The more money that is spent on recovery efforts for an endangered or threatened species, the more likely that species is to recover. It’s an intuitive link, although intuitive links aren’t always borne out by reality. But in the US, where a large amount of funding for endangered species recovery efforts comes from the government, the money being spent often falls well short of what's needed, leaving many species to flounder.

Arizona State University researcher Leah Gerber has analyzed government spending on endangered species, finding ways to make the process more efficient. She found that some species are declining despite receiving more funding than they request, making them “costly yet futile,” she writes in a PNAS paper. Redirecting this extra funding could help us to save many more species.

There are currently around 1,500 species listed as endangered or threatened in the US, half of which are at high risk for extinction. The US Fish and Wildlife Service is set to assess approximately 800 more species for inclusion in the list within the next two years. The recovery plans for these species require $1.21 billion/year, but in reality, only a quarter of this budget is actually spent. It’s a “capacity challenge”, Gerber writes—the funding that's made available for recovery efforts is just not sufficient to meet the flood of demand.

The spending is also disproportionate. Only around 12 percent of the species on the list are receiving the full amount of funding requested in their recovery plans, but a number of these actually receive a surplus. Although the species that get adequate funding are far more likely to be recovering, there are some species that receive sufficient funding but aren’t doing all that well.

To look at this more closely, Gerber divided recovery efforts into four categories based on funding and recovery progress. The ideal “cost-effective” group is what we should be aiming for with every endangered species: enough funding and evidence of recovery. But two groups had evidence of overspending. One was the “costly success” group that showed evidence of recovery but had more funding than needed. The second was a “costly failure” group that had adequate funding but wasn’t showing evidence of recovery.

“The declining species within the top 50 spending surpluses command a (surplus) budget of more than $17 million/year,” she writes. For context, if you take the full budget and divide by the 1,500 endangered and threatened species, you get about $800,000 per species.

The fourth group is the one that desperately needs attention: the “injurious neglect” group is underfunded and not showing evidence of recovery. More than 100 of these species are receiving “less than 10 percent of the investment needed,” Gerber reports.

Previous efforts to redistribute conservation funding have been criticized because they effectively ask the government to abandon certain species. This finding could introduce a more palatable alternative: cutting just the surplus funding from some species and redirecting it towards the "injurious neglect" group. This could bump up the funding for up to 182 species that are currently underfunded.

An important question to ask here is whether there’s some important difference between the overfunded and underfunded groups. Gerber looked at one candidate for this difference: the kinds of species in each group. Of the 182 species that would benefit from reallocation of funding, more than half are plants, and the majority of the rest are the kinds of animals that attract less attention for conservation efforts: invertebrates, fish, reptiles, and amphibians. These proportions aren’t significantly different to the overfunded species, though, so this doesn't seem to be a factor.

While the changes advocated here seem to make sense, before implementing them, it’s important to do more analyses of what the changes are likely to produce. However, improving efficiency in this process seems to be an obvious choice. “The careful work that goes into creating recovery plans will be useful only if the recommended recovery actions are implemented and funded,” Gerber writes. As it stands, a lot of labor—and species—are going to waste.

PNAS, 2016. DOI: 10.1073/pnas.1525085113 (About DOIs).