https://phys.org/news/2025-04-whale-urine-important-life-sea.html

"Previous work suggested that whale feces was important to ecosystems. These giant mammals bring nutrients from the depths where they feed to shallow waters.

"This effect is called the "whale pump" and it can enhance the photosynthetic rate of plankton, which is the basis of the food web. Nutrients are not distributed evenly across the ocean and in some areas, phytoplankton populations are limited because there aren't enough of specific elements, such as iron.

"Some whale species perform long migrations across the ocean. Humpback whales (Megaptera novaeangliae) perform the longest migration of any mammal at around 10,000 km, moving nutrients across ocean basins as they travel. To some extent, the whale pump influences carbon cycling and storage too.

"Whales can also help cycle nutrients in the ocean when they disturb the seabed as they feed. Gray whales (Eschrichtius robustus), for example, are known to forage for invertebrates on the seafloor and stir up sediments which release nutrients, such as nitrogen, phosphorus and iron.

"Another key area of research describes the oasis ecosystems that whale carcasses provide to deep sea species, from hagfish (Eptatretus deani) and sleeper sharks (Somniosis pacificus) to crustacea, mollusks, nematodes and bacteria. The great whales have large bodies with high amounts of lipids in their bones. These lipids are food for lots of organisms and whale carcasses create mini ecosystems in the deep.

***

"A recent study published in Nature Communications indicates that baleen whales' urine could also have a crucial function in oceans. Some whale species can produce up to 950 liters of urine per day, and this means they can relocate nutrients to tropical grounds low in nutrients. Many baleen whales, such as humpback and gray whales, feed in polar and subpolar regions during summer, then migrate to equatorial breeding areas en masse into relatively small areas during the winter.

"During migration, the whales carry detritus like placenta, urine, feces and if they die, carcasses. For example, the paper describes how gray whales tend to winter in several feeding grounds across the north Pacific Ocean and aggregate in summer in a few small bays on the coast of California.

"The researchers describe how gray, humpback and right whales (Eubalaena glacialis) transport carbon and nitrogen to the tropics, in what they call the "great whale conveyor belt." Globally, for these species, this process results in more than 46,000 tons of biomass (whales' total mass and the nutrients they contain) and almost 4,000 tons of nitrogen per year, transferred to poor nutrient grounds.

"Most of this nitrogen transport comes from whale urine, which stimulates phytoplankton growth and photosynthesis. This increase in the rate of photosynthesis could lead to 18,180 tons of carbon being drawn down from the atmosphere. Other large baleen whales probably also contribute to this effect but there is less data on their distributions and ecology.

***

"The contribution that these animals will make to solving our climate crisis through stimulating photosynthesis is under debate and their ability to balance the global carbon budget in the face of human-related emissions may be negligible. However, the more we learn about these ocean giants, the more we understand the ways in which whales are vital to marine ecosystems."

Comment: whale contributions from poop to pee to dead carcasses vitally support ocean life. All species make their contributions in many ways.

https://phys.org/news/2025-04-loss-nature-unsung-heroes-threatens.html

"The joint study, led by a team from the University of Western Australia, Australia's national science agency CSIRO and James Cook University, found the loss of dominant ant species was quickly compensated by rarer species, with other similar native ant species effectively picking up the slack by taking on the additional roles left behind by the original species.

"'Insects are everywhere and some people question what all these species do in ecosystems," study lead author and JCU entomologist Dr. Peter Yeeles said.

"'Here, the research is showing that they provide a built-in redundancy that allows ecosystems to absorb shocks.

"'Think of them like pieces of scaffolding. Remove one, or a few, and the structure still stands because each part offers a degree of redundancy to the other parts. Redundancy makes systems resilient. Without it, even small disturbances can cause big collapses."

"But Dr. Yeeles said the study also found that there is likely to be a limit to how much the ant community can compensate for species losses.

"'Losing the common species can be like replacing a few reliable generalists with a team of s"You might maintain performance, but you also increase the risk if one of them goes missing.

"'With so much reliance on specific roles, losing any more species could cause much greater ecosystem damage than before."

"Dr. Yeeles said the study highlighted how important dominant ant species were in performing everyday tasks that keep ecosystems "running smoothly.'"

"'It is easy to forget how important ants are in the majority of terrestrial ecosystems. They're often referred to as ecosystem engineers because they have such profound effects on the ecosystems they live in," he said."

***

"'We must act now to protect not only rare species, but also the everyday insects that quietly keep our world running.'"

Comment: ecosystems maintain life. Every organism has its place.

https://www.sciencedaily.com/releases/2024/10/241018162550.htm

"Mississippi State University is part of a European-American collaboration studying how human activities, like fertilizer use and polluting, are impacting nitrogen-fixing plants which are crucial for maintaining healthy ecosystems by adding nitrogen to the soil.

"MSU Assistant Professor Ryan A. Folk of the Department of Biological Sciences co-authored a study published today [Oct. 18] in Science Advances, showing that increased nitrogen deposition from human activity is reducing the diversity and evolutionary distinctiveness of nitrogen-fixing plants.

"Lead author Pablo Moreno García, at the University of Arizona, said excessive nitrogen from agriculture and industry makes nitrogen fixers less competitive, leading to simplified plant communities with fewer species of nitrogen fixers.

"Folk said, "While others predicted climate change might benefit nitrogen fixers, our research shows this has not happened. Humans are changing Earth in multiple ways that affect nitrogen fixers, and nitrogen deposition is overwhelming as a harmful effect. Nitrogen, the first number listed on a bag of fertilizer, is often the most important plant macronutrient in natural and agricultural systems, so the loss of these plants threatens both biodiversity and ecosystem stability."

Abstract: https://www.science.org/doi/10.1126/sciadv.adp7953

"Biological nitrogen fixation is a fundamental part of ecosystem functioning. Anthropogenic nitrogen deposition and climate change may, however, limit the competitive advantage of nitrogen-fixing plants, leading to reduced relative diversity of nitrogen-fixing plants. Yet, assessments of changes of nitrogen-fixing plant long-term community diversity are rare. Here, we examine temporal trends in the diversity of nitrogen-fixing plants and their relationships with anthropogenic nitrogen deposition while accounting for changes in temperature and aridity. We used forest-floor vegetation resurveys of temperate forests in Europe and the United States spanning multiple decades. Nitrogen-fixer richness declined as nitrogen deposition increased over time but did not respond to changes in climate. Phylogenetic diversity also declined, as distinct lineages of N-fixers were lost between surveys, but the “winners” and “losers” among nitrogen-fixing lineages varied among study sites, suggesting that losses are context dependent. Anthropogenic nitrogen deposition reduces nitrogen-fixing plant diversity in ways that may strongly affect natural nitrogen fixation. (my bold)

***

"Nitrogen deposition is associated with long-term declines in the proportion of N-fixing plants across temperate forests of Europe and the US. Unexpectedly, changes in temperature and aridity did not contribute to the observed temporal changes in N-fixing diversity, likely reflecting the greater relative importance of N deposition for N-fixing plants. Given the effect of N deposition on N-fixer richness, we should be cautious about predicting future changes in N-fixers based solely on climatic changes without understanding the complex interplays with anthropogenically driven changes in soil nutrient conditions. Declines in N-fixer PD mostly reflect the loss of evolutionarily divergent species, leading to fewer distinct N-fixing lineages. However, no consistent clades of winner or loser species are found, indicating that the response of N-fixing plants to N deposition is driven by local environmental conditions (and possibly priority effects). Therefore, the strategic benefits of temperature and aridity increases for N-fixing species may be curtailed by N deposition, reducing N-fixing richness and their associated ecosystem services.

Comment: Any ecosystem that loses phylogenetic diversity is weakened. The Earth is covered by ecosystems that influence each other in important ways. Every oddity I present here is an important part of the overall system. Nothing is unimportant, which dhw should note when he derides something.

https://www.science.org/doi/10.1126/science.adp6198?utm_source=sfmc&utm_medium=emai...

"Across many ecosystems, declining biodiversity leads to lower biomass and loss of other ecosystem functions. Much of the research in this area has focused on plant communities, with less attention paid to consumers, who play the important role of accumulating and synthesizing organic nutrients. Shipley et al. investigated how the diversity of insects and spiders affects community-level concentrations of polyunsaturated fatty acids (PUFAs), one type of essential nutrient. They found higher biomass and higher PUFA mass in more diverse communities in both terrestrial and aquatic systems and in different land uses. In human-dominated systems, both predator biomass and PUFA biomass were lower at a given level of species richness than in natural systems, suggesting a negative shift in function." —Bianca Lopez (my bold)

***

"Abstract
Human land-use intensification threatens arthropod (for example, insect and spider) biodiversity across aquatic and terrestrial ecosystems. Insects and spiders play critical roles in ecosystems by accumulating and synthesizing organic nutrients such as polyunsaturated fatty acids (PUFAs). However, links between biodiversity and nutrient content of insect and spider communities have yet to be quantified. We relate insect and spider richness to biomass and PUFA-mass from stream and terrestrial communities encompassing nine land uses. PUFA-mass and biomass relate positively to biodiversity across ecosystems. In terrestrial systems, human-dominated areas have lower biomass and PUFA-mass than more natural areas, even at equivalent levels of richness. Aquatic ecosystems have consistently higher PUFA-mass than terrestrial ecosystems. Our findings reinforce the importance of conserving biodiversity and highlight the distinctive benefits of aquatic biodiversity." (my bold)

"Conclusions
Our study shows that insect and spider diversity is of fundamental importance in both terrestrial and aquatic ecosystems and influences the availability of biomass as well as nutritionally relevant fatty acids. Our results confirm those of previous studies of biodiversity-biomass relationships for consumers and primary producers (8) while demonstrating that biodiversity also increases the availability of critical organic nutrients across ecosystems that encompass a wide range of human land uses and habitat types. We observed strong effects of diversity on nutrient availability across land-use categories, which highlights the importance of conserving biodiversity for ecosystem functioning even in human-dominated landscapes. Concerningly, urbanized terrestrial environments with low insect and spider diversity had biomass of substantially lower n-3 LC-PUFA density than more natural environments. There was a clear biomass deficit of insects and spiders in human-dominated terrestrial communities, particularly at low diversity. Additionally, the proportion of predator biomass (i.e., the more LC-PUFA–rich part of the community) to total terrestrial biomass increased at a slower rate with species richness in human-dominated areas. This suggests that predatory taxa such as beetles and spiders may be especially susceptible to anthropogenic stressors (11), which may explain why their own predators, such as birds, mammals, and reptiles, are also struggling most in human-dominated habitats."

Comment: the simplest of organisms contribute to necessary dietary nutrients. This in-depth study shows that ecosystems are important all the way to the lowest forms. Everything is here for a reason.

https://www.sciencealert.com/wolves-vanished-across-america-and-were-still-uncovering-t...

"The haunting howls of wolves fell mostly silent across America's West by the 1930s.

"Their loss to the region has been largely overlooked by humans, even in our scientific research, a new review finds, but the impact of their absence is written loudly in the missing trees.

"'Researchers generally agree that the loss of wolves and other large predators, followed by increased browsing by elk (Cervus canadensis), was the main cause for the decline in woody plant communities in many Western parks," write Oregon State University ecologist William Ripple and colleagues in their new paper.

"This is another example of how everything on our living planet is tightly interconnected and how we fail to consider these vital links.

***

"'Various national parks in the western United States, which are considered the crown jewels of American wilderness, lack their apex predators, resulting in them being shadows of their supposed ecological integrity."

"Loss of an ecosystem's apex predator causes domino effects through an ecosystem's food chain known as trophic cascades. As ecosystems can be such complex messes of interactions it's not always easy to see how trophic cascades will play out, particularly given they can be context-dependent.

"So not every trophic cascade is found in each landscape, even if the same species are present. Reintroducing lost species, like the return of wolves to Yellowstone National Park, can't necessarily repair all the broken connections either, once the cascade of changes have taken place.

"But historical records across the 11 parks reveal declines in several tree species, including black (Populus trichocarpa) and plains (Populus deltoides) cottonwoods, since wolves were eradicated.

"Not only has removal of wolves messed with the web of connections stemming from their predation on deer, it's impacted the ecosystem interactions around coyotes (Canis latrans) as well.

"'Wolves can reduce coyote populations, thereby mediating their predation of prey and smaller-predator populations, such as rodents, ungulates, small carnivores, leporids, and birds," write Ripple and team.

***

"The same scenario is occurring in the oceans, where the absence of reef sharks means too many green turtles are gorging on vital CO2 sequestering seagrass meadows, and in Australia, where the widespread eradication of dingoes means smaller predators like foxes and cats are having their fill of predator-naive marsupials.

"Kangaroos are now also overabundant thanks to the lack of dingoes, joining deer in the top ten most abundant wild animals by biomass. Ripple previously found there are almost six times more deer in areas without wolves compared to areas with them.

"Ecosystem restoration is more critical than ever as our destructive impacts on our living biosphere accelerate. But to have any success, it is crucial that we better understand the interactions that govern these environments in their historical functioning state, the researchers urge."

Comment: I've introduced this problem before, but a repeat now and then is keeps us reminded that ecosystems are vital. It is a world-wide problem from mistaken human activity.

https://www.discovermagazine.com/planet-earth/large-and-in-charge-hippos-are-stirring-u...

"An ocean away from their kindred in Africa, a group of invasive hippos roaming the Colombian wild has garnered quite the controversial reputation. The river-dwelling mammals don’t exactly belong in this environment, yet an estimated 91 of them currently inhabit the Magdalena River basin in Colombia.

"As the hippo’s numbers burgeon, the scramble to curtail population growth has reached a boiling point. The consequences that have arisen from the hippos’ presence, scientists warn, will only amplify if the animals aren’t dealt with swiftly.

***

"A 2023 paper published in Scientific Reports estimates that there are 91 hippos currently in the Magdalena River basin and that the population is growing at a rate of 9.6 percent per year. At this rate, there will be 230 hippos by 2032 and over 1,000 by 2050.

"The hippos have impacted the local ecosystem by moving more organic terrestrial matter to aquatic environments. The increased nutrients that they bring by grazing on grass and then excreting in water fertilizes the lakes and rivers, which may lead to eutrophication — caused by an excess of nutrients and associated with harmful algal blooms.

"People who live in nearby agricultural villages, and especially those who access the Magdalena River, could be exposed to danger from the hippos. According to the paper, two people have been attacked and injured by the hippos since 2019. The threats that humans and wildlife face will likely escalate in the future, depending on how the population is managed.

"The first hippos in Colombia — 3 females and 1 male — came at the behest of drug lord Pablo Escobar, who imported them in 1981 from a U.S. zoo. They became a feature of Escobar’s own private zoo at his sprawling estate, Hacienda Nápoles.

"The zoo shut down in 1993 after Escobar’s death, but the hippos remained on site due to challenges transporting them. In the coming years, they reproduced and made the surrounding landscape their home. From 1993 to 2009, 4 hippos turned into 28.

"The initial solution to stop the hippos’ growth was culling, or killing for population control. But when authorities culled a male hippo in 2009, a fierce reaction from animal rights activists followed. Ever since a judicial ruling banned the shooting of hippos, authorities have struggled to commit to alternative methods.

***

"It will take deliberate consideration by authorities to choose the path forward, but the paper’s authors say that delaying for too long could create a bigger impact as the hippo population grows.

"If the population control process doesn’t start soon, the hippos will likely expand into other territories. The ecological impacts and the potential for conflict with humans could enter new levels of severity in the future as a result. Regardless of what option is chosen, it seems that this critical moment has already spawned serious repercussions as the invasive hippos continue to proliferate."

Comment: just like the problems in Australia. Wrong animals in wrong places creates nothing but ecological trouble. The small population start suggests this herd has a poor gene pool which could produce abnormal sickly hippos.

https://www.sciencealert.com/something-strange-happens-to-wolves-infected-by-infamous-m...

"A study of 26 years' worth of wolf behavioral data, and an analysis of the blood of 229 wolves, has shown that infection with the parasite Toxoplasma gondii makes wolves 46 times more likely to become a pack leader.

***

"If you have a cat, you've probably heard of this parasite before. The microscopic organism can only sexually reproduce in the bodies of felines, but it can infect and thrive in pretty much all warm-blooded animals.

"This includes humans, where it can cause a typically symptomless (but still potentially fatal) parasitic disease called toxoplasmosis.

***

"Animals such as rats infected with the parasite start taking more risks, and in some cases actually become fatally attracted to the scent of feline urine, and thus more likely to be killed by them.

"For larger animals, such as chimpanzees, it means an increased risk of a run-in with a larger cat, such as a leopard. Hyenas infected with T. gondii also are more likely to be killed by lions.

"Gray wolves (Canis lupus) in the Yellowstone National Park aren't exactly cat prey. But sometimes their territory overlaps with that of cougars (Puma concolor), known carriers of T. gondii, and the two species both prey on the elk (Cervus canadensis), bison (Bison bison), and mule deer (Odocoileus hemionus) that also can be found there.

"It's possible that wolves also become infected, perhaps from occasionally eating dead cougars, or ingesting cougar poo.

***

"They found that wolves with a lot of territory overlap with cougars were more likely to be infected with T. gondii.

"But there was a behavioral consequence, too, with significantly increased risk-taking.

"Infected wolves were 11 times more likely to disperse from their pack, into new territory. Infected males had a 50 percent probability of leaving their pack within six months, compared with a more typical 21 months for the uninfected.

"Similarly, infected females had 25 percent chance of leaving their pack within 30 months, compared with 48 months for those who weren't infected.

"Infected wolves were also way more likely to become pack leaders. T. gondii may increase testosterone levels, which could in turn lead to heightened aggression and dominance, which are traits that would help a wolf assert itself as a pack leader.

"This has a couple of important consequences. Pack leaders are the ones who reproduce, and T. gondii transmission can be congenital, passed from mother to offspring. But it can also affect the dynamics of the entire pack.

"'Due to the group-living structure of the gray wolf pack, the pack leaders have a disproportionate influence on their pack mates and on group decisions," the researchers write in their paper.

"'If the lead wolves are infected with T. gondii and show behavioral changes … this may create a dynamic whereby behavior, triggered by the parasite in one wolf, influences the rest of the wolves in the pack."

"If, for example, the pack leader seeks out the scent of cougar pee as they boldly push into new territory, they could face greater exposure to the parasite, thus a greater rate of T. gondii infection throughout the wolf population. This generates a sort of feedback loop of increased overlap and infection.

"It's compelling evidence that tiny, understudied agents can have a huge influence on ecosystem dynamics.

"'This study demonstrates how community-level interactions can affect individual behavior and could potentially scale up to group-level decision-making, population biology, and community ecology," the researchers write.

"'Incorporating the implications of parasite infections into future wildlife research is vital to understanding the impacts of parasites on individuals, groups, populations, and ecosystem processes."

Comment: Every little change in an ecosystem has big consequences. T. gondii is part of the huge diversity of life.

https://www.sciencenews.org/article/invasive-ant-lion-dinner-trees-ecosystem

"When big-headed ants (Pheidole megacephala) invade the savanna, they kill off native acacia ants (genus Crematogaster), robbing local whistling thorn trees of their valiant defenders against hungry elephants. Without ants to bite them, the elephants rip up the thorn trees, opening up the grassland, which makes it harder for lions to catch their preferred zebra meals. Lions end up hunting buffalo instead. The findings, published online January 25 in Science, show that invasive species’ effects can be very indirect — and suggest that changes in different low-level mutualisms might also echo up food webs in other ecosystems.

"Over the past 15 years or so, wildlife ecologist Jake Goheen and his colleagues at the University of Wyoming in Laramie and the Ol Pejeta Conservancy in Laikipia, Kenya, have been studying how acacia ants protect whistling thorn trees (SN: 6/15/10). When an elephant tries to eat the tree, “ants swarm up inside its nostrils and bite from the inside out,” Goheen says.

"he scientists were also examining what the lions in the conservancy eat as part of a separate study. “One of the things that we found … was that lions are much more effective, they’re more successful with their hunts in areas where tree cover is high,” Goheen says.

"But what happens when tree cover is suddenly low? To find out, Goheen and his colleagues collared six lionesses from the local prides to track their activity and kills. The team also set up experimental plots where big-headed ants had invaded, and where the native ants still held sway.

"The big-headed ant arrived in the conservancy between 2002 and 2005, Goheen says. “We think it probably was imported on produce,” brought into the houses or tourist camps in the area. The invading insects kill local acacia ants wherever they find them. And other studies have shown that without defending ants, pachyderms tore down the thorn trees five to seven times more often.

***

"Areas with big-headed ants, the team showed, had 2.67 times higher visibility than areas without — meaning that lions could see farther, but so could their prey.

Lions relied on the cover of trees to pounce on hapless zebras nearby: Where visibility was low, the probability of a zebra kill was 62 percent. But when visibility was high, the lion’s chance of taking down a zebra dropped to only 22 percent.

"Over the three years of the study, zebra dinners decreased from 67 percent to 42 percent of lion kills. But the lions didn’t go hungry. Instead, they went for beef. Buffalo kills increased from zero to 42 percent of kills over the study period. It’s a risky diet, Goheen says. Buffalo “are big and feisty,” and lions hunting buffalo are more likely to be injured.

"The study shows that “the disruption of a mutualism can have cascading effects on other species in the community,” says Emilio Bruna, a plant ecologist at the University of Florida in Gainesville. “Those effects can be unexpected and indirect.”

"It’s a clue, Bruna says, that ecologists should be looking out for other pairs like the acacia ant and the thorn tree, where a single special relationship is a foundation for an ecosystem and a single anthill could cause a savanna-wide shift in who is eating who."

Comment: a very important contribution. It is not just a top predator but a little item like an ant on a special tree.

https://www.sciencealert.com/worlds-rarest-insect-makes-stunning-comeback-after-near-ex...

"Only 20 to 30 'tree lobsters' remain in the wild. This single fragile population was rediscovered in 2001 after the insects were presumed extinct for 80 years.

"These wild Lord Howe Island stick insects (Dryococelus australis) currently cling to their precarious existence on a near-vertical volcanic outcrop called Ball's Pyramid.

"Now, San Diego Zoo is inviting visitors to see the extraordinary, extinction-defying Australian animals in person.

"Prone to catastrophic weather events and landslides, Ball's Pyramid is not exactly a safe place for a critically endangered species.

"Here there's only one species of food plant, Melaleuca howeana, for the herbivorous stick insects to graze. These shrubs are being strangled by an invasive vine, which can't be entirely removed as they're holding soil onto the cliffs with their roots.

"So several zoos around the world have been working to bring these large, flightless phasmids down from their metaphorical and quite literal cliff edge.

***

"Lord Howe Island stick insects once clustered on branches of Moreton Bay figs (Ficus macrophylla) and wooly tea trees (Leptospermum lanigerum) of their namesake island home, off the east coast of Australia.

"But the chunky, hand-sized stick insect proved the perfect meal for the rat invasion of 1918. The shipwrecked rats feasted and multiplied and feasted some more, until not a single 'tree lobster' could be found.

"The rats also devoured further native species until they no longer existed on the island, including five birds, two plants, and 12 other invertebrates.

"After no sightings since 1920, the Lord Howe stick insect was declared extinct in 1986. But rumors of insect poop and skin sheds from climbers in the 1960s betrayed the insects' secret refuge on a volcanic sea stack 23 kilometers away from the island.

***

"This incredible feat of survival, despite critically low numbers in such a desolate place, is likely due to the female's ability to clone themselves through parthenogenetic reproduction.

"Researchers were hesitant to put the remaining population at further risk by removing individuals, but in 2003, a rescue team safely extracted four of the black stick insects to begin a breeding program.

"Together, Melbourne, Bristol (now closed), and San Diego Zoos have established a captive population, now numbering in the thousands.

"Since 2019, there has been a massive effort to eliminate the rats on Lord Howe Island with the help of rat-detecting dogs. From endangered land snails to the flightless Lord Howe Woodhen, an incredible resurgence of the island's unique wildlife has followed.

"What is unfolding is an ecological renaissance," Lord Howe Island resident Hank Bower told Laura Chung at The Sydney Morning Herald in 2022.

"'There's a vine which we didn't know what the fruit looked like, people are taking photos of insects and sending them to the Australian Museum who are saying we've only got three of those on record ever but we are seeing hundreds of them. Everything is blooming, all the plants are flowering and we are seeing a carpet of seedlings."

"The zoos hope their now-thriving populations will be used to reestablish the insects back on their island home once it's deemed safely rat-free.

"'This species was once a major converter of vegetative matter and played an important function in the island's ecology as an ecosystem engineer, increasing the richness and speeding up the recycling of nutrients," says NSW state government ecologist Nicholas Carlile.

"'They are currently a missing piece of the puzzle and it would be phenomenal to see them back in the forest someday.'"

Comment: ecosystems support all of life on Earth. Everything living is here for a purpose. Those who do not understand that viewpoint have a confused view as to why species exist.

https://www.sciencealert.com/thriving-otters-in-north-america-linked-to-nuclear-weapons...

"Three atomic weapons went off at Amchitka in the late 1960s and early 1970s, including the largest underground detonation the US has ever set off.

"No humans lived on the island, but the biggest blast, in 1971, killed at least 900 sea otters. The Atomic Energy Commission, the government agency in charge of nuclear research, had predicted at most 240 otters would die.

"If ecologists and others hadn't pushed to relocate some otters before the detonation, it probably would have been much worse.

"'There was pressure from the state of Alaska as well as environmental groups," conservation biologist and author, Joe Roman told Business Insider. "They ended up moving hundreds of otters."

"By the time the AEC was looking at Amchitka in the 1960s, the island's sea otter population was one of only a handful that had survived the sea mammals' near extinction a century earlier.

"Their luscious pelts were prized as "soft gold." In the 1700s and 1800s, hunters killed about one million sea otters to sell their fur.

"The drop in population was alarming, from between 150,000 to 300,000 in the early 1700s to around 2,000 just 200 years later. Russia, Japan, Britain, and the US signed a fur treaty to help protect the animals in 1911. Over the next several decades, sea otter numbers rose to around 30,000.

***

"A US Fish and Wildlife Service biologist, Karl Kenyon, had already worked on relocating some otters to areas they'd lived before the 18th century hunting. The detonations at Amchitka were a good reason to move even more, ecologists and biologists thought.

"If the AEC would pay for it, Vania said, the scientists could relocate the otters.

***

"Over the next 50 years, the sea otter populations in many of these locations, like Sitka, Alaska, would go from several dozen to hundreds or thousands. "All the sea otters — of which there are thousands — in Sitka now are the descendants of these airlifted sea otters," Roman said.

***

"'In the absence of sea otters, you have a lot of sea urchins," Roman said. "When you have a lot of urchins, they create what's called urchin barrens."

"The sea urchins eat the kelp holdfasts, which anchor the algae. Roman compares it to sawing down a forest. The kelp eventually disappear.

"One of the otters' favorite foods is sea urchin. And they can eat a lot of them. "They have very high metabolisms," Roman said. "They're eating machines." When the sea urchin numbers drop, the kelp return.

"In Sitka Sound, the sea otters reduced the sea urchin population by 99%. Kelp forests exploded in return.

"The forests provide food and shelter for more than 800 species, including sea lions, harbor seals, lingcod, gobies, moray eels, octopuses, crabs, sea anemones, and brittle stars," Roman wrote.

"The kelp forests are also amazing at capturing carbon, a concern for the warming planet.

"The otters can also affect land animals, Roman wrote, either directly, as food for wolves on Alaska's Pleasant Island, or indirectly, with the kelp forests that attracted birds that prey on fish.

***

"...the US didn't consult indigenous and First Nations people before unleashing the otters. The mammals brought back the kelp forests, but they destroyed a reliable source of food for many people.

"'Sea otters don't just eat urchins," Roman said. "They also eat geoducks and other valuable benthic invertebrates in the area." That includes crabs and clams. "And of course that brings them into conflict with fishers in that area," he said.

"Suddenly, otters appeared where they hadn't been for generations. "So no one remembers having sea otters in that area," Roman said. "They're used to harvesting these invertebrates, and they're quite abundant in the absence of a predator."

"Their voracious appetite is one reason some people call otters the "rats of the sea." For some Alaskans and Canadians, they're seen as a nuisance."

Comment: another example of ecosystem complexity showing how the whole bush of life interrelates and come from a 99.9% evolutionary loss of forms.

https://ecoevocommunity.nature.com/posts/meta-analysis-identifies-native-priority-as-a-...

" Biological invasion is considered to be one of the main drivers of biodiversity loss with potential negative socio-economic impacts. Invasive alien plant species are well adapted to rapid establishment and exploitation of the resources of disturbed environments, therefore disturbed and intensively managed habitats may support high levels of invasive species. Ecological restoration – defined by the Society for Ecological Restoration as the process of assisting the recovery of an ecosystem that has been degraded, damaged or destroyed – is increasingly recognized as a relevant tool to combat land degradation and biodiversity loss, and also invasive alien species. As the invasion problem becomes increasingly serious, there is an urgent need to develop more innovative, effective and proactive strategies to help improve the resistance of restored communities to invasion, limiting the establishment and further spread of invasive alien species.

**

"The long-term results show that seeding with native species has been the best method as opposed to mowing and N immobilization, although our system - open sandy grasslands - still has relatively large remnants in the landscape that act as a source of native propagules. In addition to increasing the richness and cover of target species, seed-based restoration has also been most successful in reducing the cover of invasive alien species, although it has not completely eliminated invasive species.

***

"Based on our quantitative review of 48 papers published in relation to seed-based ecological restoration experiments, we demonstrate the potential of seed-based ecological restoration in controlling the establishment and growth of invasive alien species up to 40 %, that can be increased to 50 % by involving the priority effect. Already providing one week of advantage for native species can visibly suppress invasive alien species, although cannot eliminate them. Seeding functionally similar species generally had a neutral effect on invasive alien species, as also shown by previous reviews in the topic, probably partly due to the fact that resources are often not limiting in restoration and in experimental settings. High-density seeding is effective in controlling invasive alien species, but there can be thresholds above which further increases in seeding density may not result in increased invasion resistance.

"The study also highlights the need to integrate research across geographical regions, global invasive species and potential resistance mechanisms to improve the predictive capacity of invasion ecology and to identify best restoration practices to prevent and control invasive alien species."

Comment: it is increasingly important to create these studies so we can adequately manage all ecosystems properly, providing the huge human population its food supply.

https://www.sciencemagazinedigital.org/sciencemagazine/library/item/03_november_2023/41...

"Restoring vegetation in degraded ecosystems is an increasingly common practice for promoting biodiversity and ecological function, but successful implementation is hampered by an incomplete understanding of the processes that limit restoration success. By synthesizing terrestrial and aquatic studies globally (2594 experimental tests from 610 articles), we reveal substantial herbivore control of vegetation under restoration. Herbivores at restoration sites reduced vegetation abundance more strongly (by 89%, on average) than those at relatively undegraded sites and suppressed, rather than fostered, plant diversity. These effects were particularly pronounced in regions with higher temperatures and lower precipitation. Excluding targeted herbivores temporarily or introducing their predators improved restoration by magnitudes similar to or greater than those achieved by managing plant competition or facilitation. Thus, managing herbivory is a promising strategy for enhancing vegetation restoration efforts.

***

"Our findings offer insights toward achieving myriad restoration commitments. Massive revegetation efforts are being implemented globally, including the Bonn Challenge, Africa’s Great Green Wall, and the Blue Carbon Initiative. By demonstrating global, substantial impacts of herbivores on the abundance and diversity of vegetation under restoration, our study suggests that revegetation efforts, if implemented merely by removing the cause of degradation, recreating abiotic conditions, or planting propagules, are unlikely to achieve maximal outcomes. Rather, substantial improvements can be achieved by comanaging herbivory (by either plant- or consumer-based approaches). By revealing climates and other moderators of variations in herbivore effects at restoration sites, our study can help restoration practitioners pinpoint where and when managing herbivory may be particularly crucial, including in the tropics, where global priority areas for vegetation restoration are concentrated, and in hot, dry regions as well as in the years ahead with respect to future climates. Indeed, as climate change and human activities, which are often beyond the immediate control of local managers, continue to disrupt food webs and affect vegetation through top-down processes, managing herbivory may become increasingly relevant and tractable for enhancing recovery and resilience.

Comment: all of Earth is covered by ecosystems based on vegetation, eaten by herbivores who are eaten by carnivores. All in a neat balance. And all provides human food, which is not in balanced supply at this time. That is why these studies aerev so important.

Another review emphasizes main points:

https://mail.google.com/mail/u/0/#inbox/FMfcgzGwHVPSSpjSNmWLvBGwQPrpDrJJ

"Restoration projects around the world aim to rectify the damage people have done to the planet’s ecosystems. But while they often prevent further habitat losses, they’re not so great at actually bringing back wild spaces. According to a new survey of almost 2600 restoration projects published in this week’s issue of Science, there’s one thing that these projects mostly neglect that could more than double plant regrowth: bringing back ecosystem predators.

"The team’s meta-analysis revealed that hungry herbivores are one of the main barriers to restoration success—yet only 10% of the projects examined included any means of limiting their damage. And that, the authors found, is where predators shine. While excluding plant-eaters roughly doubled the amount plant life that grew at a site, introducing predators increased vegetation abundance by a whopping 372% for projects involving planting native species. (my bold)

“'If we want more plants, we have to let more predators in or restore their populations,” study coauthor Brian Silliman says in a press release. “It’s like learning a new gardening trick that doubles your yield.'”

https://www.sciencenews.org/article/melting-glacier-peru-llamas-climate

"When glaciers melt, they leave behind barren landscapes that can take decades to support plants and animals. But a new study found that within just three years, such exposed land was revitalized by llamas, whose activity nourished the soil and fostered plant growth.

"By the foot of Peru’s shrinking Uruashraju glacier, researchers partnered with local farmers to capture and herd llamas on four designated plots. For three days a month from 2019 to 2022, the llamas (Llama glama) grazed the plots, fertilizing them with dung and dispersing viable seeds from droppings and fur.

"By the end of that time, the otherwise arid and easily eroded soil stabilized, grew richer in nutrients and supported 57 percent more plant cover than before, geographer Anaїs Zimmer and colleagues report September 24 in Scientific Reports.

"Such a revival of the ancestral Andean practice of camelid herding could potentially cushion the crops, animals and livelihoods of local communities from the impacts of climate change, says Zimmer, of the University of Texas at Austin.

"As is the case worldwide, glaciers are disappearing in Peru’s Cordillera Blanca mountains at an unprecedented rate. And as the ice shrinks, nearby ecosystems wither: They lose access to summertime supplies of freshwater and sometimes encounter harmful acidic minerals in rocks once covered by the glaciers.

" Llamas may help counter some of these effects. Their transformation of the land, as seen in the new study, could reduce rock weathering and help the soil hold onto more moisture, thus limiting the acidic runoff that can poison farmers’ crops. Such contamination is one reason local farmers partnered with the researchers. The animals’ behavior could one day even generate new pasturelands as soil quality improves.

***

"...the size and speed of the changes the llamas helped bring about surprised the researchers. From 2021 to 2022, the average amount of plant cover in the llama plots grew from about 9 percent to nearly 14 percent — faster than it did in four control plots. Four new types of plant species also moved into the experimental plots over the course of the study.

"The research underscores the valuable roles animals play in shaping landscapes, says ecologist Kelsey Reider of James Madison University in Harrisonburg, Va., who was not involved with the new research. Sprinkling nutrients such as phosphorus over the soil can produce similar effects on plant growth, she says, but “the animals themselves are doing a lot.”

"For one, animal poo is special: It holds onto both moisture and microbes. For another, in grazing and trampling on plants, the llamas weed out dominant plants, making space for new species."

Comment: it is not always a top predator that is needed. This shows the effect any living organisms have on transforming the Earth.

https://evolutionnews.org/2023/10/hidden-service-animals-earthworms-are-only-the-beginn...

"Without earthworms, scientists at Colorado State calculate, we would have 25 percent less food productivity from plants. How much food service do they provide for us? About 140 million metric tons is the estimate.

"Earthworms help establish healthy soils by supporting plant growth in multiple ways — building good soil structure, assisting in water capture and aiding in the beneficial churn of organic matter that makes nutrients more available to plants. Other research has also shown that earthworms can facilitate the production of plant-growth-promoting hormones and help plants protect themselves against common soil pathogens.

"These services are delivered by soft, squishy annelid worms that are easily crushed. The soil is their dark utopia. Moving about with radial and longitudinal muscles, they “worm” their way through each crevice, plowing the soil in a way that helps plant roots navigate to nutrients the worms have made available.

***

[A picture of muscles] "They are impressions of radial worm muscles just 1 millimeter in diameter. The structure allows the muscles to “introvert” like a plunger as the worm stretches and squeezes. They are works of art.

"These particular muscles are not from earthworms (annelids) but from cycloneuralians, “a group of animals that includes roundworms, horsehair worms, mud dragons, and many other creatures.” This kind of structure is required for worms to navigate through the tight spaces in their environments. And they were detected in fossils from the early Cambrian!

"In this study, the researchers described three phosphatized and millimeter-sized specimens from the early Fortunian Kuanchuanpu Formation (ca. 535 Ma) of China. Among them, one specimen (NIGP179459) is better preserved, and consists of five successively larger rings that are interconnected with 19 radial and 36 longitudinal structures. The rings were compressed to certain degrees, implying that they were pliable when alive.

"Muscles imply nerves and coordination by a central nervous system. A diagram further down in the article shows the arrangement of seven kinds of radial and longitudinal muscles. The musculature in annelids (which also abruptly appeared in the Cambrian Explosion) is no less wondrous. (my bold)

***

“This work supports the evolution of scalidophoran-like or priapulan-like introvert musculature in cycloneuralians at the beginning of the Cambrian Period.” (my bold)

***

"Soil organisms mediate unique functions we rely on for food, fiber, and human and planetary health. Despite the significance of soil life, we lack a quantitative estimate of soil biodiversity, making it challenging to advocate for the importance of protecting, preserving, and restoring soil life. Here, we show that soil is likely home to 59% of life including everything from microbes to mammals, making it the singular most biodiverse habitat on Earth. Our enumeration can enable stakeholders to more quantitatively advocate for soils in the face of the biodiversity crisis. (my bold)

"This is twice previous estimates for soil biodiversity. Some 98.6 percent of annelids live underground; other species include fungi, plants, and isoptera (termites). The services they provide to the biosphere are incompletely understood. In a companion piece in PNAS, Richard Bardgett remarks about the new estimate:

***

"...the estimate that 59% of all species inhabit soil, with several taxonomic groups being almost entirely soil-based, points to soil being the most speciose, but poorly explored, habitat on Earth. This staggering level of species richness in soil, combined with growing awareness of the functional importance of soil biodiversity for supporting ecosystem services, their resilience to environmental change, and of its sensitivity to multiple global change factors, provides a strong basis to advocate for explicit inclusion of soil biodiversity in international strategies for biodiversity conservation and the protection of threatened soil species.

"...it’s a sobering thought to realize that much of our livelihood depends on hidden service animals under our feet.

***

"Free-living organisms and microbes that live their lives on and in the ocean’s top meter of seawater are thought to play vital roles in ocean ecosystems, nutrient cycles, oxygen production, the carbon pump, and other earth processes. Yet, surprisingly, relatively little is known about these vital marine communities — collectively known as neuston — their evolution, how they develop, how they affect their environment, and how their environment affects them."

Comment: dhw take note. God planned for our food supply back in the Cambrian. God knows what He is doing. dhw has no idea, except to criticize God's choice of action.

https://ecoevocommunity.nature.com/posts/mycorrhizal-fungi-influence-global-forest-dive...

"I was introduced to the Janzen-Connell hypothesis and negative conspecific density dependence (CDD) around 2015, when I was working on my Master’s degree. It was fascinating that pathogens, by definition harmful organisms, could actually generate and sustain community level plant diversity. Specialized (or relatively specialized) pathogens could create a zone of repulsion under adult trees, reducing the recruitment of their offspring, and leaving space for other species. This negative ‘conspecific density dependence’ (CDD), prevents any one species from dominating and allows a diversity of species to establish. I was working with a professor and her PhD student to see whether this applied within species – are species more successful when grown under genetically more dissimilar individuals of the same species? Because I was excited by all things mycorrhizal fungi, I was hired as a work study student to score all the seedling roots for arbuscular mycorrhizal fungi (the mycorrhizal relationship 70-80% of plant species worldwide depend on).

***

"In this study, we used census data across 43 large-scale forest inventory plots worldwide, including nearly 3 million stems and over 4,000 species. Ultimately, we found that EM tree species show weaker negative CDD, likely due to greater host specificity or pathogen protection compared to tree species associating with arbuscular mycorrhizal fungi. This, coupled with the well-known global latitudinal gradient in mycorrhizal types – with ectomycorrhizal plants increasing with absolute latitude – suggests forest mycorrhizal strategy is an essential component of the overall weakening of CDD and lower tree diversity observed at higher latitudes. We also showed that both mycorrhizal types exhibit positive conmycorrhizal feedbacks, with trees benefitting from the presence of heterospecific neighbors that form the same mycorrhizal type, potentially by tapping into shared neighboring mycorrhizal fungi. This positive mycorrhizal feedback at the community level may explain why many forest stands exhibit mycorrhizal bimodality globally, with stands where both mycorrhizal strategies coexist occurring far less than expected by chance. Collectively, these findings suggest that mycorrhizal interactions may play a foundational role in global forest diversity patterns and structure. These findings bring to light the important role of the forest fungal microbiome, mutualisms, and positive feedback in maintaining global patterns of forest biodiversity." (my bold)

Comment: More evidence of how delicately it all fits together. And the underlying issue is maintaining a tenuous food supply for humans.

https://www.sciencealert.com/cicadas-mysterious-and-dramatic-life-cycle-can-re-wire-ent...

"While the natural phenomenon of the periodical cicada is well known, the impact of this and similar 'biomass pulses' on local ecosystems has never been adequately mapped.

***

"Stuffed to the brim with cicadas, many birds lost their appetite for oak-feeding caterpillars. Plasticine models of the grubs used to gauge predation rates revealed a marked drop in consumption in 2021, with bird strikes declining from around 30 percent to just 10 percent for several months.

"One of the site's most common caterpillar, the grub of the raspberry bud dagger moth (Acronicta increta), showed a marked change in size following the Brood X emergence, with as much as a 50-fold increase in the proportion of large larvae. Presumably, with so many cicadas on offer, the choicest of caterpillars found themselves with a temporary reprieve.

"Moving further down the food chain, a relative rise in oak-feeding herbivores is bound to be bad news for the oak trees. Sure enough, the summer of 2021 saw a spike in damage to the leaves of the immature oaks.

"Just what this might mean in the long term isn't clear. Though prior research on acorn-producing oaks strongly suggests that an increase in herbivores could constrain that season's production of new trees.

***

"'Our study demonstrates that periodical cicada emergences can 'rewire' forest food webs, altering interaction strengths and pathways of energy flow that affect multiple trophic levels," the researchers write in their published report. (my bold)

"Even beyond predation, the deaths of vast numbers of periodical cicadas provide the soil with a pulse of nutrients.

"Meanwhile, as the next brood of cicadas nestle in for a long rest, their burrows loosen and aerate the soil, almost as an apology to the trees above for the brief disruption they'll bring to the ecosystem when they too eventually emerge."

Comment: all tightly organized ecosystems have effects like this. All ecosystems show this knock-on effects even from small changes. It is my conjecture that all ecosystems are interrelated so tightly that changes in one will affect others. And all of this affects the borderline human food supply. Note this opinion:

https://www.sciencemagazinedigital.org/sciencemagazine/library/item/20_october_2023/414...

"Although periodical cicada emergences are short-lived phenomena, lasting for only 5 to 6 weeks, they can initiate a cascade of ecological impacts that propagate up and down the food chain. By providing abundant living prey to predators, carcasses to scavengers and decomposers, and an infusion of nutrients into both terrestrial and aquatic ecosystems, these brief yet intense events initiate a wide range of responses that can last from days to years and can occur immediately or with a considerable time lag. For instance, analyses of long-term data collected by the North American Breeding Bird Survey revealed that populations of some species were abundant only during emergence years and subsequently declined (for example, black- and yellowbilled cuckoos), whereas others were scarce during emergence years but increased substantially the following year, and then stabilized (for example, tufted titmice and gray catbirds). Migratory birds exhibiting cicada-mediated numerical responses can potentially extend the cicadas’ legacy across continents when they travel to distant overwintering sites, affecting recipient communities through “cross-boundary subsidy cascades." (my bold)

https://www.sciencedaily.com/releases/2023/10/231009191700.htm

"A team of researchers from Queen Mary University of London and the University of Campinas in Brazil has found that tropical forest ecosystems are more reliant on aquatic insects than temperate forest ecosystems and are therefore more vulnerable to disruptions to the links between land and water.

***

"They found that the spiders were consuming more aquatic insect prey in the tropics than in the UK, resulting in higher overall dietary diversity in the tropical food-webs, on-land. Their results indicated that tropical terrestrial animals are more reliant on and impacted by emerging aquatic insects. This suggests tropical environments are more vulnerable to future disruption to the interconnections between land and water.

"'Our findings show that we cannot simply apply knowledge from research in temperate zones to protect tropical ecosystems," said Dr. Pavel Kratina, senior author of the study and Senior Lecturer in Ecology at Queen Mary University of London. "That tropical ecosystems are more vulnerable to disruptions to the links between land and water is worrying considering the increasing human pressures on tropical freshwater ecosystems, which are among the most threatened in the world."

"Emerging aquatic insects can become a pathway for negative human impacts to move from one environment to another. For example, polluting a stream may reduce insect numbers, which may in-turn reduce availability of nutritious food for land-based predators. Tropical aquatic insects are under threat of catastrophic declines because of human activity and climate change -- the researchers' results suggest this would have cascading consequences across tropical environments.

***

"The researchers' study stresses the need for greater protection of riparian buffers and broader consideration of the links between ecosystems, rather than considering different habitats in isolation, particularly in the tropics."

Comment: in ecosystems the relationships are important down to the tiny midge. Whatever is eating insects becomes meals for the next predators on the ladder until it reaches the jungle cat. Some of it becomes human food, the supply of which is globally threatened. My next banana is threatened by a loss of aquatic insects. In creating a huge bush of life, God intentionally supplied humans their food supply.

https://phys.org/news/2023-09-animal-evolution-predatory-lifestyle.html

"...the researchers were able to show that the young life stages (larvae) of the small sea anemone Aiptasia actively feed on living prey and are not dependent on algae. To capture its prey, the anemone larvae use specialized stinging cells and a simple neuronal network.

"In the early embryonic development of multicellular organisms, gastrulation plays a key role. "In its simplest form, the gastrula develops from a hollow sphere of cells, the blastula, forming a larval stage with gut and mouth; imagine pushing a ball inwards at one side. All animals pass through this gastrula stage, which could also have existed at the beginning of animal evolution," explains Prof. Holstein, a development and evolutionary biologist

"Ira Mägele, a member of his research group, succeeded in proving that already in the late gastrula stage, the larvae of the Aiptasia sea anemone capture prey of suitable size with their stinging cells, ingest them with their mouth and digest them in their primitive gut.

"The Aiptasia sea anemone is a model system for research on endosymbiosis in corals and other cnidarians. "Corals live in nutrient-poor waters and as larvae or young polyps, take up symbiotic algae cells. In Aiptasia, however, this process is important for adults but does not lead to growth and settlement of the larvae, suggesting that nutrition is a critical step in closing the life cycle," states Holstein.

"Laboratory studies of the nutritional conditions showed that the food for the tiny Aiptasia larvae had to be small enough and alive. Nauplius larvae of Tisbe copepods, 50 to 80 micrometers small, are of similar size to Aiptasia larvae, making them an ideal food.

"The larvae increase continually and rapidly in size, followed by settlement on the substrate and metamorphosis into primary polyps. "In this way, we were able to grow mature polyps as well as their descendants for the first time," explains Mägele.

***

"As Prof. Holstein underscores, the data obtained paint a new picture of the predatory lifestyle as a primary characteristic of the cnidarian gastrula. Evolutionary theorist Ernst Haeckel (1834 to 1919) first posed the "gastrula hypothesis."

"'But Haeckel's hypothetical gastrula was a particle-filtering life form, like sponges. In contrast, the predatory gastrula of Aiptasia and other cnidarians possess specialized stinging cells used for capturing prey," says Holstein.

"The predatory lifestyle of gastrula-like forms with extrusive organelles that excrete toxins and are likewise found in single-celled organisms and simple worms, could have been a critical driver of the early evolution of multicellular organisms and the development of complex, organized nervous systems, according to Holstein."

Comment: dhw's worry that God invented a dog-eat-dog predatory lifestyle is shown here, and the Garden of Eden is gone. Trilobites ate what was available:

https://www.msn.com/en-us/news/technology/fossil-of-a-trilobite-discovered-with-its-las...

See the photo.

https://www.sciencealert.com/it-took-just-one-wolf-to-revive-an-entire-forest-ecosystem...

"In 1997, a lone wolf crossed an ice bridge that briefly connected Canada with the remote Isle Royale, which lies off the coast of Michigan in Lake Superior and is renowned for its rich biodiversity.

"His arrival revived the flagging fortunes of the wider wolf population, which had been hit by disease and inbreeding, and triggered cascading effects that improved the health of the overall forest ecosystem, a study in Science Advances showed Wednesday.

"'Issues like inbreeding and low genetic diversity are an important concern for scientists," first author Sarah Hoy, an ecologist at Michigan Technological University told AFP.

"'But this is the first study that shows when you have these genetic issues, they don't just impact the particular population and increase the risk that they will go extinct: they also have these really big knock on effects on all the other species."

"The first wolves arrived on the island in the late 1940s, and their main prey are moose – giving rise to the longest running study of a predator-prey system anywhere in the world.

"But by the 1980s, the wolves were in trouble due to the arrival of canine parvovirus which drove their numbers down from a high of 50 to around 12.

"Though the disease eventually disappeared, the population didn't recover right away. The reason was severe inbreeding, which caused lower reproductive success, as well as poorer health outcomes such as spinal deformities of the kind often seen in purebred dogs.

***

"Enter the immigrant, identified as "M93" by scientists, but affectionately nicknamed "The Old Gray Guy."

"M93 was unrelated to the existing population, and also had the advantage of being unusually large – a big benefit when defending turf from rivals or taking down 800 pound ungulates.

"He quickly became the breeding male in one of the island's three wolf packs and went on to sire 34 pups, greatly improving the genetic health of the population and the kill rate of its prey.

"Moose are voracious herbivores, consuming up to 30 pounds (14 kilograms) of vegetation a day. By reducing their numbers, the wolves helped bring the forest back into balance, which was most notable in the effects on balsam firs – the species commonly used as Christmas trees.

"With fewer moose, the trees began growing at rates not seen in decades, which is vital for the renewal of the forest and the myriad plant and animal species that depend on it.

"The benefits brought by M93's arrival lasted around a decade, then the situation deteriorated once more – ironically as a result of his extreme reproductive success.

"By 2008, two years after his death, 60 percent of the wolf population's gene pool was inherited from M93, which led to a return of genetic deterioration.

"M93 himself began breeding with his daughter after his mate died, and simultaneous inbreeding by other members triggered a rapid population decline until 2015, when there were just two wolves left: a father-daughter pair who were also half siblings.

"Fortunately, a restoration program beginning in 2018 has once more brought balance to the system, and there are currently around 30 wolves and just under a thousand moose on the island.

"For Hoy, a key takeaway is that the same principle of inserting just a small number of individuals could be applied to other imperiled predator populations that suffer from the harmful effects of inbreeding, such as lions or cheetahs, to similarly improve their ecosystems.

"William Ripple, a professor of ecology at Oregon State University who was not part of the research, told AFP it was an "important study" that advances understanding "by showing that genetic processes may limit the ecological effects of a keystone species, the gray wolf.'"

Comment: this shows the delicate balance in ecosystems. All life on Earth is in an ecosystem, each 0f which must maintain its balance with an apex predator.

https://www.sciencealert.com/a-hidden-food-web-exists-in-the-desert-and-it-thrives-on-d...

"Living in an arid region is a precarious business. Harsh conditions make growing tough for plants, meaning every shoot and leaf is all the more precious, even when they're dead and decaying.

"A new study conducted at Boolcoomatta Station Reserve in outback South Australia has demonstrated the importance of vegetative leftovers in fueling a desert ecosystem – and revealing an unintuitive alliance between termites and dingoes.

***

"Drier periods are a lot less exciting and consequently have attracted less attention."

"But these dry times are important, as they dominate life's existence in arid environments.

***

"Brown food webs are those where the primary food source is decaying vegetation rather than living plants. This rotting plant tissue is recycled back into food energy for the rest of the web when consumed by detritivores, like termites and worms, which are nutriment for small vertebrates.

"Brown webs exist in most habitats, but their impact may be more obvious in areas with fewer resources, like drylands and deserts.

"The researchers found the plots of land which were exposed to kangaroo overpopulation and feral goats showed reduced amounts of both decaying plant material and living vegetation. This caused a cascade of responses throughout the entire web.

"'We found that less dead biomass due to overgrazing herbivores can lead to a reduction in termites," explains Wijas.

""Fewer termites, the principal decomposers in these environments, could ultimately result in a reduction in the number of lizards and small mammals in arid ecosystems, as many of these small vertebrates feed on termites."

***

"In the desert, however, as there's already such a small amount of plant growth that herbivores gobbling up too much of the vegetation means there are not enough leftovers to become the dead plant stuff that feeds detritivores.

"This cascades into fewer small scurrying lizards and mammals like dunnarts – teeny marsupials native to Australia – that feed on the detritivores, and less food for the larger animals such as eagles and snakes that eat the scurriers in turn.

"It's long been established that kangaroos are over-abundant across arid Australia. This problem has arisen, at least in part, because there's a critical component of both the green and brown food webs missing from the equation: an apex predator.

"Humans eradicated dingoes from much of the arid landscape to protect grazing sheep, even going so far as to construct a massive, 5,600-kilometer-long (3,490 mile) dingo fence across south-eastern Australia.

"'Kangaroos occur in large numbers across much of arid Australia because populations of their principal predator, the dingo, have been suppressed. The creation of artificial water points to supply water to livestock, and inadvertently to kangaroos, have also helped kangaroos to survive through dry periods," explains Letnic.

***

"Removing dingoes from the landscape has driven native Australian grasslands to give way to problematically overabundant woody shrublands. These provide cover from which feral cats and foxes can pounce out and devour native endangered marsupials unchecked. The excess grazing has changed the shapes of sand dunes, and the difference in vegetation patterns can even be seen from space.

"Yet, unbeknownst to much of the public, culling of one of the most crucial parts of the arid continent's natural food webs continues under the guise of a 'wild dog problem'.

"While more work is needed to confirm the results, as plot sizes in the study were small and the team did not directly link the abundance of termites to vertebrate numbers, the new findings add to mounting research revealing just how reliant different species within ecosystems are on each other, even those seemingly unconnected, like dingoes and termites.

"'Our findings are one of the first to show in arid ecosystems that where herbivores were excluded, there was greater biomass of dead grass. In turn, there were more termites and predators of termites inside the exclosures," concludes Wijas."

Comment: always the same, poor human judgement in removing top predators. Ecosystems reform automatically to every change, rarely for the best. Humans are top predators of their Earth-wide ecosystem. These systems studies help us learn to use our position wisely.