The concept of a tipping point or turning point was first used by social scientists in the 1950s but gained currency with the publication of a popular book on the subject by Malcolm Gladwell in 2000. The Merriam-Webster definition is “the critical point in a situation, process, or system beyond which a significant and often unstoppable effect or change takes place.” The basic idea is that a transition to a state of disequilibrium, sometimes called a “non-linear regime shift,” occurs after a threshold of conditions is passed.

The subtitle to Gladwell’s book is “how little things make a big difference.” Metaphorically a tipping point can be considered the straw that breaks the camel’s back, the point of no return. There may be some value in considering the various ways tipping points apply to aquaculture at various scales.

At the level of individual production units — ponds, cages, tanks — the tipping point can be loosely related to carrying capacity, with safe and high risk zones of operation. The concept is probably better applied to aquaculture in terms of their supporting ecosystems. There are numerous examples of boom-and-bust cycles in aquaculture where too many farms are placed in an area and the capacity of the ecosystem to provide supporting services is exceeded. Examples of excessive development of cages in lakes and coastal shrimp farms come to mind.

Managing aquaculture development in a way that does not lead to deleterious ecosystem change — often associated with eutrophication — is a serious governance challenge, especially because the causes of change most often cannot be attributed solely to aquaculture development. The Ecosystem Approach to Aquaculture, developed and promoted by the FAO and the World Bank, can provide meaningful guidance on aquaculture development in a way to avoid ecological tipping points through prudent application of the precautionary principle.

There is fascinating research underway to understand ecological tipping points. Ecosystems approaching tipping points become unstable and more variable, especially if they lack resilience capacity. When the tipping point occurs, the system shifts from one stable state to another, such as would occur in a shallow lake that would shift from dominance by phytoplankton to dominance by aquatic macrophytes.

At the biosphere level, the concept of tipping points has also been applied to climate change. Previously in this column (March 2016), I discussed planetary boundaries and the idea of a “safe operating space for humanity.” For various anthropogenic drivers, we have begun to push up against regional boundaries of this safe space. The concern is related to undesirable and unpredictable change past a certain point. Despite attempts to limit CO2 accumulation to 350 ppm, it appears that we are destined to live in an environment with at least 450 ppm, resulting in an average temperature increase of 2 C. The consequences of such a change to every facet of life will be difficult for most and dire for many. Potential climate change tipping points include melting of the ice in the Arctic Sea and Greenland, break-up of the West Antarctic ice sheet, a permanent El Niño, and loss of forests in the Amazon and high-latitude northern areas, and changes to ocean circulation patterns.

At the level of sector development, a tipping point can be reached when there is a critical mass of producers — the magic number seems to be around 150 — in an area. In places with successful aquaculture “industries,” there is a cluster of producers, along with other critical parts of the value chain — hatcheries, feed mills and processing plants. Individual aquaculture farms that are dispersed and few do not allow the positive feedback that creates conditions favorable for development of a true sector.

One negative example of a tipping point may have occurred recently with the legislature of the State of Washington (US) voted to ban salmon aquaculture in response to an incident involving escaped salmon from net pens belonging to Cooke Aquaculture. In Washington, salmon farming has been hanging by a thread for at least a couple of decades now, with barely any expansion and only a few operations. When Cooke was called to account, and the response was considered inadequate, it seemed an easy matter politically to remove the nuisance by imposing the ban. It’s possible that making such a policy decision would have been more difficult with a greater number of producers.

In Gladwell’s book, tipping points refer to how ideas succeed in spreading and how positive feedback loops can be used to foster change. Gladwell proposed three factors that affect the probability of an idea’s success. First is the “Law of the Few,” where a few key categories of people must act as proponents of an idea. Next is what he calls the “stickiness” of an idea in the brain. Finally, the “Power of Context” is the social environment and historical and cultural context that provides fertile ground for an idea to take hold.

In “telling our story,” the theme of the recently concluded Aquaculture America, we have an idea that is potentially sticky, based on the nutritional benefits of seafood consumption and the comparative resource efficiency of aquaculture compared to other forms of animal protein production. There are also the categories of people in aquaculture who can spread the word and make connections. The Power of Context seems to be key. In places like the US, the socio-cultural environment for aquaculture as an economic activity is not as welcoming as in countries in Asia with well-developed aquaculture sectors.

At every level discussed here, being able to forecast changes before they occur and understanding thresholds of change can inform actions that prevent crop loss, avoid degradation of the ecosystems that support aquaculture, and allow us to operate within the safe zone of planetary boundaries. We need good indicators to be able to anticipate critical transitions and respond with conviction to early warning signals of undesirable change. — John A. Hargreaves, Editor-in-Chief