Saturday, October 5, 2024

Anti-disease forest fungi thrive when they can hear their neighbors: a lesson in diversity

 

There is such value in diversity.

We can take a lesson from a new bit of science that suggests that life performs better when surrounded by its community.

This study found that certain fungi grow faster—many times faster—in an environment that includes sound, even if the species itself does not make sounds.

In the soil, if you were to insert a sensitive microphone, you would pick up the rustle of ants, the scuffling of scurrying beetles, the whisper of larvae, the swooshing of earthworms on their liquid missions and the motion of all the other critters that normally occupy a healthy underground environment.

Fungi don’t have ears, but from this study, clearly they can sense the presence of other creatures by the impacts of their movements, and you could anthropomorphize that they appreciate the company. They certainly behave as if they do.

This particular study was published in the journal Biology Letters. It was reviewed in the New York Times here. 

Wrote Times writer Veronique Greenwood: “Playing sound to Trichoderma harzianum, a green microscopic fungus that defends tree roots from pathogens, led to growth rates seven times as fast as those of fungus grown in the sound of silence. If the laboratory findings can be replicated in nature, then sound could be an unexpected new tool for improving the health of forests, encouraging beneficial microbes to take root and thrive.”

In this case, the researchers just played white noise for the green fungi, and saw dramatic increases in growth compared to the fungi grown in silence.

And here’s a leap.

A totally other piece of science, from the 13 September 2024 issue of Science magazine, expressed concern that the survival of Asian forest trees that contain anti-cancer properties is threatened. People are going into the forest and harvesting the trees to rarity and endangered status.

“Without these trees, cancer patients will lose access to a vital treatment,” wrote authors Gao Chen, Xiang-Hai Cai, Jia Tang, Guillaume Chomicki and Susanne Renner.

In Hawai’i, we have seen the impacts of loss of diversity. If you lose a pollinating bird species, you risk losing the plants they pollinate, and then the insect and fungal communities that rely on those plants. Round and round it goes.

Back to the fungus study, researchers aren’t sure how the fungi are sensing the sound.

“The mechanism responsible for this phenomenon may be fungal mechanoreceptor stimulation and/or potentially a piezoelectric effect; however, further research is required to confirm this hypothesis,” wrote authors Jake M. Robinson, Amy Annells, Christian Cando-Dumancela and Martin F. Breed.

But it was clear that in the presence of sound—all other things being equal—this little green fungus, Trichoderma harzianum, produces lots more biomass and also produces more spores, than in silence.

And they give back to their forest community. These little life forms colonize tree roots, and then protect the trees from disease and rot-causing fungi. They’re so good at it that they’re used as a natural fungicide—applied to leaves, seeds and the soil around valued plants.

Nature’s message is that a diverse community is a far healthier, more productive one.

© Jan TenBruggencate 2024

Monday, September 30, 2024

Navy: Targeting Ka'ula Island bird refuge weekly with bombs and guns would only result in "incidental" take

 The Navy’s new proposal to expand bombing and gunnery practice at Ka’ula Island seems insupportable, both morally and as a matter of federal law.

Here is the Draft Environmental Assessment that includes the Ka’ula impacts.

It expands potential military operations at the tiny island to 55 per year, more than one a week. That is on an island that is a designated state seabird sanctuary (established 1978) and contains endangered and state and federally protected plants and birds, and marine protected species in the nearshore waters.

Ka’ula is one of the four islands of of Kaua’i County (Kaua’i, Ni’ihau, Lehua and Ka’ula). The designated weaponry impact area is 11 acres at the southern end of the 130-acre island.

Ka’ula is well known in Hawaiian history and chant. The bird life there was once so dense that the island was used as an example of overcrowding. 

(Hā’iki Ka’ula I ka ho’okē a na manu. There is no room on Ka’ula, for the birds are crowding. –from ‘Ōlelo No’eau by Mary Pukui.)

It has been bombed since 1952.

The Navy over the years has steadfastly resisted calls to end its bombing, from fishermen, from U.S. Congress members, the U.S. Secretary of the Interior, from the Kaua’i County Board of Supervisors (1961) and Kaua’i County Council (1975), and from federal fisheries and wildlife officials.

And from the State of Hawai’i, whose attorney general in 1978 asserted the island belongs to the state. That conflict over ownership was not resolved, and state officials now say the ownership is contested but no recent efforts to assert state control have been reported.

Weapon strikes are proposed to be limited to the designated 11-acre “impact area.” But that has not always been the case: 1) A 1978 fisherman’s report saw bombs exploding both in the water and among seabirds; 2) The Draft EA says there are likely live munitions on the island outside the impact area; 3) On one occasion in 1965, bombs intended for Ka’ula landed on Ni’ihau, more than 20 miles away.

The new proposal says only inert weapons will be deployed in the future.

The birds and seals of Ka’ula, as well as passing whales and dolphins, are protected by the US. Migratory Bird Treaty Act, the U.S. Marine Mammal Protection Act as well as the island’s designation as a State of Hawai’i bird refuge.

The Draft EA proposes that the impact of bombing, gunnery exercises, helicopter landings and other activities are acceptable. There are Hawaiian cultural sites, including stone temples and habitation sites, but they are outside the designated impact zones and so, “impacts on cultural resources would be less than significant.” (Page 3-86)

The Navy’s legal justification for harming wildlife is contained in a federal law, the 2003 National Defense Authorization Act. It “gave the Secretary of the Interior authority to prescribe regulations to exempt the Armed Forces from the incidental taking of migratory birds during authorized military readiness activities,” the Draft EA says.

Based on that, the Draft EA argues that targeting a wildlife refuge and protected bird nesting site with bombs, shells and landing helicopters would result in takes that are merely incidental. The Draft EA says (Page 3-30) that the Department of Defense has a responsibility to minimize and mitigate its impacts. But it seems at least problematic to argue incidental and minimized when the wildlife refuge is the target.

The Draft EA argues that health, safety and noise are not issues because there are “no human sensitive receptors” nearby. This, of course, does not address the impacts on the health, safety or hearing of protected sooty terns, threatened black-footed albatross or endangered Hawaiian monk seals.

The Navy asserts that it owns Ka’ula. That position has long been challenged by Hawai’i.

The island was set aside by the Territory of Hawaii for use by the U.S. Department of Commerce under the U.S. Lighthouse Service in 1924 as a lighthouse reserve. Commerce conveyed it to the Coast Guard, which operated a navigational light there until 1947, when it was permanently shut down.

Instead of returning the island to the territory, the Coast Guard in 1952 authorized the Navy to conduct bombing exercises, apparently without the authorization of territory. 

Kaua’i County residents began regularly protesting the activity within a few years, at the behest of anglers who said the bombing was impacting birds, which the fishermen depended on to locate schooling fish.

U.S. Rep. Patsy Mink in the early 1960s urged the island’s inclusion in the Hawaiian Islands National Wildlife Refuge, and the Department of Interior started but failed to complete that inclusion.

The Navy rejected the Hawaiian ownership arguments, and in 1965, U.S. Rep. Spark Matsunaga reported that the Coast Guard had transferred its authority over the island to the Navy.

The comment period for this Draft EA is ending. Comments go to pmrf-lbt-ea-comments@us.navy.mil.

© Jan TenBruggencate 2024

Saturday, September 21, 2024

John J. Berger''s new climate book: A comprehensive approach to saving the planet

 The top-of-mind responses to the climate crisis tend to be few and simple.

Use less fossil fuel and switch transportation to electric vehicles, restore forests, recycle, eat less meat.

But a serious response requires a broad rethinking of everything about how we live on the planet. And that’s complex.

John J. Berger’s new book runs through a lot of the approaches that are already underway and makes recommendations for how to proceed. The book is Solving the Climate Crisis: Frontline Reports from the Race to Save the Earth.

Berger is the author of Climate Myths, Beating the Heat, Forests Forever and more. He is a noted environmental writer and climate policy expert, and in his latest book he conducts a comprehensive review of strategies to address our warming climate.

Some possible solutions are underway right now or at least starting. Manufacturing steel that doesn’t depend on massive fossil fuel inputs. Replacing oil-based products with ones made from plants. Electric and fuel cell aircraft.

There’s green concrete, new approaches to recycling, buildings that produce more power than they use, hydrogen cargo trucks and so much more.

There are examples of farmers who have turned problematic fossil-fuel-reliant businesses into thriving green enterprises that restore the soil and entrain carbon. He outlines the benefits of saving and expanding forests.

He reviews some of the geoengineering approaches, like sucking carbon out of the atmosphere, and seeding the skies with compounds that reflect solar radiation.

He takes a realistic look at the issues associated with decarbonizing planet-wide.

There’s clearly lots to be done at the legal, policy and international affairs levels, Berger writes. His to-do list starts with a national recognition that we are in an emergency, and that we need a National Clean Energy Transition Plan.

But it would all be so very costly, right? Maybe not.

“Various studies have found that a clean-energy transition would cost no more than 2 percent of gross domestic product in the United States,” Berger writes. He says he worries about the accuracy of those estimates, but even so, “that’s a pretty good deal, given all the other economic, environmental, and health benefits the United States would also receive.”

Berger’s book is a little overwhelming in its scope, but it’s well-written and anyone interested in how we need to approach this crisis will find lots to chew on. That, and some hope. It may be complicated, but it's possible, is Berger's message.

It does occur to me that, given the topic of the book, an actionable strategy for Berger would have been making the ebook dramatically less expensive than a paper copy of the book, but it’s close to $20 for the electronic version. Here, here, here and here are a some ways to find Solving the Climate Crisis.

© Jan TenBruggencate 2024

Friday, September 13, 2024

Polynesian voyaging driven by resource shortages

 A lot of the research into Polynesian voyaging looks at how it was accomplished and when, but less work has been done on why.

Why would groups of individuals, living in Pacific paradise islands, expend enormous treasure and energy to build great canoes and outfit massive voyaging missions?

The answers are coming.

This blog first looked into the issue in 2007.

That article reviewed a paper that suggested that sea level changes between 4,000 and 6,000 years ago, which created resource shortages, could have launched the Polynesians eastward into the Pacific from the islands near Asia.

And now, there’s new research that suggests a second period of resource shortages 1,000 years ago drove the final exploration phase—the one that led to the inhabitation of Hawai’i, Tahiti, the Marquesas, the Cooks, and eventually Rapa Nui and Aotearoa.

The suggestion is that a huge, multi-century central Pacific drought, from about AD 900 to 1200 drove settled populations out of the central Pacific and led them to locate new homelands that could feed expanding populations.

A team of Hawai’i, United Kingdom and New Zealand researchers in 2020 published a paper saying the signs of that drought can still be located in lake sediments in the Pacific Islands.

Their work answers that nagging question about Pacific voyaging: Why? Why would islanders in rich environments expend vast resources to build and provision voyaging canoes, and then sail into the uncharted ocean?

The paper’s authors are David A. Sear, Melinda S. Allen, Jonathan D. Hassall, Ashley E. Maloney, Peter G. Langdon, Alex E. Morrison, Andrew C. G. Henderson, Helen Mackay, Ian W. Croudace, Charlotte Clarke, Julian P. Sachs, Georgiana Macdonald, Richard C. Chiverrell, Melanie J. Leng, L. M. Cisneros-Dozal, Thierry Fonville, and Emma Pearson. Morrison is a senior archaeologist with Honolulu’s International Archaeology, LLC.

Their research paper, “Human settlement of East Polynesia earlier, incremental, and coincident with prolonged South Pacific drought,” was published in 2020 in the Proceedings of the National Academy of Sciences.

That prolonged drought was detected in sediments in Efate in Vanuatu, ‘Upolu in Samoa, and Atiu in the Southern Cook Islands. Other data from Tahiti and Kiribati also supports the drought hypothesis. It lasted from about AD 900 to AD 1200.

Their suggestion is that exploratory voyagers sailed out initially around 900, that they located islands and brought that information home, but that actual colonization took place generations later.

But once again, the message is that Polynesians voyaged because they had do.

© Jan TenBruggencate 2024

Monday, September 9, 2024

Biological control for Coconut Rhinoceros Beetles?

 Researchers across the world are looking for some kind of bug or disease that can control the coconut rhinoceros beetle, (CRB).

Beetle infestations elsewhere were controlled a few decades ago with the release of a biocontrol virus called Oryctes rhinoceros nudivirus. But in Hawai’i we have a new strain of CRB that seems to be resistant to that virus.

Hawai’i’s biotype of the beetle, also found in Guam and some other Pacific areas, is called CRB-G (clade 1.)

As scientists scramble to look for predators, parasites or disease that might help, research is now focusing on a fungus called Metarhizium, which, when it is effective, kills the CRB beetle larvae and then covers the beetle larva with white fuzzy hairs that later turn green.

There is still more work to be done, but “biopesticides containing Metarhizium spp. are the strongest candidates for inundative biological control against the emerging CRB threat,” said this paper, which will be published in the November 2024 issue of the journal Fungal Biology.

 (Adult CRB, image courtesy Hawaii Department of Agriculture)

That work is being done by researchers from Papua New Guinea, the Solomon Islands, Colombia, and New Zealand, and was funded by the New Zealand Ministry of Foreign Affairs and Trade.  The lead author of that paper is biocontrol researcher Laura Villamizar of AgResearch Ltd. in New Zealand.

One particular isolate of one species of the fungus, Metarhizium majus, appeared to kill CRB (S and G haplotypes) larvae within three to four weeks of application.

“Under field conditions, this isolate demonstrated its ability to infect CRB, dispersal up to 100 m from treated artificial breeding sites, and persistence in soil for at least four months,” the authors said.

That’s all good, but it is early research, and before a biocontrol can be released into a new environment, work needs to be done on what the unwanted impacts might be…like, does this fungus also attack the larvae of valued pollinating insects? 

 

 (Larval CRB, image courtesy Hawaii Department of Agriculture)

Meanwhile, we are approaching the infestation with conventional means.

This giant horned beetle is devastating Hawaiian coconut palms and threatens many other species. Entire coastal palm landscapes on O’ahu, where the beetle was first spotted in 2013, have been destroyed. The creature is actively spreading on other islands, having been identified on Kaua’i, Maui and Hawai’i islands.

The website of Coconut Rhinoceros Beetle Response has extensive information on the threat.

https://www.crbhawaii.org/

The beetle is known commonly as CRB, and science calls it Oryctes rhinoceros. The armored adult is up to two inches long and bores into the hearts of palms to feed on their forming leaves. The beetle larvae are the size of your thumb, and feed on decomposing plant debris—characteristically in compost and debris piles.

In addition to coconuts, they will go after other palms, including the threatened native loulu fan palms, as well as bananas, hala, kalo and sugar cane. Even some hardwood trees have been targeted.

Infected coconut palms are easily recognized by the jagged vee-shaped cuts in their fronds, caused by the feeding beetles when the fronds are still forming.


 (Adult CRB. Note the horn. For more info see https://dlnr.hawaii.gov/hisc/info/invasive-species-profiles/coconut-rhinoceros-beetle/. Image courtesy Hawaii Invasive Species Council.)

Control measures have include putting netting around the palms to block beetle entrance, and using insecticides. But for many palms and in many environments, neither is a feasible solution. (Some of the palms are too tall to realistically treat.) Furthermore, some insecticides can render the coconuts inedible.

Using attractants like pheromones in traps has been another approach. Here is a paper on the pheromone research done on the beetles. https://www.sciencedirect.com/science/article/pii/S0261219423002235

You will see pheromone-infused hanging insect traps at various locations around the affected islands.

 Here’s a trap system folks have used in Guam. https://www.youtube.com/watch?v=47ZQddcvFHk

There is a product called Palm Tree Weevil Killer, PTWK, which claims to be a non-toxic treatment that will kill beetles in the tree. We have not seen independent tests of this system and how well it works. Here are a couple of links: Link 1, Link 2. https://www.hawaiipalmguard.com/uploads/b/58101110-0675-11ef-8f26-0d8569411a43/d9f82fe0-1094-11ef-b96b-3ffeb1dc7cd9.pdf

https://www.alohatreesavers.com/our-product

© Jan TenBruggencate 2024