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Posts Tagged ‘ecosystem’

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Photo: Rebecca Kordas/UBC
Limpets are easy to overlook — so too is their effect on the environment. But careful consideration of how all the life forms in an area interact is key to understanding how ecosystems thrive.

I’ve been reading a small book called The Sound of a Wild Snail Eating. A friend offered to lend it to me, and much to my surprise, I’m finding it fascinating. It’s by a woman with a debilitating illness who describes her growing interest in a snail brought to her on a wild violet plant. As the author learns, there is more to snails than meets the eye. A lot more.

The same may be said of limpets. Christopher Pollon explains why at Hakai Magazine.

“As the ocean temperature rises, it may be the little things that make the biggest difference to the survival and resilience of living things.

“Take the limpet, a tiny snail-like gastropod with a hefty appetite for the minute plants that live in the intertidal — the space between low and high tide. In 2014, Becca Kordas, then a zoology doctoral candidate at the University of British Columbia, tested the effect these creatures have on the ecosystem when exposed to ocean warming. She found that their influence was huge.

“Kordas launched her project by sinking four sets of settlement plates in the intertidal zone of Saltspring Island, British Columbia, about 55 kilometers southwest of Vancouver. For 16 months, Kordas and her colleagues tracked which plants and animals established themselves on the four different types of plots. Kordas controlled the limpets’ access to half of the plates, while they were free to graze on the other half. She also simulated the effects of ocean warming by tinting some of the plates black to attract the sun’s heat.

“By the end of the study, the differences between the four sets of plates were stark. Kordas found that when limpets’ access is restricted, the artificially warmed intertidal ecosystem collapsed — the diversity of life largely replaced by a mat of microalgae. Limpets with access to the plates, however, maintained a healthier ecological community, even in a warming environment.

“What is it about limpets that helps maintain a diverse and complex community, even when their environment warms?

“Kordas says limpets eat huge amounts of microalgae, including microscopic diatoms and the spores of larger algal species. This clears the terrain for a variety of life.

“ ‘When limpets are allowed in, they make space for things like barnacles, and then those barnacles in turn create little condos for other animals to live in,’ she says.

“In a sense, limpets are tiny ecosystem engineers. … The study comes at a critical time for intertidal life in the northeast Pacific Ocean. In this area, the summer low tide typically occurs around noon, which exposes intertidal species to warm summer temperatures. The heat shakes up the intertidal community, but shakes it up more without limpets around.

“The lesson of Kordas’s study, however, is not about limpets per se. It’s about the need to better understand the role of every organism in an ecosystem.”

Hat tip: Pablo Rodas-Martini, @pablorodas, on Twitter.

More here.

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The humble horseshoe crab is a reminder of prehistoric times. Public Radio International’s Living on Earth recently devoted a segment to this curious character.

From the transcript of the show …

Steve Curwood: “For healthy oceans, it’s not enough to protect just the top of the food chain – the cod or halibut or swordfish we eat. The bottom of the food chain is vital too. That could be the plankton or the tiny forage fish eaten by many species – or it could be the extraordinary prehistoric-looking horseshoe crab.

“These helmet-shaped arthropods have been around for millions of years, and up and down the east coast of the US, volunteers come out to count them as the females come ashore to spawn. On Cape Cod, as Karen Zusi reports, scientists and volunteers are tagging and labeling the crabs to help conserve them.”

Karen Zusi: “There are a lot of reasons why someone might appreciate the lowly horseshoe crab. Eel and conch fishermen use them as bait, and medical companies draw blood from the animals. Horseshoe crab blood will clot in the presence of bacteria, so these companies can use the crab’s blood to make sure vaccines and medical implants are free of germs. Their blood is worth sixty thousand dollars a gallon.

“But horseshoe crab populations are dropping. To preserve them, scientists and volunteers on Cape Cod are wading into the water to count and tag the animals.

“Special labels help them keep track [says] Mark Faherty, the science coordinator at Audubon’s Wellfleet Bay Sanctuary. …

“The Massachusetts Audubon Society just recruited graduate student Michael Long to lead their newest horseshoe crab study. With researchers from the University of Massachusetts, he will be tagging the crabs this summer with a telemetry [label], glued onto the crab’s shell.”

Faherty: “My acoustic study is going to be putting on acoustic receivers out in the bay, and acoustic markers on the crabs. The receivers have about a 600-meter detection radius so anytime a crab that’s marked with an acoustic receiver comes within 600 meters of that receiver, it will mark where it is. So based on where each crab pings, you can kind of track its movements around the bay.”

Zusi: “None of this would be possible without the Audubon Society’s volunteers. They come from all walks of life.

“At an Audubon horseshoe crab conference, Long organizes new volunteers to help him count horseshoe crabs on the beach, and Faherty trains them in the basic survey procedures. …

“Once they got down to business, the volunteers were trained to divide the beach into small sections, count the horseshoe crabs, and record all of their information. The volunteers go out to survey when female crabs are coming to lay their eggs in the sand. Males follow to fertilize the eggs after they’re laid.”

Faherty: “The male crabs you quickly learn to recognize because they’re by themselves. They will mate with a model, if you make a model of a horseshoe crab — the males will congregate around it. They’ll spawn. They’ll spawn with your boot. These are just hormonally-charged animals that are ready to mate with anything. Females are not lonely for long in the horseshoe crab world.”

More here on the effort to study and protect horseshoe crabs.

Photo: Peter Massas, Flickr CC BY-SA 2.0
A horseshoe crab floats by the shore on Union Beach in New Jersey. The species is listed as Near Threatened by the International Union for the Conservation of Nature.

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Maria Popova linked to this story on twitter. It’s about how climate change is affecting a way of life for Fiji Islanders.

Meehan Crist writes at the blog Nautil.us, “The day that conservation biologist Joshua Drew, his two students, and I arrive in the Fijian village of Nagigi, the wind is blowing so hard that the coconut palms are bent sideways. ‘Trade winds,’ we are told. And, ‘El Nino. The villagers here also know that climate change is affecting the weather, but their more immediate problem, shared across the Pacific—and, indeed, the world—is an ocean ecosystem sorely depleted by overfishing.

“Nagigi is a village of about 240 people living in tin-roofed wooden homes strung along a sandy coastline. A single paved road runs the length of the village, parallel to the ocean, and along this road are homes clustered by family, painted in cheerful pastels, and connected by well-worn paths through the crab grass. ‘Before,’ said Avisake Nasi, a woman in her late 50s who has been fishing this reef her whole life, ‘you just go out and you find plenty fish. Now, you have to look.’ …

“If pressures mount from too many sides at once—rising ocean temperatures, acidification, pollution, overfishing—the combined pressure will be too much even for Fiji’s remarkably resilient reefs to bear. …

“Conservationists and humanitarian groups have recently united in the call for sustainable resource management, and in this trend, Nagigi is ahead of much of the Western world. Villagers have been discussing how they might use a traditional ban on fishing known as a tabu (tam-bu) to help manage their marine resources in new ways. …

“Drew presents his findings about how fish here are interconnected with other reefs, and how to best protect the species most important to the village in terms of food and income. He talks about how, for the last three years, he has been collecting baseline data about the species present on the reef so that if the village sets up a tabu, its effects can be measured.

“His audience is most interested in what Drew has to say about where to set up a tabu—include the mangroves at the left side of the village shore, because they act as fish nurseries—and for how long—three years would give crucial species enough time to mature and spawn. There has been some talk of a one-year tabu, which would be less of a hardship for villagers who will have to walk a mile or more to reach ocean where they are allowed to fish. But Drew’s data suggest this wouldn’t be long enough to make the sort of difference the village wants to see. ‘I can only offer information,’ Drew says at the end of his presentation, ‘the decision is yours.’ ”

The reporting for Crist’s  story was made possible by a grant from the Mindlin Foundation.

Try to see the related climate-change movie Revolution, which I wrote about here.

Photo: Meehan Crist
The view from Nagigi’s school to the sea, where many locals make their living

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There’s been a lot in the news lately about water shortages in the West. In the search for any help they can get, some concerned citizens are turning to the oft-maligned beaver.

Living on Earth‘s Steve Curwood gets to the bottom of the story with Sarah Koenigsberg, the filmmaker behind The Beaver Believers.

“In the drought-ridden West, some people are partnering with beavers to restore watersheds, where, before trappers arrived, the large rodents once numbered in the millions. Filmmaker Sarah Koenigsberg captures various efforts to reintroduce beavers to their former habitat in her documentary The Beaver Believers and tells host Steve Curwood why beavers are essential for a healthy ecosystem. …

Koenigsberg: We feature the stories of a biologist, a hydrologist, a botanist, an activist, a psychologist and a hairdresser. So these are all very different people who share the common passion of restoring beaver to the west. Some work within the federal agencies, the forest service, others are just average citizens who stumbled upon to the cause accidentally …

“What struck me with all of these beaver believers is that they are working on the problem of water, which is one of the biggest problems of climate change, but is very tangible. They’re working at the level of their own watershed. And while they do work very hard, they’re finding great joy and satisfaction in this work. …

Curwood: There’s a finite supply of water in the drought-ridden American west. Beaver can’t increase that water supply. What can beaver do to help the water situation? …

Koenigsberg: What they do is they redistribute the water that does fall down onto the landscape, so if you picture spring floods — all that water that comes rushing down in March or April just goes straight through the channels and out to the ocean — what beavers do is they almost act like another snowpack reserve, whether it’s rain or snow runoff, all of that water can slow way down behind a beaver pond and then it slowly starts to sink into the ground. It stretches outward making a big recharge of the aquifer and then that water ever so slowly seeps back into the stream throughout the rest of the spring and summer as it’s needed so that we end up with water in our stream systems in July and August when there is no longer rainfall in much of the west.” More here.

Photo: Sarah Koenigsberg
The Beaver Believers live-trapped a beaver family including this kit in Aurora, CO, and relocated them into the forest on a private ranch.

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John sent a link to a story at Business Insider about a science fair project that could have a real impact on the environment.

Jessica Orwig writes, “This 13-year-old is trying to save the world one ecosystem at a time. Chythanya Murali, an eighth grader from Arkansas, has created a safe, effective, non-conventional method to clean oil spills, by harnessing the cleaning properties of bacteria — specifically the enzymes they use to break down oil particles. These enzymes disassemble oil molecules, making way for the bacteria to convert it into harmless compounds. …

“In 2012, a study found a chilling discovery about the oil-cleaning agents dispersed in the Gulf of Mexico after the Deepwater Horizon oil spill of 2010. When combined with the oil itself, the resulting mixture was 52 times more toxic to small animals like plankton than oil alone. …

” ‘My inspiration for this project began [from] the immense damage caused by the BP oil spill in early 2010.’

“To improve oil-cleaning methods, Murali designed a science fair project that explored the different mixtures of oil-eating enzymes and oil-breaking-down bacterias, to see how they effect the marine environment.

” ‘The combination of bio-additive enzymes and oil-degrading bacteria as a novel combination for short and long-term cleaning, and its effect on ecosystems, was not explored before,’ Murali told Business Insider.

“So it only seemed natural to Murali to combine the two and see what happened. She discovered that in a small-scale aquarium, the combination of her chosen oil-cleaning agents could help remove oil while preserving the health of the overall ecosystem, something that some of the oil-cleaning agents we use today cannot achieve.” Read more here.

Kids are going to save the world, I think.

Photo: Chythanya Murali
Chythanya Murali with her science fair poster.

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Ron Finley is a man of humble ambitions. He aims to save the planet, beginning with urban gardeners. I heard an interview with him on America’s Test Kitchen as I was driving home today.

From his website: “Let’s grow this seed of urban guerrilla gardening into a school of nourishment and change. Help spread his dream of edible gardens, one city at a time. …

“In part of this effort, Ron is planning to build an urban garden in South Central LA that will serve as an example of a well-balanced, fruit-and-veggie oasis – called ‘HQ.’ Inspired by the idea of turning unused space such as parkways and vacant lots into fruitful endeavors, this garden and gathering place will be a community hub, where people learn about nutrition and join together to plant, work and unwind. HQ will create a myriad of jobs for local residents, and this plot of land will be a self-sufficient ecosystem.”

It all started, according to Ron, when he “wanted a carrot without toxic ingredients I didn’t know how to spell.” He began to plant food near his house, on a strip by a road.

“The City of Los Angeles owns the ‘parkways,’ the neglected dirt areas next to roads where Ron was planting. He was cited for gardening without a permit.”

After Ron “started a petition with fellow green activists, demanding the right to garden and grow food in his neighborhood … the city backed off.” More here.

When asked on America’s Test Kitchen if his gardens were not just about obesity and healthful eating but also about making neighborhoods more livable, Ron said he wanted to do that for the whole planet.

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I was reading an article by Kathleen Wolf, a social scientist whose “work is based on principles of environmental psychology and focuses on the human dimensions of urban forests and ecosystems.”

The following words struck me: “Interviewees say that merely looking at trees tends to reduce mental and physical stress. A walkable green environment is also thought to increase life satisfaction in later life and even longevity.” Hmm.

So to borrow some words from local honcho H.D. Thoreau, “I went to the woods to see if I could live” longer.

Photos include the Hapgood Wright Town Forest, Joe Pye Weed, an Eastern Tiger Swallowtail, a log like a scaly snake, and various fungi indicating mysteries beneath the surface.

hapgood-wright-town-forest

scaly-snake-log

joe-pye-weed

10-fott-weed-and-swallowtail

fungus

lonely-mushroom

something-is-below-the-surface

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