Genetic diversity is on the decline, but this trend can be slowed

Photo Credit: Tomáš Malík

Genetic diversity is crucial to the ability of animals and plants to adapt to changes in the climate and environment. A major international meta-analysis, published in the journal Nature, shows that genetic diversity is declining globally. But there is hope – effective conservation measures can slow this trend.

For a species to adapt to changes in its environment, a high degree of genetic variation between individual entities is crucial. The greater the diversity, the more likely it is that certain genes will make, for example, a plant more resistant to drought or an animal better adapted to higher temperatures. These genes can then be passed on to future generations and contribute to the survival of the species.

An international research team that includes Uppsala University, Stockholm University and the Swedish Environmental Protection Agency has analyzed genetic changes in 628 species over a period of more than 30 years. The study is based on data from more than 80,000 scientific papers and shows that genetic diversity is declining globally, especially among birds and mammals. At the same time, there are conservation measures that have proven to be effective.

“Overall, the study shows that there are effective conservation methods and data that allow for strategic targeting of actions. But then the genetic component needs to be considered,” says Sara Kurland, Postdoctoral Fellow at the Department of Earth Sciences and one of the researchers behind the study.

New technology lights way for accelerating coral reef restoration

Improving coral feeding habits can have a positive domino effect on the marine ecosystem.
Photo Credit: Francesco Ungaro

Scientists have developed a novel tool designed to protect and conserve coral reefs by providing them with an abundance of feeding opportunities. 

The device, dubbed the Underwater Zooplankton Enhancement Light Array (UZELA), is an autonomous, programmable underwater light that works to draw in nearby zooplankton, microscopic organisms that coral feed on. 

After testing the submersible on two species of coral native to Hawaii over six months, researchers found that UZELA could greatly enhance local zooplankton density and increase the feeding rates of both healthy and bleached coral. Importantly, providing coral with greater amounts of food makes them stronger and more likely to be resilient against certain environmental threats, like heat stress or ocean acidification.

This result is impressive, especially at a time when rising ocean temperatures are forcing entire coral reefs to the cusp of collapse, said

Mount Rainier White-Tailed Ptarmigan Finally Receives a ‘Threatened’ Species Designation

An adult Mount Rainier white-tailed ptarmigan in brown summer plumage. Its feathers change seasonally—white in the winter, white and brown in the spring. Its tail remains white year-round.
Photo Credit: Pete Plage/USFWS

In July, the Mount Rainier white-tailed ptarmigan was officially listed as threatened by the U.S. Fish and Wildlife Service (FWS) under the Endangered Species Act (ESA), 14 years after the Center for Biological Diversity first petitioned for its listing. This designation is meant to help preserve the bird, whose survival depends on the glaciers of the Cascade Mountains of Washington State and British Columbia. It also reflects the complex challenges that alpine-adapted birds face in a warming world.

With its feathered, snowshoe-like feet that allow it to walk on high mountain terrain and its seasonal plumage that provides camouflage year-round, Mount Rainier white-tailed ptarmigans are adapted to high elevation regions above the treeline. They are frequently spotted in areas with mixed rock, snow and alpine plants. Their diet consists of twigs, leaves, buds and seeds of alpine tundra vegetation that only grow in treeless, cold and dry mountainous regions that receive critical moisture from spring snowmelt and summer glacier runoff.

Warming temperatures are accelerating glacier retreat and endangering the bird’s habitat: glaciers in the North Cascades shrunk 56 percent between 1900 and 2009. Mauri Pelto, director of the North Cascade Glacier Climate Project, told GlacierHub that ptarmigans are often spotted along the Shuksan and Ptarmigan Ridges near Mount Baker. In a study, Pelto found that seven of the 13 glaciers along those ridges have disappeared since the mid-1980s. Retreating glaciers risk reduced soil water availability for tundra vegetation and long-term habitat loss associated with warming temperatures.

Life cycles of some insects adapt well to a changing climate. Others, not so much.

A grasshopper, Melanoplus boulderensis, typical of the Colorado Rocky Mountains.
Photo Credit: ©Thomas Naef, 2022

As insect populations decrease worldwide in what some have called an “insect apocalypse,” biologists are desperate to determine how the six-legged creatures are responding to a warming world and to predict the long-term winners and losers.

A new study of Colorado grasshoppers shows that, while the answers are complicated, biologists have much of the knowledge they need to make these predictions and prepare for the consequences.

The findings, published in the journal PLOS Biology, come thanks to the serendipitous discovery of 13,000 grasshoppers collected from the same Colorado mountain site between 1958 and 1960 by a biologist at the University of Colorado Boulder (CU Boulder). After that scientist’s untimely death in 1973, the collection was rescued by his son and donated to the CU Museum, where it languished until 2005, when César Nufio, then a postdoctoral fellow, rediscovered it. Nufio set about curating the collection and initiated a resurvey of the same sites to collect more grasshoppers.

New study could help tackle hidden hunger in Malawi

Fields in Blantyre, Malawi
Photo Credit: Dr Charlotte Hall

Growing fruit trees on farms in rural Malawi could directly improve people’s diets, according to new study by a University of Stirling researcher.

 Around 20% of the population of the African country are undernourished and far more suffer from hidden hunger, meaning they consume enough calories but lack essential micronutrients, such as iron, zinc and vitamin A.

Around 80% of Malawians are involved in smallholder agriculture and a large proportion of the food they consume comes from their own production.

However, conventional agri-food policies continue to promote the increased production of staple cereal crops, and very rarely promote the benefits of fruit trees.

Conservation paradox: Invasive species are often threatened in their native range

The wild rabbit is endangered in its native Europe. In other parts of the world, such as Australia, this species has been introduced and has large populations.
Photo Credit: ©Alexis Lours

Non-native animals are a threat to biodiversity, yet many are themselves threatened with extinction in their areas of origin

Non-native species introduced by humans are among the main causes of global species decline – they were partly responsible for 60 percent of the species that have become extinct worldwide in recent decades. In Central Europe, non-native mammals include species such as the Norway rat, the mouflon and the mink. Now a study led by biologists from the University of Vienna and La Sapienza University in Rome shows that some of these species introduced by humans are themselves endangered in their native range. The study has been published in the current issue of the journal Conservation Letters.

The globalization of the earth is contributing to the introduction of many animal and plant species into new parts of the world. Invasive species can displace native species through competition or transmit new diseases. At the same time, however, some of these non-native species are threatened with extinction in their native ranges. This creates a conservation paradox – because the question now is, should non-native occurrences of species that are endangered in their native range be protected or controlled? However, it was previously unknown how many non-native mammal species this paradox actually applies to. In the new study, the scientists have now quantified this in order to come one step closer to an answer to this paradox.

Older trees help to protect an endangered species

The longest-lived trees in the Pyrenees facilitate the survival of wolf lichen, a species threatened throughout Europe.
Photo Credit: Ot Pasques

The oldest trees in the forest help to prevent the disappearance of endangered species in the natural environment, according to a study led by the University of Barcelona. This is the case of the wolf lichen — threatened throughout Europe —, which now finds refuge in the oldest trees in the high mountains of the Pyrenees. This study reveals for the first time the decisive role of the oldest trees in the conservation of other living beings thanks to their characteristic and unique physiology.

Conserving the oldest trees in forests will be essential to protect biodiversity in forest ecosystems, which are increasingly affected by the impact of global change. This is stated on a new study published in the journal Proceedings of the National Academy of Sciences. The study is signed by the experts Sergi Munné-Bosch and Ot Pasques, from the Faculty of Biology and the UB Biodiversity Research Institute (IRBio).

Canada lynx historic range in US likely wider than previously thought

The lynx might do well in the future in parts of Utah, central Idaho, and the Yellowstone National Park region.
Photo Credit: Zdeněk Macháček

A broader past could mean a brighter future for Canada lynx in the U.S., according to recent research.

The study, published in the journal Biological Conservation, indicates that lynx might do well in the future in parts of Utah, central Idaho and the Yellowstone National Park region, even considering climate change and the lack of lynx in those areas now.

Using a model validated by historic records, researchers first found that in 1900, Canada lynx had more suitable habitat in the U.S. than the few northern corners of the country where they are found currently. The study showed the elusive big cat likely roamed over a larger area in the Pacific Northwest, Rocky Mountains, Great Lakes region and parts of New England.

“History matters even for wildlife,” said lead author Dan Thornton, a Washington State University wildlife ecologist. “As part of the criteria for species recovery, we have to understand their historic distribution. Otherwise, how can we help recover a species, if we don’t know what we’re recovering to?”

Having a more accurate picture of a species’ past can also help avoid an effect known as “shifting baseline syndrome,” Thornton added, which is a gradual change in what people accept as normal for the environment, or specifically in this case, a species’ habitat.

Rice biologists uncover new species of tiger beetle: Eunota houstoniana

Eunota houstoniana, with male on left and female on right.
Photo Credit: Rice University

Rice University evolutionary biologist Scott Egan and his research team have unearthed a new species of tiger beetle, deemed Eunota houstoniana, honoring the Houston region where it predominantly resides.

The team employed cutting-edge genetic sequencing technology alongside traditional measurements of their physical appearance and geographic range data to redefine species boundaries within the Eunota circumpicta species complex. This approach, known as integrative taxonomy, allowed them to identify distinct biological entities previously overlooked.

The study is published online in Nature Scientific Reports.

“It is amazing that within the city limits of Houston, we still don’t know all the species of insects or plants we share our region with,” Egan said. “I’m always interested in learning more about the biodiversity of the Gulf Coast.”

The Eunota houstoniana was once considered synonymous with the more common Eunota circumpicta, but the team’s research revealed significant differences, emphasizing the need for a refined process to species delineation.

Eunota houstoniana exhibits distinct genetic and physical characteristics. It is slightly smaller in size, its metallic coloring is more subdued, and it has unique behavior and habitat preferences.

New rapid method to predict effects of conservation actions on complex ecosystems

From left: Dr Matthew Adams, Sarah Vollert, Professor Drovandi
Photo Credit: Courtesy of Queensland University of Technology

A new way to analyze the effects of conservation actions on complex ecosystems has cut the modelling time from 108 days to six hours, QUT statisticians have found:

• Some conservation efforts backfire, eg eradicating feral cats could lead to rabbit explosion

• Modeling predicts the cascading effects through species in a complex ecosystem, but is computationally slow

• New method cuts prediction time from 3.5 months to six hours

PhD researcher Sarah Vollert, from the School of Mathematical Sciences and the QUT Centre for Data Sciences, said it was impossible to predict exactly how conservation actions would affect each species.

“Though well-intentioned, conservation actions have the potential to backfire,” Ms. Vollert said.

“For example, if decision-makers decide to eradicate feral cats, it could lead to explosive populations of their prey species, like rabbits.

“Uncontrolled rabbit populations could then have devastating effects on the vegetation, destroying the habitat native species need to survive.

Honey bees at risk for colony collapse from longer, warmer fall seasons

WSU researchers and students collect samples and perform honey bee colony health assessments in orchards near Modesto, CA.
Photo Credit: Brandon Hopkins

The famous work ethic of honey bees might spell disaster for these busy crop pollinators as the climate warms, new research indicates.

Flying shortens the lives of bees, and worker honey bees will fly to find flowers whenever the weather is right, regardless of how much honey is already in the hive. Using climate and bee population models, researchers found that increasingly long autumns with good flying weather for bees raises the likelihood of colony collapse in the spring.

The study, published in the journal Scientific Reports, focused on the Pacific Northwest but holds implications for hives across the U.S. The researchers also modeled a promising mitigation: putting colonies into indoor cold storage, so honey bees will cluster in their hive before too many workers wear out.

“This is a case where a small amount of warming, even in the near future, will make a big impact on honey bees,” said lead author Kirti Rajagopalan, a Washington State University climate researcher. “It’s not like this is something that can be expected 80 years from now. It is a more immediate impact that needs to be planned for.”

Bees need food up to a month earlier than provided by recommended pollinator plants

Buff-tailed bumblebee (Bombus terrestris).
Photo Credit Matthias Becher

New research from the Universities of Oxford and Exeter has revealed that plant species recommended as “pollinator friendly” * in Europe begin flowering up to a month too late in the spring to effectively contribute to bee conservation.

This “hungry gap” results in low colony survival and low production of queens for the following year.

The results showed that pollen and nectar availability during the early colony founding stage is a critical, and previously under-appreciated, factor in bee colony success. **

The study has been published in the journal Insect Conservation and Diversity. 

Senior author Dr Tonya Lander (Department of Biology, University of Oxford) said: “The results give us a simple and practical recommendation to help bees: to enhance hedgerows with early blooming species, especially ground ivy, red dead-nettle, maple, cherry, hawthorn, and willow, which improved colony success rate from 35% to 100%. This approach focuses on existing hedgerows in agricultural land and doesn’t reduce farm cropping area, so can appeal to land managers whilst also providing important conservation outcomes for pollinators.” 

These were assessed using the BEE-STEWARD model, which integrates data and runs simulations to predict how changes in different factors may impact bee populations over time.

Rainforest’s next generation of trees threatened 30 years after logging

Logged forests have reduced seedling density, reducing the probability for the next generation to emerge.
Photo Credit David Bartholomew

Rainforest seedlings are more likely to survive in natural forests than in places where logging has happened – even if tree restoration projects have taken place, new research shows.

Scientists monitored over 5,000 seedlings for a year and a half in North Borneo.

They studied a landscape containing both natural forest and areas logged 30 years ago – some of which were recovering naturally, while some had been restored by methods including tree planting.

A drought had triggered “mast fruiting” across the region, with trees simultaneously dropping fruit en masse and new seedlings emerging.

At first, both natural forest and restored forest had similarly high numbers of seedlings, compared to naturally recovering forest – suggesting restoration activities enhanced fruit production.

But these benefits did not last: low seedling survival in the restored forest meant that, by the end of the study, similarly low numbers of seedlings remained in restored and naturally recovering forest. Seedling populations remained higher in natural forests.

Together, these results show that regeneration may be challenged by different factors depending on the restoration approach – seed availability in naturally recovering sites and seedling survival in sites where planted trees have matured. These differences may have longer-term implications for how forests can deliver key ecosystem services such as carbon sequestration.

Researchers discover a coral superhighway in the Indian Ocean

A coral reef in the Seychelles.
Photo Credit: Christophe Mason-Parker

Despite being scattered across more than a million square kilometers, new research has revealed that remote coral reefs across the Seychelles are closely related. Using genetic analyses and oceanographic modelling, researchers at Oxford University demonstrated for the first time that a network of ocean currents scatter significant numbers of larvae between these distant islands, acting as a ‘coral superhighway.’ These results have been published today in Nature Scientific Reports.

"This study couldn’t come at a timelier moment. The world is once again watching, as El Niño devastates coral reefs throughout the Indian Ocean. Now we know which reefs will be crucial to coral recovery, but we can’t pause in our commitment to reducing greenhouse gas emissions and stopping climate change."
Senior author of the study, Professor Lindsay Turnbull 
Department of Biology, University of Oxford

Dr April Burt (Department of Biology, University of Oxford, and Seychelles Islands Foundation), lead author of the study, said: ‘This discovery is very important because a key factor in coral reef recovery is larval supply. Although corals have declined alarmingly across the world due to climate change and a number of other factors, actions can be taken at local and national scale to improve reef health and resilience. These actions can be more effective when we better understand the connectivity between coral reefs by, for instance, prioritizing conservation efforts around coral reefs that act as major larval sources to support regional reef resilience.’

Halloween toy among plastics swallowed by sea turtles

A rubber witches' finger found inside a dead sea turtle.
Photo Credit: University-of-Exeter

A Halloween toy was among hundreds of plastic items found in the guts of dead sea turtles in the Mediterranean, a new study reveals.

Researchers examined 135 loggerhead turtles either washed up or killed as “bycatch” (accidentally caught) in fishing nets off northern Cyprus.

More than 40% of the turtles contained “macroplastics” (pieces larger than 5mm), including bottle tops and the Halloween toy – a rubber witch’s finger.

The research team, led by the University of Exeter and the North Cyprus Society for the Protection of Turtles (SPOT), say loggerheads are a potential “bioindicator” species that could help them understand the scale and impact of plastic pollution.

“The journey of that Halloween toy – from a child’s costume to the inside of a sea turtle – is a fascinating glimpse into the life cycle of plastic,” said Dr Emily Duncan, from Centre for Ecology and Conservation on Exeter’s Penryn Campus in Cornwall.

“These turtles feed on gelatinous prey such as jellyfish and seabed prey such as crustaceans, and it’s easy to see how this item might have looked like a crab claw.”

Loss of nature costs more than previously estimated

Photo Credit: Christian Heitz

Researchers propose that governments apply a new method for calculating the benefits that arise from conserving biodiversity and nature for future generations.

The method can be used by governments in cost-benefit analyses for public infrastructure projects, in which the loss of animal and plant species and ‘ecosystem services’ – such as filtering air or water, pollinating crops or the recreational value of a space – are converted into a current monetary value.

This process is designed to make biodiversity loss and the benefits of nature conservation more visible in political decision-making.

However, the international research team says current methods for calculating the values of ecosystem services “fall short” and have devised a new approach, which they believe could easily be deployed in Treasury analysis underpinning future Budget statements.

Their approach, published in the journal Science, takes into consideration the increase in monetary value of nature over time as human income increases, as well as the likely deterioration in biodiversity, making it more of a scarce resource.

Improving Wood Products Could Be a Key to Reducing Greenhouse Gas Emissions

Corrugated cardboard boxes are one of the most important products made from loblolly pine
Photo Credit: Aleksandar Pasaric

Harnessing the ability of wood products to store carbon even after harvest could have a significant effect on greenhouse gas emissions and change commonly accepted forestry practices, a new study from NC State researchers suggests.

The new study published in the journal Carbon Balance and Management uses carbon storage modeling to link the carbon stored in wood products with the specific forest system from which the products originated. Wood products and the forests they come from store different amounts of carbon, and being able to compare the two more specifically would help forest managers better understand these tradeoffs and plan for better carbon storage.

By tracing carbon in southern loblolly pine plantations from planting to harvest, the study also identified specific wood products that are important to improving carbon storage and reducing greenhouse gas emissions. Chief among them were corrugated carboard boxes.

“Corrugated cardboard boxes are one of the most important products made from loblolly pine,” said Sarah Puls, NC State graduate assistant and corresponding author of the study. “If we can extend the effective lifetime of products like these boxes, it could have a significant impact on the carbon storage associated with southern loblolly pine plantations.”

Aerial surveys reveal ample populations of rays in southeast Florida

The giant manta ray is designated as threatened under the U.S. Endangered Species Act and is protected in Florida waters.
Photo Credit: Steve Kajiura, Florida Atlantic University

The whitespotted eagle ray (Aetobatus narinari) and the giant manta ray (Mobula birostris) are rapidly declining globally. Both species are classified by the International Union for Conservation of Nature as endangered worldwide and the giant manta ray is designated as threatened under the United States Endangered Species Act.

In Florida waters, giant manta rays and whitespotted eagle rays are protected species. To provide effective management for these species, it is necessary to gather information on their distribution and abundance.

Using aerial surveys, Florida Atlantic University researchers conducted a unique long-term (2014 to 2021) study to quantify the spatial (latitude) and temporal (month, year) abundance of the whitespotted eagle rays and giant manta rays in Southeast Florida. The researchers conducted 120 survey flights between January 2014 and December 2021 along the Atlantic Coast from Miami north to the Jupiter Inlet. They reviewed the video footage from the flights to quantify the number of rays of each species.

New study uncovers the importance of deepwater ecosystems for endangered species

Hawksbills typically forage on coral reefs where their diet is predominantly sponges.
Photo Credit: Jeanne A Mortimer

Using tracking data, a new study has revealed for the first time that hawksbill turtles feed at reef sites much deeper than previously thought.

Critically endangered hawksbill turtles are found in every ocean and are the most tropical of sea turtles. Adult hawksbills have long been considered to have a close association with shallow (less than 15 meters depth) seas where coral reefs thrive.

Young hawksbills drift in currents during their open water phase of their development before they move to seabed habitats. Hawksbills are usually seen foraging in coral reefs where their diet is predominantly sponges.

To study their feeding habits in more detail, researchers at Swansea, Florida and Deakin universities used high-accuracy GPS satellite tags to track 22 adult female hawksbills from their nesting site on Diego Garcia in the Chagos archipelago in the Indian Ocean to their foraging grounds.

Scientists assemble a richer picture of the plight and resilience of the foothill yellow-legged frog

Foothill yellow-legged frogs live in the flowing water of rivers and streams, so are especially vulnerable when these shrink to isolated pools.
Photo Credit: Brome McCreary / USGS

Up to only a few inches in length, with a lemon-hued belly, the foothill yellow-legged frog may seem unassuming. But its range once stretched from central Oregon to Baja California. In 2023, it was listed under the federal Endangered Species Act. Its rapidly decreasing range is due in part to a fungal pathogen called Batrachochytrium dendrobatidis, or Bd, that has devastated amphibians around the world.

A team of researchers, including UC Santa Barbara’s Andrea Adams, has conducted the most comprehensive study to date of disease dynamics in foothill yellow-legged frogs. The team’s data — sourced from both wild frogs and specimens in museum collections — enabled them to track patterns of infection across a large geographic range. In a study published in Royal Society Open Science, the researchers reveal that drought, rising temperatures and the increasing conversion of land for agriculture appear to be the largest factors driving Bd infection in this species.

The researchers aimed to assemble as much data as they could, both in space and time. They surveyed in the creeks and rivers of California and Oregon, where they swabbed wild yellow-legged frogs for the presence of Bd. It also led them into fluorescent-lit museum collections to sample specimens from as far back as the 1890s.