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Biodiversity Climate Change Conservation Gardening Pollinators, Molluscs and Other Invertebrates Sustainable Living

2023 February Conservation Update

In this post, a fascinating DNA sampling technique; conflicting news about human impact on animal populations; and a cute story about newt rescues in California. We also look at how rising temperatures due to climate change may damage animals; and a study that shows protected areas aren’t designed to protect invertebrates. It turns out we’ve been putting those anti-bird-strike decals on the wrong side of the window; and we look at where your plants come from.

Postcard-sized poo sample collection cards offer an affordable alternative to more cumbersome methods of collecting and storing the genetic information in dung. The cards do not need to be refrigerated and maintain viable DNA for months after collection. Credit: Fred Zwicky

Streamlined DNA for wildlife conservation

A team from University of Illinois at Urbana-Champaign has come up with a new way of sampling DNA that allows scientists to capture genetic information from wildlife without disturbing the animals or putting their own safety in jeopardy. The protocol, tested on elephant dung, yielded enough DNA to sequence whole genomes not only of the elephants but also of the associated microbes, plants, parasites and other organisms—at a fraction of the cost of current approaches. The researchers report their findings in the journal Frontiers in Genetics.

A family of urban raccoons. Photo by Jon Last.

Can urban neighborhoods be both dense and green?

The British Ecological Society reports on a new study from The Nature Conservancy (TNC) that explores how we can make our cities work better for people and wildlife.  By analyzing existing approaches, as well as highlighting cities already creating the right balance of people and wildlife, the study pioneers an alternative method of city design that allows for the accommodation of both denser populations as well as wildlife. “This needn’t be a zero-sum game,” explains senior author and TNC lead scientist for nature-based solutions, Rob Mcdonald. “Having denser cities doesn’t automatically mean less space for nature.”

But, while animals may be able to co-exist happily with humans in urban areas, another study highlights how human incursions into natural areas can disturb wildlife.

Researchers placed camera traps along hiking trails in Glacier National Park during and after a COVID-19 closure. They found that 16 out of 22 mammal species changed the way they accessed areas when humans were present. Credit: Mammal Spatial Ecology and Conservation Lab, Washington State University

Human recreation changes wildlife behavior

Even without hunting rifles, humans appear to have a strong negative influence on the movement of wildlife. A study of Glacier National Park hiking trails during and after a COVID-19 closure adds evidence to the theory that humans can create a “landscape of fear” like other apex predators, changing how species use an area simply with their presence. Researchers found that when human hikers were present, 16 out of 22 mammal species, including predators and prey alike, changed where and when they accessed areas. Some completely abandoned places they previously used, others used them less frequently, and some shifted to more nocturnal activities to avoid humans. The study was published in the journal Scientific Reports. The researchers had also expected to find an effect known as “human shielding,” when human presence causes large predators to avoid an area, providing opportunity for smaller predators and perhaps some prey species to use an area more frequently. In this case, they found this potential effect for only one species, red fox. The foxes were more present on and near trails when the park was open–perhaps because their competitors, coyotes, avoided those areas when humans were around. While the influence of low-impact recreation is concerning, the researchers emphasized that more research is needed to determine if it has negative effects on the species’ survival.

Credit: Unsplash/CC0 Public Domain

Animals at risk from heat waves

More than 40% of all land vertebrates may be subjected to extreme heat events by 2099 under current maximum estimates of future global temperatures, according to a study published in Nature. Prolonged exposure to high temperatures could be dangerous for the future of many species across the globe. Extreme thermal events, a period in which the temperature greatly exceeds a historical threshold, have increased in frequency compared to historical records, exacerbated by climate change caused by human activity. Recurring periods of extreme heat affect wildlife and are associated with increased psychological stress, reduced reproductive output and decreased population sizes, meaning that the continuation of these temperature spikes would pose a substantial threat to future biodiversity.

A ‘Big Night’ for Newts

The New York Times has a heart-warming story about the heroic work of the northern California Chileno Valley Newt Brigade in rescuing amphibians that might otherwise become roadkill as they cross a road from their breeding grounds and their burrows. But newt rescue is just a short-term solution. The group is also fundraising for road modifications that will allow the newts to pass safely underneath.

Black swallowtail on thistle at New Life Retreat. Photo by Carol English.

Protected areas fail insect species

Insects play crucial roles in almost every ecosystem—they pollinate more than 80% of plants and are a major source of food for thousands of vertebrate species—but insect populations are collapsing around the globe, and they continue to be overlooked by conservation efforts. Protected areas can safeguard threatened species but only if these threatened species actually live within the areas we protect. A new study in the journal One Earth found that 76% of insect species are not adequately covered by protected areas.

Northern cardinal. Photo by Jon Last.

What we know about bird window strikes is inside-out

New research from William & Mary published in PeerJ reveals that decals intended to reduce incidents of bird window strikes—one of the largest human-made causes of bird mortality—are only effective if decals are placed on the outside of the window. Researchers found that the patterns on the films and decals placed on the internal surface of windows do not reduce collision because they may not be sufficiently visible to birds.

A fynbos bouquet from South Africa. Credit: Juan Pablo Moreiras/Fauna & Flora

Where do your plants come from?

Tim Knight of Fauna and Flora International asks if we ever ask ourselves where all our garden plants come from? The local garden center or superstore isn’t the answer. Take bulbs, for instance. There’s a common understanding that most bulbs come from The Netherlands. In fact, most wild tulips hail from the mountainous regions of Central Asia. Kyrgyzstan, Tajikistan, Kazakhstan and Uzbekistan—countries not widely recognized as havens of biodiversity—harbor the lion’s share of species. Turkey is also one of the richest areas in the world for bulbs, including familiar garden favorites such as snowdrops, crocuses, cyclamens and, yes, tulips too. It’s easy to forget that these wild relatives are the original source of the endless varieties and hybrid forms that grace our gardens and fill our flower vases. And that they face a variety of threats, from overharvesting and habitat loss to climate change.

Houseplants come from all over, including the popular Monstera, which is an epiphyte, growing on trees in its native South America. With one notable exception, bromeliads are found only in Central and South America. A single species—endangered and known only from Guinea—occurs in West Africa. Most bromeliads are also epiphytes, but the one that we’re most familiar with—though you may not think of it as a bromeliad—grows on the ground and produces one of our most popular tropical fruits, the pineapple.

White Christmas cactus. Photo by R. Last.

Cacti may be famous for their tolerance of extreme heat and drought—and plummeting temperatures at night—but they’re not confined to hotspots like the American Midwest and Mexico. Of the roughly 2,500 species of cactus in the world, quite a few thrive in rainforests or cooler climes. The Christmas cactus is native to damp forest in the coastal mountains of Brazil.

The article goes on to detail the origins of orchids (pretty much from every continent, except Antarctica); where cut flowers come from; and what makes the fynbos in South Africa so special. Mr. Knight concludes by urging gardeners to pay attention to the origins of plants they purchase and avoid those that come from unsustainable sources.

Categories
Phenology

Different Rhythms for Urban Mammals

[Editor’s note: Per Wikipedia, phenology is the study of periodic events in biological life cycles and how these are influenced by seasonal and interannual variations in climate, as well as habitat factors.]

Photo by Jon Last.

Some mammals shift their schedules in urban environments: When visiting cities, coyotes seem to prefer the nightlife while deer and squirrels would rather be home before dark. That’s the finding of new research from University of Utah (“the U”) scientists who found that mammals in urban environments shifted the timing of their daily activities, likely to avoid encountering humans. With the help of community volunteers, biologists in the U’s School of Biological Sciences set up a network of more than 300 trail cameras to cover urban sites in the Salt Lake Valley as well as sites in the Uinta-Wasatch-Cache National Forest. During the summer months of 2018 and 2019 they logged 19,034 sightings of mammals, focusing specifically on the most abundant: coyote, mule deer, raccoon, squirrel and skunk. But the mammals in the city didn’t all behave like their country cousins. Raccoons and skunks were largely nocturnal in both locations, but coyotes’ activities moved into the night hours in the city and deer and squirrels moved their activity to daytime hours. (In the wild, coyote deer and squirrels spent more active time in the dawn and dusk hours). The study is published in Global Ecology and Conservation.