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A Real-Time Interactive System for Studying Confrontational Pursuit Behavior in Rodents

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Swift declines predicted following mating system changes driven by an introduced predator.

Timothy F Wright¹

¹Biology Department, New Mexico State University, Las Cruces, New Mexico.

The Journal of Animal Ecology

|April 9, 2019

Summary

This summary is machine-generated.

Changes in adult sex ratios can significantly impact endangered species. Male-biased ratios in swift parrots led to shared paternity, reduced nesting success, and predicted population declines.

Keywords:

adult sex ratio invasive predator mating system parrot polyandry population fitness

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Predicting the Effectiveness of Population Replacement Strategy Using Mathematical Modeling

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Published on: July 3, 2007

Area of Science:

Ecology
Conservation Biology
Animal Behavior

Background:

Adult sex ratio variation is understudied compared to offspring sex ratio.
Critically endangered species face unique conservation challenges.
Predation can significantly alter adult sex ratios in wild populations.

Purpose of the Study:

To investigate the impact of adult sex ratio bias on mating systems, reproductive success, and population viability.
To examine how predation affects the adult sex ratio and subsequent breeding dynamics in the swift parrot (Lathamus discolor).
To model the long-term consequences of altered mating systems on population persistence.

Main Methods:

Combined demographic data with genetic analyses to assess mating patterns.
Quantified nesting success and fledging rates at sites with varying predation levels.
Developed population viability models incorporating observed rates of mixed paternity.

Main Results:

Male-biased adult sex ratios were observed at sites with high sugar glider predation.
Females in these areas exhibited increased rates of mating with multiple males (shared paternity).
Higher levels of mixed paternity correlated with reduced nesting success and fewer fledged chicks.
Population viability models predicted substantial population declines, particularly under high mixed paternity scenarios.

Conclusions:

Adult sex ratio bias has profound effects on mating systems and reproductive output.
Shared paternity, driven by male-biased adult sex ratios, negatively impacts individual fitness and population viability.
Conservation strategies for endangered species must consider the influence of adult sex ratios and associated mating system shifts.