Wednesday, June 22, 2022

ECOCIDE

Dead rivers: The cost of Bangladesh's garment-driven economic boom

Industrial waste enters the Buriganga River as boatmen wait for passengers in Karanigonj
Industrial waste enters the Buriganga River as boatmen wait for passengers in Karanigonj.

Bangladeshi ferryman Kalu Molla began working on the Buriganga river before the patchwork of slums on its banks gave way to garment factories—and before its waters turned pitch black.

The 52-year-old has a constant cough, allergies and skin rashes, and doctors have told him the vile-smelling sludge that has also wiped out marine life in one of Dhaka's main waterways is to blame.

"Doctors told me to leave this job and leave the river. But how is that possible?" Molla told AFP near his home on the industrial outskirts of the capital Dhaka. "Ferrying people is my bread and butter."

In the half-century since a devastating independence war left its people facing starvation, Bangladesh has emerged as an often unheralded economic success story.

The South Asian country of 169 million has overtaken its neighbour India in per capita income and will soon graduate from the United Nations' list of the world's least developed countries.

Underpinning years of runaway growth is the booming garment trade, servicing global fast-fashion powerhouses, employing millions of women and accounting for around 80 percent of the country's $50 billion annual exports.

But environmentalists say the growth has come at an incalculable cost, with a toxic melange of dyes, tanning acids and other dangerous chemicals making their way into the water.

Bangladesh will soon graduate from the UN's list of the world's least developed countries, but environmentalists say the growth
Bangladesh will soon graduate from the UN's list of the world's least developed countries, 
but environmentalists say the growth has come at an incalculable cost.

Bangladesh's capital Dhaka was founded on the banks of the Buriganga more than 400 years ago by the Mughal empire.

"It is now the largest sewer of the country," said Sheikh Rokon, the head of the Riverine People environmental rights group.

"For centuries people built their homes on its banks to bask in the river breeze," he added. "Now the smell of toxic sludge during winter is so horrible that people have to hold their noses as they come near it."

Water samples from the river found chromium and cadmium levels over six times the World Health Organization's recommended maximums, according to a 2020 paper by the Bangladeshi government's River Research Institute.

Both elements are used in leather tanning and excessive exposure to either is extremely hazardous to human health: chromium is carcinogenic, and chronic cadmium exposure causes lung damage, kidney disease and premature births.

Ammonia, phenol and other byproducts of fabric dyeing have also helped to starve the river of the oxygen needed to sustain marine life.

Water samples from the Buriganga river found chromium and cadmium levels over six times the World Health Organization's recommen
Water samples from the Buriganga river found chromium and cadmium levels over six times
 the World Health Organization's recommended maximums.

'They are powerful people'

In Shyampur, one of several sprawling industrial districts around Dhaka, locals told AFP that at least 300 local factories were discharging untreated wastewater into the Buriganga river.

Residents say they have given up complaining about the putrid smell of the water, knowing that offending businesses are easily able to shirk responsibility.

"The factories bribe (authorities) to buy the silence of the regulators," said Chan Mia, who lives in the area.

"If someone wants (to) raise the issue to the factories, they'd beat them up. They are powerful people with connections."

The crucial position of the textile trade in the economy has created a nexus between business owners and the country's political establishment. In some cases, politicians themselves have become powerful industry players.

The Buriganga river is “now the largest sewer of the country," says Sheikh Rokon, the head of the Riverine People environme
The Buriganga river is “now the largest sewer of the country," says Sheikh Rokon, the
 head of the Riverine People environmental rights group.

Further south, in Narayanganj district, residents showed AFP a stream of crimson-coloured water draining into stagnant canals from a nearby factory.

"But you cannot say a word about it loudly," an area resident told AFP, speaking on condition of anonymity. "We only suffer in silence."

The Bangladesh Garment Manufacturers and Exporters Association (BGMEA), which represents the interests of around 3,500 top factories, defends its record by pointing out the environmental certifications given out to its members.

"We are going green—that's why we are witnessing big jumps in export orders," BGMEA president Faruque Hassan told a recent press conference.

But smaller factories and sub-contractors operating on the industry's razor thin margins say they are unable to afford the cost of wastewater treatment.

A top garment official in the Savar industrial district, speaking to AFP on condition of anonymity, said even most high-end factories serving major US and European brands often do not turn on their treatment machinery.

"Not everyone regularly uses it. They want to save costs," he said.

Bangladesh’s booming garment trade accounts for around 80% of the country's exports, but many factories are close to rivers with
Bangladesh’s booming garment trade accounts for around 80% of the country's exports, 
but many factories are close to rivers with a toxic melange of dyes, tanning acids and 
other dangerous chemicals making their way into the water.

'Facing the same fate'

Bangladesh is a delta country criss-crossed by more than 200 waterways, each of them connected to the mighty Ganges and Brahmatura rivers that course from the Himalayas and through the South Asian subcontinent.

More than a quarter of them are now heavily contaminated with industrial pollutants and need to be "urgently" saved, said an April legal notice sent to the government by the Bangladesh Environmental Lawyers Association (BELA).

Authorities have established a commission tasked with saving key water bodies, upon which close to half the country's population depend for farming, according to the UN Food and Agriculture Organization.

The National River Commission has launched several high profile drives to fine factories found to have polluted rivers.

Its newly appointed chief, Manjur Chowdhury, said "greedy" industrialists were to blame for the state of the country's waterways.

Any action will be too late for the five rivers that circle Dhaka and its industrial outskirts - all are already technically dea
Any action will be too late for the five rivers that circle Dhaka and its industrial outskirts - 
all are already technically dead, meaning they are completely devoid of marine life, said 
prominent environmental activist Sharif Jamil.

But he also admitted that the enforcement of existing penalties was inadequate to address the scale of the problem.

"We have to frame new laws to face this emergency situation. But it will take time," he told AFP.

Any action will be too late for the five rivers that circle Dhaka and its industrial outskirts.

All are already technically dead, meaning they are completely devoid of marine life, said prominent environmental activist Sharif Jamil.

"With factories now moving deep into the rural heartland, rivers across the country are facing the same fate," he told AFP.

Bangladesh factories ordered shut to save key river

© 2022 AFP




The freshwater pearl mussel favors the original salmon fish populations of the home river

The freshwater pearl mussel favors the original salmon fish populations of the home river
Salmon fry. Credit: Heidi Kunttu / University of Jyväskylä

Researchers at the University of Jyväskylä, Finland, have found that the larvae of freshwater pearl mussel survive best in the original salmon fish population of their home river. Their study was published in Freshwater Biology.

Freshwater pearl mussel larvae live as parasites on the gills of fish. The larvae grow and develop attached on the gills for 9 to 11 months, and then drop to the river bottom as tiny mussels.

"In our previous studies we have proved that the mussel larvae are able to attach only to the gills of the salmon or the trout, and that in big salmon  the best host for the mussel is the salmon and in smaller rivers the trout," says Professor Jouni Taskinen, Director of the Konnevesi Research Station of the University of Jyväskylä and the LIFE Revives project. "In this study we wanted to find out if the freshwater pearl mussels have adapted particularly to the salmon fish population of the home river."

In the study, salmon and trout rivers were compared by joining mussel larvae with fish species of the home river and other rivers. The experiments were made in rivers and brooks in Lapland, Northern Ostrobothnia and Kainuu.

The original host fish of the home river is the most welcome

The freshwater mussel larvae attached the most effectively particularly to the individuals of the salmon fish populations that lived in the same brooks and rivers. The larvae also grew best on the fish of the home river.

"For example, in the upper course of Luttojoki in Ivalo, we cross-exposed the fish of Hanhioja and Kolmosjoki with the mussels of both rivers, and the result was clear: The mussel larvae of Hanhioja attached the best to the Hanhioja salmon and the mussel larvae of Kolmosjoki to the Kolmosjoki salmon," Taskinen says. A third salmon population that was unfamiliar to both rivers was also used in the experiment, and it was the population to which the larvae attached the least effectively in both rivers.

Researchers’ keepnets for host fish in a mussel river. Credit: Felix Luukkanen
Freshwater pearl mussels on the riverbed. Credit: Jouni Salonen / University of Jyväskylä

Extinction of original migratory fish populations threatens the mussel

The freshwater pearl mussel is endangered and in many places has disappeared from nature regardless of the preservation work that started in the 1950s. Dams built to produce water power have obstructed fish migration, with the result that now many salmon and trout populations are almost lost. The loss to the fish economy caused by hydropower has been compensated with compensatory fish stocking. The research results demonstrated that if a salmon fish population other than the original population of the river is used in a stocking, it may not be that beneficial for the mussel. It does not help the mussel either if stocking takes place in a sea area and the fish do not return to spawn in their home rivers.

The freshwater pearl mussel favors the original salmon fish populations of the home river
A microscopic image of the glochidium larvae of freshwater pearl mussel on the gill of a 
host fish. Credit: Jouni Salonen / University of Jyväskylä

"For the endangered freshwater pearl mussel, it would be important to restore the original fish populations and their natural migration to rivers," says Taskinen. "When possible, the original  population of the river should be favored in compensatory fish stocking, and the stockings should be made in the rivers instead of sea to be beneficial to the freshwater pearl ."

Freshwater mussels can inhibit bacterial diseases

More information: Jouni Taskinen et al, The endangered freshwater pearl mussel Margaritifera margaritifera shows adaptation to a local salmonid host in Finland, Freshwater Biology (2022). DOI: 10.1111/fwb.13882

Australia's first marine Aboriginal archaeological site questioned

Australia's first marine Aboriginal archaeological site questioned
Map of the Dampier Archipelago (Murujuga) showing locations of areas mentioned in the
 text. (Contains modified Copernicus Sentinel data [2020] processed by Sentinel Hub).
 Credit: Geoarchaeology (2022). DOI: 10.1002/gea.21917

A new study from The University of Western Australia has challenged earlier claims that Aboriginal stone artifacts discovered off the Pilbara coast in Western Australia represent Australia's first undisturbed underwater archaeological site.

The original findings were made in a study published in 2020 in PLOS ONE, by a team of archaeologists and scientists from Flinders University, UWA, James Cook University, ARA (Airborne Research Australia) and the University of York.

The team partnered with the Murujuga Aboriginal Corporation to locate and investigate stone scatters at two sites in the Dampier Archipelago.

The "underwater" sites at Cape Bruguieres included hundreds of  found in an area that was dry land many thousands of years ago.

Co-author of the new paper, published in Geoarchaeology, geoarchaeologist Dr. Ingrid Ward from UWA's School of Social Sciences, said it questioned two key claims made in the original paper—that the artifacts were "permanently submerged" and that they were "in situ" and had not been moved since their original deposition.

"In fact, the artifacts occur in a channel ponded well above the lowest tide, so are not permanently submerged," Dr. Ward said.

"Further, past and present oceanographic and sediment transport processes indicate that the lithic  scatters have almost certainly been moved by waves and currents away from where they were first discarded."

The new study was carried out in collaboration with UWA's Dr. Piers Larcombe, Dr. Peter Ross of Flinders University and Dr. Chris Fandry of RPS Energy.

The multidisciplinary team examined the assumptions and claims made in the original paper, concluding that the analysis had been insufficient to justify its findings.

"It remains untested how old the artifacts are—they could be 200 years old, 2,000 years old or 20,000 years old—it is completely unknown at this stage," Dr. Ward said.

Despite this, she said we could still learn a lot from reworked sites.

"For all , the scientific narrative depends on defensible interpretation, which means understanding the processes that have formed the sites we find today," she said.

"Science progresses through repeated cycles of research, publication, challenge and correction, and papers that challenge ideas are a normal part of healthy science. Archaeological research of indigenous coastal and marine sites in Australia is still at an early stage."Aboriginal artifacts reveal first ancient underwater cultural sites in Australia

More information: Ingrid Ward et al, Applying geoarchaeological principles to marine archaeology: A reappraisal of the "first marine" and "in situ" lithic scatters in the Dampier Archipelago, NW Australia, Geoarchaeology (2022). DOI: 10.1002/gea.21917

Jonathan Benjamin et al, Aboriginal artefacts on the continental shelf reveal ancient drowned cultural landscapes in northwest Australia, PLOS ONE (2020). DOI: 10.1371/journal.pone.0233912

Journal information: PLoS ONE 

Provided by University of Western Australia 

Chinese scientists help Africa combat land degradation

Chinese scientists help Africa combat land degradation
PAGGW National 30-m spatial resolution LPD Product. Credit: AIR

Chinese scientists released an online tool, the Great Green Wall Big Data Facilitator, to help African countries combat increasingly severe land degradation on June 16, the 28th World Day to Combat Desertification & Drought.

Land degradation is one of the most significant global ecological and environmental challenges. Africa is particularly vulnerable to land degradation and desertification, and it is the most severely affected region. "Up to 65 percent of productive land is degraded, while desertification affects 45 percent of Africa's ," according to a report of FAO in 2021.

In the United Nations 2030 Agenda for Sustainable Development (the UN 2030 Agenda), UN has described 17 Sustainable Development Goals (SDGs), among which SDG 15 proposes a prospect of "By 2030, combat desertification, restore degraded land and soil, including land affected by desertification, drought, and floods, and strive to achieve a land degradation-neutral world."

To address the data gap in the global land degradation monitoring, a group of Chinese scientists led by Prof. Li Xiaosong from the International Research Center of Big Data for Sustainable Development Goals (CBAS) and the Aerospace Information Research Institute (AIR), Chinese Academy of Sciences (CAS), in partnership with Beijing Normal University, Computer Network Information Center of CAS and Institute of Software of CAS, have developed a 30-meter Land Productivity Dynamics (LPD) calculation tool.

As the world's first 30-meter LPD calculation tool, it can realize the calculation of a 30-meter LPD within the specified global spatial range as well as time period, thereby providing important data support for global land degradation monitoring.

The calculation is built on the SDG Big Data Platform supported by CBAS, which was launched in Beijing in September 2021 to facilitate the implementation of the UN 2030 Agenda.

The "Great Green Wall" is an African-led initiative launched in 2007 with the goal to restore the continent's degraded landscapes and transform millions of lives in the Sahel. To support the development of "Great Green Wall," Chinese scientists use this tool to produce a 30-meter spatial resolution LPD product which covers an area of 9.34 million square kilometers in 11 member countries of the Pan Africa Agency of the Great Green Wall (PAGGW).

The spatiotemporal analysis result shows that from 2013 to 2020, for the PAGGW countries, the land with increasing productivity accounted for 16.25%, and the area with decreasing productivity accounted for 7.36% of the total area.

For the Sahel, the main target area of the Great Green Wall, the land with increasing productivity accounted for 8.45%, while the land with decreasing productivity accounting for 9.24% of the total area, which is not a promising prospect for the development of the Great Green Wall.

The LPD product presented on the Great Green Wall Big Data Facilitator can be used to track the progress of LDN of the target areas. In addition, the platform also provides a knowledge bank about prevention and control of land degradation, which is obtained from successful practices of China's efforts to combat  in Northern China.

Ibrahim Thiaw, Deputy Secretary-General of the U.N. and Executive Secretary of United Nations Convention to Combat Desertification (UNCCD) applauded the launch of this , saying that the results have the potential to facilitate the Great Green Wall of Africa in the future.Image: Desert greenery

Wildlife–human conflicts could shift with climate change

Wildlife–human conflicts could shift with climate change
Researchers from the Institute of Industrial Science, The University of Tokyo, find that the 
risk of human—elephant conflict in Thailand is likely to shift with climate change. 
]Credit: Institute of Industrial Science, The University of Tokyo


As natural areas become increasingly fragmented, the potential for humans and wildlife to interact is growing. Now, researchers from Japan have found that climate change is altering the risk of such interactions.

In a recent study published in Science of the Total Environment, researchers from the Institute of Industrial Science, The University of Tokyo, examined how the risk of human–elephant conflict could change over time. When humans encroach on natural landscapes, the chances of interactions with wildlife increase. Conflicts can arise when wildlife damages livestock or crops, or when human activities damage animal habitat. For example,  are particularly attractive areas for elephants on the hunt for food, which can bring them into contact with mature crops, or with farmers.

"In Thailand, half of the country's population live in  and rely on agriculture," says lead author Nuntikorn Kitratporn. "Thailand also has about three to four thousand wild elephants and deforestation and the growth of commercial agriculture have pushed elephants into increasingly fragmented patches of habitat, increasing the chance of interactions between humans and elephants."

Climate change is bringing additional complexity to these interactions, as changing  lead to changes in the behavior and distribution of elephants. In rural areas where people depend on agriculture to survive, human–elephant conflict may well intensify in the future. To assess the risk of this, the researchers used a risk framework that incorporated different possible scenarios. They used this framework to examine the recent spatial distribution of human–elephant conflict (2000–2019) in Thailand and how it may look in the near future (2024–2044). Different projections of future climate and socioeconomic conditions were incorporated into the framework and the effects on  were examined.

"We found a spatial shift in risk toward northern areas and higher latitudes," says Kitratporn. "In other areas, habitat is likely to become less suitable over time, which could first increase and gradually decrease the risk of interactions."

Understanding how –wildlife interactions may change in the future is vital for long-term planning. The results from this study could be used to develop planning strategies in affected communities and raise awareness of ways in which humans and wildlife can coexist.High risk of conflict between humans and elephants and lions

More information: Nuntikorn Kitratporn et al, Human-elephant conflict risk assessment under coupled climatic and anthropogenic changes in Thailand, Science of The Total Environment (2022). DOI: 10.1016/j.scitotenv.2022.155174

Journal information: Science of the Total Environment 

Provided by University of Tokyo 

 

Winter honey bees show resistance to a common insecticide

Winter Honey Bees Show Resistance to a Common Insecticide
Honey bees feed on imidacloprid during a cage experiment. Credit: Mohamed Alburaki, 
ARS

Winter honey bees, compared to newly emerged summer bees, have a better ability to withstand the harmful effects of a widely-used insecticide in pest management, according to a recent study published in Apidologie.

United States Department of Agriculture (USDA), Agricultural Research Service (ARS) researchers from the Bee Research Laboratory in Beltsville, Maryland, found  honey bees' consumption of a nearly lethal, imidacloprid-laced syrup did not affect their survival during the study.

Imidacloprid is an  made to mimic nicotine and is toxic to insects. This powerful insecticide is widely used in agriculture for pest management control. Honey bees are likely to encounter imidacloprid while foraging in the field or through contaminated hive products.

"Although imidacloprid toxicity to honey bees is an important concern for beekeepers, our results provide good news," said Miguel Corona and Mohamed Alburaki, researchers at the ARS Bee Research Laboratory. "Our research shows that winter honey bees have unrecognized physiological mechanisms to counteract the effects of insecticides."

The study assessed differences in diet behaviors for summer and winter honey bees in a controlled laboratory setting. Researchers provided sublethal doses of the imidacloprid-laced syrup to bees as necessary. Winter bees showed a preference to consuming imidacloprid-laced syrup over untreated sugar syrup while summer honey bees made the safe choice and avoided consuming the laced syrup each time.

According to Corona, it is important to study the differences of summer and winter  bees' diets. Honey bee colonies survive extreme seasonal differences in temperature and forage by producing two seasonal phenotypes of workers: summer and winter bees. These seasonal phenotypes differ significantly in their psychological characteristics as well as their susceptibility to disease and ability to handle poisonous substances.

"Winter bees and  bees undergo physiological changes to cope with drastic seasonal changes in temperature and the availability of nutritional resources," said Corona and Alburaki. "Our results suggest that long-lived winter bees are especially well-adapted to tolerate higher levels of chemical stressors."

Corona said that although the study's results show that winter  could tolerate more intoxication by imidacloprid, they are still susceptible to higher concentrations of this insecticide in field settings.Native Asian honeybees have higher toxin tolerance than introduced bees

More information: Mohamed Alburaki et al, Influence of honey bee seasonal phenotype and emerging conditions on diet behavior and susceptibility to imidacloprid, Apidologie (2022). DOI: 10.1007/s13592-022-00922-9

Heat wave of 2021 created 'perfect storm' for shellfish die-off

New study: 2021 heat wave created ‘perfect storm’ for shellfish die-off
Dead oysters seen along a shoreline in Washington state, following a record heat 
wave in summer 2021. Credit: Blair Paul

It's hard to forget the excruciating heat that blanketed the Pacific Northwest in late June 2021. Temperatures in Oregon, Washington and British Columbia soared to well above 100 degrees Fahrenheit, with Seattle setting an all-time heat record of 108 degrees on June 28.

During the , also called a heat dome, scientists and community members alike noticed a disturbing uptick of dying and dead  on some beaches in Washington and British Columbia, both in the Salish Sea and along the outer coast. The observers quickly realized they were living through an unprecedented event and they organized to document the shellfish die-offs as they happened in real time.

Now, a team led by the University of Washington has compiled and analyzed hundreds of these field observations to produce the first comprehensive report of the impacts of the 2021 heat wave on shellfish. The researchers found that many shellfish were victims of a "perfect storm" of factors that contributed to widespread death: The lowest low tides of the year occurred during the year's hottest days—and at the warmest times of day. The results were published online June 20 in the journal Ecology.

"You really couldn't have come up with a worse scenario for intertidal organisms," said lead author Wendel Raymond, a research scientist at UW Friday Harbor Laboratories. "This analysis has given us a really good general picture of how shellfish were impacted by the heat wave, but we know this isn't even the full story."

The research team leveraged existing collaborations across tribes, state and federal agencies, academia and nonprofits. They devised a simple survey and five-point rating system (1 = much worse than normal to 5 = much better than normal) and asked participants to provide ratings based on their knowledge of a species in that location. In total, they gathered 203 observations from 108 unique locations, from central British Columbia down to Willapa Bay, Washington.

Heat wave of 2021 created ‘perfect storm’ for shellfish die-off
Joe Williams, front, and Darrell Williams with the Swinomish Indian Tribal Community’s
 Fisheries Department dig clams on a beach in Skagit Bay as part of a survey that is
 conducted to estimate clam biomass. Credit: Northwest Indian Fisheries Commission

"The strength of this study and what it really highlights is the value of local knowledge and also the importance of understanding natural history," said co-author P. Sean McDonald, a UW associate teaching professor in environmental studies and aquatic and fishery sciences. "This is the first step and a snapshot, if you will, of what shellfish experienced on the beaches during the heat wave."

The researchers found that each species' ecology contributed to its general success or failure to survive the extreme heat. For example, some shellfish that naturally burrow deep beneath the surface, like butter clams, usually fared better than ones that typically ride out low tide just below the sand's surface, such as cockles.

They also found that location mattered. Shellfish on the outer coast experienced low tide about four hours earlier than shellfish on inland beaches. For inland shellfish, low tide—or when the most shellfish were exposed—hit around solar noon, when the sun was directly overhead.

Additionally, air temperatures were much higher at inland sites compared to the outer coast, causing more stress on inland populations. For example, California mussels, found almost exclusively on the outer coast, mostly survived the heat while bay mussels, found in more inner coastal sites, were more likely to die from heat exposure. More water movement and wave action on the outer coast also likely helped lessen the impacts of the heat on shellfish along those beaches.

Many shellfish don't tend to move much on any given beach, so where they naturally live in the intertidal zone also contributed to their success or failure, the researchers found. For example, acorn barnacles that live higher on the shore generally were more impacted than clams and oysters that are lower on the beach and more likely to remain under water.

Heat wave of 2021 created ‘perfect storm’ for shellfish die-off
Julie Barber, senior shellfish biologist with the Swinomish Indian Tribal Community, 
quantifying recent butter clam deaths on a beach in Skagit Bay, Washington, in July 2021,
 following a record heat wave. Credit: Northwest Indian Fisheries Commission

"Although this event had negative effects on marine life, there is hope that can be found in this work. Not all locations and species were affected equally, offering clues to pathways to resiliency in the future," said co-author Annie Raymond, a shellfish biologist with Jamestown S'Klallam Tribe.

Perhaps most surprisingly, the researchers noticed interesting patterns in survival rates among shellfish on the same beach. In some locations, shellfish in the path of freshwater runoff on one section of beach survived, while others just a few miles away perished. If a tree hung over part of a beach and shaded the sand, those shellfish generally made it while others didn't. Co-author Julie Barber, senior shellfish biologist with the Swinomish Indian Tribal Community, remembers seeing those patterns while walking the beaches of Skagit Bay, and in some locations, being surrounded by dead cockles in every direction.

"It was pretty unsettling, and I've never seen anything like it," Barber said. She remembers exchanging emails with colleagues from around the region as they noticed similar mass die-offs on their local beaches, then realizing that they urgently needed to coordinate and document what was happening.

"This effort was a beautiful demonstration of how collaborators can come together with one common cause—which in our case was trying to understand what happened to these shellfish," Barber said.

Because the heat wave occurred during the time frame when many shellfish are reproducing, the mass die-offs could impact those populations for at least several years, highlighting the need for long-term monitoring, the researchers said. And as climate change continues to produce more frequent extreme heat events, shellfish deaths like those of last summer may become more of a common reality.

Heat wave of 2021 created ‘perfect storm’ for shellfish die-off
Dead cockles seen on a beach after record heat in July 2021 in Skagit Bay, Washington.
 Credit: James McArdle

"The Swinomish Indian Tribal Community is proud to be a leader in this important scientific research that assessed in real time the devastating impacts to our shellfish resources from the unprecedented heat dome last summer. Shellfish are a priority first food that our tribal community relies on for spiritual and subsistence nourishment. Last summer's extreme weather event reinforced to us that we must act faster to ensure climate resiliency for our community's long-term health and well-being," said Swinomish Tribal Chairman Steve Edwards.

"Once the effects of the heat wave started to become apparent, the collaboration that emerged was amazing as managers and scientists worked quickly to put together a rapid response to capture information," said co-author Camille Speck, Puget Sound intertidal bivalve manager for Washington Department of Fish and Wildlife. "We still have so much to learn about the effects of the heat wave on Salish Sea marine ecosystems, and more work to do as managers to prepare for the next one and develop informed responses. These conversations are happening now, and it is our hope that we will be better prepared for whatever comes next."

Other co-authors are Megan Dethier of the UW; Teri King of UW-based Washington Sea Grant; Christopher Harley of University of British Columbia; Blair Paul of Skokomish Indian Tribe; and Elizabeth Tobin of Jamestown S'Klallam Tribe. More than two dozen individuals contributed data to this project.Yessotoxins produced by phytoplankton caused summer mass shellfish mortality events in Washington

More information: Wendel W. Raymond et al, Assessment of the impacts of an unprecedented heatwave on intertidal shellfish of the Salish Sea, Ecology (2022). DOI: 10.1002/ecy.3798

Journal information: Ecology 

Provided by University of Washington 

 A blueprint for life forms on Mars?

A blueprint for life forms on Mars?
Microbes taken from surface sediment near Lost Hammer Spring, Canada, about 900 km 
south of the North Pole, could provide a blueprint for the kind of life forms that may once
 have existed, or may still exist, on Mars. Credit: Elisse Magnuson.

The extremely salty, very cold, and almost oxygen-free environment under the permafrost of Lost Hammer Spring in Canada's High Arctic is the one that most closely resembles certain areas on Mars. So, if you want to learn more about the kinds of life forms that could once have existed—or may still exist—on Mars, this is a good place to look. After much searching under extremely difficult conditions, McGill University researchers have found microbes that have never been identified before. Moreover, by using state-of-the-art genomic techniques, they have gained insight into their metabolisms

In a recent paper in The ISME Journal, the scientists demonstrate, for the first time, that microbial communities found living in Canada's High Arctic, in conditions analogous to those on Mars, can survive by eating and breathing simple inorganic compounds of a kind that have been detected on Mars (such as methane, sulfide, sulfate, carbon monoxide, and carbon dioxide). This discovery is so compelling that samples of the Lost Hammer  sediments were selected by the European Space Agency to test the life detection capabilities of the instruments they plan to use on the next ExoMars Mission.

Developing a blueprint for life on Mars

Lost Hammer Spring, in Nunavut in Canada's High Arctic, is one of the coldest and saltiest terrestrial springs discovered to date. The water which travels up through 600 meters of permafrost to the surface is extremely salty (~24% salinity), perennially at sub-zero temperatures (~−5 °C) and contains almost no oxygen (<1ppm dissolved oxygen). The very high salt concentrations keep the Lost Hammer spring from freezing, thus maintaining a liquid  habitat even at sub-zero temperatures. These conditions are analogous to those found in certain areas on Mars, where widespread salt deposits and possible cold salt springs have been observed. And while earlier studies have found evidence of microbes in this kind of Mars-like environment—this is one of a very few studies to find microbes alive and active

To gain insight into the kind of life forms that could exist on Mars, a McGill University research team, led by Lyle Whyte of the Department of Natural Resource Sciences, has used state-of-the-art genomic tools and single cell microbiology methods to identify and characterize a novel, and more importantly, an active microbial community in this unique spring. Finding the microbes and then sequencing their DNA and mRNA was no easy task.

It takes an unusual life form to survive in difficult conditions

"It took a couple of years of working with the sediment before we were able to successfully detect active microbial communities," explains Elisse Magnuson, a Ph.D. student in Whyte's lab, and the first author on the paper. "The saltiness of the environment interferes with both the extraction and the sequencing of the microbes, so when we were able to find evidence of active , it was a very satisfying experience."

The team isolated and sequenced DNA from the spring community, allowing them to reconstruct genomes from approximately 110 microorganisms, most of which have never been seen before. These genomes have allowed the team to determine how such creatures survive and thrive in this unique extreme environment, acted as blueprints for potential life forms in similar environments. Through mRNA sequencing, the team were able to identify active genes in the genomes and essentially identify some very unusual microbes actively metabolizing in the extreme  environment.

No need for organic material to support life

"The microbes we found and described at Lost Hammer Spring are surprising, because, unlike other microorganisms, they don't depend on organic material or oxygen to live," adds Whyte. "Instead, they survive by eating and breathing simple inorganic compounds such as methane, sulfides, sulfate,  and carbon dioxide, all of which are found on Mars. They can also fix  and nitrogen gasses from the atmosphere, all of which makes them highly adapted to both surviving and thriving in very extreme environments on Earth and beyond."

The next steps in the research will be to culture and further characterize the most abundant and active members of this strange microbial ecosystem, to better understand why and how they are thriving in the very cold, salty, muck of the Lost Hammer Spring. The researchers hope that this, in turn, will help in the interpretation of the exciting but enigmatic sulfur and carbon isotopes that were very recently obtained from the NASA Curiosity Rover in the Gale Crater on MarsAstrophysicists investigate the possibility of life below the surface of Mars

More information: Elisse Magnuson et al, Active lithoautotrophic and methane-oxidizing microbial community in an anoxic, sub-zero, and hypersaline High Arctic spring, The ISME Journal (2022). DOI: 10.1038/s41396-022-01233-8

Journal information: ISME Journal 

Provided by McGill University 

Tuesday, June 21, 2022

Here’s why pumpkin toadlets are such clumsy jumpers

Tiny inner ear canals may make it hard for the frogs to orient themselves in space


Tiny Brachycephalus frogs from southern Brazil can leap into the air but have trouble landing.

LUIZ F. RIBEIRO



By Meghan Rosen
JUNE 15, 2022 


Some frogs just can’t stick the landing.

After launching into a leap, pumpkin toadlets careen through the air as if flung from a toddler’s fist. They roll, cartwheel or backflip and then plummet to the ground, often belly flopping or crash-landing on their backs.

“I’ve looked at a lot of frogs and these are the weirdest things I’ve ever seen,” says Richard Essner, Jr., a vertebrate zoologist at Southern Illinois University Edwardsville.

Essner and colleagues now propose an explanation for why the tiny frogs are such clumsy jumpers. The animals lack the proper gyroscopic equipment to sense small changes in rotation, the team suggests June 15 in Science Advances.
Brachycephalus pernix frogs have trouble sensing small changes in rotation, which makes landing jumps difficult, a new study suggests. The frogs can roll, cartwheel or backflip through the air, and then hit the ground on their backs or bellies.

When Essner saw videos of Brachycephalus frogs’ awkward aerial maneuvers, he was so shocked that he hopped on a plane to study the animals with his colleagues in Brazil. Small enough to fit on a person’s thumbnail, the frogs are tricky to find in the wild. Scientists listen for the amphibians’ high-pitched, buzzy calls and then scoop leaf litter into a bag, hoping to find a few toadlets.



In the lab, the team used high-speed video to record more than 100 tiny frog jumps. The klutzy tumbles suggested that the toadlets have trouble orienting themselves in space.

Typically, fluid sloshing through bony tubes in the inner ear help vertebrates sense their body’s position. CT scans revealed that the frogs’ tubes are the smallest ever recorded for adult vertebrates. Studies of other tiny animals suggest that the tubes don’t work so well in miniature. It’s difficult for the fluid to flow freely, Essner says. That means the frogs probably can’t sense how they’re twirling through the air, making it tough to prep for landing.

It’s possible that bony back plates offer some species crash protection, but the animals may stay grounded for safety (SN: 4/3/19). As Essner observed, the frogs are “almost always crawling really slowly.”

sciencenews.org

CITATIONS

R. Essner, Jr., et al.
Semicircular canal size constrains vestibular function in miniaturized frogs. Science Advances. Published online June 15, 2022. doi: 10.1126/sciadv.abn1104.



Butterflies may lose their ‘tails’ like lizards

The spindly parts seem to be a magnet for birds and may break off easily, facilitating escape


The sail swallowtail (Iphiclides podalirius) has tail-like projections on its 
hind wings that may divert attacking birds away from the butterfly’s vital parts.
CAROLINE GAUVIN/MOMENT/GETTY IMAGES PLUS


By Jake Buehler
JUNE 15, 2022 AT 7:00 AM


On some butterfly wings, “tails” may be more than just elegant adornments. They’re survival tools too, a study suggests.

The tails seem to attract the attention of attacking birds, keeping them away from a butterfly’s more vital body parts, researchers report May 25 in the Proceedings of the Royal Society B. The finding could help explain why wing tails have independently evolved multiple times across different moth and butterfly groups.

Evolutionary biologist Ariane Chotard of the National Museum of Natural History in Paris studies the wings of swallowtail butterflies, which make up the hundreds of species in the family Papilionidae. “A lot of these butterflies display tails,” Chotard says. “And we don’t really know why.”

Some butterfly species with false head or eyespot patterns on their wings are known to receive more attacks from predators in those regions. And Chotard and her colleagues wondered if tails were also a target.

So in the summer of 2020, the researchers collected 138 sail swallowtail butterflies (Iphiclides podalirius) from the wild in Ariege, France. Sail swallowtails — found throughout Eurasia — sport two, conspicuous black tails on hind wings with some blue and orange spotting, contrasting greatly with the rest of the insects’ yellow, striped coloration.

Among the collected swallowtails, 65, or 41 percent, had damaged wings, all of which had at least one tail damaged. When all 130 wings in this group of damaged butterflies were counted, more than 82 percent of the wings had damaged tails, suggesting that predators may be targeting the spindly parts



To test that idea, the team kept wild-caught songbirds called great tits (Parus major) in cages. The researchers then showed the birds dummy butterflies made from gluing real swallowtail wings to a fake body made of small pieces of black cardboard, and filmed the birds’ attacks on the faux insects.

Forty-three out of 59 beak strikes, or nearly 73 percent, were on the hind wings. Twenty-three, or 39 percent, of the strikes touched both a tail and colored areas on the upper part of a hind wing simultaneously, more than any other body area on the dummies.
A captive great tit (Parus major) attacks the hind wings and “tails” of a dummy made with real wings from a sail swallowtail butterfly (Iphiclides podalirius). A new study suggests that the tails deflect attacks away from key body parts to brittle extensions that easily tear off, allowing the insect to flee.

Chotard and her colleagues also measured how much force was needed to tear various sections of the swallowtail wing. They found that the vein of the hind wing tail was the most fragile part of the wing and is probably the location most apt to break off in a hungry bird’s beak.

Taken together, the findings suggest that swallowtail tails deflect attacks away from the butterfly’s vulnerable body to brittle extensions that easily tear off, allowing the insect to escape, the researchers say. This may be similar to the strategy some lizards use when sacrificing their detachable tails to hungry predators.

It’s unclear if there are any costs to losing one or two tails, Chotard says. “You survived, you escaped from a predator, but maybe there’s a trade-off and maybe your flight will be [slower].”

Some moth tails can deflect the attacks of echolocating bats (SN: 2/16/15). “Now we have evidence that butterfly tails provide a similar benefit against visual predators,” says evolutionary biologist Juliette Rubin of the University of Florida in Gainesville who was not involved with the study.

Future work determining the survival benefits of the tails could be one next step, Rubin says. “It would be informative to see how live swallowtail butterflies — both with and without tails — fare against bird predators.”

sciencenews.org

CITATIONS

A. Chotard et al. Evidence of attack deflection suggests adaptive evolution of wing tails in butterflies. Proceedings of the Royal Society B. Vol. 289, May 25, 2022. doi: 10.1098/rspb.2022.0562.

About Jake Buehler