How to Count Bugs: A Method to Estimate the Most Probable Absolute Population Density and Its Statistical Bounds from a Single Trap Catch.

Ksenia S Onufrieva,Alexey V Onufriev

doi:10.3390/insects12100932

Abstract

Simple SummaryThe importance of conservation and pest management programs cannot be overstated as climate change, loss of biodiversity, and biological invasions are on the rise. Such programs often rely on traps for population detection and monitoring, assigning management and conservation tactics, and evaluating treatment efficacies. In this paper, we propose a universal method for any insect trap system to estimate the most probable absolute population density and its statistical bounds from a single trap catch. This approach will help take insect detection and monitoring to a new, rigorously quantitative level.Knowledge of insect population density is crucial for establishing management and conservation tactics and evaluating treatment efficacies. Here, we propose a simple and universal method for estimating the most probable absolute population density and its statistical bounds. The method is based on a novel relationship between experimentally measurable characteristics of insect trap systems and the probability to catch an insect located a given distance away from the trap. The generality of the proposed relationship is tested using 10 distinct trapping datasets collected for insects from 5 different orders and using major trapping methods, i.e., chemical-baited traps and light. For all datasets, the relationship faithfully ( describes the experiment. The proposed approach will take insect detection and monitoring to a new, rigorously quantitative level. It will improve conservation and management, while driv-ing future basic and applied research in population and chemical ecology.

Highlights

Traps are crucial for monitoring insect activity and are widely used in pest detection and management programs [1,2,3,4,5,6] for evaluating biodiversity and planning conservation [7,8,9] and research [10,11,12,13,14] efforts
Was not ideal when applied to Lymantria dispar (L.) (R = 0.5) [46], which led to development of a different, simple, yet mathematically rigorous, method for connecting the actual trap catch with the most probable population density, along with statistical bounds of the absolute population density [46]
6 of for L. dispar, N. sertifer, D. frontalis, D. pseudotsugae, and Erebidae assemblage; for C. pomonella, H. halys, D. suzukii, D. virgifera, and Sphingidae assemblage, Rmax was estimated using the method described by Miller et al [45] and is marked with an *

Summary

Introduction

Traps are crucial for monitoring insect activity and are widely used in pest detection and management programs [1,2,3,4,5,6] for evaluating biodiversity and planning conservation [7,8,9] and research [10,11,12,13,14] efforts. Miller et al [45] pioneered a method of estimating plume reach and absolute population density from catches in pheromone-baited traps [38,45]. We demonstrate the generality of a simple mathematical relationship between catch probability and distance to the trap for several species of insects from various orders and two major trapping methods, i.e., chemical-baited traps and light attraction. We show how key characteristics of the population density are derived from the trapping data and describe a procedure for data collection and analysis

Methods

Results

Conclusion