Xylophaga lobata

Plant growth in arid <a href="https://www.earth.com/news/mangrove-forest-reveals-ancient-climate-change-effects/">mangroves</a> is often limited by a lack of precipitation, poor nutrient availability, and high soil salinity. Soil bacteria play a crucial role in processes that sustain plant growth, such as transforming dead vegetation into useful nutrients. However, regardless of its importance for the health of mangrove habitats, the sediment microbiome of these ecosystems has been largely overlooked in previous scientific studies.&nbsp;



Now, a research team led by the <a href="https://www.kaust.edu.sa/">King Abdullah University of Science &amp; Technology</a> (KAUST) in Saudi Arabia has found that fiddler crabs burrowing beneath arid mangrove forests help bring beneficial bacteria to ecosystems in dire need of nutrients.



&nbsp;“Mangroves are the most efficient ecosystem in the world at absorbing carbon dioxide and therefore fighting climate change,” said study lead author Marco Fusi, a marine scientist at KAUST. However, since global warming puts increasing pressure on these already vulnerable ecosystems, Fusi and his colleagues embarked on a quest to understand how their resilience could be improved.



The scientists investigated whether soil disturbance, or “bioturbation” by fiddler crabs affects the sediment microbiome and consequently plant growth&nbsp;in an arid mangrove ecosystem on the Red Sea. “The rationale behind this research is that the continuous soil reworking by the ‘animal engineers’ creates an ‘oxygenation halo’ around the burrows, which makes the sediment more hospitable to bacteria that, in turn, help the plant with nutrients,” explained study senior author Daniele Daffonchio, a professor of Marine Science at KAUST.



By analyzing ten plots isolated by fences, with five of them containing extra crabs brought in from nearby mangroves, the researchers found that the enriched plots contained more beneficial bacteria, including several&nbsp;Gammaproteobacteria&nbsp;and&nbsp;Alphaproteobacteria&nbsp;which&nbsp;produce chemicals essential for trapping iron in the sediment. Since Red Sea mangroves are iron deficient, bacteria that help deliver iron to the trees can significantly improve their growth.



Moreover, increased fiddler crab activity also improved soil pH and salinity. “We found a strong effect of bioturbation on soil pH and salinity,” said Fusi. “In some cases, bioturbation can reduce salinity, thereby alleviating the salt stress on the plant.”&nbsp;&nbsp;&nbsp;



In future research, the scientists aim to assess whether bioturbation can also impact the settling and growth of mangrove seedlings. According to Fusi, “understanding how bioturbation affects the microbial community is extremely important to drive nature-based solutions to protect, restore and conserve mangroves.”&nbsp;



“Our findings suggest that maintaining conditions that favor fiddler crabs could help arid mangroves thrive under changes imposed by global warming,” concluded co-author Jenny Booth, a marine microbiologist at KAUST.



The study is published in the journal <a href="http://dx.doi.org/10.1128/spectrum.01117-22">Microbiology Spectrum</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer&nbsp;&nbsp;

Burrowing crabs bring beneficial bacteria to mangrove forests

Plant growth in arid mangroves is often limited by a...

Southern,Right,Whale,With,Gull

Southern right whales (Eubalaena australis) are native to oceans in the southern hemisphere and a breeding population exists around Aotearoa New Zealand and its sub-Antarctic <a href="https://www.earth.com/news/what-types-of-islands-attract-migratory-birds/">islands</a>. The whales, known locally as tohorā, used to be more common in the region, and are known to have come inshore in the past to use sheltered harbors for calving and mating. The large numbers that were present in earlier times were dramatically reduced by whaling activity and by the time the killing of this species was banned in 1937, southern right whales were almost extinct, globally.&nbsp;



As a result of the hunting, there was no sighting of a southern right whale for 35 years in the waters around mainland Aotearoa New Zealand, with the remnant population persisting only around the remote sub-Antarctic islands. However, by 2009 there were an estimated 2,200 of these whales in the region, indicating a slow but steady recovery in the population. Individuals move between mainland Aotearoa New Zealand, including Stewart Island (Rakiura), and the sub-Antarctic Auckland Islands (Maungahuka) and Campbell Island (Motu Ihupuku). Sightings are still very rare and may number no more than one or two in total, in some years.&nbsp;



A new study, led by Annabelle Cranswick of the <a href="https://www.auckland.ac.nz/en.html">University of Auckland</a>, has made use of posts on Facebook and nature-watching network iNaturalist to bolster the data on whale sightings and help monitor the population of southern right whales in Aotearoa New Zealand waters.&nbsp;



By using sightings data from 2011 to 2021 recorded in the New Zealand Department of Conservation's <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/marine-mammal">Marine Mammal</a>&nbsp;Database, and supplementing these with crowd-sourced sightings reported on Facebook and iNaturalist, the researchers were able to increase the spatiotemporal extent of sampling for this rare and whale species.



“Photos supplied on social media and by citizen scientists are proving so important for us to monitor populations of these recovering whales,” said Cranswick. “We can assess that yes, this is a southern right whale, and discover how long a whale stayed in a particular area. “Even a distant photo, showing just part of a whale, can be helpful,” says Cranswick. “We can pick a southern right from just the white patches called callosities on the head, their flat back which lacks a dorsal fin, or even their large paddle-shaped pectoral fins.”&nbsp;&nbsp;



In total, there were only 116 sightings of southern right whales in New Zealand waters from both the Department of Conservation and the social network sources, reported over the 11-year research period (2011–2021). Since all the social media sightings were accompanied by photos that enabled species identification, these posts increased the overall number and quality of sightings and provided new information on the fine-scale movement and residency times of the whales.&nbsp;



“We went through ten years of social media data to extract these sighting reports,” said Hannah Hendriks, a marine biologist with the Department of Conservation. “There are very few whale researchers and rangers scattered across the country, so we rely on the public to be our eyes and ears.”



Bobby Phuong, a mailman in Christchurch who’s an enthusiastic amateur wildlife photographer, shot one of the images to feature in the study. He drove for nearly an hour to see a whale and calf at Sumner in August last year, sharing his photos via Facebook. “They were remarkable to witness and I’m glad my photos have helped in some way,” he says. In Gisborne, Wainui Beach resident Ian Ruru captured images of a southern right whale frolicking in the waves, meters away from surfers, in September 2018. “She sat directly in front of our home for eight hours that day … I guess she wanted her story to be told ... Paikea we called her,” said Ruru.



The results of the analysis, published in the journal <a href="https://www.sciencedirect.com/journal/ocean-and-coastal-management">Ocean &amp; Coastal Management</a>, indicate that, although numbers of whales have increased slowly in the region during the study period, the numbers around mainland New Zealand have not grown in the past decade. The authors hypothesize that this may due to the loss of so many female whales during the time of whaling, that the collective memory about making use of the mainland waters has been lost.&nbsp;



This study highlights the way in which social media may be put to good use to supplement knowledge and data gaps in traditional ecological monitoring programs. Whales are charismatic megafauna that often appear on social network posts and are ideal for public outreach sightings data.&nbsp;



“Social media provided detailed information from areas with lots of people and lots of cameras,” said study co-author Dr. Emma Carroll. “Where there are fewer people, like the west coast of Te Waipounamu (the South Island), information from the public and Department of Conservation rangers recorded in the national database was more important,” she explained.



The researchers stress that, although photographs and sightings of inshore whales are invaluable sources of important data, would-be citizen-scientists are reminded that photographers must stay 50m from adult whales and 200m from whales with calves, so as not to disturb them.&nbsp;



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By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Social media posts help monitor rarely sighted whales

Southern right whales (Eubalaena australis) are native to oceans in...

Scientists are finding an ecological and economic balance between <a href="https://www.earth.com/news/biodiversity-loss-weakens-ecosystem-functioning/">biodiversity</a> and vanilla cultivation in Madagascar. A team of researchers led by the <a href="https://www.uni-goettingen.de/en/1.html">University of Göttingen</a> has found a way to cultivate a cash crop while preserving biodiversity in Madagascar.&nbsp;



Although the vanilla industry in Madagascar brings positive and negative outcomes to the local Malagasy, it cannot be denied that the enterprise is a significant source of income for those fortunate enough to have the land to grow vanilla and resources to protect it.



"In northeastern Madagascar, the export of vanilla is an important source of income for tens of thousands of smallholder farmers and the widespread cultivation is a way to escape from poverty," explained study first author Dr. Annemarie Wurz.



The research team found vanilla cultivated on fallow land (agricultural land left unworked for some time) was better for biodiversity than vanilla cultivated in forests. For example, the experts found that vanilla grown in the forest led to a 47 percent decrease in endemic species. This number is depressing, especially considering that Madagascar is known for its unique species.&nbsp;



The study, published in the journal <a href="http://www.nature.com/articles/s41467-022-30866-8">Nature Communications</a>, was focused on biodiversity in Madagascar's northeastern area, a region known to be the world's largest vanilla producer. Wildlife examined for the study included trees, herbaceous plants, birds, amphibians, reptiles, butterflies, and ants.



The researchers discovered that growing vanilla on fallow land does not sacrifice economic gain since fallow land production and forest cultivation produce similar yields.



"The good news is that farmers do not have to clear land to achieve high yields. In fact, they can add value for biodiversity to fallow land by cultivating vanilla there," said Dr. Annemarie Wurz.



However, it should be noted that the density and length of the vanilla plants themselves could harm some aspects of biodiversity. The study found that denser and longer plants were better for crop yields but harmed tree and reptile species.



Nevertheless, the findings of this study could be crucial in conserving the biodiversity and economy of this delicate country.&nbsp;



"Promoting vanilla cultivation on fallow land is ecologically and economically significant," said study co-author Professor Ingo Grass. "This contributes to the current UN Decade for Ecosystem Restoration. In addition, this study illustrates possibilities for promoting and conserving biodiversity outside protected areas."



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By <a href="mailto:nire518@gmail.com">Erin Moody </a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Vanilla cultivation can boost biodiversity in Madagascar

Scientists are finding an ecological and economic balance between biodiversity...

On the eve of <a href="https://worldelephantday.org/">World Elephant Day</a> (August 12), an analysis of social media posts led by <a href="https://www.griffith.edu.au/">Griffith University</a> in Australia has highlighted how the type of attention <a href="https://www.earth.com/news/elephants-have-personality-traits-that-help-them-solve-problems/">elephants</a> receive on Twitter does not align with the most pressing threats to wild elephants. This phenomenon may have negative consequences for elephant conservation and lead to resentment from the local communities that live with elephants.&nbsp;



According to the <a href="https://www.iucn.org/">International Union for Conservation of Nature</a> (IUCN), the most pressing threats elephants currently face are habitat loss, human-elephant conflict, and poaching, with the magnitude of each threat varying between the three species of elephants (the African Forest Elephant, the African Savanna Elephant, and the Asian Elephant).&nbsp;



“The key highlights were that of the three main threats to wild elephants – being poached, habitat loss, and human-elephant conflict – there was a lack of attention on Twitter specifically around habitat loss and human-elephant conflict,” said study lead author Niall Hammond, a doctoral student in Wildlife Conservation at the Griffith University.&nbsp;“Our Twitter analysis revealed these major threats were infrequently discussed, with habitat loss being the most infrequently discussed (less than one percent of all tweets).”



The analysis showed that the most frequently discussed aspects were elephant welfare issues, such as tourist elephant rides (23 percent). Users from non-elephant range regions were the dominant voice on Twitter (72 percent), with posts largely focusing on elephant welfare concerns and trophy hunting (which, in fact, is not a threat to elephant conservation). By contrast, users from African Elephant range countries (14 percent) were more likely to discuss human-elephant conflict and poaching, as well as to promote elephant tourism, while those from Asian Elephant range countries (13 percent) posted more about human-elephant conflict and elephant tourism, but were less likely to tweet about poaching.



“Human-elephant conflict is a major issue. Our study found that the lack of acknowledgement of the impact of human-elephant conflict on local people often leads to resentment from people within elephant range countries, where peoples’ safety and livelihoods are often at risk due to elephants. For example, in India it is estimated that 100 people are killed by elephants each year and 40-50 elephants are killed during crop raiding,” Hammond explained.



Thus, the location of the tweets’ origins highlighted a divide in the understanding and lived experience of those living in countries with elephants and those without. “When we watch nature documentaries, elephants are often portrayed as living in areas where there are no people, but that is not the reality.”



“The reality is that in many areas, elephants and people live in shared spaces, where there are no fences to separate people and wildlife. It is important to acknowledge the sacrifices these communities make on a daily basis in co-existing with elephants and advocate for greater rights for communities to manage their wildlife sustainably because without their continued support the conservation of elephants would not be possible,” he concluded.



The study is published in the journal <a href="http://dx.doi.org/10.1111/csp2.12785">Conservation Science and Practice</a>.&nbsp;



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer&nbsp;&nbsp;

Elephant tweets often misrepresent conservation issues

On the eve of World Elephant Day (August 12), an...

In many animals – and most <a href="https://www.earth.com/news/the-dinosaurs-died-in-the-springtime/">dinosaurs</a> – the eye sockets are circular holes in the skull housing the eyeballs. However, according to a new study led by Dr. Stephan Lautenschlager, a senior lecturer in Paleobiology at the <a href="https://www.birmingham.ac.uk/index.aspx">University of Birmingham</a>, large dinosaur predators, such as Tyrannosaurus Rex, evolved different, elliptical or oval shapes of eye sockets in order to better deal with forceful bites.



Dr. Lautenschlager analyzed the shape of the eye sockets of over 500 different dinosaurs and related species. “The results show that only some dinosaurs had eye sockets that were elliptical or keyhole-shaped,” he said. “However, all of those were large, carnivorous dinosaurs with skull lengths of one meter or more.”



By using computer simulations and stress analysis, Dr. Lautenschlager investigated what purpose such unusual eye socket shapes could have, and discovered that a skull with circular eye sockets was more prone to high stresses during biting. However, if these were replaced with elliptical or oval eye sockets, the stress during biting was considerably reduced, allowing major predators to evolve high bite sources that would not compromise their skull stability.



While most herbivorous dinosaur species and juvenile individuals retained circular eye socket shapes, large carnivores such as T. Rex adopted different morphologies, including elliptical, keyhole-shaped, of figure-of-eight-shaped sockets. “In these species, just the upper part of the eye socket was actually occupied by the eyeball. This also led to a relative reduction of eye size compared with skull size,” explained Dr. Lautenschlager.



“These morphologies are beneficial in mitigating and dissipating feeding-induced stresses and require only little investment in reinforcing the bony structure of the skull. Conversely, the development and maintenance of large circular orbits and corresponding eyes would be physiologically costly and likely outweigh potential benefits for visual acuity,” he concluded.



The study is published in the journal <a href="https://www.nature.com/articles/s42003-022-03706-0#Sec6">Nature Communications Biology</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer&nbsp;&nbsp;

Dinosaurs evolved different eye sockets for stronger bites

In many animals – and most dinosaurs – the eye...

Early days of the COVID-19 <a href="https://www.earth.com/news/pandemic-restrictions-had-a-lasting-effect-on-behavior-patterns/">pandemic</a> were a stressful time marked by fear, isolation, and uncertainty. But for birds, the reduction in noise and commotion created a wider range of habitat in cities.



A new study from the <a href="https://www.washington.edu/">University of Washington</a> reports that many birds were just as likely to be found in highly developed urban areas as they were in less-developed green spaces during COVID-19 lockdowns in the Pacific Northwest.



“Our findings suggest that some birds may have been able to use more spaces in cities because our human footprint was a little lighter,” said Olivia Sanderfoot, who completed the study as a doctoral researcher and is now a postdoctoral scholar in the Department of Ecology and Evolutionary Biology at the University of California, Los Angeles.&nbsp;



“For about half of the species we observed, neither land use nor canopy cover had an effect on their site use. That’s very interesting, because we would expect that whether a habitat was mostly covered in concrete or vegetation would tell you something about what birds would be there,” said Sanderfoot.



In the spring of 2020, more than 900 community scientists were recruited to participate in the study. The volunteers chose their own monitoring sites such as backyards and parks, and recorded the birds they observed at least once a week. This allowed researchers to gather data despite the lockdowns and gave many volunteers a welcomed distraction from the stresses of the pandemic.



Among the 35 species that showed the strongest changes in behavior were some of the Pacific Northwest’s most iconic, including chickadees, great blue herons, downy woodpeckers and Wilson’s warblers. The researchers focused on 46 bird species overall and completed more than 6,000 individual surveys.



To compare bird observations to human activity, the team used data from Google’s Community Mobility Reports, which track the relative amount that people moved around at various points during the pandemic.



As people returned to public spaces and human activity increased, volunteers recorded an increase in sightings of several bird species in green spaces. While the birds may have been elsewhere during lockdowns enjoying the absence of human disturbance, they returned to green spaces when activity picked up again.&nbsp;&nbsp;



“This could tell us how important it is to build green spaces into our cities. That’s the biggest takeaway for me.” said Sanderfoot.



The study is published in the journal <a href="https://www.nature.com/srep/">Scientific Reports</a>.



Image Credit: Holly Hauser



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By <a href="mailto:katherinebucko@gmail.com">Katherine Bucko</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Birds expanded into quieter cities during Covid lockdowns

Early days of the COVID-19 pandemic were a stressful time...

Every year, trillions of <a href="https://www.earth.com/news/pitcher-plants-harness-rain-energy-to-capture-insects/">insects</a> in Western Europe undertake seasonal migrations; usually they move southward towards the Mediterranean and North Africa at the end of the northern summer, and return northward during the spring or early summer. The same pathway is followed by many species of moths, butterflies and hoverflies; vast numbers of these insects cross the Alps in order to fly as directly as possible to their overwintering destinations.&nbsp;



Although these enormous migrations are understood on a population level, very little is known about how individual insects manage to navigate their way through the considerable obstacles, or what methods they use to locate their destinations. This gap in understanding is due, mostly, to the challenge of tracking these small animals as they fly, surprisingly rapidly and often at night.&nbsp;



A new study on migrating death’s-head hawkmoths (Acherontia atropos) has now used miniscule tracking devices and a light aircraft to track seven individual moths as they migrated across the Alps at night. The study, published by the <a href="https://www.aaas.org/">American Association for the Advancement of Science</a> (AAAS), reveals that these hawkmoths make use of complex migratory strategies to stay on track.&nbsp;



The death’s-head hawkmoth, known for the sinister skull-shaped marking on its thorax, is the largest lepidopteran in Europe, weighing in at up to 3.5g. It is a long-distance Afro-Palearctic migrant that arrives to breed in Europe, north of the Alps, in spring each year. The subsequent generation returns south the following autumn to winter-breeding regions in the Mediterranean Basin and sub-Saharan Africa, covering a distance of up to 4,000km.&nbsp;



The researchers fitted tiny, very high frequency radio transmitters to the backs of 14 hawkmoths and recorded their precise GPS locations from a light aircraft at regular intervals (every 5 to 15 min, when possible) throughout their migration. They obtained detailed tracks for seven of the moths. The moths all started their migratory flights shortly after sunset, and were followed by the researchers for between 1 and 3.7 hours. During this time, the moths flew a mean distance of 63.7km, with the longest distance being 89.6km. This represents the longest distance over which any insect has been continuously tracked in the field.



A team led by Dr. Myles Menz&nbsp;from the Max Planck Institute of Animal Behavior discovered that the moths did not just fly in a direction with favorable tailwinds, as had been proposed by other scientists in the past. Instead, the moths flew in the most direct straight line to their destination, but were able to correct their specific flight headings constantly, as they came across disruptive winds and specific features of the terrain.&nbsp;



The hawkmoths traveled at a mean ground speed of 33.8km/hour, and they all travelled in straight lines along their entire flight paths, which lasted tens of kilometers. This direct line was maintained, despite the presence of winds of varying strengths and directions throughout their course.&nbsp;&nbsp;



According to the researchers, maintaining a consistently straight flight trajectory and flight speed throughout the night under variable wind conditions strongly suggests that the moths have an internal compass mechanism. This, along with the insect’s exceptional night vision, indicates that the hawkmoths likely use a combination of visual landmarks and Earth’s magnetic field to navigate considerable distances during migration.



Interestingly enough, the moths chose pathways through the mountains that had topographical features (such as high-altitude passes) which allowed them to avoid the very highest altitudes when crossing the Alps. One of these pathways involved using a wide valley running west-southwest that enabled the moths to circumvent the Alps altogether.



The research, published in the journal <a href="https://www.science.org/">Science</a>, sheds new light on the complex and sophisticated behavior of hawkmoths while on seasonal migrations. "To maintain such straight trajectories over long periods of time, as seen here, the moths must regularly update their positions relative to whichever navigational cues they rely on," wrote the study authors. The results show that complex migratory strategies are not the preserve of vertebrates alone, but can be found in these remarkable insects as well.&nbsp;



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By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

How death’s-head hawkmoths navigate the Alps at night

Every year, trillions of insects in Western Europe undertake seasonal...

Xylophaga lobata

Taxonomic tree: