Date of Award

Fall 11-21-2025

Document Type

Honors Thesis

Department/Major

Biology

First Advisor

Jeff Wesner

Second Advisor

Jake Kerby

Third Advisor

Mark Dixon

Keywords

Insect decline, insect population, insect apocalypse, NEON, aquatic macroinvertebrate

Subject Categories

Biodiversity | Biology | Life Sciences

Abstract

There is a common idea that there is an “insect apocalypse”, that insect populations are on a drastic decline. To test this hypothesis we took data collected by the National Ecological Observatory Network (NEON) from 2015 to 2023 and analyzed it to create a time series model depicting the population of aquatic macroinvertebrates at 34 sites across North America (Appendix 1). NEON is an NSF funded, continental-scale observation facility designed to collect long-term open-access ecological data to better understand the complexities of Earth's ecosystems and how they are changing. From this model, we defined the slope of the change in population over time to determine whether there was a significant pattern of decline in aquatic macroinvertebrate populations. Of the 34 sites, about half fell into the decreasing category with the other half into the increasing category. Nearly all of the sites had slopes between -0.49 and 0.27, indicating an average change in insect density (no/m2) between about -68% and about 86% per year. Average yearly change of insect density lies between about 28% decrease and 35% increase (95% CI). This alludes to there not being a massive insect decline crisis across North America, instead insect population change appears to be idiosyncratic. This contradicts the common idea of an insect apocalypse, which provides some hope for the future of many ecosystems.

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