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.
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.
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.
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.
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.
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.
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.
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.
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.