Why Are Nebraska’s Birds Turning White?

Photo 1: A. The first barn swallow with partial leucism we caught in 2018; B. An example of the white feathers we have found in many individuals; C.  An example of tail streamer deformation and asymmetry; D. A barn swallow with typical melanin coloration.

I teach general biology at – (CCC-C) in Nebraska, where I hold ecology lab courses at a nearby creek with students in waders performing water quality tests. This “creek” is a glorified agricultural drainage ditch, bordered by farmland in a state that crop-dusts on a regular basis throughout the summer months. I saw birds nesting underneath the bridge once and decided on a whim to mist net during a lab session. Mist nets are used to capture birds and can only be purchased with proof of a U.S. Fish and Wildlife collecting permit. As students took samples, I extracted the bird—a barn swallow (photo 1, A)—that started this project.

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Radioactive Waste Cleanups After the Manhattan Project: Lessons Learned

The following post is one of a series previewing the research that will be presented at the (SciCon4), 14–18 November 2021

A guest post by Karen Keil, U.S. Army Corps of Engineers

Nuclear contamination warning sign, Adobe Stock Image

Radioactivity was first discovered over a century ago (circa 1890s). Within 50 years we were harnessing that incredible power to build an atomic bomb, in an effort to end World War II. However, left a . Over the last several decades, we have spent billions of dollars cleaning up the environmental impacts of this waste, with efforts still . What have we learned from this process? Although radioactive waste products are now considered “legacy” contaminants, back in the day they could have been classified as “contaminants of emerging concern”—substances whose recently discovered environmental consequences pose challenging problems to environmental scientists. What have we learned from the cleanup efforts for legacy radioactive waste? Can we apply the lessons learned to new contaminants?

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Integrating Knowledge on the Distribution and Maternal Transfer of Organic Pollutants to Advance Sea Turtle Conservation


The following post is one of a series previewing the research that will be presented at the SETAC North America 42nd Annual Meeting (), 14–18 November 2021.

A guest post by Cynthia C. Muñoz and Peter Vermeiren, Radboud University, The Netherlands

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Knowledge regarding the internal distribution and subsequent maternal transfer of organic pollutants—such as (PCBs), once used in electical equipment and plastics; (OCPs), and (PBDEs), which make materials nonflammable—within organisms is of critical importance to scientists who interpret tissue-specific biomonitoring results and refine risk assessments. Although the manufacture and/or use of most of these chemicals were banned decades ago, they persist in the environment and accumulate in wildlife. This is particularly true for long-lived organisms, such as sea turtles, where pollution burdens build up over time and affect health later in life. Moreover, organic pollutants can accumulate over many years before being transferred from the mother to its offspring, where they can interfere with critical development processes. For example, maternal transfer of organic pollutants into yolk, through the placental barrier, or during lactation has been linked to decreased survival rates and impaired embryo and juvenile development in several long-lived vertebrate species. Yet knowledge on the internal and maternal distribution of organic pollutants remains limited for many such species, due to ethical, economic, and logistical restrictions on sampling them, as many are threatened or endangered. Additionally, a diverse chemical universe of legacy, new, and emerging organic pollutants is present in the environment, of which the behavior within the environment and upon contact with long-lived species is largely unknown. In short, the challenge of refining risk assessments specific to the characteristics of long-lived species, such as sea turtles, is complex, without an easy solution.

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We Should Take a Holistic Approach to Environmental Risk Assessment Following Oil Spills

A guest editor post by Sharon Hook, CSIRO Oceans and Atmosphere

With the recent pipeline leak in the waters off of , USA, oil spills are once again in the headlines. We are hearing the concerns of the affected communities about what the consequences of this spill will be for wildlife, fisheries, and safe use of the beaches. After all of the decades of oil spill-related research, there is still a lot of uncertainty about the environmental impacts of oil spills. It is a good opportunity, to ask ourselves as environmental scientists, if we are asking the right questions in our research into the impacts of oil spills, and if we are setting up our studies with the most environmentally relevant approaches.

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Evolution by Pesticides: Evidence of Evolution in American Alligators Affected by Endocrine Disrupting Chemicals

The following post is one of a series previewing the research that will be presented at the SETAC North (SciCon4), 14–18 November 2021.

A guest post by Yeraldi Loera, Ph.D. student at Princeton University

Solo gator. Photo courtesy of the author.

Instances of are widespread across the globe. Pesticides are commonly used in agriculture to combat pests, but can also harm other, non-targeted organisms. Exposure to some pesticides can lead to disruption in the endocrine system, altering reproductive development and fitness. showed this kind of disruptive effect across populations of American alligators (Alligator mississipiensis) that were exposed to a pesticide (DDT) spill in Lake Apopka, Florida. Surprisingly, in the same region showed a rebound in the population following their exposure, suggesting possible evolved resistance to pesticide contamination.

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An Unexpected Source of Mercury: Greenland’s Glaciers

Greenland, the largest island in the world not considered its own continent, lies above the Arctic Circle with the exception of its Southern tip. Ice—the Greenland Ice Sheet—is everywhere but is rapidly becoming a major contributor to sea level rise as it melts because of climate change. Now, a shows that the resulting freshwater (or meltwater) runs off to the ocean taking along an unexpected and toxic companion—mercury, a chemical that when transformed into methylmercury bioaccumulates and biomagnifies in fish, shellfish, and animals that eat fish, causing nervous system damage and other deleterious effects in humans and wildlife.

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Understanding Underwater Sounds: Evaluating Risks of Human Activities

A guest post by Andrew McQueen, US Army Corps of Engineers

Researchers around the world are focusing more on the role of anthropogenic (human-made) sounds in marine ecosystems. In the last half century, as we have industrialized and expanded our use of the “blue” ocean economy (maritime transport, fisheries, and renewable energy), some regions have observed incremental increases of anthropogenic underwater sounds. However, the ecological consequences, or risks, of these changing underwater soundscapes remain largely unknown.

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Lost Wilderness: Restoring both Habitat and Animal Species

A month after the death of Henry David Thoreau, The Atlantic “Walking,” which “extolled the virtues of immersing oneself in nature and lamented the inevitable encroachment of private ownership upon the wilderness.” It included Thoreau’s famous line “In wildness is the preservation of the world”—eight powerful words that played a major role in saving places such as Yosemite and Cape Cod from human-caused environmental destruction, inspiring the creation of the US National Parks system. Upon signing the US Wilderness Act in 1964, President Lyndon B. Johnson : “If future generations are to remember us with gratitude rather than contempt, we must leave them more than the miracles of technology. We must leave them a glimpse of the world as it was in the beginning, not just after we got through with it.” Continue reading

Biodiversity Under Attack in Rivers: Human Activities Cause Changes All Around the Globe

On 18 February, the United Nations Environment Programme (UNEP) released a report highlighting the three major emergencies that are currently challenging the entire planet— climate, biodiversity, and pollution. “” is based on evidence from global environmental assessments. “Humanity is waging war on nature. This is senseless and suicidal. The consequences of our recklessness are already apparent in human suffering, towering economic losses, and the accelerating erosion of life on Earth,” said António Guterres, Secretary-General of the United Nations in the report foreword.

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Antimicrobial Resistance: Using Water Fingerprinting to Assess Usage and Fate of Antibiotics

The discovery of antibiotics unquestionably changed the face of public health. However, pathogenic tolerance to these drugs is ever increasing, and it’s becoming a . The topic of antimicrobial, or antibiotic resistance (AMR) has existed for almost as long as the initial discovery of penicillin in the late 1920s; the difference now is the lack of new drugs being developed as alternatives. The discovery of new antibiotics is of course critical, yet we should be focusing more attention on prevention and containment. Inappropriate usage and disposal, livestock supplements in agriculture, and poor international regulation are some significant contributors; but are often difficult to quantify. One technique that is now being utilized is ‘water fingerprinting.’

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