Hi, I’m Oliver.

Background A colleague asked a seemingly simple question: “How many water samples would we need to reliably detect a difference in eDNA concentration between a daytime baseline and a nighttime spawning event for a migratory fish species that spawns at night?" A seemingly simple question… So, if you’re trying to detect a spawning event using environmental DNA (eDNA), you’d compare daytime baseline concentrations to nighttime concentrations taken during the spawning window.

How to make polished, publication-ready maps in ggplot2, basemaps, and cowplot for insets.

There are plenty of opportunities to submit new (R) plots to Wikipedia. Let’s do it!

Using automated web scraping across 11 Australian e-commerce platforms between 2020 and 2023, we identified 3,822 plant species for sale and categorized them by regulatory, naturalisation, and native status, flagging emerging invasive species risks and the online platforms most in need of monitoring.

We map the countries and ecosystems of origin behind two decades of U.S. wildlife imports, revealing major gaps in global wildlife trade data and highlighting source regions facing the greatest biodiversity pressure from U.S. demand.

Rainbow Lorikeets are a popular Australian pet species that have also established invasive populations outside their native range. We test whether stable isotope analysis can identify recently escaped or released captive lorikeets within wild populations, informing management along different stages of the pet-release invasion pathway.

Millions of animals, plants, and wildlife products are moved across the globe every year, through both legal markets and illegal smuggling. This trade presents serious conservation and biosecurity threats — removing animals from the wild can endanger populations, and moving them elsewhere can spread disease or create new invasive species. My research quantifies the scale and dynamics of the live wildlife trade, from global import data and online marketplaces to smuggling networks and international policy, to identify the species, pathways, and regulatory gaps that pose the greatest conservation and biosecurity risk.

The Internet is a vast source of data on the wildlife trade, spanning e-commerce sites, classifieds, social media, and the dark web. Data collected online can inform conservation, biosecurity, and law enforcement efforts, yet this approach remains underused. I develop methods to collect and analyze this data at scale, including a working guide for using the Internet to quantify wildlife trade, natural language processing tools to automatically classify online listings, and large-scale e-commerce surveys spanning wildlife and invasive plants, to help researchers and regulators monitor trade that would otherwise go undetected.

Invasive species cause ecological and economic damage, and can even endanger human health. Biological invasions unfold in discrete stages, and my research focuses on the earliest of these: transport, introduction, and establishment. I explore the consequences of the wildlife and plant trade as a pathway for new invasive species, asking what makes certain species more common in trade, why some exotic pets are released into the environment over others, and how regulatory gaps let invasive plants and pests slip through. I also develop tools to manage this risk directly, from theoretical models of propagule pressure to environmental DNA methods for early detection of invasive insects and pathogens before they establish.