to a large contingent of the species within the Gulf of Maine. The present study demonstrated the method utilized herein was effective in generating a reasonable estimate of abundance in an open system where recapture events are rare, and therefore may provide a valuable technique for supplying initial estimates of fish abundance in additional systems that display similar characteristics.

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Biology, Management, and Protection of North American Sturgeon

Biology, Management, and Protection of North American Sturgeon ◽

10.47886/9781888569360.ch8 ◽

2002 ◽

Keyword(s):

New York ◽

South Carolina ◽

Chesapeake Bay ◽

Hudson River ◽

Delaware Bay ◽

Late Nineteenth Century ◽

Atlantic Sturgeon ◽

Preparation Methods ◽

Abundance Estimate ◽

Abundance Estimates

<em>Abstract.</em>—This paper analyzes historical abundances of spawning stocks of Atlantic sturgeon <em>Acipenser oxyrinchus</em> during the late nineteenth century, when peak United States harvest of Atlantic sturgeon occurred (3,200 metric tons in 1888). The advent of preparation methods for caviar, transportation networks that allowed export of caviar to Europe, improvements in fishing technology, and development of a domestic smoked sturgeon market caused rapid emergence of an Atlantic sturgeon industry after the Civil War. The industry originated and was centered in the Delaware Bay, which supported the most abundant population on the U.S. East Coast. Important fisheries also developed in the Chesapeake Bay, the Carolinas, and Georgia. Caviar was the principal marketable product of the fishery and large females were targeted, resulting in fisheries collapse at the turn of the century. No substantial resurgence of Atlantic sturgeon landings has occurred in the twentieth century. A previous analysis of U.S. Fish Commission catch and effort records for the Delaware Bay fishery provided an estimate of 180,000 females prior to 1890. The Delaware Bay abundance estimate was extrapolated to other states by calculating the mean level of each state’s contribution to U.S. yields during the period 1880–1901. This approach led to abundance estimates of 29,000 for the Southern States (North Carolina, South Carolina, Georgia, Florida), 20,000 for the Chesapeake Bay (Maryland, Virginia), 180,000 for the Delaware Bay, and 6,000 for the Hudson River (New York). Although the approaches used to estimate historical biomass and abundance contain untested assumptions and biases, the dominance of the Delaware Bay population in comparison to others is in part confirmed by the industry that developed there. Given the uncertainty in abundance estimates, conservative benchmarks are proposed of 10,000 females each, for systems that previously supported important fisheries.

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Population size of Aegla longirostri Bond-Buckup and Buckup, 1994 (Crustacea, Decapoda, Anomura): comparison of methods with the mark-recapture technique in closed population

Nauplius ◽

10.1590/2358-2936e2018016 ◽

2018 ◽

Vol 26 (0) ◽

Cited By ~ 1

Author(s):

Joele S. Baumart ◽

Gláucia B. Cogo ◽

Fidel E.C. Morales ◽

Sandro Santos

Keyword(s):

Population Size ◽

Comparison Of Methods ◽

Mark Recapture ◽

Closed Population

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The mark–recapture method applied to population estimates of a freshwater crab on an alluvial plain

Marine and Freshwater Research ◽

10.1071/mf12350 ◽

2013 ◽

Vol 64 (4) ◽

pp. 317 ◽

Cited By ~ 3

Author(s):

Débora de Azevedo Carvalho ◽

Pablo Agustín Collins ◽

Cristian Javier De Bonis

Keyword(s):

Hydrological Cycle ◽

Field Studies ◽

Accurate Method ◽

Alluvial Plain ◽

Short Term ◽

Chi Square ◽

Mark Recapture ◽

Closed Population ◽

Short Term Study ◽

Chi Square Test

Mark–recapture methods are a useful population estimation tool, although with many assumptions that cannot always be satisfied for all types of organisms and environments. In the present study, three mark–recapture methods (Petersen, Schnabel and Schumacher–Eschmeyer) were applied in a preliminary trial to estimate the population size of the crab Trichodactylus borellianus and to gain information that would support the use of the methods in the field. The accuracy of these estimates was verified by analysing the percentage of bias, the width of the confidence intervals, and by a chi-square test. The assumptions of equal catchability and closed population were verified, along with assumptions related to the efficiency of marking. The adjusted methodology was applied in a short-term study of a pond on the Paraná floodplain. The results showed that the assumptions were satisfied for both the experimental and field studies. The Schnabel was the most accurate method evaluated in both studies. Although the Schumacher–Eschmeyer method also provided accurate results in the field study, it needed large samples to give reliable estimates. The applicability of these methods depends on the stage of the hydrological cycle. The choice of a short-term research design will ensure that the assumption of a closed population is valid for research of this type on an alluvial plain.

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Erratum: Validation of Abundance Estimates from Mark-Recapture and Removal Techniques for Rainbow Trout Captured by Electrofishing in Small Streams

North American Journal of Fisheries Management ◽

10.1577/m04-081e.1 ◽

2006 ◽

Vol 26 (2) ◽

pp. 502-502 ◽

Cited By ~ 1

Author(s):

Amanda E. Rosenberger ◽

Jason B. Dunham

Keyword(s):

Rainbow Trout ◽

Mark Recapture ◽

Abundance Estimates ◽

Small Streams

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Change-in-ratio density estimator for feral pigs is less biased than closed mark - recapture estimates

Wildlife Research ◽

10.1071/wr08076 ◽

2008 ◽

Vol 35 (7) ◽

pp. 695 ◽

Cited By ~ 19

Author(s):

Laura B. Hanson ◽

James B. Grand ◽

Michael S. Mitchell ◽

D. Buck Jolley ◽

Bill D. Sparklin ◽

...

Keyword(s):

Estimation Method ◽

Density Estimator ◽

Density Estimates ◽

Mark Recapture ◽

Closed Population ◽

Feral Pigs ◽

Open Population ◽

Detection Probabilities ◽

Models Comparison

Closed-population capture–mark–recapture (CMR) methods can produce biased density estimates for species with low or heterogeneous detection probabilities. In an attempt to address such biases, we developed a density-estimation method based on the change in ratio (CIR) of survival between two populations where survival, calculated using an open-population CMR model, is known to differ. We used our method to estimate density for a feral pig (Sus scrofa) population on Fort Benning, Georgia, USA. To assess its validity, we compared it to an estimate of the minimum density of pigs known to be alive and two estimates based on closed-population CMR models. Comparison of the density estimates revealed that the CIR estimator produced a density estimate with low precision that was reasonable with respect to minimum known density. By contrast, density point estimates using the closed-population CMR models were less than the minimum known density, consistent with biases created by low and heterogeneous capture probabilities for species like feral pigs that may occur in low density or are difficult to capture. Our CIR density estimator may be useful for tracking broad-scale, long-term changes in species, such as large cats, for which closed CMR models are unlikely to work.

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Net-avoidance behaviour in platypuses

Australian Mammalogy ◽

10.1071/am12051 ◽

2013 ◽

Vol 35 (2) ◽

pp. 245 ◽

Cited By ~ 7

Author(s):

Josh Griffiths ◽

Tom Kelly ◽

Andrew Weeks

Keyword(s):

Acoustic Telemetry ◽

Direct Evidence ◽

Avoidance Behaviour ◽

Mark Recapture ◽

Abundance Estimates ◽

Ornithorhynchus Anatinus

It has been suggested that platypuses (Ornithorhynchus anatinus) may avoid nets following capture, compromising abundance estimates using mark–recapture models. Here, we present the first direct evidence of net avoidance behaviour by the platypus. Using acoustic telemetry, we record a platypus bypassing several nets following capture. Understanding variation in capture probabilities will lead to better estimation of platypus abundance, which is currently lacking.

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Abundance of East coast Australian humpback whales (Megaptera novaeangliae) in 2005 estimated using multi-point sampling and capture-recapture analysis

J. Cetacean Res. Manage. ◽

10.47536/jcrm.vi.317 ◽

2020 ◽

pp. 253-259

Author(s):

David A. Paton ◽

Lyndon Brooks ◽

Daniel Burns ◽

Trish Franklin ◽

Wally Franklin ◽

...

Keyword(s):

East Coast ◽

Megaptera Novaeangliae ◽

Humpback Whales ◽

Migration Route ◽

Closed Population ◽

Breeding Stock ◽

Abundance Estimate ◽

Abundance Estimates ◽

Capture Recapture ◽

Near Extinction

The humpback whales (Megaptera novaeangliae) that migrate along the east coast of Australia were hunted to near extinction during the lastcentury. This remnant population is part of Breeding Stock E. Previous abundance estimates for the east Australian portion of Breeding Stock Ehave been based mainly on land-based counts. Here we present a capture-recapture abundance estimate for this population using photo-identificationdata. These data were collected at three locations on the migration route (Byron Bay – northern migration, Hervey Bay and Ballina – southernmigration) in order to estimate the population of humpback whales that migrated along the east coast of Australia in 2005. The capture-recapturedata were analysed using a variety of closed population models with a model-averaged estimate of 7,041 (95% CI 4,075–10,008) whales.

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Evaluation of Long-Term Mark-Recapture Data for Estimating Abundance of Juvenile Fall-Run Chinook Salmon on the Stanislaus River from 1996 to 2017

San Francisco Estuary and Watershed Science ◽

10.15447/sfews.2019v17iss1art4 ◽

2019 ◽

Vol 17 (1) ◽

Cited By ~ 1

Author(s):

Tyler Pilger ◽

Matthew Peterson ◽

Dana Lee ◽

Andrea Fuller ◽

Doug Demko

Keyword(s):

Chinook Salmon ◽

Oncorhynchus Tshawytscha ◽

Estimation Method ◽

Central Valley ◽

Mark Recapture ◽

Important Species ◽

Trap Efficiency ◽

Monitoring Programs ◽

Abundance Estimates

Conservation and management of culturally and economically important species rely on monitoring programs to provide accurate and robust estimates of population size. Rotary screw traps (RSTs) are often used to monitor populations of anadromous fish, including fall-run Chinook Salmon (Oncorhynchus tshawytscha) in California’s Central Valley. Abundance estimates from RST data depend on estimating a trap's efficiency via mark-recapture releases. Because efficiency estimates are highly variable and influenced by many factors, abundance estimates can be highly uncertain. An additional complication is the multiple accepted methods for how to apply a limited number of trap efficiency estimates, each from discrete time-periods, to a population’s downstream migration, which can span months. Yet, few studies have evaluated these different methods, particularly with long-term monitoring programs. We used 21 years of mark-recapture data and RST catch of juvenile fall-run Chinook Salmon on the Stanislaus River, California, to investigate factors associated with trap efficiency variability across years and mark-recapture releases. We compared annual abundance estimates across five methods that differed in treatment of trap efficiency (stratified versus modeled) and statistical approach (frequentist versus Bayesian) to assess the variability of estimates across methods, and to evaluate whether method affected trends in estimated abundance. Consistent with short-term studies, we observed negative associations between estimated trap efficiency and river discharge as well as fish size. Abundance estimates were robust across all methods, frequently having overlapping confidence intervals. Abundance trends, for the number of increases and decreases from year to year, did not differ across methods. Estimated juvenile abundances were significantly related to adult escapement counts, and the relationship did not depend on estimation method. Understanding the sources of uncertainty related to abundance estimates is necessary to ensure that high-quality estimates are used in life cycle and stock-recruitment modeling.

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