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Using Pharmacological Manipulation and High-precision Radio Telemetry to Study the Spatial Cognition in Free-ranging Animals

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Amur Softshell Turtle (Pelodiscus maackii) Population Size, Structure, and Spatial Distribution.

Xiaochen Hou¹, Haitao Shi²

¹School of Life Science, Tonghua Normal University, Tonghua 134001, China.

Animals : an Open Access Journal From MDPI

|January 25, 2025

Summary

This summary is machine-generated.

Conservation of Amur softshell turtles (ASTs) in Northeast China is crucial. This study estimated AST population density and identified key habitats, providing vital data for effective conservation strategies.

Keywords:

amur softshell turtle closed population conservation continuous-time capture–recapture method population size

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Area of Science:

Ecology
Conservation Biology
Herpetology

Background:

Freshwater turtle preservation requires understanding population dynamics and distribution.
Amur softshell turtles (ASTs) in Northeast China face steep population declines due to low awareness and protection.
Urgent conservation efforts are needed for this vulnerable species.

Purpose of the Study:

To investigate the population density and structure of Amur softshell turtles (ASTs) in the Ussuri River's Jewellery Island area.
To utilize continuous-time capture-recapture methods for estimating AST population size in a closed population.
To analyze the influence of environmental variables on AST distribution within the study area.

Main Methods:

A three-month mark-recapture study was conducted in 2022.
Capture-recapture data from 35 juvenile captures (12 recaptures from 23 marked individuals) were analyzed.
Surveyed sites were divided into seven sections based on natural characteristics to assess environmental influences.

Main Results:

The estimated AST population size was 40.79 ± 9.75 individuals (0.663 ± 0.158 turtles/ha).
Approximately 35.4-85.2% of the estimated population was marked during the study.
AST distribution varied significantly among sections, with 91% of captures occurring at vegetated shorelines and in water channel 2.

Conclusions:

This study provides essential baseline data for AST population assessment and conservation.
The findings highlight the importance of vegetated shorelines and specific water channels for ASTs.
Informed conservation strategies are necessary to address the decline of Amur softshell turtles.