The tool is described in a study published in the journal Ecological Applications by researchers from the University of California, Davis; U.S. Geological Survey (USGS), Cal Fire and the U.S. Forest Service.

“Huge fires are converting forested areas to landscapes devoid of living trees,” said lead author Joseph Stewart, a postdoctoral researcher at UC Davis and with USGS. “Managers need timely and accurate information on where reforestation efforts are needed most.”

The tool, also known as the Post-fire Spatial Conifer Regeneration Prediction Tool (POSCRPT), helps forest managers identify within weeks after a fire where sufficient natural tree regeneration is likely and where artificial planting of seedlings may be necessary to restore the most vulnerable areas of the forest.

NOT SO EVERGREEN

Conifers, or plants with cones such as pine trees, dominate many forests in western North America. The study found that conifers are less likely to regenerate after fires when seedlings face drier climate conditions, especially in low-elevation forests that already experience frequent drought stress. Overall, fewer conifers are expected to grow in California’s lower elevations following wildfire due to climate and drought conditions.

“We found that when forest fires are followed by drought, tree seedlings have a harder time, and the forest is less likely to come back,” said Stewart.

A UC Davis team collected post-fire recovery data from more than 1,200 study plots in 19 wildfires that burned between 2004 and 2012, as well as 18 years of forest seed production data. Ecologists at USGS collected and identified over 170,000 seeds from hundreds of seed traps. The scientists combined these data with multispectral satellite imagery, forest structure maps, climate and other environmental data to create spatial models of seed availability and regeneration probability for different groups of conifers, including pines and firs.

Forest managers have used a prototype of the tool in recent years to better understand where to focus regeneration efforts. The new upgrade incorporates information on post-fire climate and seed production and includes an easy-to-use web interface expected to increase the tool’s accuracy and use.

“This work is a great example of how multiple partners can come together to solve major resource management problems that are arising from California’s climate and fire trends,” said co-author Hugh Safford, regional ecologist for the USDA Forest Service’s Pacific Southwest Region and a member of the research faculty at UC Davis.

The study was funded by the USGS’ Southwest Climate Adaptation Science Center, Ecosystems Mission Area and Land Change Science Program.

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Materials provided by University of California – Davis. Original written by Kat Kerlin. Note: Content may be edited for style and length.

The Zika virus is primarily transmitted by the bite of an infected mosquito from the Aedes genus. However, it can also be passed through sexual contact, blood transfusions, organ transplants, and between mother and baby during pregnancy. The virus has been documented to cause a range of birth defects, including microcephaly and various neurological, musculoskeletal, and eye abnormalities.

A new study from Glenn Yiu, associate professor in the Department of Ophthalmology, and Koen Van Rompay, a core scientist at the California National Primate Research Center, found that Zika infection during the first trimester of pregnancy can impact fetal retinal development and cause congenital ocular anomalies. The virus does not appear to affect ocular growth postnatally, however.

“It has been known that congenital infection with the Zika virus can lead to eye defects, but it was unclear if the virus continues to replicate or affect eye development after birth,” Yiu said. “Our study in rhesus monkeys suggest that the virus primarily affects fetal development during pregnancy, but not the growth of eye after birth.”

In this collaboration between the UC Davis Eye Center and the California National Primate Research Center, two pregnant rhesus monkeys were infected with Zika virus late in the first trimester. The ocular development of the Zika-exposed infants was then studied for two years following their birth.

Ocular birth defects

The Zika-exposed infant monkeys did not display microcephaly or apparent neurological or behavioral deficits. The infants did exhibit several ocular birth defects, however. The defects included large colobomas, a missing gap in the eye due to abnormal development. The Zika-exposed infant monkeys also exhibited a loss of photoreceptors — the light-sensing cells of the retina — and retinal ganglion neuron, which helps transmit visual information to the brain.

Despite congenital ocular malformations at birth, their eyes appeared to follow normal development during their first two years.

The findings suggest that ocular defects due to Zika infection primarily occur in utero and likely do not have a continued impact on ocular development after birth.

Rhesus macaques are natural hosts of the virus and share similar immune and ocular characteristics to humans, including blood-retinal barrier characteristics and the unique presence of a macula, making them superior animal models of the infection than typical laboratory animals like mice and rats. The findings were published in JCI Insight, an open-access peer-reviewed journal dedicated to biomedical research.

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Materials provided by University of California – Davis. Original written by Lisa Howard. Note: Content may be edited for style and length.

Assistant professor Kristian Forbes, along with colleagues from Africa, Europe and North America, have proposed a four-part approach to detect and contain zoonotic diseases, those that begin in animals but spillover into humans, like COVID-19 and HIV.

“A lot of research effort to prepare against the threat of novel disease emergences of wildlife viruses has been to identify unknown viruses in wildlife that might someday infect humans,” Forbes said. “These efforts have been very successful for identifying new viruses; indeed, thousands have been discovered, but we don’t currently have the tools to know which of them pose the most immediate risks to human health.”

To enable fast detection of new zoonotic disease outbreaks, the team proposes a system of procuring and screening samples from hospital patients with fevers of unknown origin, analyzing samples from suspicious fatalities of unknown cause, testing blood serum in high-risk or sentinel groups and analyzing samples that have already been collected and archived. The team outlined their approach in a recent article published in the journal The Lancet Microbe.

None of these methods are new, Forbes said. But to date they have not been combined into a continent-wide program aimed at rapid detection.

“Given limitations to the current model for preventing disease emergences, our article focuses on a coordinated and widespread strategy for early detection so that novel disease outbreaks can be intercepted before they potentially become global pandemics.”

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Materials provided by University of Arkansas. Note: Content may be edited for style and length.

A shark-like ray, smalltooth sawfish (Pristis pectinata) are unique for their long flat rostra with roughly 22-29 teeth on either side that is used to detect and catch prey. The species can reach 16-feet in length. NOAA estimates that smalltooth sawfish populations in U.S. waters have declined by as much as 95 percent from a combination of overfishing, bycatch in fishing gear, and habitat loss from increasing coastal development.

The research team compiled sighting records dating as far back as 1895 and recent encounters of sawfish in the Biscayne Bay Habitat Focus Area.

“Our analysis showed sightings have increased exponentially in recent decades, with some individuals even appearing to be making returning annual visits,” said Laura McDonnell, the study’s lead author and a PhD student at UM Abess Center for Ecosystem Science & Policy and researcher at the UM Rosenstiel School. “These findings demonstrate that smalltooth sawfish have been using these waters with some regularity, largely unnoticed prior to the compilation of these records.

“However, the extent to which sawfish use Biscayne Bay and reason for their occurrence remains unknown,” said Joan Browder, a fisheries biologist at NOAA’s Southeast Fisheries Science Center and senior author of the study. “Understanding this would be a valuable next research step.”

Many of the smalltooth sawfish documented in this study were found in waters very close to Miami, where they were exposed to high levels of pollution, boat traffic, and fishing.

“These results highlight a need to understand the effects of coastal urbanization on smalltooth sawfish and the conservation implications for this and other endangered species using the area,” said Neil Hammerschlag, research associate professor at the UM Rosenstiel School and UM Abess Center for Ecosystem Science & Policy and co-author of the study.

“Given the documented use of smalltooth sawfish in and around Biscayne Bay, we hope the area will receive informative signage to help inform the public about their endangered status, the importance of reporting encounters, and the dangers of harming sawfish,” said McDonnell.

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Materials provided by University of Miami Rosenstiel School of Marine & Atmospheric Science. Original written by Diana Udel. Note: Content may be edited for style and length.

However, novel organisms moving into a new habitat could disturb the ecological balance which has been established over a long period. Plants and herbivores are characterised by long-term co-evolution, shaping both their geographic distribution and the characteristics that they display in their occupied sites.

At higher elevations, this is seen in insect herbivores being generally less abundant and plants in turn being less well defended against herbivores, as a result of lower energy and shorter growing seasons. In contrast, low-elevation plant species defend themselves against more abundant and diverse herbivores, whether by means of spikes, thorns or hair, or by toxic substances. Climate change could disturb this ecological organisation.

Grasshoppers translocated to high elevations

In an experiment, researchers from ETH Zurich, the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) and the University of Neuchâtel investigated what could happen if herbivores — in this case various grasshoppers from middle elevations — settled in alpine meadows at higher elevations and encountered new plant communities there. The study has just been published in the journal Science.

The researchers translocated various grasshopper species from medium altitudes (1,400 metres above sea level) to three alpine grassland sites at elevations of 1,800, 2,070 and 2,270 metres above sea level, where the ecologists placed the grasshoppers in cages. The local grasshoppers had previously been removed from the experimental areas. The experiment was carried out in the Anzeindaz region in the Vaud Alps, Switzerland.

In their study, the researchers measured things like how the biomass, structure and composition of the alpine plant communities changed under the influence of the herbivorous insects. The researchers also investigated whether some plant species were more susceptible to herbivory, for instance plants with tougher leaves, or those containing more silica or other constituents such as phenols or tannins.

Lowland grasshoppers influence alpine community

The ecologists discovered that the grasshoppers’ feeding behaviour had a clear influence on the vegetation structure and composition of the alpine flora. Alpine communities display clear structure in the organisation of the canopy, with plants with tough leaves at the top, and more shade-tolerant plants with softer leaves at the bottom. But this natural organisation was disturbed, because the translocated grasshoppers preferred to feed on taller and tough alpine plants, which exhibited functional characteristics such as leaf structure, nutrient content, chemical defence, or growth form similar to those of their previous, lower-elevation food plants. As a result, the insects reduced the biomass of dominant tough alpine plants, which in turn favoured the growth of small-stature plant species that herbivores avoid. The overall plant diversity thus increased in the short term.

“Immigrant herbivores consume specific plants in their new location and this changes and reorganises the competitive interaction between those alpine plant species,” says the study’s first author, Patrice Descombes. Global warming, for example, could disrupt the ecological balance because mobile animals, including many herbivorous insects, can expand their habitat to higher elevations more rapidly than sedentary plants. Herbivorous insects from lower altitudes could therefore have an easy time in alpine habitats with resident plants that are insufficiently or not at all prepared to defend themselves against those new herbivores. This could change the current structure and functioning of alpine plant communities as a whole. Climate change would thus have an indirect impact on ecosystems, in addition to the direct consequences of rising temperatures.

Important drivers of changed ecosystems

For Loïc Pellisier, Professor of Landscape Ecology at ETH Zurich and WSL, this indirect effect of climate change on ecosystems is one of the most important things to emerge from the study: “Climate impact research has largely investigated the direct effects of temperature on ecosystems, but these novel interactions that arise between species moving into new habitats could generate important structural modifications. They are important drivers of changed ecosystems in an increasingly warm climate.”

With their results, the researchers also want to improve models that have so far only inadequately integrated such processes. They also hope that this will improve the prognosis of how climate change will influence the functioning of ecosystems and the services they provide.

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Materials provided by ETH Zurich. Original written by Peter Rüegg. Note: Content may be edited for style and length.