American phainopepla birds, nesting and migration


This November 2013 video from the USA says about itself:

Phainopepla (Phainopepla nitens) is a gorgeous desert bird often seen alone or in a pair at the top of a tree jealously guarded because of ample food supply in the form of mistletoe berries. It eats other berries as well and occasionally will catch an insect, like the flycatcher that it is. The males are glossy black with red eyes and the females are gray. They both have a ragged crest and white wing patches obvious in flight. Here is a rare sight of a flock hanging out at the top of a mesquite tree. Juicy red hackberries were nearby but I didn’t notice any mistletoe yet.

From the American Ornithological Society Publications Office in the USA:

Rare ‘itinerant breeding’ behavior revealed in California bird

October 15, 2019

Reproduction and migration are the two most demanding tasks in a bird’s life, and the vast majority of species separate them into different times of the year. Only two bird species have been shown to undertake what scientists call “itinerant breeding”: nesting in one area, migrating to another region, and nesting again there within the same year, to take advantage of shifting food resources. New research just published in The Auk: Ornithological Advances provides strong evidence that a third bird species takes on this unusual challenge — the Phainopepla, a unique bird found in the southwestern U.S. and the northernmost member of an otherwise tropical family.

Scientists had known for years that some Phainopeplas breed in the desert in spring, where they feed on desert mistletoe berries, and others breed in woodlands in the summer, where a wider range of foods are available — but could these actually be the same birds? To find out, Princeton University’s Daniel Baldassarre, now an Assistant Professor at SUNY Oswego, and his colleagues captured 24 adult Phainopeplas breeding in the Mojave Desert in March and April 2017 and fitted them with tiny GPS tags. To download the GPS data and see where they went, they had to recapture the same birds. Fortunately, five of the 24 birds returned to the same site that fall, and all five tagged birds had migrated to coastal woodland habitats and back in the intervening months — exactly where and when the itinerant breeding hypothesis predicted.

“Seeing the GPS tracks for the first time was amazing, but the biggest thrill for me was re-sighting the first tagged bird that returned to the capture site,” says Baldassarre. “We were a bit unsure how likely they were to come back to the same spot, so to see that a tagged bird had returned was an exhilarating moment. When he hit the net it was like, okay, we’re in business here.”

Circumstantial evidence has long raised suspicions that Phainopeplas might be itinerant breeders. Phainopeplas are vocal mimics, and birdwatchers had observed individual birds in desert habitats mimicking species found in woodland habitats and vice versa. The GPS data from this study still doesn’t completely prove that Phainopeplas are itinerant breeders because the researchers were not able to directly observe any tagged birds nesting in coastal woodlands. However, Baldassarre and his colleagues were able to further support their conclusions with DNA analysis showing that desert breeders and woodland breeders are not genetically different.

“I approached this just thinking about it being a cool species and a rare behavior, but as I started to consider the bigger picture, I realized that the sort of flexibility that itinerant breeding species like this seem to be capable of is also interesting from a climate change perspective,” says Baldassarre. “It suggests that they might be able to deal with climate change better than other birds. They’re highly mobile, they can modulate their physiology to go between migratory and breeding periods quickly, and they can deal with different physical and social environments. It makes this interesting beyond just being a weird bird behavior.”

Why no three-legged animal species?


This March 2018 video says about itself:

3-Legged Deer Is So Grateful His Mom Saved Him | This deer lost a leg when he was 2 days old and could barely walk — but he found a mom who helped him RUN.

This deer has only three legs because of a grave injury. How about animals without such injuries?

From the University of California – Davis in the USA:

Why are there no animal species with three legs?

October 2, 2019

If “Why?” is the first question in science, “Why not?” must be a close second. Sometimes it’s worth thinking about why something does not exist.

Such as a truly three-legged animal. Tracy Thomson, graduate student in the UC Davis Department of Earth and Planetary Sciences, has been pondering the non-existence of tripeds. He recently published an essay on it, “Three-Legged Locomotion and the Constraints on Limb Number: Why Tripeds Don’t Have a Leg to Stand On” in BioEssays.

Thomson got the idea after taking a graduate class on evolution with UC Davis paleontologist Geerat Vermeij, who challenged the students to come up with a “forbidden phenotype:” an animal or plant that does not and cannot exist.

Thomson points out that there are lots of animals that use a tripod stance to rest. Meerkats in an upright stance rest on their tail and rear feet; woodpeckers use tail feathers to brace themselves against a tree-trunk.

A tripod stance does not require any energy to be stable, Thomson noted. Unlike, for example, standing upright on two feet, which does require some muscle work as well as relatively large feet.

Three-limbed movement is less common. Insects, which of course have six legs, have a mode of movement where their legs move in sets of three: two legs on one side and one on the opposite side are on the ground, with the opposite legs moving, at any time. This is called the “alternating tripod” gait.

Gripping tails and beaks

Many tree-dwelling animals use their tails for additional gripping, although they may be moving with all four of their limbs as well. Parrots are quite tripedal, using their strong, flexible beak as an additional grip to maneuver in tree branches.

Long rear feet make it difficult for kangaroos to “walk” like other mammals. Instead, they use their strong tail and front limbs to push the rear feet off the ground and forwards while grazing.

Given that three-limbed movement does seems to work for some animals, why are there no animals with three legs? That might go back a long, long way, Thomson said.

“Almost all animals are bilateral,” he said. The code for having two sides to everything seems to have got embedded in our DNA very early in the evolution of life — perhaps before appendages like legs, fins or flippers even evolved. Once that trait for bilateral symmetry was baked in, it was hard to change.

With our built-in bias to two-handedness, it can be hard to figure out how a truly three-legged animal would work — although that has not stopped science fiction writers from imagining them. Perhaps trilateral life has evolved on Enceladus or Alpha Centauri (or Mars!) and has as much difficulty thinking about two-limbed locomotion as we do thinking about three.

This kind of thought experiment is useful for developing our ideas about evolution, Thomson said.

“If we’re trying to understand evolution as a process we need to understand what it can and can’t do,” he said.

Californian worm species with three sexes discovery


This April 2018 video from the USA says about itself:

Mono Lake is a striking blue oasis in the eastern California surrounded by desert peaks, volcanoes, and the Sierra Nevada. Strange tufa tower formations and saline waters lie at the edge of mountain streams and snow-capped mountains. Millions of birds, trillions of brine shrimp, and countless alkali flies contribute to one of the most productive lake ecosystems on the planet.

In 1941, the Los Angeles Department of Water & Power began the Mono Lake Storydiverting water from Mono Lake’s tributary streams, sending it 350 miles south to meet the growing water demands of Los Angeles. Deprived of its freshwater sources, the lake dropped 45 vertical feet. Its salinity doubled and the ecosystem approached collapse.

Researchers, students, bird freaks, and an engaged public took notice and formed the Mono Lake Committee. Sixteen Years later, this dedicated grassroots movement altered history by protecting Mono Lake, securing new water solutions for Los Angeles, and transforming water law in California. The Mono Lake Story is about changing values and balancing those values against difficult odds. It’s about how a small and dedicated group of individuals, trying to do the right thing, can grow into an effective coalition of organizations, agencies, and public support that triumph over fundamental environmental challenges.

The Mono Lake story is a rare environmental success that can inspire and inform the environmental challenges of our time.

From the California Institute of Technology in the USA:

Otherworldly worms with three sexes discovered in Mono Lake

Eight species of nematode discovered in the lake’s harsh conditions

September 26, 2019

Summary: The extreme environment of Mono Lake was thought to only house two species of animals — until now.

Caltech scientists have discovered a new species of worm thriving in the extreme environment of Mono Lake. This new species, temporarily dubbed Auanema sp., has three different sexes, can survive 500 times the lethal human dose of arsenic, and carries its young inside its body like a kangaroo.

Mono Lake, located in the Eastern Sierras of California, is three times as salty as the ocean and has an alkaline pH of 10. Before this study, only two other species (other than bacteria and algae) were known to live in the lake — brine shrimp and diving flies. In this new work, the team discovered eight more species, all belonging to a class of microscopic worms called nematodes, thriving in and around Mono Lake.

The work was done primarily in the laboratory of Paul Sternberg, Bren Professor of Biology. A paper describing the research appears online on September 26 in the journal Current Biology.

The Sternberg laboratory has had a long interest in nematodes, particularly Caenorhabditis elegans, which uses only 300 neurons to exhibit complex behaviors, such as sleeping, learning, smelling, and moving. That simplicity makes it a useful model organism with which to study fundamental neuroscience questions. Importantly, C. elegans can easily thrive in the laboratory under normal room temperatures and pressures.

As nematodes are considered the most abundant type of animal on the planet, former Sternberg lab graduate students Pei-Yin Shih (PhD ’19) and James Siho Lee (PhD ’19) thought they might find them in the harsh environment of Mono Lake. The eight species they found are diverse, ranging from benign microbe-grazers to parasites and predators. Importantly, all are resilient to the arsenic-laden conditions in the lake and are thus considered extremophiles — organisms that thrive in conditions unsuitable for most life forms.

When comparing the new Auanema species to sister species in the same genus, the researchers found that the similar species also demonstrated high arsenic resistance, even though they do not live in environments with high arsenic levels. In another surprising discovery, Auanema sp. itself was found to be able to thrive in the laboratory under normal, non-extreme conditions. Only a few known extremophiles in the world can be studied in a laboratory setting.

This suggests that nematodes may have a genetic predisposition for resiliency and flexibility in adapting to harsh and benign environments alike.

“Extremophiles can teach us so much about innovative strategies for dealing with stress,” says Shih. “Our study shows we still have much to learn about how these 1000-celled animals have mastered survival in extreme environments.”

The researchers plan to determine if there are particular biochemical and genetic factors that enable nematodes’ success and to sequence the genome of Auanema sp. to look for genes that may enable arsenic resistance. Arsenic-contaminated drinking water is a major global health concern; understanding how eukaryotes like nematodes deal with arsenic will help answer questions about how the toxin moves through and affects cells and bodies.

But beyond human health, studying extreme species like the nematodes of Mono Lake contributes to a bigger, global picture of the planet, says Lee.

“It’s tremendously important that we appreciate and develop a curiosity for biodiversity,” he adds, noting that the team had to receive special permits for their field work at the lake. “The next innovation for biotechnology could be out there in the wild. A new biodegradable sunscreen, for example, was discovered from extremophilic bacteria and algae. We have to protect and responsibly utilize wildlife.”

The paper is titled, “Newly Identified Nematodes from Mono Lake Exhibit Extreme Arsenic Resistance.” Shih and Lee are co-first authors on the study; Shih is now a postdoctoral fellow at Columbia University and Lee is now a postdoctoral fellow at The Rockefeller University. In addition to Shih, Lee, and Sternberg, other co-authors are Ryoji Shinya of Meiji University in Japan, Natsumi Kanzaki of the Kansai Research Center in Japan, Andre Pires da Silva of the University of Warwick in the UK, former Caltech Summer Undergraduate Research Fellow student Jean Marie Badroos now of UC Berkeley, and Elizabeth Goetz and Amir Sapir of the University of Haifa in Israel. Funding was provided by the Amgen Scholars Program, the Leverhulme Trust, and the Howard Hughes Medical Institute.

Forests of California, USA defended


This 21 September 2o19 video from the USA says about itself:

A New Generation of Activists Put Their Bodies on the Line to Defend California’s Forests

The deforestation of the Amazon is recognized around the world as a catastrophe for global climate change. Far less recognized is the threat of deforestation of temperate rainforests, such as the enormous coastal forest that stretches from Northern California to Alaska. By some estimates, temperate rainforests sequester from 2 to 7 times as much carbon per acre as tropical rainforests like the Amazon. Keeping these ecosystems healthy and intact is an imperative part of avoiding a future of cataclysmic global warming.

In Humboldt County, California, activists have been fighting for decades to preserve the forests and have embraced direct action tactics aimed at physically preventing logging companies from felling redwoods, Douglas firs, madrones, and other trees by using their own bodies as blockades. They have built platforms 100 feet in the air in the canopies of trees and lived on them for weeks, months, or even years at a time. They have erected tripods to block logging roads and sat atop them, so that if the tripods were dismantled, they would face injury or death. They have chained themselves to bulldozers and other earth-moving equipment.

The tradition in the region stretches back to the legendary activism of Judi Bari, Julia “Butterfly” Hill, and many less well-known but no less committed radical environmental activists. Today, a new generation of activists has taken up the cause, using direct action tactics to confront logging companies such as Sierra Pacific Industries, Green Diamond Resource Company, and the Humboldt Redwood Company (the latter is the company that used to be Pacific Lumber, which was the target of Earth First!’s activism in the “Timber Wars” of the 1980s and ’90s). Our short documentary, produced by Adamant Media, tells their story.

Note: We were not able to secure interviews with spokespersons from Green Diamond Resource Company and Humboldt Redwood Company in time for publication, but a representative of the Humboldt Redwood Company claimed that its “hack and squirt” technique for clearing the forest of hardwood trees is environmentally sustainable and that the company seeks to eventually phase out the use of chemical herbicides. The representative further stated that the company cut the resupply lines of a tree-sitting activist only in order to prevent supporters on the ground from sending materials that presented fire dangers up into the tree.

This story is part of Covering Climate Now, a global collaboration of more than 250 news outlets that aims to strengthen coverage of the climate crisis.

Green sturgeon and salmon in California, USA


This June 2010 video from the USA says about itself:

Yurok Tribal Fisheries Program biologist Barry McCovey and technician Rocky Erickson capture and surgically implant an acoustic transmitter into a Green Sturgeon at the Klamath River in northern California.

From the University of California – Santa Cruz in the USA:

Shasta dam releases can be managed to benefit both salmon and sturgeon

August 20, 2019

Cold water released from Lake Shasta into the Sacramento River to benefit endangered salmon can be detrimental to young green sturgeon, a threatened species adapted to warmer water. But scientists at UC Santa Cruz and the National Marine Fisheries Service have found a way to minimize this apparent conflict through a water management strategy that benefits both species, while also meeting the needs of agricultural water users downstream.

Releases of cold water during the spring and summer create favorable spawning conditions in the Sacramento River for the endangered winter-run chinook salmon, which were cut off from their historical spawning grounds at higher elevations by the construction of Shasta Dam. Salmon eggs require cold water temperatures to survive, but juvenile green sturgeon need the lower flows and warmer temperatures typical of the main stem of the Sacramento River to grow and thrive.

The researchers used statistical modeling to see if there is an optimal management scenario that can meet the needs of both species along with those of downstream water users. Their results, published August 20 in the Journal of Applied Ecology, show that dam releases can be managed to achieve all three objectives in all but the most severe drought years.

“It’s a win-win-win here in the sense that we’re not giving up anything to get an improvement for the green sturgeon,” said Eric Palkovacs, associate professor of ecology and evolutionary biology at UC Santa Cruz and senior author of the paper. “Currently, the primary management objectives are keeping it cold for the salmon eggs and delivering enough water downstream. As a result, we’ve been refrigerating the river in regions where historically the green sturgeon have been spawning.”

First author Liam Zarri conducted the study for his UCSC master’s thesis, working with Palkovacs and coauthors Eric Danner and Miles Daniels at the National Marine Fisheries Service laboratory in Santa Cruz. Zarri found that discharge rates and water temperatures strongly influence the body condition of larval green sturgeon. In years with high discharges of cold water, egg survival for winter-run chinook salmon was high but the condition of juvenile green sturgeon was poor. In drought years, however, with low flows and warmer water, green sturgeon did well while salmon egg survival was low. The sturgeon larvae seem to be especially sensitive to high discharges, which affect their swimming ability and availability of prey.

The key to meeting the needs of both species, Zarri said, is that they spawn at slightly different times of the year. “We’re able to suggest a management scenario which uses the differential timing of spawning in these two species. When they overlap, our model gives us the ideal temperature and flow for when both species are present,” he said.

Zarri noted that the dam releases can draw either cold water from the bottom of the lake or warmer water from closer to the surface. Under the optimal management scenario proposed in the paper, low flows of warmer water can be released early in the season (April and May) when only green sturgeon are spawning and demand for water for agriculture has not yet ramped up. Late in the season (July to November), high flows of cold water can be released to benefit salmon and meet agricultural water needs.

The overlap period in June and early July, when both salmon and sturgeon are present in the part of the river most affected by the dam releases, is more complicated. That’s where the statistical modeling approach, which takes into account the needs of both species, provides the ideal conditions of temperature and water flow that dam managers can aim for to ensure that the river is not too warm for salmon or too cold and fast for sturgeon.

“Under the current management, there is quite a long period of cold water releases starting very early in the season before the chinook salmon have really started showing up in earnest. We’re saying that you can wait until the green sturgeon have matured and moved out of the system,” Palkovacs said. “That has a side benefit in drought years, when limiting those early releases saves water for later in the year when it’s more valuable, both for salmon and for downstream water demand.”

Palkovacs noted that other native species in the river, including spring and fall runs of salmon, are probably also being affected by the cold water releases. At this point, however, the researchers did not have enough information about other species to include them in their analysis.

This work was funded by NOAA and the U.S. Bureau of Reclamation.