Poll the audience: Using data from citizen science to keep wild birds in flight

Read the full story from Utah State University.

New research examines the accuracy of information produced by citizen science apps for monitoring bird populations and found that it could actually offer a lot of utility for researchers, with some caveats.

Habitat protection alone doesn’t guarantee species protection

Read the full story at Anthropocene.

In a wide-ranging study, scientists tracked how 27,000 waterbird populations fared in 1,500 protected areas—compared to similar unprotected areas . Their results are instructive.

A community of seed savers has a recipe to revive rare varieties of collard greens

Read the full story from NPR.

Ira Wallace ambles around the butcher block countertop in the kitchen she shares with a community of farmers in central Virginia. She has separated a single leaf from the large baskets of unusual, parti-colored collard greens she got from a friend’s farm. Its creamy-white veins stretch upward across the green leaf, narrowing as they reach purple-tinged tips.

“Purple is a color that develops in the winter much more strongly,” Wallace explains, as she probes the frost-damaged leaf. “But look at that color! And that’s anthocyanins. They’re supposed to make you healthier.”

These aren’t commercially produced collard greens typically sold in supermarkets or restaurants. Many of the heirloom varieties Wallace and her friends grow are rare, some once teetering on extinction. Other types can likely be found in backroad gardens of aging stewards, but countless varieties have vanished in the U.S.

There was once a kaleidoscope of diversity in collards, as people diligently collected and replanted seeds, passing them from one generation to the next to preserve the qualities they found most important. Collards — an inexpensive, nutrient-rich vegetable — became a staple for many Southern families, especially African Americans trying to feed their families healthy food year-round.

Earth Day groundbreaking for world’s largest wildlife crossing

Read the full story at Construction Dive.

Endangered big cats and other animals will soon get a way to safely traverse a 10-lane Los Angeles-area highway. A new wildlife crossing broke ground on Earth Day, April 22, according to the National Wildlife Federation, and will be the largest of its kind in the world.

The Wallis Annenberg Wildlife Crossing is a public-private partnership between the National Wildlife Federation and the California government. Other parties involved in the creation and construction of the project include the National Park Service and the city of Agoura Hills, California, where the crossing is located, according to the release.

Private donations made up 60% of the $90 million price tag, according to The Guardian, and the project is expected to open in early 2025. Caltrans, California’s Department of Transportation, will develop, build and maintain the crossing.

Indianapolis’ urban forests worth $258 million. But they are disappearing to development.

Read the full story in the Indianapolis Star.

Indianapolis’ trees are worth a lot of money — nearly $258 million a year, according to a recent report. That’s not the price they would fetch for lumber if they were cut down, however. 

Quite the opposite, in fact: That’s the value of leaving the trees standing. 

The report identified more than 4,300 forested areas, defined as one acre or more of trees, across Marion County. Those pockets of green provide tremendous, yet often overlooked, benefits to residents. They help control flooding, improve air and water quality, increase property values and enhance quality of life. 

But the city’s urban forests are dwindling rapidly — being erased from the map and neighborhoods by encroaching development. And every tree cut down or pushed over by a bulldozer chips away at those important benefits.

A botanical mystery solved, after 146 years

Read the full story at Atlas Obscura.

How a young illustrator’s attention to detail—and a determined Victorian woman’s legacy—led to the discovery of a new species in an old painting.

Powderhorn Lake Connectivity Project

Powderhorn Lake is part of one of the few remaining examples of the dune and swale topography – sandy ridges interspersed with water pockets – that once characterized the Calumet Region along the south shore of Lake Michigan. The area is home to 100 bird species, 250 plant species and 2,500 insect species. In addition to reconnecting water flow to Lake Michigan, this project will allow fish passage between the lakes, install water control structures to help prevent future community flooding, and increase hemi-marsh habitat. This work aligns with the Great Lakes Restoration Initiative objective of protecting and restoring communities of native aquatic and terrestrial species important to the Great Lakes.

Abundance, exploitation, recovery: A portrait of South Georgia

Read the full story from the New York Times.

A series of ecological initiatives, including the eradication of several invasive species, has dramatically revived the life and landscape of this remote sub-Antarctic island.

Snowbound: Big trees boost water in forests by protecting snowpack

Read the full story from Utah State University.

Trees have a complex relationship with snow and energy as the season warms up, but new research shows that big trees can protect melting snowpacks in water-stressed environments.

To protect wildlife from free-roaming cats, a zone defense may be more effective than trying to get every feline off the street

Killer on the loose. Alex Walker via Getty Images

by Daniel Herrera, George Mason University and Travis Gallo, George Mason University

Should domestic cats be allowed to roam freely outdoors? It’s a contentious issue. Those who say yes assert that they’re defending outdoor cats and the people who care for them. Critics respond that free-roaming cats kill so many birds, reptiles, mammals and important insects like butterflies and dragonflies that they threaten biodiversity on a global scale.

As conservation biologists familiar with these clashing viewpoints, we wondered whether there was room for a more nuanced strategy than the typical yes/no standoff. In a recently published study, we used camera traps at hundreds of sites across Washington, D.C., to analyze the predatory behavior of urban free-roaming cats. The cameras recorded all cats that passed them, so our study did not distinguish between feral cats and pet cats roaming outdoors.

Our data showed that the cats were unlikely to prey on native wildlife, such as songbirds or small mammals, when they were farther than roughly 1,500 feet (500 meters) from a forested area, such as a park or wooded backyard. We also found that when cats were approximately 800 feet (250 meters) or farther from forest edges, they were more likely to prey on rats than on native wildlife.

Since the average urban domestic cat ranges over a small area – roughly 550 feet (170 meters), or one to two city blocks – the difference between a diet that consists exclusively of native species and one without any native prey can be experienced within a single cat’s range. Our findings suggest that focusing efforts on managing cat populations near forested areas may be a more effective conservation strategy than attempting to manage an entire city’s outdoor cat population.

Cats have an instinctual drive to hunt, even when they’re well-fed, and pursue many types of prey.

Cats on the loose

Free-roaming cats are a common sight in Washington, D.C., which has a feline population of 200,000. Like many cities, Washington has had its share of cat management controversies.

Professionals on either side of the free-roaming cat debate largely agree that cats are safest when kept indoors. An outdoor cat’s lifespan generally peaks around 5 years, compared with 10 to 15 years for an indoor cat. Free-roaming cats face numerous threats, including vehicle collisions and contact with rat poison. Acknowledging these risks, most animal welfare organizations encourage an indoor-only lifestyle.

Similarly, there is little disagreement that cats hunt; for centuries humans have used them for rodent control. But invasive rats, which are often the target of modern rodent control, can grow too large to be easy prey for cats. In response, cats also pursue smaller species that are easier to catch. Studies have linked cats to 63 extinctions globally and estimated that cats kill 12.3 billion wild mammals annually in the U.S. alone.

Disagreements arise around handling cats that already live outside. Population management programs often utilize trap-neuter-return, or TNR – a process in which cats are trapped, spayed or neutered and re-released where they were caught.

In theory, TNR limits population growth by reducing the number of kittens that will be born. In reality it is rarely effective, since 75% of individual cats must be treated every year to reduce the population, which is often not feasible. Regardless, reproduction itself is not what most worries conservation biologists.

Feline invaders

Today the Earth is losing wild species at such a rate that many scientists believe it is experiencing its sixth mass extinction. In this context, free-roaming cats’ effects on wildlife are a serious concern. Cats have an instinctual drive to hunt, even if they are fed by humans. Many wildlife populations are already struggling to survive in a rapidly changing world. Falling prey to a non-native species doesn’t help.

Cats aren’t picky hunters but will pounce on the easiest available prey. This generalist predatory behavior contributes to their reputation as one of the most damaging invasive species. In our view, however, it could also be a key to limiting their ecological impact.

Silhouettes of predator species above bar charts representing threatened species they kill.
This graphic shows the numbers of threatened and extinct bird (B), mammal (M) and reptile (R) species negatively affected by invasive mammalian predators. Gray bars are the total number of extinct and threatened species, and red bars are extinct species. Predators (L to R) are the cat, rodents, dog, pig, small Indian mongoose, red fox and stoat. Doherty et al., 2016, CC BY-ND

Managing cats based on their behavior

Since cats are generalist predators, their wild-caught diet tends to reflect the local species that are available. In areas with more birds than mammals, like New Zealand, birds are cats’ primary prey. Similarly, cat diets in the most developed portions of cities likely reflect the most available prey species – rats.

While cats top the list of harmful invasive species, rats aren’t far behind. In cities, rats spread disease, contaminate food and damage infrastructure. There aren’t many downsides to free-roaming cats preying on rats.

City centers have no shortage of rats, which can live anywhere, including parks, subways, sewers and buildings. But native animals tend to stay in or near areas with sufficient outdoor habitat, like parks and forested neighborhoods. When cats hunt in these same spaces, they are a threat to native wildlife. But if cats don’t share these spaces with native species, the risk declines dramatically.

The National Park Service built a specially designed 5-mile fence on the island of Hawaii to protect endangered petrels from predation by feral cats.

Conservation funding is limited, so it’s critical to choose effective strategies. The traditional approach to cat management has largely consisted of attempting to prohibit cats from being loose altogether – an approach that’s incredibly unpopular with people who care for outdoor cats. Despite calls for outdoor cat bans, few have been enacted.

Instead, we suggest prioritizing areas where wildlife is most at risk. For example, cities could create “no cat zones” near urban habitats, which would forbid releasing trap-neuter-return cats in those areas and fine owners in those areas who let their cats roam outdoors.

In Washington, D.C., this would include forested neighborhoods like Palisades or Buena Vista, as well as homes near parks like Rock Creek. As we see it, this targeted approach would have more impact than citywide outdoor cat bans that are unpopular and difficult to enforce.

Hard-line policies have done little to reduce outdoor cat populations across the U.S. Instead, we believe a data-driven and targeted approach to cat management is a more effective way to protect wildlife.

Daniel Herrera, PhD Student in Environmental Science and Policy, George Mason University and Travis Gallo, Assistant Professor of Urban Wildlife Ecology and Conservation, George Mason University

This article is republished from The Conversation under a Creative Commons license. Read the original article.