Efficient single-survey estimation of carnivore density using fecal DNA and spatial capture-recapture: a bobcat case study

Abstract This article presents original mixed method research to describe the use of rare illicit psychoactive substances, with special emphasis on crack cocaine in France. We first introduce a unique monitoring system committed to the observation of hard-to-reach populations. Qualitative findings rely, among others, on perennial ethnographic studies and field professionals’ knowledge to provide guidance to estimate the number of crack cocaine users. We then rely on a set of multilevel capture-recapture estimators, a statistical procedure to indirectly estimate the size of elusive populations. Since prior field evidence suggests an increasing diversity in crack cocaine users’ profiles, we provide a measure of heterogeneity to assess which estimator better fits the data. The calculated estimates are then critically reviewed and debated in light of the previously gathered information. Our results uncover both individual and institutional heterogeneity and suggest that the spread of crack cocaine in France initiated earlier than originally thought. Our case study underlines the need for field-driven assessments to put quantitative results into perspective, a necessary step to tailor efficient health policy responses.

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Simulation-based validation of spatial capture-recapture models: A case study using mountain lions

PLoS ONE ◽

10.1371/journal.pone.0215458 ◽

2019 ◽

Vol 14 (4) ◽

pp. e0215458 ◽

Cited By ~ 2

Author(s):

J. Terrill Paterson ◽

Kelly Proffitt ◽

Ben Jimenez ◽

Jay Rotella ◽

Robert Garrott

Keyword(s):

Mountain Lions ◽

Simulation Based ◽

Capture Recapture

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Monitoring browsing behaviour and search services evolution adaptation with a capture–recapture Internet-based programming technique: A case-study over medical portals

Information Services & Use ◽

10.3233/isu-2007-27304 ◽

2007 ◽

Vol 27 (3) ◽

pp. 105-122

Author(s):

Ioannis Anagnostopoulos ◽

Ilias Maglogiannis

Keyword(s):

Programming Technique ◽

Capture Recapture

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Does a suburban reserve host a significant Carabuspopulations? A capture-recapture case study in Budapest, Hungary

ARPHA Conference Abstracts ◽

10.3897/aca.2.e46305 ◽

2019 ◽

Vol 2 ◽

Author(s):

Bérces Sándor

Keyword(s):

Survival Rate ◽

Population Size ◽

Total Population ◽

Pitfall Traps ◽

Forested Area ◽

Habitat Islands ◽

Capture Recapture ◽

To Receive

A two season capture-recapture study was preformed between 2016-2017, focusing on the Carabus species living in a suburban park (3 hectare) in Budapest, Hungary. Eighty live-capture, non-baited pitfall traps were used in a 3 x 3 m grid in 4 rows and 20 columns, covering almost totally a forested area of 240 m2. Five Carabus species were captured, the most numerous were C. scheidleri, C. ullrichii and C. coriaceus. C. convexus and C. intricatus were captured only a few times. All Carabus species were individually marked and released. Population size and survival rate was estimated only for the C. scheidleri population using POPAN in order to receive gross population size. In total 491 C. scheidleri individuals (251 females and 239 males) were marked. Recapture rate in 2016 and 2017 were 41 and 50 percent for the total population respectively. Estimated population size varied between years, the maximum population size was 680 ± 50 specimen in 2016. In 2017 a population size of 190 ± 16 individuals were estimated. Overwintering of eight C. scheidleri and three C. ullrichii specimen were observed. Less mobile large bodied forest specialist Carabus species living in a relatively small reserve underline the importance of habitat islands in a city.

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