Tanzania’s marine reserves offer long-term benefits to communities, study finds

Marine protected areas in Tanzania boosted living standards in nearby communities over a span of nearly 20 years, a recent study in Conservation Letters found.

Near MPAs, living standards improved, and there was a shift away from agricultural work, said study author Julia Girard, a Ph.D. student in environmental economics at the University of Montpellier, France.

How marine reserves fare in conservation and community development is an important question for Tanzania, where 20% of the population is heavily dependent on fisheries for food and income.

The country established five multiuse MPAs in the 1990s, which allow fishing with additional rules designed to promote sustainability. Scientists have identified MPAs where regulated fishing activity is permitted as powerful tools to help Tanzania and other nations protect 30% of their oceans by 2030 without denying fishers their livelihoods.

To see how these MPAs have impacted local development, the research team surveyed 840 households in 24 villages in 2021, asking questions about employment, fishing history, standard of living, and perceptions about the marine reserves. They then compared the data with the results of a similar survey conducted in 2003. This is one of just a few studies documenting the long-term impacts of multiuse MPAs on local development.

All villages surveyed saw their living conditions, as measured by 18 variables including home ownership, food security and access to refrigeration, improve between 2003 and 2021. But residents in settlements within 5 kilometers (3 miles) of a protected area saw their standard of living improve significantly more than communities living more than 10 km (6 mi) away, as captured by the authors’ living standards metric.

Their results reflect a change from the 2003 survey, which found few differences in living standards between communities close to or far from MPAs. At the time of the fieldwork, the MPAs were only three to eight years old.

The authors couldn’t connect the greater improvements in living standards to better fishing opportunities arising from protections. Rather, an increase in jobs beyond fishing and farming coincided with material improvements in their lives.

These findings differ from a review of marine reserves in Central America, which found the region’s MPAs primarily benefit people by preserving or boosting fish populations.

The study suggested that the increase in living standards came from the growth of industries beyond fishing and farming, which only occurred in communities near an MPA. The authors hypothesized that this trend is driven by tourism. Visitors snorkel and dive the coral reefs, then buy locally made products like seaweed soaps, said study co-author Narriman Jiddawi, a marine biologist at Zanzi Marine and Coastal Solutions in Zanzibar, Tanzania.

The impact of tourism is especially visible on the eastern shore of Unguja, the largest island of the Zanzibar archipelago off the Tanzanian coast. Every year, hundreds of thousands of people come for its white sand beaches and teal ocean.

Increased tourist footfall transformed the island’s job market over the course of the study, and living standards grew especially rapidly in villages that were reliant on tourism.

“With the data we have, we can’t prove that the change we see is due to tourism,” Girard said. “But that’s one possibility.”

The authors also lacked data to determine the ecological impact of the waves of tourists, but Jiddawi noted that swarms of divers might be damaging coral reefs.

Independent of the impacts of tourism, the country’s fisheries are facing a concerning decline.

People from the 24 villages surveyed reported catching fewer fish each day on the water in 2021 compared to 2003. The study found that villages close to MPAs experienced the same decline in daily fish catches as people living farther away. Most of the residents surveyed said the MPAs had no impact on the number of fish they caught.

Localized studies of multiuse MPAs in Tanzania show their impacts on fish populations vary. In most cases, researchers do not directly measure fish population sizes but instead examine fishers’ catches. One study found that fishers inside Mnazi Bay Marine Park bagged four times as much seafood in 2010 than in 2006.

Another study sampled catches brought ashore from October 2019 to March 2020. Boats inside two Tanzanian marine parks landed fewer fish than those in nearby unprotected waters, but fish taken from parks were larger, on average. Marine park regulations reduced the number of fish caught and helped more young fish survive to maturity, the authors posited.

MPA rules regulating fishing may not be enough to alleviate the enormous pressure on marine ecosystems.

Between 2000 and 2020, the human population probably doubled, and climate change increased, said David Obura, a coral reef scientist and founder of CORDIOAE, a marine conservation nonprofit in Kenya. “So, the pressures driving the recent decline [in fish numbers] are only increasing.”

The recent study highlights that a single intervention can give rise to multiple impacts in different areas, said Obura, who wasn’t involved in the research.

“Putting in place protected areas has not necessarily improved the productivity of the fishery,” he said, “but it has diversified income.”

This story originally appeared in Mongabay