Solve the right problems

How should countries think about border biosecurity when even the most stringent system in the world is fallible? By Anna Mouton.

“It’s very tempting to believe that the biosecurity system is like a wall that protects all our valued assets from the pernicious effects of invasive species,” said Prof. Andrew Robinson. “I want to suggest that a wall is a bad mental image.”

Speaking at the 2026 Hortgro Technical Symposium, Robinson, who directs the Centre of Excellence for Biosecurity Risk Analysis (CEBRA), argued for more collaborative, realistic, and scientific mental models of biosecurity.

CEBRA, an initiative of the Australian government, is based at the School of BioSciences at the University of Melbourne. It is co-funded by the University, the Australian Department of Agriculture, Fisheries and Forestry (DAFF), and the New Zealand Ministry for Primary Industries. It performs contract research for the latter two, states and territories, and industry partners.

Biosecurity can be breached

To illustrate the limitations of border biosecurity systems, Robinson described what he considers the world’s best biosecurity system, at Barrow Island off the coast of Western Australia. Barrow Island is a predator-free nature reserve, home to 24 rare species (including the Barrow Island boodie), some of which occur nowhere else.

In 2003, the Chevron Corporation was granted permission to develop a section of Barrow Island as part of the Gorgon natural gas project. Under their agreement with the Australian government, Chevron implemented a rigorous biosecurity system.

Robinson gave examples of the lengths to which Chevron goes to prevent the introduction of exotic species, including vacuuming the clothes and pockets of visitors to the island, shrink-wrapping break-bulk and equipment before shipping, and redesigning the shipping containers and systems.

Nonetheless, Chevron intercepted more than 200 species at the border between 2009 and 2015. Notably, Chevron’s post-border biosecurity surveillance identified around 50 unique species introductions during that period, each requiring eradication.

“This tells us that we can’t rest on our laurels and pretend that a biosecurity system is a wall that protects us,” said Robinson. “We need to involve ourselves in all elements of the system under all circumstances.”

A biosecurity paradigm shift

Robinson highlighted two problems with seeing biosecurity as a wall. “It focuses too much attention on what happens at the border, and not nearly enough on pre- and post-border activities,” he said. “And, when the wall is breached, then the implication is that the game is over, so we all hang up our boots and go home.”

He offered a different paradigm: biosecurity as a hockey game in which all team members are on the field together.

In biosecurity, the forwards are gathering intelligence, monitoring supply chains, and engaging with international bodies and stakeholders. The midfield is the border. The backs are domestic stakeholders, including industries, interest groups, and all levels of government.

And the goalie? “The goalie is everybody!” said Robinson. “Everybody needs to defend the goal of the biosecurity system, because we all benefit from it, and the system needs everybody’s investment to survive.”

Besides the emphasis on pre- and post-border measures and on collaboration, Robinson thinks the hockey analogy has another crucial feature. “When a goal is scored against the team, the game doesn’t stop,” he said. “We tighten our laces, and we keep on fighting.”

Costs and benefits

One obstacle to biosecurity implementation is the difficulty of demonstrating its financial return. Usually, investments are judged by the value they create, but biosecurity is less about generating income than about preventing loss, and it’s hard to put a number on the economics of something that didn’t happen.

However, the DAFF tasked CEBRA with doing exactly this. “We spent a lot of time working on a project to estimate the market and non-market value of Australia’s biosecurity,” said Robinson. “The results have implications for how biosecurity plays out in a connected system.”

His team modelled the arrival, establishment, and spread of 40 biological hazards over 50 years at annual intervals and at a 2 500-metre spatial resolution. Each scenario was simulated 50 000 times, and the results were aggregated to compare outcomes with and without the biosecurity system in place.

“We projected that the total damage from invasive species over 50 years would be just over AUD600 billion,” said Robinson. “We think the Australian biosecurity system protects us from about half of that, or AUD314 billion.”

According to the CEBRA analysis, the average return on the Australian government’s biosecurity investment is 30:1.

Additionally, the model can now be used to zoom in on risks specific to sectors, commodities, pathways, and provinces. It can also resolve counterfactuals, such as the value of increasing the total biosecurity budget, allocating the budget differently, modifying interventions, or conducting research.

Science meets policy

Robinson shared several lessons learned during their modelling and other projects. One insight is that framing biosecurity as an amplifying investment is more powerful than trying to scare the public and legislators with the spectre of invasive pests or diseases.

He also cautioned researchers against gathering facts like philatelists collect postage stamps. Instead, researchers must obtain actionable intelligence, which requires learning who makes decisions, and when, where, and how they decide.

To influence decision-makers whilst remaining flexible, Robinson suggests conducting small case studies that showcase solutions to concrete problems.

When it comes to data analysis, Robinson urged the audience to work with what they have. “It’s almost invariably too late to get more data. We can accommodate the shortcomings of the data we have in the modelling process,” he said. “Waiting to get more data tomorrow when we must act today is a terrible strategy.”

Lastly, Robinson emphasised the need to sustain stakeholder engagement between projects. “There must be a mechanism so that the Australian or New Zealand government can call me up when they have a problem, whether or not I’m doing a project for them.”

He concluded with a quote from the late American mathematician and statistician John Tukey (who coined the term software for computer programmes). “It’s better to solve the right problem approximately than the wrong problem exactly,” paraphrased Robinson.

When it comes to biosecurity systems, he thinks building higher walls is likely to waste energy on the wrong problem. We must instead think beyond border controls.

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Watch this presentation on the Hortgro YouTube channel.