When to Watch Closer: New Study Shows Monitoring Becomes More Valuable as Populations Near Collapse

We addressed a major challenge in sustainability science: identifying targets that maximize ecosystem benefits to humanity while minimizing the risk of crossing critical system thresholds. Researchers led by Adrian Stier at UC Santa Barbara tackled a deceptively simple question: how much monitoring is enough?

In natural resource management, high-precision monitoring costs serious money, requires analysis of large datasets, and can delay decision-making. But insufficient monitoring risks missing warning signs before populations crash past critical thresholds. We built a closed-loop management strategy evaluation, essentially a virtual laboratory where they could harvest populations over 50-year periods and observe outcomes under different monitoring scenarios.

We ran 10,000 replicate simulations, testing how monitoring precision affected both the risk of population collapse and the economic value managers could extract. They focused on populations with critical biological thresholds, points where population growth rates become negative, leading to what scientists call depensation.

"But insufficient monitoring risks missing warning signs before populations crash past critical thresholds."

Our results revealed a clear pattern: the value of monitoring information increases as populations spend more time near critical collapse thresholds. This benefit emerged because higher monitoring precision promoted both higher sustainable yield and greater capacity for populations to recover from overharvest. When populations were safely above their danger zones, basic monitoring worked adequately. But as they approached critical thresholds, precise monitoring became exponentially more valuable.

Our findings suggest that precautionary buffers triggering increased monitoring precision as resource levels decline may offer a way to minimize monitoring costs while maximizing profits. Our research provides a framework for making tough decisions about monitoring investments, with implications extending beyond fisheries to any harvested resource, from wildlife to forests, where critical thresholds might exist.

However, significant challenges remain. Scientists still struggle to identify where critical thresholds actually exist in real populations, or to predict how environmental changes might shift their locations. The computer simulations provided a clean proof of concept, but the harder work lies ahead in seeing whether these insights can prevent real-world collapses.

Citation

Stier, Adrian C.; Essington, Timothy E.; Samhouri, Jameal F.; Siple, Margaret C.; Halpern, Benjamin S.; White, Crow; Lynham, John M.; Salomon, Anne K.; Levin, Phillip S. (2022). Avoiding critical thresholds through effective monitoring. Proceedings of the Royal Society B: Biological Sciences.

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This paper is Open Access.