Sean Caroll: An Ecology Lesson

Nautilus:

“Why is the planet green? Why don’t the animals eat all of the food? And what happens when certain animals are removed from a place? These questions led to the discovery that, just as there are molecular rules that regulate the numbers of different kinds of molecules and cells in the body, there are ecological rules that regulate the numbers and kinds of animals and plants in a given place. And these rules may have as much or more to do with our future welfare than all the molecular rules we may ever discover...

One major school of thought was that population size was controlled by physical conditions such as the weather. Smith, Hairston, and Slobodkin (hereafter dubbed “HSS”) all doubted this idea because, if true, it meant that population sizes fluctuated randomly with the weather. Instead, the trio was convinced that biological processes must control the abundance of species in nature, at least to some degree.

HSS pictured the food chain as subdivided into different levels according to the food each consumed (known as trophic levels). At the bottom were the decomposers that degrade organic debris; above them were the producers, the plants that relied on sunlight, rain, and soil nutrients; the next level were the consumers, the herbivores that ate plants; and above them the predators that ate the herbivores.

The ecological community generally accepted that each level limited the next higher level; that is, populations were positively regulated from the “bottom up.” But Smith and his lunch buddies pondered the observation that seemed at odds with this view: The terrestrial world is green. They knew that herbivores generally do not completely consume all of the vegetation available. Indeed, most plant leaves only show signs of being partially eaten. To HSS, that meant that herbivores were not food-limited, and that something else was limiting herbivore populations. That something, they believed, were predators, negatively regulating herbivore populations from the “top-down” in the food chain. While predator-prey relationships had long been studied by ecologists, it was generally thought that the availability of prey regulated predator numbers and not vice-versa. The proposal that predators as a whole acted to regulate prey populations was a radical twist...

Indeed, trophic cascades have been discovered across the globe, where keystone predators such as wolves, lions, sharks, coyotes, starfish, and spiders shape communities. And because of their newly appreciated regulatory roles, the loss of large predators over the past century has Estes, Paine, and many other biologists deeply concerned.”

Luke Runyon: Causes of the Monarch Butterfly Decline→

NPR:

“Monarch butterflies are disappearing. Populations of these distinctive black and orange migratory insects have been in precipitous decline for the past 20 years, but scientists aren’t exactly sure what’s causing them to vanish.

So far, potential culprits include disease, climate change, drought and deforestation. Everyone from loggers to suburban developers has been implicated. But much of the blame has been placed on farmers and the pesticides they rely on — pesticides that have reduced the milkweed that monarch caterpillars feast on. Now, however, scientists say that may not be the full story.

Every spring, hundreds of thousands of monarchs sweep across the Great Plains from Mexico to Canada, and then back again in the fall. It’s an amazing journey, one that takes place over multiple generations for the butterflies. The insects breed while traveling north, expending four generations to make it to Canada. The final generation then flies all the way back to Mexico to spend the winter there.

Monarch populations are measured in hectares (roughly 2 1/2 acres). Surveys of their wintering habitats in the central mountains of Mexico show dense populations of monarchs at an average of more than nine hectares during the winters from 1995 to 2002. In 2014, monarchs took up less than one hectare.”

Global Warming Visual→

Climate Lab:

“The animated spiral presents global temperature change in a visually appealing and straightforward way. The pace of change is immediately obvious, especially over the past few decades. The relationship between current global temperatures and the internationally discussed target limits are also clear without much complex interpretation needed.”

Click this link to go to the animated data graphic. An interesting way to present a lot of data!

Samantha Oliver: Altered Nutrient Flows into Lakes→

UW-Madison Center of Limnology:

“Humans have drastically changed the distribution of nutrients (nitrogen and phosphorus) across the landscape through urbanization, food production and burning fossil fuels. This has come at a cost to water quality; excess nutrients are transported to surface waters where they can fuel toxic algal blooms, foul drinking water and disrupt the ecosystem. We’ve made progress on point source pollution like sewage discharge since the Clean Water Act was established in 1972. But diffuse nutrient sources like runoff from agricultural areas are difficult to manage and still plague surface waters.”

Jake Vander Zanden: Lake Dead Zones→

Reporting from New Zealand:

“UW-Madison’s Limnology Center: Earlier this year, Jake Vander Zanden rented his house out in Madison, packed his things, and headed with his family for a sabbatical in New Zealand. Under the auspices of a Fulbright scholarship, Jake is at the University of Waikato, studying ‘dead zones’ in lakes, where pollution reduces oxygen making it impossible for parts of lakes to support life.

Tell us about your research here in New Zealand
I’m looking at the phenomenon of lake ‘dead zones’. Lakes that in the past had a lot of oxygen in the bottom waters can lose that oxygen due to nutrient pollution – often from human activity – then they become an environment that can’t support life. You lose a lot of the value that would come from a lake, such as fisheries, when you have dead zones.

It seems like once you create dead zones they are difficult to turn back. Even if you remove nutrients and improve conditions, the healthy ecosystem never returns. That’s really worrisome because it is so difficult to fix the problem. Another consideration is that when you create a dead zone, the plant nutrient phosphorus is released from the lake sediments, which further contributes to the pollution problem.”

Julienne Isaacs: The Benefits and Limits of Buffers→

Manitoba Co-operator:

“Sandi Riemersma, an environmental biologist with Palliser Environmental Services, says the effectiveness of buffers depends on several factors, including the slope of land, soil characteristics, buffer width, vegetation, season and management.

“A riparian buffer strip is a good tool to reduce sediment transport and often can reduce particulate phosphorus mobility,” she says. “But buffers are not effective in winter and early spring when vegetation is dormant, soils are frozen and microbial activity is low or absent,” she says.

Riemersma emphasizes nutrient application management as an essential aspect of protecting waterways from nutrient run-off. In addition, she says permanent cover should be maintained near waterways, steep slopes and on erodible and saline soils. “Riparian buffers help to maintain stable stream banks, thereby reducing soil erosion and associated sediment and nutrient transport in waterways,” she says.”

Minnehaha Watershed District: Zebra Mussels Improve Water Clarity in Lake Minnetonka→

“Zebra mussels have caused significant changes in Lake Minnetonka’s water quality, according to findings of a study by Minnehaha Creek Watershed District (MCWD). The District has been monitoring the lake’s zebra mussel population since they were first detected there in 2010. Five years into the study, which was developed in partnership with Blue Water Science, MCWD released its findings on Thursdsay, April 21 at its AIS Spotlight, a gathering of community leaders at Minnetonka Community Center.

The District has discovered the biggest water quality changes are occurring among bays with the highest number of zebra mussels. In Wayzata Bay, which the population topped out at an estimated 200,000 zebra mussels per square meter in 2014, there has been an increase in water clarity and a decrease in algae (Chlorophyll) and Phosphorus. Those changes are not as prevalent in bays with lower zebra mussel populations. In Halsted Bay, which has 28 zebra mussels per square meter, there has been little change in water clarity, Chlorophyll and Phosphorus.”

One suspects that some bays with improved water clarity may see an increase in aquatic plant habitat.

Lee Bergquist: Little Plover River Groundwater Study→

Journal Sentinel:

“A long-awaited study that examines how irrigation is affecting the closely watched Little Plover River in central Wisconsin could help prevent the river from running dry again.

The results of the state-funded research also may provide clues on how large-scale groundwater withdrawals are affecting streams, rivers and lakes elsewhere, according to scientists.

Groundwater issues have become increasingly contentious in Wisconsin, especially in the 1.75 million-acre Central Sands region — home to a large potato and vegetable growing industry. The region relies on more than 3,000 high-capacity wells to grow crops.

The Little Plover, a Class 1 trout stream, flows for about 6 miles near Stevens Point before it enters the Wisconsin River. But more than its reputation for fishing, the river is infamously known for stretches that run dry, as they did in 2005 and 2009.”

Good groundwater science was done years ago by Dr. Kraft, who was quoted in this article. However, farmers and civic leaders apparently did not want to hear about how farm irrigation was the main reason for lower river flows. So the science and the predictions are now better and yet some farmers and civic leaders apparently still will not be convinced. When you start with a given pre-set belief or dogma and then search for any argument to rationalize, defend or justify the overexploiting of a pubic resource, then you are corrupt and your actions self-servicing. 

Wisconsin Public Radio's Route 51 broadcast a program discussing the newly released scientific study of the effects of high capacity wells on groundwater and the Little Plover River in the central sands region of Wisconsin. It included a panel discussion with George Kraft, hydrologist with UW Extension in Stevens Point; Tamas Houlihan, executive director of the Wisconsin Potato and Vegetable Growers Association; Scott Krug, Republican Party Assemblyman from the Town of Rome; and Katrina Shankland, Democratic Party Assemblywoman from Stevens Point. 

If you would like to listen to the podcast of this program, click this link

Sarah DeWeerdt: Bird Deaths From Window Collisions →

Conservation Magazine:

“Collisions with windows are one of the biggest human-related causes of bird deaths in the United States, responsible for up to one billion avian fatalities every year. That’s as much as 9 percent of the country’s entire bird population.

In general, the more windows and the bigger windows a building has, the more dangerous it is for birds. Many green buildings are designed with lots of windows to reduce the need for artificial light and heating. So there can be a tension between saving energy and saving birds.

Glass with etched patterns, mullions, or UV-reflective films can help birds recognize windows as a barrier and avoid flying into them. But scientists have incomplete knowledge of how well these measures work, as well as what aspects of buildings and biology make birds more vulnerable to window strikes in the first place.

Two recent studies conducted on opposite sides of the country fill in some of these details...”

Some alternations of our buildings and bird-friendly designs appear reasonable and responsible. Now if we can reduce mortality due to our domesticated cats...

Thompson and Rogers: Global Warming Threatens Lake Trout→

Thunder Bay News:

“Warming water from climate change is beginning to encroach on the habitat of Northwestern Ontario’s cold water fish. Research conducted at the Experimental Lakes Area shows the region’s temperature has warmed 0.4 C over each of the last five decades. Shorter winters are heating surface water and delaying lake trout spawning.

The runoff from increasing summer rain is causing a tea-like discolouration, affecting the water’s heat distribution and compounding the change. Added together, fish biologist Lee Hrenchuk can see consequences for aquatic ecosystems beginning to show.

“The average size of an adult fish has been decreasing over time and we’re seeing this mostly in the cold water fish species that are really dependent on having good spring periods and good fall periods where they can do a lot of eating,” Hrenchuk said.”

Jim Erickson: Voluntary Actions May Not Solve Lake Erie's Pollution Problem→

University of Michigan:

“Large-scale changes to agricultural practices will be required to meet the goal of reducing levels of algae-promoting phosphorus in Lake Erie by 40 percent, a new University of Michigan-led, multi-institution computer modeling study concludes.

The main driver of the harmful algal blooms is elevated phosphorus from watersheds draining to Lake Erie’s western basin, particularly from the heavily agricultural Maumee River watershed. About 85 percent of the phosphorus entering Lake Erie from the Maumee River comes from farm fertilizers and manure.

The new study, which integrates results from six modeling teams, was released today by the U-M Water Center. It concludes that meeting the 40-percent reduction target will require widespread use of strong fertilizer-management practices, significant conversion of cropland to grassland and more targeted conservation efforts.

”Our results suggest that for most of the scenarios we tested, it will not be possible to achieve the new target nutrient loads without very significant, large-scale implementation of these agricultural practices,” said U-M aquatic ecologist Don Scavia, lead author of the new study and director of the Graham Sustainability Institute.”

You can ask farmers to help, you can pay farmers to help, you can tell farmers to help, or is there another way? 

Scott Johnson: Monarchs at Peril→

ArsTechnica:

“Monarch butterflies could disappear from Eastern US within 20 years. As population declines, the prognosis is not encouraging.

In colder climes, signs of spring can lift a heavy weight from a tired, frozen spirit. Trees bud, flowers bloom, and migratory species trickle in to announce the approach of summer. In the US, one of those species is a floppy orange gem: the monarch butterfly. These insects winter in amazingly dense clusters in Mexican forests before making a staggeringly long journey (one that spans multiple generations, in fact) to summer homes to the north.

But in recent years, the population of monarchs that stay east of the Rockies has dropped like a rock. Precise population numbers are difficult to come by, but estimates kept by the US Fish and Wildlife Service show about an 80 percent decline over the last decade.”

Ross Andersen: Insight from Lake Sediment→

Atlantic:

“On a spring morning in New Hampshire, 2,000 years ago, sunlight struck a black cherry tree, opening its white-and-yellow blossoms. As the tree swayed gently in breeze, spiky, spherical pollen grains spilled out of its flowers, and floated up through the limbs and leaves of the canopy, before drifting down to the still surface of a nearby lake. Cool water stalled the pollen’s descent, but still, it kept falling, riding the currents all the way to the lake’s bottom, where it mixed with silt and slowly hardened into sediment.

Time piled new layers of mud and soil atop the pollen, pushing it deeper into the Earth. For two millennia, it continued to sink at that geologic pace, until suddenly, and with some violence, it was slurped up to the surface, through an aluminum tube.

Sitting on a floating platform, a small team of scientists pulled the pollen up as part of a cylinder of sediment, a core bored out of the lake bottom. A core looks like nothing more than a cross-section of muck, but each of its sedimentary slices is an archive, packed with fragments of sticks and leaves, charred remains of wood—and enough pollen grains to census the trees that once surrounded the lake.”

Kevin Duffy: Rare Orchid Threatened with Global Warming→

Great Lakes Echo:

“As climate change threatens wet landscapes with persistent and intense droughts, natural resource managers look for ways to preserve the remaining habitats of the rare species that dwell in them.

It’s not easy. “There’s a big problem with managing climate sensitive species,” said Sue Galatowitsch, professor of fisheries, wildlife and conservation biology at the University of Minnesota.

That problem – the uncertainty of the future climate – was the focus of a recent study of how best to protect a rare orchid in Minnesota called the small white lady’s slipper.

“Management of very specific, local sites is important because conservation is really a boots on the ground effort,” Galatowitsch said. State plans guide policy, but day-to-day decision-making usually happens one place or person at a time.”

Nathan Collins: Models Often Better Than Guessing→

Pacific Standard:

““We pitted University students in introductory environmental science courses against the models and found that even when the models were completely wrong they still on average made better decisions than the humans did,” Holden writes, perhaps because the models force environmental managers to think more clearly about their assumptions. “Without the aid of modeling, decision maker assumptions become less transparent, and it is easier for them to make biased decisions.””

Eric Anondson: MN Distressed Communities→

streets.mn:

“This is really fascinating to see visually and might even fit with many assumptions of what particular areas of the metro area are like. Go mouse around the interactive map at the link above, the zip codes reveal the statistics for each zip code.

But I had one particular issue that I couldn’t shake. The zip code map of Minnesota’s distressed communities had a worrying similarity with another map I posted about a few weeks ago. The Minnesota Carbon Donut. I immediately thought of the famous XKCD comic on heat maps. The map of economic distress correlates quite closely with the carbon footprint ring. Huh? I’m going to have to dwell on that a bit more, but I think how closely they match up deserves some attention.”

DIC Data for U.S. Zip Codes by State

Erica Goode: Non-Native Species Aren’t Always Unwanted→

New York Times:

“Dr. Thompson and other scientists have called for a more nuanced approach to evaluating whether the presence of a species is harmful or beneficial. Eradicating most invasive species is virtually impossible in an era of globalization, they note. And as climate change pushes more species out of their home ranges and into new areas, the number of so-called invaders is likely to multiply exponentially.

Yet the notion that a species should not be judged on its origins is highly controversial, as Mark Davis, a biology professor at Macalester College in Minnesota, discovered when he and 18 other researchers submitted an article in 2011 saying just that in the journal Nature...

But in the five years since that contentious exchange, the idea that invasive species should be assumed guilty until proven innocent has begun to wane, the shift prompted in part, Dr. Davis speculated, by concerns over the use of chemical pesticides and the disruption of landscapes caused by many eradication efforts.”

See this blog article

Nathaniel Rich: DuPont's Sin and Rob Bilott's Courage→

New York Times:

“Just months before Rob Bilott made partner at Taft Stettinius & Hollister, he received a call on his direct line from a cattle farmer. The farmer, Wilbur Tennant of Parkersburg, W.Va., said that his cows were dying left and right. He believed that the DuPont chemical company, which until recently operated a site in Parkersburg that is more than 35 times the size of the Pentagon, was responsible. Tennant had tried to seek help locally, he said, but DuPont just about owned the entire town. He had been spurned not only by Parkersburg’s lawyers but also by its politicians, journalists, doctors and veterinarians. The farmer was angry and spoke in a heavy Appalachian accent. Bilott struggled to make sense of everything he was saying. He might have hung up had Tennant not blurted out the name of Bilott’s grandmother, Alma Holland White.

White had lived in Vienna, a northern suburb of Parkersburg, and as a child, Bilott often visited her in the summers. In 1973 she brought him to the cattle farm belonging to the Tennants’ neighbors, the Grahams, with whom White was friendly. Bilott spent the weekend riding horses, milking cows and watching Secretariat win the Triple Crown on TV. He was 7 years old. The visit to the Grahams’ farm was one of his happiest childhood memories.

When the Grahams heard in 1998 that Wilbur Tennant was looking for legal help, they remembered Bilott, White’s grandson, who had grown up to become an environmental lawyer. They did not understand, however, that Bilott was not the right kind of environmental lawyer. He did not represent plaintiffs or private citizens. Like the other 200 lawyers at Taft, a firm founded in 1885 and tied historically to the family of President William Howard Taft, Bilott worked almost exclusively for large corporate clients. His specialty was defending chemical companies. Several times, Bilott had even worked on cases with DuPont lawyers. Nevertheless, as a favor to his grandmother, he agreed to meet the farmer. ‘‘It just felt like the right thing to do,’’ he says today. ‘‘I felt a connection to those folks.’’”

Natalie Wolchover: Longer Time to Recover is a Warning Sign→

Atlantic:

“Systems that exhibit such “critical transitions” tend to be so complicated and riddled with feedback loops that experts cannot hope to calculate in advance where their tipping points lie—or how much additional tampering they can withstand before snapping irrevocably into a new state.

At Peter Lake, though, Carpenter and his team saw the critical transition coming. Rowing from trap to trap counting wriggling minnows and harvesting other data every day for three summers, the researchers captured the first field evidence of an early-warning signal that is theorized to arise in many complex systems as they drift toward their unknown points of no return.

The signal, a phenomenon called “critical slowing down,” is a lengthening of the time that a system takes to recover from small disturbances, such as a disease that reduces the minnow population, in the vicinity of a critical transition. It occurs because a system’s internal stabilizing forces—whatever they might be—become weaker near the point at which they suddenly propel the system toward a different state.”

John Myers: Lakes Warming Up

Duluth News Tribune:

“Lakes across the globe are warming faster than oceans and air temperatures in a sign that climate change may be affecting freshwater environments more than anyone had previously understood.

That’s the finding of a report published in the journal Geophysical Research Letters and announced Wednesday at the fall meeting of the American Geophysical Union. The study found lakes worldwide warmed an average of 0.61 degrees Fahrenheit per decade between 1985 and 2009.

In northern climates, that increase averaged 1.3 degrees per decade. “The world’s deepest ice-covered lakes warmed twice as fast as the overlying air temperatures,” the report notes.

Temperature is among the most basic factors in lake ecosystems, the study’s authors noted, and when “the temperature swings quickly and widely from the norm, life-forms in a lake can change dramatically and even disappear.””

How long will some people keep their head in the sand? Justice would be served if only those descendants of today's global warming deniers paid the costs of inaction.