You can’t put a price on the oceans. Or can you?

How much are the oceans worth? About $24 trillion (€21.8 trillion). That’s according to marine scientist Ove Hoegh-Guldberg, director of the University of Queensland’s Global Change Institute in St Lucia.

As part of a World Wildlife Federation report, Reviving the Ocean Economy, the author placed an overall monetary value on the seven seas in an effort to help revive conservation and to propose new steps for its safeguarding.

In an interview with the journal Nature, Hoegh-Guldberg explained how he came up with the figure, which was based on the calculation of ocean assets such as fisheries, shipping lanes and tourism as well as the annual value of their outputs.

The report “comes up with a very large number despite the fact that we can’t value the many intangibles: production of sand along coastlines, the value of oceans in terms of their contribution to cultures, and so on,” he said. “We don’t make any apologies for the fact that we can’t get the real value. But we can get a number which we know is the minimum, and in this case it is a very large number . . . I’ve been involved in collaborations in the past with government, and you really do need defendable numbers.”

At that figure, the oceanic economy would be the seventh largest in the world, on a par with the drought-ridden state of California.

This economic approach to science isn’t new. As much of the political will that underpinned environmental advocacy in previous decades declines, sections of the green community have often called for more tangible illustrations of the economic contribution of nature and its services. Some have gone further than broad value calculations and suggested establishing tradable prices for ecosystem services, using the rather risky argument that markets might succeed where politics has not.

The question is: should scientists be playing the role of economists?

"As crude as it seems, putting a price tag on nature, and in this case on our oceans, is necessary in order for people to understand its importance," says Dannielle Senga Green from the biochemistry research group at Trinity College Dublin. "As the authors say, this is an underestimation. The figure only takes into account direct outputs.

“We have to be cautious that habitats which do not provide directly marketable goods are not overlooked as being unimportant. It may be that the services they provide are not fully understood and cannot be assigned a price tag but are nonetheless vital to sustaining a healthy Earth.”

The ‘science’ of economics?

Macroeconomic research is often based in no small part on assumptions. Assumptions in science are frequently made after hard data has been collected, not before.

“In normal economics, numbers assume a working market: multiple working buyers and multiple working sellers,” says Prof Michael Bruen, director of the Centre for Water Resources Research at UCD. “When we talk about something like the value of oceans, any market-based value is gone.”

Value is relative, which raises another, perhaps counterproductive tinge to the “monetisation of nature” approach.

“The report says we must conserve the oceans because they are worth this huge amount of money,” says Bruen. “Once numbers get beyond a certain size though, do they really matter to us any more? Our sensitivity to those numbers decreases as they get bigger, particularly when we’re talking in the trillions.”

Raising awareness

Flawed as it may appear, monetising nature is essentially another attempt by conservationists to draw attention to the importance of ecosystems on levels above the cultural or aesthetic.

If done with smaller natural phenomena, such as the value of wild salmon to a coastal town, or of pollinating bees to agriculture (see panel), perhaps more useful outcomes can be realised.

“A specific example, and one relevant to Ireland, may be peatlands,” says Senga Green. “In a case study in Canada in 2013, it was estimated that for nine ecosystem services that were valued, the peatlands in Manitoba, Canada, provided $128 million [€114 million] per year.”

“I think this approach is necessary because it’s good for us to start thinking about numbers in that respect,” says Dr Jens Carlsson from the UCD school of biology and environmental science.

“We have to communicate the value – natural, aesthetic or economic – that we detect in these particular ecosystems. Scientists are generally reluctant to put a monetary price on things, but when it comes to the meaning of something, and you don’t have a value for it, it’s harder to defend.”

PRICELESS: HONEY FOR NOTHING AND BEES FOR FREE

The value of bees is widely recognised. From their role in honey production and pollination to their frequent positive presence in modern pop culture, it’s pretty clear we need them.

In 2012, researchers from the University of California, Berkeley, went one step further and demonstrated just how valuable they are to the agricultural economy. The study concluded that Californian agriculture gained up to $2.4 billion (€2.1 billion) per year in economic value from wild, free-living bee species. They were doing a job no human or machine could do: the critical function of pollinating crops.

Farmers are already well aware of the economic importance of bees to their livelihoods (more than 30 per cent of the value of agriculture in California comes from crops that are dependent on pollinators). So much so that many use European honeybees to guarantee a good yield.

What they didn’t realise, however, was that wild pollinators were also a significant help to the local economy, providing up to 40 per cent of all pollination services to Californian crops.

Lynn Huntsinger, a professor of rangeland management at University of California, Berkeley, explained why the findings were so significant. “This evidence of economic symbiosis makes it clear that rangeland conservation cannot be separated from the needs of agriculture, whether it is farming or ranching.”