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The Importance Of Wildlife Crossings | Earth Wise

September 23, 2022 By EarthWise Leave a Comment

Highway accidents involving animals are a big problem for both people and animals. According to the National Highway Traffic Safety Administration, motorists in the United States kill one to two million large animals every year. About 200 people are killed annually in the U.S. as a result of those collisions with animals.

These crashes are expensive, too. Deer-vehicle collisions cost an average of more than $8,000 each; elk-vehicle collisions cost about $25,000; and moose-vehicle collisions cost more than $44,000.

One solution that has been quite effective around the world in reducing car-animal collisions is wildlife overpasses and underpasses. They are designed to help animals move in search of food and to escape predators and wildfires. These traffic-spanning bridges and tunnels have been popular in Europe since the 1950s. They look much like regular overpasses for cars but are decked out with native flora. The underpasses, which assist shyer and smaller animals, are typically invisible to drivers.

According to a new economic analysis by researchers at Washington State University, wildlife crossings in Washington State save roughly $235,000 to $443,000 every year per structure.

Wildlife crossing structures range in cost from $500,000 for a tunnel-like underpass to more than $6 million for a broad bridge. There may soon be many more wildlife crossing structures across the country since $350 million was allotted in the federal Infrastructure Investment and Jobs Act signed into law in 2021.

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Wildlife crossings potentially save millions annually in Washington state

How wildlife bridges over highways make animals—and people—safer

Photo, posted March 24, 2017, courtesy of Jeffrey Beall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Dead Zone In The Gulf Of Mexico | Earth Wise

July 6, 2020 By EarthWise Leave a Comment

The Gulf of Mexico has an area of low to no oxygen in the water that can kill fish and other marine life. It is an annual event that is primarily caused by excess nutrient pollution from human activities in urban and agricultural areas throughout the Mississippi River watershed. When these excess nutrients reach the Gulf, they stimulate the overgrowth of algae, which eventually die and decompose, depleting the oxygen in the water as the algae sink to the bottom.

These low oxygen levels near the bottom of the Gulf cannot support most marine life. Some species – among them many fish, shrimp, and crabs – swim out of the area, but animals that can’t swim or move away are stressed or killed by the low oxygen. The dead zone in the Gulf occurs every summer.

A recent forecast for this summer’s dead zone predicts that the area of low or no oxygen will be approximate 6,700 square miles, which is roughly the size of Connecticut and Delaware combined. This is about 1,100 square miles smaller than last year’s dead zone and much less than the record of 8,776 square miles set in 2017. But it is still larger than the long-term average size of 5,387 square miles.

Making comparisons to the long-term average ignores the fact that the long-term average itself is unacceptable. The dead zone not only hurts marine life, but it also harms commercial and recreational fisheries and the communities they support. The actions that have been taken so far to reduce pollution in the Mississippi watershed are clearly not sufficient to drastically reduce the dead zone in the Gulf.

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Large ‘dead zone’ expected for Gulf of Mexico

Photo, posted October 17, 2017, courtesy of NOAA’s National Ocean Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Fresh Produce | Earth Wise

May 26, 2020 By EarthWise Leave a Comment

Fresh fruits and vegetables can sometimes become contaminated by microorganisms during their long journey from fields to restaurants and grocery stores. Contaminated produce can spoil other produce, which increases the number of fruits and vegetables in the supply chain that can cause illnesses.

In order to prevent this cross-contamination between produce, researchers from Texas A&M University have designed a coating that can be applied to food-contact surfaces, like buckets, rollers, and conveyor belts. The newly-created dual-function coating is both water-repellent and germicidal. In other words, it can both repel and kill. Without water, the researchers say bacteria can’t stick or multiply on surfaces, drastically reducing contamination.

To make this dual-function coating, the researchers chemically-attached a thin layer of silica to an aluminum sheet. They then added a mixture of silica and lysozyme, a naturally-occurring germicidal protein found in egg whites and tears. Together, the silica-aluminum and the silica-lysozyme formed microscopic bumps and crevices. According to the research team, this rough texture, albeit microscopic, is the key to the coating’s superhydrophobic properties.

The researchers tested the coating’s effectiveness at curbing the growth of two strains of disease-causing bacteria: Salmonella and Listeria. Upon review, the number of bacteria found on the dual-coating surfaces was 99.99% less than what was found on the uncoated surfaces.

Despite the success in preventing bacterial spread, the research team said more research needs to be done to see how well the coating works for mitigating viral cross-contamination. Since the coating would need to be reapplied after a certain amount of use, the researchers also plan to develop more permanent, dual-function coatings.

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New dual-action coating keeps bacteria from cross-contaminating fresh produce

Photo, posted April 14, 2012, courtesy of U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Kind Of Antibiotic | Earth Wise

March 10, 2020 By EarthWise Leave a Comment

Antimicrobial resistance is a serious and growing problem for public health. Over time, more and more types of bacteria have become resistant to known antibiotics making it very difficult to treat various kinds of infections.

A new group of antibiotics with a unique approach to attacking bacteria has been discovered at McMaster University in Canada, representing a promising new clinical approach in the fight against antimicrobial resistance.

The newly found corbomycin and the lesser-known complestatin have a never-before-seen way to kill bacteria, namely, breaking the function of the bacterial cell wall. Bacteria have a wall around the outside of their cells that gives them shape and is a source of strength. Antibiotics like penicillin kill bacteria by preventing building of the wall, but the new antibiotics work by doing the opposite – they prevent the wall from being broken down. Breaking down the cell wall is critical for cells to divide. In order for bacteria to grow and spread, they need to expand and divide. By completely blocking the breakdown of the wall, it is as if the bacterium is trapped in a prison and can’t expand or grow.

The researchers demonstrated in mice that these new antibiotics can block infections caused by the drug resistant Staphylococcus aureus which is a group of bacteria that can cause many serious infections.

The researchers believe this new approach can be applied to other antibiotics and lead to the discovery of new ones with different mechanisms of action. This study found one completely new antibiotic, but since then, they have found a few others in the same family that have this same new mechanism.

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Antibiotics discovered that kill bacteria in a new way

Photo, posted March 15, 2012, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Getting Rid Of Plastic Here And Abroad

May 23, 2019 By EarthWise Leave a Comment

Efforts in the fight against plastic pollution are really stepping up these days.

New York State lawmakers have agreed to impose a statewide ban on most types of single-use plastic bags from retail sales. The ban would be the second statewide ban after California, which banned the bags in 2016. Hawaii effectively also has such a ban since all of the state’s counties have their own bans.

The New York ban would begin next March and would forbid stores from providing customers with single-use plastic bags. There are a number of exceptions, including food takeout bags in restaurants, bags used to wrap deli or meat counter products, and newspaper bags. New York counties could opt into a plan to charge a 5-cent fee on paper bags, with proceeds going to the state’s Environmental Protection Fund. Some environmentalists point out, however, that paper bags have their own issues. While they do decompose in landfills, they have a substantial carbon footprint since they are made from wood and being heavier, they are more costly to ship. Business groups are concerned about the forthcoming ban based on increased costs.

Meanwhile, European Union member states have reached a provisional agreement to introduce restrictions on single-use plastic products. In 2021. European citizens will say goodbye to plastic cutlery, plastic plates and plastic straws among other products.

According to the European Commission, plastics make up 85% of beach litter in the Mediterranean. Large plastic pieces injure, suffocate, and often kill marine animals but microplastics have reached record levels of concentration – over a million fragments per square kilometer – in the Mediterranean.

Both here and abroad, the war on plastics is heating up.

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