The effects of climate change repeatedly have been linked to societal cornerstones such as agricultural production, human health, and migration. Now, researchers have proposed that crime, specifically maritime piracy, is yet another sphere affected by our changing climate. Shifting water temperatures near East Africa and the South China Sea are affecting fish production and, in turn, driving some fishers to seek a livelihood in other ways.
The Ever Present Risk of Piracy
For as long as ships have been plying the sea, piracy has been a risk. This is particularly true now given the plethora of goods that are transported by ships, said Gary LaFree, a criminologist at the University of Maryland, College Park. “Something like 90% of the world’s goods that are exported and imported move across the ocean.” Since 2000, several hundred pirate attacks have occurred on average each year across the globe.
The individuals responsible for those attacks often have a background in fishing, previous research has shown. That makes sense, said Bo Jiang, a criminologist at the University of Macau in China. When fish production is low, fishers need an alternative source of income, and they already possess seafaring skills, Jiang said. “Whether a fisherman turns into a pirate is largely dependent on fish.”
That connection between crime and fish production prompted Jiang and LaFree to investigate whether changes in the risk of maritime piracy could be tied to environmental shifts brought on by climate change. The researchers decided to focus on two known hot spots of maritime piracy: the Indian Ocean off the east coast of Africa and the South China Sea. The regions’ narrow waterways offer vessels less room to maneuver, often forcing them to slow down.
More Fish, Fewer Fish
Jiang and LaFree mined measurements from the NOAA Extended Reconstructed Sea Surface Temperature database. The temperature of the surface of the sea has been steadily increasing since the turn of the 20th century, and it’s believed to be a key indicator of climate change. The researchers also compiled fish production information from the Food and Agriculture Organization of the United Nations, and they tabulated more than 2,900 instances of maritime piracy that occurred between 1995 and 2013 from the International Maritime Organization’s Global Integrated Shipping Information System database.
The researchers first showed that total annual fish production in both East Africa and the South China Sea was correlated with sea surface temperature. But between the locations, the correlations were opposite in sense: As sea surface temperature increased, fish production decreased in East Africa but increased in the South China Sea. That was an unexpected finding, but it was serendipitous, LaFree said. “We got to look not only at what happens when fish production declines but what happens when it increases.”
Jiang and LaFree showed that the frequency of piracy attacks in both East Africa and the South China Sea was correlated with total annual fish production in each region: When fish production went down, piracy attacks became more frequent, and vice versa. Those trends persisted even when the researchers accounted for potentially confounding variables such as the presence of security guards on board a ship and the political stability of nearby countries. These results were published in Weather, Climate, and Society.
Climate, Conflict, and Crime
It makes sense that environmental shifts could possibly push some fishers to become pirates, said Jade Lindley, a criminologist at the University of Western Australia in Perth who was not involved in the research. “Opportunities for employment are going to change because of climate change.”
But it’s also not true that all pirates have a background in fishing, said Lindley, who has studied maritime piracy near Somalia. When piracy is particularly lucrative, it tends to attract people from all walks of life, Lindley explained. A lull in fish production near Somalia in the 2000s drove a rise in maritime crime, and “it brought people in who had never seen the ocean,” she said.
In the future, Jiang and LaFree plan to investigate whether there’s also a link between climate change and land-based conflicts like terrorism. The imprint of climate change might be subtle, but these new results demonstrated that it’s worth looking for, LaFree said. “I just assumed, going in, that climate change was moving too slowly to affect something as dynamic as crime.”
—Katherine Kornei (@KatherineKornei), Science Writer