9.20.25

Salmonberries in our future

Picking salmonberries is a cultural tradition for many Alaskans.

The activities are as follows:

In the Yup’ik and Cup’ik Native communities of western Alaska, berry picking is a deeply rooted tradition. Many villages are located more than 500 miles from the nearest road system or grocery store. Fresh fruits and vegetables from other places are flown in by small planes at significant cost. This makes local berries a lifeline for these remote villages.

Salmonberries (also known as cloudberries) are one type of Arctic berry. They are prized for their wonderful taste. Salmonberries are rich in nutrients like vitamin C, antioxidants, and essential minerals. One cup of salmonberries alone can meet a person’s daily vitamin C needs. In addition to humans, these berries provide nutrients to other animals, such as migrating birds, small mammals, and bears.

During berry season, families travel across the land to gather berries, preserve them, and store them for the winter. Families use a vast web of winding rivers to travel by boat to reach their berry picking camps. These western Alaska rivers flow towards the Bering Sea, where freshwater mixes with salty ocean tides.

This mix of saltwater and freshwater shapes the tundra landscape. Tough, salt-tolerant plants, like grasses and sedges, often dominate low-lying areas closest to the sea. Slightly higher ground, just above the reach of the tides, provides a more suitable home for berries. These subtle shifts in water levels play a large role in determining where berries can grow.

Salmonberry ready to be picked.

Ecologists Karen, Katharine, and Joshua are collaborating with Native communities to learn more about how changes in climate are affecting berry plants. They are studying two major changes already observed under climate change – warming and flooding. Over time, warming and flooding combined could change the entire makeup of plant communities. This will affect whether local families are able to continue their traditions and access this valuable food source.

Alaska’s average temperatures are increasing, more so than other parts of the globe. This warming might help some plants by extending the growing season. With more time and sunlight, salmonberries and other plants may actually grow faster.

Climate change is also expected to increase flooding in some areas of coastal Alaska. Storms are already becoming stronger and more frequent, pushing seawater farther inland. Because of this, flooding events are increasing in frequency. Rising sea levels and storm surges may kill salmonberry plants because these plants are not adapted to having their roots submerged in salty water. They used this water to simulate flooding events in the plots. In the end, their experiment had four different types of plots: (1) Control plots with no warming or flooding, (2) plots that were warmed, (3) plots that were flooded, and (4) plots that were both warmed and flooded.

To tease apart the effects of warming and flooding, Karen, Katharine, and Joshua designed a field experiment to simulate climate change. They built clear plastic structures, called open-topped chambers, to trap heat and raise the temperature by about 2°C. These chambers can be thought of as mini time machines, creating small areas that have the expected temperatures of the coming decades. Next, they created flooded plots using brackish, or slightly salty, water that they collected where the fresh river water meets the sea.

They let these treatments run the full growing season. After that time, the team collected data on salmonberry growth. Karen, Katharine, and Joshua measured both the height and biomass of salmonberry plants in all of the plots. These two measures are good estimates of how many berries the plants will produce – the larger the plant, the more berries it can make. They were very precise in their measurements; in a place where food and traditions are tied to the land, every berry matters.

Featured scientists: Karen Beard (she/her) of Utah State University, Katharine Kelsey (she/her) of the University of Colorado Denver and Joshua Leffler (he/him) of South Dakota State University. Written by: Andrea Pokrzywinski (she/her).

Flesch–Kincaid Reading Grade Level = 5.7

8.1.24

Poop, poop, goose!

Cackling Goose next to a pile of goose poop, or feces
Cackling Goose next to a pile of goose poop, or feces. Photo by Andrea Pokrzywinski.

The activities are as follows:

Each spring, millions of birds return to the Yukon-Kuskokwim Delta. This delta is where two of the largest rivers in Alaska empty into the Bering Sea. It is also one of the world’s most significant habitats for geese to breed and raise their young. 

With all these geese coming together in one area, they create quite a mess – they drop tons of poop onto the soil. So much poop in fact, that scientists wonder whether poop from this area in Alaska could have a global impact! Climate change is a worldwide environmental issue that is caused by too many greenhouse gasses being released into our atmosphere. Typically, we think of humans as the cause of this greenhouse gas release, but other animals can contribute as well. 

When poop falls onto the soil it is decomposed by bacteria. Bacteria release methane (CH4), a potent greenhouse gas. The more geese there are, the more poop they will produce and the more food there will be for soil bacteria. By increasing the amount of greenhouse gasses that are released by soil bacteria, geese might actually indirectly contribute to global climate change.

Trisha is an ecosystem ecologist who scoops goose poop for research projects. Her research is looking into whether animals, other than humans, can change the carbon cycle. Trisha teamed up with Bonnie, a fellow ecosystem ecologist. Bonnie studies how matter moves between the living parts of the environment, such as plants and animals, and the nonliving parts. She is especially interested in how bacteria in the soil play a role in the carbon cycle.

Together, the team designed a three-year project to figure out the effects of goose poop on the carbon cycle. Each summer, a large team of researchers spend 90 days camping on remote sites near the Yukon-Kuskokwim Delta. The team scooped up poop from nearby goose habitats to use in their experiments. They set up six control plots where they added no poop and six treatment plots where they added poop. From these twelve plots, the team measured methane emissions from the soil. Methane was measured as methane flux in micromoles, or µM. These data helped them determine how ecosystems respond to geese by measuring whether goose poop affects methane production by soil bacteria.  

Featured scientists: Trisha Atwood of Utah State University and Bonnie Waring of Imperial College. Written by Andrea Pokrzywinski.

Flesch–Kincaid Reading Grade Level = 8.7

Additional teacher resources related to this Data Nugget include:

3.16.23

Benthic buddies

Danny and Kaylie sampling benthic animals

The activities are as follows:

Lagoons are areas along the coast where a shallow pocket of sea water is separated from the ocean most of the time. During some events, like high tides, the ocean water meets back up with the lagoon. Coastal lagoons are found all over the world – even in the most northern region of Alaska, called the High Arctic!

These High Arctic lagoons go through many extreme changes each season. In April, ice completely covers the surface. The mud at the bottom of the shorelines is frozen solid. In June, the ice begins to break up and the muddy bottoms of the lagoons begin to thaw. The melting ice adds freshwater to the lagoons and lowers the salt levels. In August, lagoon temperatures continue to rise until there is only open water and soft mushy sediment.

You would think these harsh conditions would make High Arctic lagoons not suitable to live in. However, these lagoons support a surprisingly wide range of marine organisms! Marine worms, snails, and clams live in the muddy sediment of these lagoons. This habitat is also called the bottom, or benthic, environment. Having a rich variety of benthic animals in these habitats supports fish, which migrate along the shoreline and eat these animals once the ice has left. And people who live in the Arctic depend on fishing for their food.

Ken, Danny, and Kaylie are a team of scientists from Texas interested in learning more about how the extreme seasons of the High Arctic affect the marine life that lives there. They want to know whether the total number of benthic species changes with the seasons. Or does the benthic community of worms, snails, and clams stay constant throughout the year regardless of ice, freezing temperatures, and large changes in salt levels? The science team thought that the extreme winter conditions in the Arctic lagoons cause a die-off each year, so there would be fewer species found at that time. Once the ice melts each year, benthic animals likely migrate back into the lagoons from deeper waters and the number of species would increase again.

Ken, Danny, and Kaylie had many discussions about how they could answer their questions. They decided the best approach would be to travel to Alaska to take samples of the benthic animals. To capture the changes in lagoon living conditions, they would need to collect samples during the three distinct seasons.

Benthic organisms from a sample

The science team chose to sample Elson Lagoon because it is in the village of Utqiaġvik, Alaska and much easier to reach than other Arctic lagoons. They visited three times. First, in April, during the ice-covered time, again in June when the ice was breaking up, and a final time in summer when the water was warmer. In April, they used a hollow ice drill to collect a core sample of the frozen sediment beneath the ice. In June and August, they deployed a Ponar instrument into the water, which snaps shut when it reaches the lagoon bottom to grab a sample. Each time they visited the lagoon, they collected two sediment samples.

Back in the lab, they rinsed the samples with seawater to remove the sediment and reveal the benthic animals. The team then sorted and identified the species present. They recorded the total number of different species, or species richness, found in each sample.

Featured scientists: Ken Dunton, Daniel Fraser, and Kaylie Plumb from the University of Texas Marine Science Institute

Written by: Maria McDonel from Flour Bluff and Corpus Christi Schools

Flesch–Kincaid Reading Grade Level = 8.9

Additional teacher resources related to this Data Nugget include:

1.8.21

To reflect, or not to reflect, that is the question

Jen stops to take a photo while conducting fieldwork in the Arctic.

The activities are as follows:

Since 1978, satellites have measured changes in Arctic sea ice extent, or the area by the North Pole covered by ice. Observations show that Arctic sea ice extent change throughout the year. Arctic sea ice reaches its smallest size at the end of summer in September. Scientists who look at these data over time have noticed the sea ice extent in September has been getting smaller and smaller since 1978. This shocking trend means that the Arctic sea ice is declining, and fast! 

Why does this matter? Well, it turns out that Arctic sea ice plays a major role in the world’s climate system. When energy from the Sun reaches Earth, part of the energy is absorbed by the surface, while the rest is reflected back into space. The energy that is absorbed becomes heat, and warms the planet. The amount of energy reflected back is called albedo.

The higher the albedo, the more energy is reflected off a surface. Complete reflection is assigned a value of 1 (100%) and complete absorption is 0 (0%). Lighter colored surfaces (e.g., white) have a higher albedo than darker colored surfaces (e.g., black). Sea ice is white and reflects about 60% of solar energy striking its surface, so its albedo measurement is 0.60. This means that 40% of the Sun’s energy that reaches the sea ice is absorbed. In contrast, the ocean is much darker and reflects only about 6% of the Sun’s energy striking its surface, so its albedo measurement 0.06. This means that 94% of the Sun’s energy that reaches the ocean is absorbed.

Jen (second from left) preparing to teach her students at the University of Colorado Boulder while working in the Arctic. Photo by Polar Bears International.

Jen first became interested in sea ice in the summer of 2007, when a record low level of sea ice caught scientists off guard. They worried that if the albedo of the Arctic declines, energy that used to be reflected by the white ice will be absorbed by the dark oceans and lead to increased warming. At the time, Jen was working with new satellite observations and found it fascinating to understand what led to the record low sea ice year. To continue her passion, Jen joined a team of scientists studying the Arctic’s energy budget. 

Jen and her team predicted that the decline in the light-colored sea ice will cause Arctic albedo to decrease as well. Jen used incoming and reflected solar energy data to determine the changes in the Arctic’s albedo. These data were collected from satellites as part of the Clouds and Earth’s Radiant Energy System (CERES) project. Then, Jen compared the albedo data to changes in the extent of sea ice from satellite images to look for a pattern. 

Featured scientist: Jen Kay from the Cooperative Institute for Research in Environmental Sciences and the Department of Atmospheric and Oceanic Sciences at the University of Colorado Boulder. Written by Jon Griffith with support from AGS 1554659 and OPP 1839104.

Flesch–Kincaid Reading Grade Level = 9.6