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4.20.16

The birds of Hubbard Brook, Part II

In Part I, you examined patterns of total bird abundance at Hubbard Brook Experimental Forest. These data showed bird numbers at Hubbard Brook have declined since 1969. Is this true for every species of bird? You will now examine data for four species of birds to see if each of these species follows the same trend.

Red-eyed vireo in the Hubbard Brook Experimental Forest

The activities are as follows:

It is very hard to study migratory birds because they are at Hubbard Brook only during their breeding season (summer in the Northern Hemisphere). They spend the rest of their time in the southeastern United States, the Caribbean or South America or migrating between their two homes. Therefore, it can be difficult to tease out the many variables affecting bird populations over their entire range. To start, scientists decided to focus on what they could study—the habitat types at Hubbard Brook and how they might affect bird populations.

Hubbard Brook Forest was heavily logged and disturbed in the early 1900s. Trees were cut down to make wood products, like paper and housing materials. Logging ended in 1915, and various plants began to grow back. The area went through what is called secondary succession, which refers to the naturally occurring changes in forest structure that happen as a forest recovers after it was cut down or otherwise disturbed. Today, the forest has grown back. Scientists know that as the forest grew older, its structure changed: Trees grew taller, the types of trees changed, and there was less shrubby understory. The forest now contains a mixture of deciduous trees that lose their leaves in the winter (about 80–90%; mostly beech, maples, and birches) and evergreen trees, mostly conifers, that stay green all year (about 10–20%; mostly hemlock, spruce, and fir).

Richard and his fellow scientists already knew a lot about the birds that live in the forest. For example, some bird species prefer habitats found in younger forests, while others prefer habitats found in older forests. They decided to look carefully into the habitat preferences of four important species of birds—Least Flycatcher, Red-eyed Vireo, Black-throated Green Warbler, and American Redstart—and compare them to habitats available at each stage of succession. They wondered if habitat preference of a bird species is associated with any change in the bird populations at Hubbard Brook since the beginning of succession.

Least Flycatcher: The Least Flycatcher prefers to live in semi-open, mid-successional forests. The term mid-successional refers to forests that are still growing back after a disturbance. These forests usually consist of trees that are all about the same age and have a thick canopy at the top with few gaps, a relatively open area under the canopy, and a denser shrub layer close to the ground.
Black-throated Green Warbler: The Black-throated Green Warbler occupies a wide variety of habitats. It seems to prefer areas where deciduous and coniferous forests meet and can be found in both forest types. It avoids disturbed areas and forests that are just beginning succession. This species prefers both mid-successional and mature forests.
Red-eyed Vireo: The Red-eyed Vireo breeds in deciduous forests as well as forests that are mixed with deciduous and coniferous trees. They are abundant deep in the center of a forest. They avoid areas where trees have been cut or blown down and do not live near the edge. After an area is logged, it often takes a very long time for this species to return.
American Redstart: The American Redstart generally prefers moist, deciduous, forests with many shrubs. Like the Least Flycatcher, this species prefers mid-successional forests.

Featured scientist: Richard Holmes from the Hubbard Brook Experimental Forest. Data Nugget written by: Sarah Turtle and Jackie Wilson.

Flesch–Kincaid Reading Grade Level = 10.6

A view of the Hubbard Brook Experimental Forest

Additional teacher resource related to this Data Nugget:

There is an engaging video that can be used before the students begin the activity. It introduces some of the researchers behind this body of work, including Richard Holmes, and highlights the importance of the long-term nature of this dataset.
For the full dataset associated with this Data Nugget, check out the Hubbard Brook Data Catalog page. Search for “Bird abundances” in the search bar to find the dataset.
For more information on this research, check out the Hubbard Brook Experimental Forest’s page on their songbird research
For more lessons created from data collected on birds at Hubbard Brook, check out the page “Migratory Birds Math and Science Lessons from Hubbard Brook.”

There are multiple publications related to the data included in this activity:

Holmes, R. T. 2011. Birds in northern hardwoods ecosystems: Long-term research on population and community processes in the Hubbard Brook Experimental Forest. Forest Ecology and Management doi:10.1016/j.foreco.2010.06.021.
Holmes, R.T., 2007. Understanding population change in migratory songbirds: long-term and experimental studies of Neotropical migrants in breeding and wintering areas. Ibis 149 (Suppl. 2), 2-13.
Townsend, A. K., et al. (2016). The interacting effects of food, spring temperature, and global climate cycles on population dynamics of a migratory songbird. Global Change Biology 2: 544-555.

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4.20.16

The birds of Hubbard Brook, Part I

Male Black-throated Blue Warbler feeding nestlings. Nests of this species are built typically less than one meter above ground in a shrub such as hobblebush. Photo by N. Rodenhouse.

The activities are as follows:

The Hubbard Brook Experimental Forest is an area where scientists have collected ecological data for many years. It is located in the White Mountains of New Hampshire. Data collected in this forest helps uncover environmental trends over long periods of time, such as changes in air temperature, precipitation, forest growth, and animal populations. It is important to collect data on ecosystems over time because these patterns could be missed with shorter observation periods or short-term experiments.

Richard Holmes is an avian ecologist who began this study because he was interested in how bird populations were responding to long-term environmental change.

Each spring, Hubbard Brook comes alive with the arrival of migratory birds. Many come from the tropics to take advantage of abundant insects and the long summer days of northern areas. In the spring, avian ecologists, or scientists who study the ecology of birds, also become active in the forest at Hubbard Brook. They have been keeping records on the birds that live in the experimental forest for over 50 years. These data are important because they represent one of the longest bird studies ever conducted!

Richard is an avian ecologist who began this study early in his career as a scientist. He was interested in how bird populations respond to long-term environmental changes at Hubbard Brook. Every summer since 1969, Richard takes his team of trained scientists, students, and technicians into the field to identify which species are present. Richard’s team monitors populations of over 30 different bird species. They count the number of birds that are in the forest each year and study their activities during the breeding season. The researchers wake up every morning before the sun rises and travel to the far reaches of the forest. They listen for, look for, identify, and count all the birds they find. The team has been trained to be able to identify the birds by sight, but also by their calls. Team members are even able to identify how far away a bird is by hearing its call!

The study area is located away from any roads or other disturbed areas. To measure the abundance, or number of birds found in the 10 hectare study area, the researchers used what is called the spot-mapping method. They use plastic flags on trees 50 meters apart throughout the study area to create a 50×50 meter grid. The grid allows them to map where birds are found in this area, and when possible, where they locate their nests. Using the grid the researchers systematically walk through the plot several days each week from early May until July, recording the presence and activities of every bird they find. They also note the locations of nearby birds singing at the same time. These records are combined on a map to figure out a bird’s territory, or activity center. At the end of the breeding season they count up the number of territories to get an estimate of the number of birds on the study area. This information, when paired with observations on the presence and activities of mates, locations of nests, and other evidence of breeding activity provide an accurate estimate for bird abundance. Finally, some species under close study, like American Redstart and Black-throated Blue Warbler, were captured and given unique combinations of colored bands, which makes it easier to track individuals.

By looking at bird abundance data across many years, Richard and his colleagues can identify trends that reveal how avian populations change over time.

Featured scientist: Richard Holmes from the Hubbard Brook Experimental Forest. Data Nugget written by: Sarah Turtle and Jackie Wilson.

Flesch–Kincaid Reading Grade Level = 11.3

A view of the Hubbard Brook Experimental Forest

Additional teacher resource related to this Data Nugget:

There is an engaging video that can be used before the students begin the activity. It introduces some of the researchers behind this body of work, including Richard Holmes, and highlights the importance of the long-term nature of this dataset.
For the full dataset associated with this Data Nugget, check out the Hubbard Brook Data Catalog page. Search for “Bird abundances” in the search bar to find the dataset.
For more information on this research, check out the Hubbard Brook Experimental Forest’s page on their songbird research
For more lessons created from data collected on birds at Hubbard Brook, check out the page “Migratory Birds Math and Science Lessons from Hubbard Brook.”

There are multiple publications related to the data included in this activity:

Holmes, R. T. 2011. Birds in northern hardwoods ecosystems: Long-term research on population and community processes in the Hubbard Brook Experimental Forest. Forest Ecology and Management doi:10.1016/j.foreco.2010.06.021.
Holmes, R.T., 2007. Understanding population change in migratory songbirds: long-term and experimental studies of Neotropical migrants in breeding and wintering areas. Ibis 149 (Suppl. 2), 2-13.
Townsend, A. K., et al. (2016). The interacting effects of food, spring temperature, and global climate cycles on population dynamics of a migratory songbird. Global Change Biology 2: 544-555.

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3.25.16

Keeping up with the sea level

A view of salt marsh hay (Spartina patens) growing in a marsh

The activities are as follows:

Salt marshes are ecosystems that occur along much of the coast of New England in the United States. Salt marshes are very important – they serve as habitat for many species, are a safer breeding location for many fish, absorb nutrients from fertilizer and sewage coming from land and prevent them from entering the ocean, and protect the coast from erosion during storms.

Unfortunately, rising sea levels are threatening these important ecosystems. Sea level is the elevation of the ocean water surface compared to the elevation of the soil surface. Two processes are causing sea levels to rise. First, as our world gets warmer, ocean waters are getting warmer too. When water warms, it also expands. This expansion causes ocean water to take up more space and it will continue to creep higher and higher onto the surrounding coastal land. Second, freshwater frozen in ice on land, such as glaciers in Antarctica, is now melting and running into the oceans. Along the New England coast, sea levels have risen by 0.26 cm a year for the last 80 years, and by 0.4 cm a year for the last 20 years. Because marshes are such important habitats, scientists want to know whether they can keep up with sea level rise.

Researcher Sam Bond taking Sediment Elevation Table (SET) measurements in the marsh

When exploring the marsh, Anne, a scientist at the Plum Island Ecosystems Long Term Ecological Research site, noticed that the salt marsh appeared to be changing over time. One species of plant, salt marsh cordgrass (Spartina alterniflora), appeared to be increasing in some areas. At the same time, some areas with another species of plant, salt marsh hay (Spartina patens), appeared to be dying back. Each of these species of plants is growing in the soil on the marsh floor and needs to keep its leaves above the surface of the water. As sea levels rise, the elevation of the marsh soil must rise as well so the plants have ground high enough to keep them above sea level. Basically, it is like a race between the marsh floor and sea level to see who can stay on top!

Anne and her colleges measured how fast marsh soil elevation was changing near both species of plants. They set up monitoring points in the marsh using a device called the Sediment Elevation Table (SET). SET is a pole set deep in the marsh that does not move or change in elevation. On top of this pole there is an arm with measuring rods that record the height of the marsh surface. The SETs were set up in 2 sites where there is salt marsh cordgrass and 2 sites where there is salt marsh hay. Anne has been taking these measurements for more than a decade. If the marsh surface is rising at the same rate as the sea, perhaps these marshes will continue to do well in the future.

Featured scientist: Anne Giblin from the Marine Biological Laboratory and the Plum Island Ecosystems Long-Term Ecological Research site

Flesch–Kincaid Reading Grade Level = 9.1

Additional resources related to this Data Nugget:

New research on salt marshes in Massachusetts finds they may actually thrive despite higher water levels. How is this possible? The answer has to do with sediment. Share this article with students after they complete the Data Nuggets activity, discussing research led by Brian Yellen.

3.18.16

Does sea level rise harm Saltmarsh Sparrows?

Painting of the saltmarsh sparrow

The activities are as follows:

For the last 100 years, sea levels around the globe have increased dramatically. The cause of sea level rise has been investigated and debated. Data from around the world supports the hypothesis that increasing sea levels are a result of climate change caused by the burning of fossil fuels. As we warm the Earth, the oceans get warmer and polar ice caps melt. The dramatic increase in sea level that results could seriously threaten ecosystems and the land that humans have developed along the coast.

Salt marshes are plains of grass that grow along the east coast of the United States and many coasts worldwide. Salt marshes grow right at sea level and are therefore very sensitive to sea level rise. In Boston Harbor, Massachusetts, the NOAA (National Oceanic and Atmospheric Administration) Tide Gauge has measured a 21mm rise in sea level over the last 8 years. That means every year sea level has gone up an average of 2.6mm since 2008 – more than two and a half times faster than before we started burning fossil fuels! Because sea level is going up at such a fast rate, Robert, a scientist in Boston, became concerned for the local salt marsh habitats near his home. Robert was curious about what will happen to species that depend on Boston’s Plum Island Sound salt marshes when sea levels continue to rise.

Robert preparing his team for a morning of salt marsh bird surveys.

Robert decided to look at species that are very sensitive to changes in the salt marsh. When these sensitive species are present, they indicate the marsh is healthy. When these species are no longer found in the salt marsh, there might be something wrong. The Saltmarsh Sparrow is one of the few bird species that builds its nests in the salt marsh, and is totally dependent on this habitat. Saltmarsh Sparrows rely completely on salt marshes for feeding and nesting, and therefore their numbers are expected to decline as sea levels rise and they lose nesting sites. Robert heard that scientists studying Connecticut marshes reported the nests of these sparrows have been flooded in recent years. He wanted to know if the sparrows in Massachusetts were also losing their nests because of high sea levels.

For the past two decades Robert has kept track of salt marsh breeding birds at Plum Island Sound. In his surveys since 2006, Robert counted the number of Saltmarsh Sparrows in a given area. He did these surveys in June when birds are most likely to be breeding. He used the “point count” method – standing at a center point he measured out a 100 meter circle around him. Then, for 10 minutes, he counted how many and what kinds of birds he saw or heard within and just outside the circle. Each year he set up six count circles and performed counts three times in June each year at each circle. Robert also used sea level data from Boston Harbor that he can relate to the data from his bird surveys. He predicted that sea levels would be rising in Plum Island Sound and Saltmarsh Sparrow populations would be falling over time.

Featured scientist: Robert Buchsbaum from Mass Audubon. Written by: Wendy Castagna, Daniel Gesin, Mike McCarthy, and Laura Johnson

Flesch–Kincaid Reading Grade Level = 9.5

Additional teacher resources related to this Data Nugget include:

A PDF of the 2014 overview report on the Saltmarsh Habitat and Avian Research Program (SHARP) for the east coast marshes from Maine down to Maryland, which includes Massachusetts. The report may be helpful for students as they come up with other research questions.
A blog by SHARP, covering a wide diversity of salt marsh research!
Data from the Plum Island Sound LTER project.
Data from NOAA tide gauges in Boston Harbor. This dataset expands on that found in Table 1. Students can explore long-term data for Boston Harbor, or can explore other areas for independent research.
For more Boston Harbor tide information, or to look up tides in their area, students can also explore Tideschart.

History of Data Nuggets

Because Data Nuggets originated from a partnership of teachers and scientists, they address both the needs of scientists to share their research broadly while developing their communication skills, and of teachers who need resources that address education reform and teach science in an authentic way.

Data Nuggets are designed and developed by Elizabeth Schultheis and Melissa Kjelvik from Michigan State University. They have been under development since 2011 and originated through conversations between science teachers and graduate students during the NSF GK-12 project “New GK-12: Using the STEM Dimensions of Bioenergy Sustainability to Bring Leading-edge Graduate Research to K-12 Learning Settings”. This unique opportunity for collaboration between teachers and scientists led to the creation of teacher-inspired resources. Teachers shared that they were lacking educational resources that helped their students practice working with real, messy data like that collected during classroom inquiry-based projects. Graduate students in the sciences, not surprisingly, have lots of practice working with messy data and surprising results. Through this collaboration, Data Nuggets were created to bring real data from current and ongoing research into the classroom and take students through the process of science, from the inception of ideas to the analysis and interpretation of data.

Melissa Kjelvik and teacher Connie High working together to collect scientific data.

From 2013-2015, Data Nuggets were funded with seed grants from the NSF BEACON Center Study of Evolution in Action. These funds allowed us to greatly expand Data Nuggets as a resource, with activities now being developed in response to workshops held across the BEACON consortium. The funding has also provided opportunities to collaborate with science educators at Understanding Science (UCMP), National Institute for Mathematical and Biological Synthesis (NIMBioS), and Biological Sciences Curriculum Study (BSCS) to further refine the template and to align Data Nuggets with current science standards and reform, making them easier to integrate into existing curriculum.

Data Nuggets are currently funded by a 4-year NSF DRK-12 grant, awarded to MSU and BSCS in 2015, to conduct a research study to evaluate the effectiveness of integrating Data Nuggets into science curriculum. This research will help to determine whether these short activities can increase the mathematical skills of students and their ability to think scientifically and support claims using data.

Liz Schultheis working with teachers to collect herbivory data.

We will continue to develop and revise Data Nuggets to help teachers bring sets of data from graduate student research into their classroom, and help students become comfortable working with messy data and unexpected results. Data Nuggets have gone through an iterative development process, where materials developed by scientists were used in the classroom and modified based on teacher and student experiences and feedback. We continue to present Data Nuggets at national and local education conferences where teachers and science educators can provide feedback on the structure and content of each activity. Our innovative and iterative development approach has led to a product that teachers and students find easy to work with and integrate into existing curriculum.

For more information on Data Nuggets, see our paper in the American Biology Teacher: Click here for a PDF!

BY MATH & SCIENCE CONCEPTS

Below, you will find a table of all the current Data Nuggets available. Click on the Title to open a page displaying the Data Nugget, teacher guide, student activities, grading rubric, and associated resources. The table can be sorted using the arrows located next to each column header. It can also be searched by keyword using the search bar, located to the top right of the table.

If you are looking for additional data to use with your students, search “full dataset available” to find Data Nuggets where the scientists have provided the full datasets behind the research in the activity. Email datanuggetsK16@gmail.com to get a copy of these data!

To help introduce these science and math concepts to your students, check out this set of resources.

Title	Content Level	Science Concepts / Keywords	Quantitative Concepts / Statistics	Graph Type(s)	Variable Type(s)	Data Type(s)
Dangerously bold	1	animals, animal behavior, tradeoff, fish, predation, biological significance	percent, standard error (SE), predictions	bar	categorical	summarized, Digital Data Nugget
Coral bleaching and climate change	1	climate change, coral reef, marine, mutualism, temperature, animals, algae, adaptation, evolution	ratio	bar	categorical	summarized, Digital Data Nugget
Won’t you be my urchin?	1	coral reef, herbivory, marine, sea urchin, water, animals, competition, food web	mean, models, standard error (SE), standard deviation (SD)	bar	categorical	raw
Springing forward	1 & 3	climate change, phenology, plants, temperature	mean, standard error (SE), Julian date	bar	categorical	summarized, full dataset available, Digital Data Nugget
Do urchins flip out in hot water?	1 & 3	animals, climate change, marine, heatwaves, urchins, behavior, invertebrates, environmental change	average, mean, standard error, calculation	bar	categorical, continuous	summarized, two levels available,
Do insects prefer local or foreign foods?	2	herbivory, invasive species, plants, insects, enemy release, ecology	mean, variance, standard deviation (SD), standard error (SE), confidence intervals (CI), predictions	bar	categorical	summarized, full dataset available, Digital Data Nugget
Spiders under the influence	2	animals, invertebrates, habitat, chemical pollution, aquatic, streams, scientist profile	mean, multiple variables	multiple bar	categorical	full dataset, students summarize
Do invasive species escape their enemies?	2	herbivory, invasive species, plants, insects, enemy release, ecology	mean, percent	bar	categorical	summarized
Lake Superior Rhythms	2	amplitude, aquatic, atmosphere, environmental, physics, student research, wave period, waves	cycle, sine wave, amplitude, change over time	sine wave	continuous	summarized, full dataset available
All washed up? The effect of floods on cutthroat trout	2	animals, disturbance, ecology, fish, water, stream, floods, alternative hypotheses, limnology	regression, ratio, rate, graph choice, unnecessary variables, long-term data	scatter	continuous	raw, Digital Data Nugget
Float down the Kalamazoo River	2	Kalamazoo River, water, suspended solids, dam, reservoir, limnology	mean, ratio, rate, standard deviation (SD), standard error (SE), Julian date, unnecessary variables	bar, line	categorical, continuous	summarized, Digital Data Nugget
Finding a foothold	2	animals, ecology, marine, substrate, water	frequency, proportion	bar	categorical	summarized
Is chocolate for the birds?	2	experimental design, agriculture, animals, birds, biodiversity, rainforest, succession, disturbance, transect, habitat	addition, unnecessary variables	bar	categorical	raw, full dataset available, Digital Data Nugget
Fish fights	2	animal behavior, animals, fish, mating	mean, proportion, regression	scatter	continuous	summarized, Digital Data Nugget
Marvelous mud	2	ecology, environmental, fertilization, mud, phosphorus, substrate, water, wetland, limnology	percent, regression, graph choice	scatter	continuous	summarized
Which guy should she choose?	2	animal behavior, animals, fish, mating	frequency, regression, correlation vs. causation	scatter	continuous	raw, summarized
Sexy smells	2	adaptation, animal behavior, animals, birds, mating	percent, regression, correlation vs. causation	scatter	continuous	raw, Digital Data Nugget
Shooting the poop	2	adaptation, animal behavior, animals, insects, predation, alternative hypotheses	mean, standard error (SE)	bar	categorical	raw
Invasive reeds in the salt marsh	2	disturbance, invasive species, plants, wetland, limnology, transect	mean, percent	bar	categorical	raw, summarized
A tail of two scorpions	2	animal behavior, animals, predation	addition, proportion, ratio, graph choice	bar, stacked bar, pie chart	categorical	raw, Digital Data Nugget
Green crabs: invaders in the Great Marsh	2	animals, invasive species, substrate, wetland, erosion, limnology	addition, range, map	map	categorical, spatial	raw, summarized
Guppies on the move	2	animals, aquatics, behavior, ecology, genetics, migration, movement, tropics	regression	line, scatter	categorical, continuous	raw, full dataset available
The birds of Hubbard Brook, Part I	2	animals, biodiversity, birds, climate change, succession, disturbance, ecology	count, long-term data	line, scatter	continuous	raw, full dataset available, Digital Data Nugget
Beetle battles	2	adaptation, animals, behavior, competition, evolution, insects, mating	standard error (SE)	bar	categorical	summarized
How do brain chemicals influence who wins a fight?	2	animals, behavior, competition, insects, aggression, brain chemistry, physiology	mean	bar	categorical	raw, summarized
Deadly windows	2	animals, animal behavior, birds, environmental, urban, alternative hypotheses	addition, proportion	bar	categorical	summarized
Which would a woodlouse prefer?	2	experimental design, animals, behavior, ecology, predation	count, Chi-square test, replication, sample size	bar	categorical	raw, Digital Data Nugget
Tree-killing beetles	2	animals, biodiversity, disturbance, ecology, environmental, insects, plants	mean, percent, proportion, regression	scatter	continuous	summarized
Alien life on Mars – caught in crystals?	2	astrobiology, salt, solution, Mars, extraterrestrial life, chemistry, physical science	mean, time series	line	continuous	summarized, visual, full dataset available
Beetle, it’s cold outside!	2	animals, climate change, ectotherm, insects, temperature	mean, standard error (SE), models	line	continuous	summarized, Digital Data Nugget
Can a salt marsh recover after restoration?	2	disturbance, salinity, transect, invasive species, plants, wetland, restoration, limnology	mean, percent, frequency	bar, line	continuous	summarized
Fast weeds in farmer’s fields	2	evolution, adaptation, agriculture, plants, fitness, heredity, genetics	frequency, percent, mean, replication, sample size, unnecessary variables	bar, scatter	continuous, categorical	summarized
The carbon stored in mangrove soils	2	carbon, climate change, disturbance, ecology, environmental, nutrients, greenhouse gasses, plants, transect	proportion, mean, unnecessary variables	bar	continuous, categorical	summarized
Where to find the hungry, hungry herbivores	2	herbivory, plants, insects, ecology, latitude, longitude	regression, standard deviation (SD), standard error (SE)	scatter	continuous	summarized
A window into a tree’s world	2	climate change, dendrochronology, ecology, plants, temperature	mean, relative growth, graph choice, regression, correlation vs. causation, trend line,	line, scatter	continuous, categorical	summarized
Corals in a strange place	2	adaptation, coral reef, mangrove, morphology, structure and function	visual data, count	bar, stacked bar, pie chart	continuous	summarized, full dataset available
Mangroves on the move	2	climate change, disturbance, ecology, environmental, fertilization, nitrogen, nutrients, phosphorus, plants	mean, standard error (SE)	bar	categorical, continuous	summarized
Getting to the roots of serpentine soil	2	soil, plasticity, limiting factors, plants, ecology, scientist profile	mean, range, standard deviation	bar	continuous, categorical	summarized
Little butterflies on the prairie	2	butterflies, prairie strips, prairie, agriculture, crops, farmers, animals, ecology, scientist team	Pollard Walk, transect, abundance, count, mean, long-term data, T-test	bar	continuous	summarized, full dataset available
Blinking out?	2	agriculture, insects, population, ecology, biodiversity, fireflies, scientist profile	moving window, long-term data, standardize, sampling effort, division, count, unnecessary variables	line, scatter	continuous, categorical	summarized, full dataset available, Digital Data Nugget
Buried seeds, buried treasure	2	germination, plants, seed bank, seed viability, scientist profile	long-term data, trend	scatter	continuous	raw
Mowing for monarchs, Part I	2	community science, citizen science, animals, behavior, biodiversity, community science, disturbance, ecology, plants, insects, alternative hypotheses	average, time, rate, fraction	bar	categorical	summarized, full dataset available
A difficult drought	2	agriculture, biofuels, climate change, plants, carbon, fermentation, ethanol, chemistry	mean, range, variability, replication, sample size	bar	continuous, categorical	summarized, full dataset available
Farms in the fight against climate change	2	Carbon, Soil, LTER, climate change	average, standard deviation, percent, bar plot	bar	categorical, continuous	summarized, raw
Mowing for monarchs, Part II	2	community science, citizen science, animals, behavior, biodiversity, community science, disturbance, ecology, plants, insects, predation, alternative hypotheses	average, time, rate, fraction	bar	categorical	summarized, full dataset available
Does more rain make healthy bison babies?	2	animals, ecology, keystone species, plants, prairie, precipitation	mean, time, regression, long-term data, unnecessary variables	line, scatter	continuous	summarized, full dataset available
Benthic buddies	2	adaptation, animals, arctic, biodiversity, ecology, environmental, invertebrates, lagoons, marine	mean	bar	categorical	summarized
Did you hear that? Inside the world of fruit fly mating songs	2	animals, insect, process of science, reproducibility, communication, volume, social, behavior	calculations, index, standard deviation, average, replicate	bar	categorical, continuous	summarized
A burning question	2	biodiversity, canopy, ecology, fire ecology, forest, human impact, keystone species, land management, natural resources	average, time	bar	categorical, continuous	summarized
Are plants more toxic in the tropics?	3	herbivory, diversity, plants, insects, ecology, adaptation, chemistry	standard deviation (SD), standard error (SE), index, formula	bar	categorical	summarized
Does a partner in crime make it easier to invade?	3	legume, plants, mutualism, rhizobia, invasive species, soil, scientist profile	mean	bar	categorical	summarized
Fair traders or freeloaders?	3	evolution, legume, plants, mutualism, rhizobia, nitrogen, fertilization	mean, standard error (SE)	bar	categorical	summarized
Fertilizing biofuels may cause release of greenhouse gasses	3	agriculture, biofuels, climate change, fertilization, greenhouse gases, nitrogen, plants	regression	scatter	continuous	summarized, full dataset available, Digital Data Nugget
The ground has gas!	3	climate change, temperature, greenouse gases, nitrogen, plants	regression	scatter	continuous	raw, summarized, full dataset available
Growing energy: comparing biofuel crop biomass	3	agriculture, biofuels, climate change, fertilization, plants, carbon	mean, standard error (SE)	bar	categorical	summarized
Microbes facing tough times	3	drought, enzymes, microbes, mutualist, agriculture, climate change, crops	mean, standard deviation, negative values	bar	continuous	summarized
How the cricket lost its song, Part I	3	adaptation, animal behavior, animals, rapid evolution, mating, parasitism, scientist profile	percent	bar	categorical	raw, summarized, Digital Data Nugget
The mystery of Plum Island Marsh	3	fertilization, fish, food web, marine, mollusk, water, wetland, limnology	mean	bar	categorical	raw
Invasion meltdown	3	climate change, ecology, invasive species, plants, temperature	mean, range, replication, sample size	bar	categorical	summarized, full dataset available
Is your salt marsh in the zone?	3	climate change, ecology, plants, sea level rise, substrate, wetland, limnology	mean	bar	categorical	raw
Lizards, iguanas, and snakes! Oh my!	3	animals, biodiversity, disturbance, restoration, urban, transect	count, addition	bar	categorical	raw
What do trees know about rain?	3	climate change, dendrochronology, ecology, plants, precipitation, temperature, water	mean, formula, equation, addition, multiplication	line	continuous	raw, full dataset available
CSI: Crime Solving Insects	3	animals, insects, parasitism	weighted mean	bar	categorical	raw, Digital Data Nugget
Does sea level rise harm saltmarsh sparrows?	3	animals, birds, sea level rise, climate change, disturbance, ecology, wetland, limnology	mean, standard deviation (SD)	line	continuous	summarized
Keeping up with the sea level	3	climate change, disturbance, ecology, sea level rise, plants, substrate, wetland, limnology	formula, equation, rate	line, scatter	continuous, categorical	raw
The birds of Hubbard Brook, Part II	3	animals, biodiversity, birds, climate change, succession, disturbance, habitat, ecology	count, long-term data	line, scatter	continuous, categorical	raw, full dataset available, Digital Data Nugget
How the cricket lost its song, Part II	3	adaptation, animal behavior, animals, rapid evolution, mating, parasitism, scientist profile	mean	bar	categorical	raw, summarized. Digital Data Nugget
Feral chickens fly the coop	3	adaptation, animals, behavior, birds, ecology, evolution, invasive species, mating, heredity, genetics	proportion, percent	bar	categorical	raw, summarized
Raising Nemo: Parental care in the clown anemonefish	3	animals, behavior, coral reef, ecology, fish, marine, mating, tradeoff, plasticity, scientist profile	mean, standard error (SE)	bar	categorical	raw
When a species can’t stand the heat	3	animals, climate change, disturbance, ecology, environmental, mating, temperature, sex ratio	addition, percent, ratio, regression	scatter	continuous	raw, full dataset available, Digital Data Nugget
Are you my species?	3	adaptation, animals, behavior, biodiversity, competition, evolution, fish, mating	formula, equation, addition, subtraction, division, regression	scatter	continuous	raw, Digital Data Nugget
Marsh makeover	3	bodiversity, disturbance, ecology, greenhouse gases, mud, plants, restoration, wetland, limnology	standard error (SE)	bar, line	categorical	raw, summarized
To bee or not to bee aggressive	3	animals, behavior, genes, insects, tradeoff, plasticity, aggression	mean, effect size, percent change, range	bar	categorical	summarized, full dataset available, Digital Data Nugget
Why are butterfly wings colorful?	3	adaptation, animals, insects, models, predation, alternative hypotheses	fraction, proportion, probability	bar	categorical	summarized, Digital Data Nugget
City parks: wildlife islands in a sea of cement	3	animals, biodiversity, ecology, urban, island biogeography, parks, camera trap	Shannon Wiener Index, formula, equation, sum, proportion, regression	scatter	continuous	summarized, full dataset available, Digital Data Nugget
Is it better to be bigger?	3	adaptation, animals, evolution, predation, natural selection	mean, percent, rate, regression	scatter	continuous	summarized, Digital Data Nugget
Is it dangerous to be a showoff?	3	adaptation, animals, evolution, predation, tradeoff, natural selection	percent, rate, regression	scatter	continuous, categorical	summarized
What big teeth you have! Sexual selection in rhesus macaques	3	animals, evolution, sexual selection, sexual dimorphism, anatomy, form and function, primate, scientist profile	mean, standard deviation (SD)	bar	continuous, categorical	raw, Digital Data Nugget
Bringing back the Trumpeter Swan	3	animals, biodiversity, birds, ecology, environmental, restoration	mean, long-term data, count	line	continuous, categorical	raw, full dataset available, Digital Data Nugget
Are forests helping in the fight against climate change?	3	climate change, carbon, ecology, greenhouse gasses, photosynthesis, plants, decomposition, respiration	regression, long-term data	scatter	continuous	raw
Can biochar improve crop yields?	3	agriculture, environmental, fertilization, plants, soil, water, biochar, carbon	percent, mean, standard deviation (SD), yield, replication, sample size, randomization	bar	continuous, categorical	summarized
Hold on for your life! Part I	3	adaptation, animals, disturbance, evolution, natural selection, genetic drift, hurricane, biological significance, alternative hypotheses	argumentation, mean, standard error (SE)	bar	continuous, categorical	summarized
Hold on for your life! Part II	3	adaptation, animals, disturbance, evolution, natural selection, genetic drift, hurricane	argumentation, visual data		visual	raw, photo, video
Testing the tolerance of invasive plants	3	ecology, herbivory, invasive species, plants, tolerance	statistical interaction, mean, standard error (SE)	bar	categorical	summarized, full dataset available
Picky eaters: Dissecting poo to examine moose diets	3	animal behavior, animals, ecology, foraging, herbivory, parks, predator-prey	1:1 line, proportion, mean, unnecessary variables	scatter	continuous, categorical	summarized, full dataset available
Candid camera: capturing the secret lives of carnivores	3	animals, biodiversity, carnivores, ecology, island biogeography, richness, camera trap, parks	regression	map, scatter	continuous	summarized, Digital Data Nugget
Crunchy or squishy? How El Niño events change zooplankton	3	algae, animals, marine, El Niño	outlier, correlation vs. causation, unnecessary variables	line, scatter	continuous	raw, Digital Data Nugget
Streams as sensors: Arctic watersheds as indicators of change	3	climate change, ecology, environmental, carbon, nitrogen, permafrost, limnology	unnecessary variables, regression, long-term data	scatter	continuous	summarized
The end of winter as we’ve known it?	3	climate change, ice cover	Julian date, mean, regression, messiness, variability	scatter	continuous	summarized, full dataset available, Digital Data Nugget
Working to reduce the plastics problem	3	plastics, synthetic materials, chemistry, biodegradable, elastomer, polymer, monomer, stress, strain, physical science	percent, ratio	line	continuous	summarized
Limit by limit: Nutrients control algal growth in Arctic streams	3	nitrogen, nutrients, phosphorus, nutrient limitation, law of the minimum, Arctic, limnology	response ratio, graph choice, standard deviation (SD)	bar	categorical	summarized
To reflect, or not to reflect, that is the question	3	albedo, arctic, climate change, environmental, ice, temperature, water	equation, unnecessary variables, regression	line, scatter	continuous	summarized
How milkweed plants defend against monarch butterflies	3	herbivory, evolution, coevolution, plants, insects, ecology, scientist profile	mean, regression, best fit line, trend line, multiple dependent variables, messiness, outlier	line, scatter	continuous	summarized
Purring crickets: The evolution of a new cricket song	3	adaptation, animal behavior, animals, rapid evolution, mating, parasitism, scientist profile	mean, percent, Chi-square test	bar	categorical	raw, Digital Data Nugget
Round goby, skinny goby	3	local adaptation, animals, biodiversity, rapid evolution, fish, Great Lakes, habitat, invasive species, Kalamazoo River	mean, standard error, replication, sample size	bar	categorical	summarized, full dataset available
David vs. Goliath	3	aggression, animals, behavior, brain chemistry, competition, insects, physiology, biological significance	frequency, proportion, percent, unnecessary variables	bar	categorical	raw, summarized
Size matters - and so does how you carry it!	3	adaptation, animals, evolution, insects, sexual selection, tradeoffs	residuals, trend, multiple graphs, standardize	scatter, line	continuous	raw, summarized, full dataset available
Do you feel the urban heat?	3	urban, climate change, extreme heat, environmental justice, human impacts, socioeconomic, sensors	maximum, minimum, averages, time, baseline	multiple line	continuous, categorical	summarized
Ant wars!	3	aggression, animals, behavior, competition, insects	density, ratio, percent, regression, count	bar, line, scatter	continuous	raw, summarized
Salty sediments? What bacteria have to say about chloride pollution	3	bacteria, chemistry, disturbance, environmental, microbes, pollution, salt, urban, water, habitat, time, toxicity	mean, concentration	bar	categorical	summarized
Going underground to investigate carbon locked in soils	3	climate change, ecology, environmental, greenhouse gasses, soil carbon, microbes, chemistry	mean, standard deviation (SD), regression, best fit line, trend line, correlation vs. causation	line, scatter	continuous	summarized
Nitrate: Good for plants, bad for drinking water	3	agriculture, environmental, fertilization, nitrogen, soil, water, plants, human health	mean, time, date, Julian date, concentration	line, scatter	continuous, categorical	summarized, full dataset available
Trees and the city	3	biodiversity, ecology, environmental justice, social demographics, urban	spatial data analysis, percent, binned data, average, median, histogram	multiple scatter, spatial map	continuous	spatial, summarized, full dataset available
Collaborative cropping: Can plants help each other grow?	3	agriculture, environmental, plants, crops	replicates, correlation vs. causation, regression, trend	multiple scatter	continuous	raw
The sound of seagrass	3	acoustics, sound, photosynthesis, marine, productivity, decibels, physics	average, mean, standard deviation, trend, time	multiple scatter, line	continuous	summarized
Which tundra plants will win the climate change race?	3	climate change, nutrients, long-term data, competition, plants, ecology	mean, trend, time, series, control, long-term data	line	continuous	summarized
The prairie burns with desire	3	ecology, prairie, plants, fire ecology, human impact, reproduction, land management	trend, time, multiple plots, multiple variables, long-term data, proportion, average	scatter, line	continuous	summarized, full dataset available
Seagrass survival in a super salty lagoon	3	climate change, ecology, environmental, long-term, marine, plants, salinity	double y-axis, trend, time, multiple variables	scatter	continuous	summarized
Sink or source? How grazing geese impact the carbon cycle	3	carbon cycle, Arctic, wetlands, primary production, photosynthesis, respiration, climate change, birds, ecosystem	equation, calculation, subtraction, negative values, source, sink	bar	categorical, continuous	summarized
Poop, poop, goose!	3	wetlands, Arctic, carbon cycle, climate change, disturbance, ecology, environmental, greenhouse gasses, birds	mean, standard deviation (SD), flux	bar	categorical	summarized
Too hot to help? Friendship in a changing climate	3	mutualism, algae, coral, genotype, photosynthesis, respiration, climate change	calculations, negative values, net, mean, average, standard error	bar	categorical, continuous	summarized
Does the heat turn caterpillars into cannibals?	3	animal behavior, insect, virus, disease ecology, temperature, cannibalism, caterpillar	calculation, percents	bar	categorical, continuous	summarized
A plant breeder’s quest to improve perennial grain	4	genetics, artificial selection, DNA, selective breeding, phenotype, genotype, nucleotides, sequencing	calculations, average, predictions, standard error, standard deviation,	bar	continuous, categorical	supplemental activity available,
Cheaters in nature – when is a mutualism not a mutualism?	4	evolution, legume, plants, mutualism, parasitism, rhizobia, nitrogen, fertilization	mean, standard error (SE)	bar	categorical	summarized
Dangerous aquatic prey: can predators adapt to toxic algae?	4	adaptation, algae, evolution, marine, predation	mean	bar	categorical	summarized
Salmon in hot water	4	adaptation, animals, climate change, evolution, fish, genes, genome, temperature, DNA, heredity, genetics, QTL	mean	line	continuous	summarized
Urbanization and estuary eutrophication	4	algae, eutrophication, fertilization, marine, nitrogen, phosphorus, wetland, urban, photosynthesis, respiration, limnology	mean, standard error (SE), subtraction, model	bar	categorical	raw
How to escape a predator	4	adaptation, animal behavior, animals, predation, physiology	mean, standard error (SE)	bar	categorical	raw, summarized
The flight of the stalk-eyed fly	4	physics, moment of intertia, adaptation, animals, flight, physiology	mean, standard error (SE), formula, equation, multiplication		continuous	summarized
Make way for mummichogs	4	animals, biodiversity, disturbance, fish, restoration, wetland, limnology	mean	bar, line	continuous	raw, summarized
The Arctic is melting – so what?	4	climate change, marine, temperature, water, weather, ice, Arctic, albedo	percent, models	diagram	categorical, modeled data	summarized
Gene expression in stem cells	4	gene expression, genes, stem cells, DNA, genetics, human health	mean	bar	categorical	summarized, Digital Data Nugget
Bon Appétit! Why do male crickets feed females during courtship?	4	adaptation, animals, behavior, competition, insects, mating, feeding, alternative hypotheses, scientist profile	count, proportion, regression, multiple regression, unnecessary variables	scatter	continuous	raw, Digital Data Nugget
Winter is coming! Can you handle the freeze?	4	ecology, evolution, genes, plants, local adaptation, QTL	percent, standard deviation (SD), standard error (SE)	bar, line	categorical	raw, summarized
Finding Mr. Right	4	animals, animal behavior, biodiversity, birds, evolution, genes, mating, local adaptation	mean	bar	categorical	raw
Why so blue? The determinants of color pattern in killifish, Part I	4	adaptation, animals, biodiversity, evolution, fish, genes, mating, heredity, genetics, close reading activity	mean, standard deviation (SD), standarad error (SE)	bar	categorical	raw, summarized
Why so blue? The determinants of color pattern in killifish, Part II	4	adaptation, animals, biodiversity, evolution, fish, genes, mating, heredity, genetics	mean, standard deviation (SD), standarad error (SE)	bar	categorical	raw, summarized
Sticky situations: big and small animals with sticky feet	4	adaptation, animals, biomimicry, chemistry, physics, scale	mean, ratio, multiplication, formula, equation, surface area, mass, volume	scatter - logarithmic axes	continuous	summarized
When whale I sea you again?	4	climate change, marine, temperature, water, whales, DNA, PCR, sex ratio	fraction, percent, ratio	line, stacked bar	continuous, categorical	raw, Digital Data Nugget
The case of the collapsing soil	4	climate change, carbon, ecology, plants, phosphorus, sea level rise, respiration, substrate, wetland, limnology	regression, concentration	scatter	continuous	raw, Digital Data Nugget
Clique wars: social conflict in daffodil cichlids	4	animal behavior, animals, competition, fish	count, standard deviation (SD), standarad error (SE)	bar	categorical	summarized, Digital Data Nugget
Fishy origins	4	community science, citizen science, DNA, evolution, fish, PCR, marine, microsatellites	percent, proportion, addition, division	bar, stacked bar	continuous, categorical	raw
Fertilizer and fire change microbes in prairie soil	4	biodiversity, diversity, grassland, microbes, plants, prairie, soil	unnecessary variables, Shannon Wiener Index, mean	bar	continuous, categorical	summarized
Breathing in, Part I	4	photosynthesis, carbon accumulation, carbon sequestration, climate change, forest, habitat	mean, confidence, global database	bar	continuous, categorical	summarized, full dataset available
Breathing in, Part 2	4	climate change, photosynthesis, respiration, carbon, climate model	precision, percent, model prediction, mean, calculation, equation	bar	continuous, categorical	summarized, full dataset available
Stop that oxidation! What fruit flies teach us about human health	4	insects, model species, cell biology, genetics, cellular processes, oxidation, genetics, scientist profile	mean	bar	continuous, categorical	raw, summarized
Love that dirty water	4	environmental, urban, water, GIS, landscapes, impervious surfaces, ecosystem services, land acknowledgement, human health	model, web-tool, simulation, percent change, calculation, map	bar, line, map	categorical, continuous	summarized
Trees and bushes, home sweet home for warblers	4	animals, biodiversity, disturbance, ecology, birds, succession, transect, habitat	regression, best fit line, trend line, percent	scatter	continuous	summarized
Changing climates in the Rocky Mountains	4	citizen science, climate change, community science, ecology, environmental, plants, precipitation, temperature	mean, trend, time	line, double y-axis	continuous, categorical	summarized, photo
Surviving the flood	4	disturbance, urban, stream, floods, photosynthesis, respiration, stormwater	reference line, percent, negative values, additional variables, difference, unnecessary variables, outlier	scatter, line	continuous	raw, summarized
Eavesdropping on the ocean	4	acoustic ecology, physics, whales technology, mammals, marine biology, renewable energy, population, human impact	proportions, calculation, detections	scatter, bar	categorical, continuous	summarized, full dataset available
Reconstructing the behaviour of ancient animals	4	anatomy, animals, behavior, form and function, fossils, nocturnal, paleobiology, primate	mean, average, range, maximum, minimum, box and whisker plot	bar, box and whisker plot	categorical, continuous	summarized

11.3.15

Lizards, iguanas, and snakes! Oh my!

The Common Side-blotched Lizard

The activities are as follows:

Throughout history people have settled mainly along rivers and streams. Easy access to water provides resources to support many people living in one area. In the United States today, people have settled along 70% of rivers.

Today, rivers are very different from what they were like before people settled near them. The land surrounding these rivers, called riparian habitats, has been transformed into land for farming, businesses, or housing for people. This urbanization has caused the loss of green spaces that provide valuable services, such as water filtration, species diversity, and a connection to nature for people living in cities. Today, people are trying to restore green spaces along the river to bring back these services. Restoration of disturbed riparian habitats will hopefully bring back native species and all the other benefits these habitats provide.

Scientist Mélanie searching for reptiles in the Central Arizona-Phoenix LTER.

Scientists Heather and Mélanie are researchers with the Central Arizona-Phoenix Long-Term Ecological Research (CAP LTER) project. They want to know how restoration will affect animals living near rivers. They are particularly interested in reptiles, such as lizards. Reptiles play important roles in riparian habitats. Reptiles help energy flow and nutrient cycling. This means that if reptiles live in restored riparian habitats, they could increase the long-term health of those habitats. Reptiles can also offer clues about the condition of an ecosystem. Areas where reptiles are found are usually in better condition than areas where reptiles do not live.

Heather and Mélanie wanted to look at how disturbances in riparian habitats affected reptiles. They wanted to know if reptile abundance (number of individuals) and diversity (number of species) would be different in areas that were more developed. Some reptile species may be sensitive to urbanization, but if these habitats are restored their diversity and abundance might increase or return to pre-urbanization levels. The scientists collected data along the Salt River in Arizona. They had three sites: 1) a non-urban site, 2) an urban disturbed site, and 3) an urban rehabilitated site. They counted reptiles that they saw during a survey. At each site, they searched 21 plots that were 10 meters wide and 20 meters long. The sites were located along 7 transects, or paths measured out to collect data. Transects were laid out along the riparian habitat of the stream and there were 3 plots per transect. Each plot was surveyed 5 times. They searched for animals on the ground, under rocks, and in trees and shrubs.

Featured scientists: Heather Bateman and Mélanie Banville from Arizona State University. Written by Monica Elser from Arizona State University.

Flesch–Kincaid Reading Grade Level = 9.8

Check out this video of Heather and her lab out in the field collecting lizards:

Virtual field trip to the Salt River biodiversity project:

Additional resources related to this Data Nugget:

For more background on the importance of biodiversity, students can eat this article in The Guardian – What is biodiversity and why does it matter to us?

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10.21.15

Is your salt marsh in the zone?

Scientist James collecting plants in a Massachusetts marsh, part of the Plum Island Ecosystems Long Term Ecological Research site

The activities are as follows:

Tides are the rise and fall of ocean water levels, and happen every day like clockwork. Gravity from the moon and sun drive the tides. There is a high tide and a low tide, and the average height of the tide is called the mean sea level. The mean sea level changes seasonally due to the warming and cooling of the ocean throughout the year. It also changes annually due to a long-term trend of ocean warming and the melting of glaciers. Scientific evidence shows that climate change is causing the sea level to rise faster now than it has in the past. As the climate continues to warm, it is predicted that the sea level will continue to rise.

Salt marshes are wetlands with plains of grass that grow along much of the ocean’s coast worldwide. These marshes are important habitats for many plants and animals, and protect our shores from erosion during storms. They grow between mean sea level and the level of high tide. Marshes flood during high tide and are exposed to the air during low tide. The health of a salt marsh is determined by where it sits relative to the tide (the “zone”). A healthy marsh is flooded only part of the time. Too much flooding and too little flooding are unhealthy. Because they are so important, scientists want to know if salt marshes will keep up with sea level rise caused by climate change.

A picture of James’ “marsh organ” which holds plants at different elevations relative to mean sea level. He gave it that name because it resembles organ pipes!

In the 1980s, scientist James began measuring the growth of marsh grasses. He was surprised to find that there was a long-term trend of increasing grass growth over the years. James wanted to know if grasses could continue to keep up with rising sea levels. If he could experimentally manipulate the height of the grasses, relative to mean sea level, he might be able to figure out how grasses will do when sea levels are higher. To test this, James invented a way to experimentally grow a marsh at different elevations relative to mean sea level. He built a device he called the “marsh organ”. This device is made of tubes that stand at different elevations and are filled with marsh mud and planted with marsh grasses. He measured the growth of the grass in each of the pipes. If grasses will continue to grow taller in the future with higher water levels, then plants growing in pipes at lower elevations should grow more than plants growing in pipes with higher elevations.

Featured scientist: James Morris from the University of South Carolina

Additional teacher resource related to this Data Nugget: Jim has created an interactive salt marsh model called the “marsh equilibrium model”. This online tool allows you to plug in different marsh levels to explore potential impacts to the salt marsh. To explore this tool click here.

To read more about Jim’s research on “tipping points” beyond which sediment accumulation fails to keep up with rising sea level and the marshes drown, click here.

There are two publications related to the data included in this activity:

Morris, J.T., Sundberg, K., and Hopkinson, C.S. 2013. Salt marsh primary production and its responses to relative sea level and nutrients in estuaries at Plum Island, Massachusetts, and North Inlet, South Carolina, USA. Oceanography 26:78-84.
Morris, J.T., P.V. Sundareshwar, C.T. Nietch, B. Kjerfve, D.R. Cahoon. 2002. Responses of coastal wetlands to rising sea level. Ecology 83:2869-2877.

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10.19.15

Green crabs: invaders in the Great Marsh

Scientist Alyssa holding a non-native green crab, introduced from Europe to the American Atlantic Coast. This crab causes many problems in its new range, including the loss of native eelgrass.

The activities are as follows:

Marshes, areas along the coast that flood with each tide, are incredibly important habitats. They act as homes to large number of species, protect the coast from erosion during storms, and act as a filter for nutrients and pollution. Many species are unique to these habitats and provide crucial support to the marsh. For example, native eelgrass, a type of plant, minimizes erosion by holding sediments in place with their roots.

In an effort to help protect and restore marshes, we must understand current-day issues that are affecting their health. The introduction of non-native species, species that are not originally from this ecosystem, into a marsh may disrupt the marsh ecosystem and threaten the survival of native species. One species that has recently caused a lot of trouble is the European green crab. This crab species was accidentally carried to the Atlantic coast back in the early 1800s from Europe. Since then, they have become extremely invasive and their numbers have exploded! Compared to native crabs, the green crab digs a lot when it searches for food and shelter. This digging uproots eelgrass and causes its population numbers to fall. In many spots where green crabs have been introduced, marshes are now bare and no more grass can grow.

Non-native green crabs caught in trap that has been underwater for 25 hours

The Great Marsh is one of the coastal habitats affected by invasive green crabs. Located on the North Shore of Massachusetts, the Great Marsh is known for being the longest continuous stretch of salt marsh in all of New England. Alyssa is a restoration ecologist who is very concerned with the conservation of the Great Marsh and other important coastal ecosystems. She and other scientists are trying to maintain native species while also reducing the effects of non-native species.

A major goal for Alyssa is to restore populations of a native eelgrass. Eelgrass does more than just prevent erosion. It also improves water quality, provides food and habitat for native animal species, and acts as an indicator of marsh health. If green crabs are responsible for the loss of eelgrass from the marsh, then restorations where eelgrass is planted back into the marsh should be more successful where green crab numbers are low. Alyssa has been measuring green crab populations in different areas by laying out green crab traps for 24 hours. Alyssa has set these traps around Essex Bay, an area within the Great Marsh. She recorded the total number of green crabs caught at each location (as well as their body size and sex).

Native eelgrass growing in Essex Bay, an area within the Great Marsh

Featured scientist: Alyssa Novak, Center for Coastal Studies/Boston University. Written by: Hanna Morgensen

Flesch–Kincaid Reading Grade Level = 8.8

8.24.15

Urbanization and estuary eutrophication

Charles Hopkinson out taking dissolved O2 measurements.

The activities are as follows:

An estuary is a habitat formed where a freshwater river or stream meets a saltwater ocean. Many estuaries can be found along the Atlantic coast of North America. Reeds and grasses are the dominant type of plant in estuaries because they are able to tolerate and grow in the salty water. Where these reeds and grasses grow they form a special habitat called a salt marsh. Salt marshes are important because they filter polluted water and buffer the land from storms. Salt marshes are the habitat for many different kinds of plants, fish, shellfish, and birds.

Hap Garritt removing an oxygen logger from Middle Road Bridge in winter.

Scientists are worried because some salt marshes are in trouble! Runoff from rain washes nutrients, usually from lawn fertilizers and agriculture, from land and carries them to estuaries. When excess nutrients, such as nitrogen or phosphorus, enter an ecosystem the natural balance is disrupted. The ecosystem becomes more productive, called eutrophication. Eutrophication can cause major problems for estuaries and other habitats.

With more nutrients in the ecosystem, the growth of plants and algae explodes. During the day, algae photosynthesize and release O₂ as a byproduct. However, excess nutrients cause these same algae grow densely near the surface of the water, decreasing the light available to plants growing below the water on the soil surface. Without light, the plants die and are broken down by decomposers. Decomposers, such as bacteria, use a lot of O₂because they respire as they break down plant material. Because there is so much dead plant material for decomposers, they use up most of the O₂ dissolved in the water. Eventually there is not enough O₂for aquatic animals, such as fish and shellfish, and they begin to die-off as well.

Two features can be used to identify whether eutrophication is occurring. The first feature is low levels of dissolved O₂ in the water. The second feature is when there are large changes in the amount of dissolved O₂ from dawn to dusk. Remember, during the day when it’s sunny, photosynthesis converts CO₂, water, and light into glucose and O₂. Decomposition reverses the process, using glucose and O₂ and producing CO₂ and water. This means that when the sun is down at night, O₂ is not being added to the water from photosynthesis. However, O₂ is still being used for decomposition and respiration by animals and plants at night.

The scientists focused on two locations in the Plum Island Estuary and measured dissolved O₂ levels, or the amount of O₂in the water. They looked at how the levels of O₂ changed throughout the day and night. They predicted that the upper part of the estuary would show the two features of eutrophication because it is located near an urban area. They also predicted the lower part of the estuary would not be affected by eutrophication because it was farther from urban areas.

A view of the Plum Island estuary

Featured scientists: Charles Hopkinson from University of Georgia and Hap Garritt from the Marine Biological Laboratory Ecosystems Center

Flesch–Kincaid Reading Grade Level = 9.6