Eight Weird and Wondrous Discoveries From 2023

Life on the Great Pacific Garbage Patch, the true power of nature sanctuaries and more wild discoveries from the Smithsonian Environmental Research Center.

Black monkey perches in a tree staring directly at camera
Howler monkey (Alouatta), a group of primates that includes several vulnerable or endangered species. Protected lands are helping slow the declines of many at-risk species, one of several optimistic discoveries from 2023. Marylin Veiman Echeverria

Animals that can thrive on floating trash. A possible origin story for toxic mercury in our food web. The real power of protected areas, and the secret to a successful forest. This past year had its fair share of jaw-dropping moments for the scientists at the Smithsonian Environmental Research Center (SERC). Here are eight of our favorite discoveries from 2023—from the hopeful and inspiring to the utterly bizarre.

Fisherman stands on a boat, throwing a net into the water
A fisherman throws a net over Rock Cay in Utila, Honduras. Luciano Candisani

Ocean sanctuaries combat poverty on land. Humanity has a vested interest in conserving the ocean. After all, we depend on its bounty for 17% of the world’s animal protein, among a host of other benefits. This year, ecologists discovered marine protected areas—places where fishing is restricted or prohibited—can increase the well-being of people living near them and simultaneously help fish populations. In the Mesoamerican Reef, marine protected areas with the strongest regulations raised relative household incomes of neighboring communities while boosting fish biomass. Children in those communities were also roughly half as likely to suffer stunted growth, a key sign of food insecurity. Understanding how and where these co-benefits occur will be important for developing future protected areas, to ensure they are both effective and equitable.

A blue, donut-shaped piece of plastic coated with pink barnacles and a white gooseneck barnacle. A yellow ruler rests above it for scale, showing the blue plastic is about 6 centimeters in diameter.
Plastic debris with a mix of coastal barnacles (pink and striped) and a gooseneck barnacle from the open ocean SERC Marine Invasions Lab

Coastal creatures are flourishing in the Great Pacific Garbage Patch. Floating plastic pollution is creating a new habitat in the open ocean, one where coastal animals can prosper. In a new study, ecologists analyzed 105 pieces of debris from the Great Pacific Garbage Patch. They found hundreds of marine invertebrates, belonging to 37 groups which they once thought could survive only on the coasts. The discovery heralds a new era in efforts to fight invasive species, when animals can cross entire oceans on plastic rafts. It’s also a shakeup for once-stable ecosystems on the high seas: The newcomers are grabbing space from ocean-open animals and occasionally even eating them.

Two scientists in bright green and blue shirts stand in ankle-deep water, in a patch of small green mangrove plants. The one on the left holds a long metallic pole.
Belize scientists Kent Garbutt (left) and Reynel Blanco take measurements in a mangrove wetland. Jonathan Lefcheck/SERC

Belize claims its place on the blue carbon stage. In the Central American nation of Belize, conserving mangrove plants is a key part of the country’s climate strategy. Besides protecting the shoreline from hurricanes, mangrove ecosystems store more than four times as much carbon as other tropical forests, making them an important tool in climate change mitigation. For the past two years, SERC ecologists have worked on the ground with Belizean scientists and other partners as part of the Belize Blue Carbon Project. In spring of 2023, they reported Belize’s mangroves can store 25.7 million metric tons of blue carbon—the carbon in aquatic ecosystems like mangroves and other wetlands. That’s roughly equivalent to the annual emissions of nearly 21 million cars. This kind of country-specific data is rare, and it's empowering Belize to become a major player on the international climate stage.

A lush, low-lying green wetland juts out into a clear body of water, with a silver stream bisecting the green terrain
Theler Wetlands Nature Preserve, a tidal marsh in Washington State. Joe Mabel via Flickr under CC license BY-SA-4.0

We can fight climate change by reconnecting wetlands to the sea. Like mangroves, wetlands are widely hailed as carbon-storing juggernauts. But some wetland microbes—mainly in wetlands with more freshwater than saltwater—emit methane, a greenhouse gas up to 45 times more powerful than carbon dioxide. And many once-salty wetlands along the coast have been cut off from the sea by dams or other human structures. Last fall, SERC’s coastal carbon scientists created a map of tidal wetlands that have been “artificially freshened” thanks to these impoundments. They showed the U.S. could slash its methane emissions by the equivalent of 1 million metric tons of carbon dioxide, just by restoring normal tidal flow to its disconnected wetlands. The even better news? 18% of those wetlands are already slated for restoration.

Yellow frog with black eyes sits on crisscrossing strands of bright green plants
Hourglass treefrog. Amphibians, which face some of the steepest declines worldwide, also enjoy some of the biggest benefits to living in protected lands. Justin Nowakowski

Vertebrate animals are nearly five times safer in protected lands. World governments are racing to fight the biodiversity crisis. Nowhere is this more evident than the historic agreement to protect 30% of Earth’s land and water by 2030. However, there hasn’t been much evidence as to whether protected areas actually slow declines of animals on land—it’s widely just assumed. For a large-scale test, SERC focused on land-dwelling vertebrates: amphibians, birds, reptiles and mammals. Scientists gathered data for over 1,000 species worldwide. On average, vertebrates declined just 0.4% per year inside protected areas—nearly five times more slowly than vertebrates outside protected areas (1.8% per year). For perspective, that means populations outside protected lands could see their numbers cut in half in just 40 years. Meanwhile, it would take 170 years for a population inside a protected land to undergo the same fate—buying us vital time to stop extinctions.

Plot of trees of diverse heights and shapes, beneath a cloudy blue sky
A 12-species plot at BiodiversiTREE at the Smithsonian Environmental Research Center Susan Cook-Patton

Tree diversity gives forest restorations a better shot at success. When people talk about climate change solutions, planting trees often rises to the top. And yet, nearly all forests planted by humans contain just one species—a risky setup if a pest or disease passes through. SERC’s BiodiversiTREE forest experiment, which turned 10 years old last year, sought to shake up that convention. With nearly 20,000 trees in various 1-, 4- and 12-species combos, scientists could watch forests grow from scratch and see whether diversity matters. Last spring, the first published results came out. Single-species plots were prone to “boom or bust,” with tree survival anywhere from 21% to 99%. Meanwhile, diverse plots were roughly twice as stable on average. Forest restoration follows the same rules as the stock market: Don’t put all your trees in a one-species basket.

Black and white microscopic image showing worm-like strands of bacteria
Pseudodesulfovibrio mercurii ND132, once called Desulfovibrio desulfuricans ND132T, a bacterium that can turn mercury into methylmercury. Oak Ridge National Laboratory

There may be a reason bacteria evolved to make mercury even more toxic. First, a disclaimer: The mercury that’s most famous for contaminating seafood isn’t really mercury. It’s methylmercury, a neurotoxin formed when bacteria take pure mercury (Hg) and combine it with a special carbon molecule called methyl (CH3). But why would bacteria evolve to do this in the first place? Possibly to resist another toxin: arsenic. While examining bacterial genes responsible for making methylmercury, SERC’s microbial ecologists found those genes are right next to genes for arsenic resistance. True to form, when they raised arsenic levels in lab, bacteria began churning out more methylmercury. This discovery suggests by searching for arsenic pollution, we could pinpoint more methylmercury hot spots in nature. And cleaning up those sites could be a double win: getting rid of a deadly carcinogen and keeping more methylmercury out of our food.

A scientist in field clothes and an orange hat stands in a wetland surrounded by green Phragmites reeds roughly twice as tall as she is.
Christine Rohal, a University of Florida scientist and lead author of the study, stands in a patch of Phragmites australis reeds. David England/Farmington Bay Wildlife Management Area
We can still fight invasive Phragmites—if we choose our battlegrounds wisely. There’s still time to defeat Phragmites australis, an invasive reed running rampant throughout the U.S., including Chesapeake Bay wetlands. But controlling Phragmites isn’t easy, and it can’t be done everywhere. In one of SERC’s first studies of 2023, ecologists spent three years actively suppressing Phragmites at various sites throughout Maryland. They saw the biggest success at sites with diverse native plants nearby, that were ready to move in when Phragmites was gone. Targeting sites with fewer, smaller Phragmites patches can also yield big payoffs, as these sites could ultimately become refuges for native plants. However, ongoing treatment is critical. One-and-done treatments are never enough with Phragmites. Deciding where to fight this invader is a question of resources and triage.