Philippine Bleeding-heart doves flutter at the brink, but NGOs respond

The 7,100 islands of the Philippine Republic, scattered across the Pacific Ocean and South China Sea, teem with life. The entire nation is a recognized biodiversity hotspot — rated among the 17 most mega-biodiverse countries in the world — with rainforests, volcanic mountain ranges and tropical waters known for species found nowhere else on the planet.

The archipelago’s isolation for millions of years, and its wide variety of habitats has contributed to speciation across the island chain’s 300,000 square kilometers (115,831 square miles) of land area.

Species such as the Philippine eagle (Pithecophaga jefferyi), one of the largest in the world, the Sulu hornbill (Anthracoceros montani), of which fewer than 30 are thought to still exist, and the Philippine Mouse deer (Tragulus nigricans), which stands just seven inches tall, live in forests across the archipelago.

A staggering 40 percent of all bird species found in this island nation are endemic — 226 out of 569 species. Compare that to the level of avian endemism in the United States, which stands at just 7.5 percent, even though the US is more than thirty times the size of the Philippines.

BirdLife International has identified ten Endemic Bird Areas (EBAs) in the Philippines — EBAs being “the most important places for habitat-based conservation of birds” worldwide. Together those ten EBAs encompass almost the whole of the archipelago.

But these species-rich habitats, along with the unique animals that rely on them for survival, are at risk due to a legacy of extreme deforestation that is many decades old: only a fraction of primary Philippines forest is left.

Primary forest on the island of Mindanao. Only a fraction of primary forest remains in the Philippines, and reforestation initiatives using native tree species, known as “rainforestation”, are underway across the Philippines in an effort to restore deforested lands to their former levels of biodiversity. These projects will benefit numerous forest species, like the Bleeding-heart doves, that are found nowhere else in the world. Photo © Bram Demeulemeester
Primary forest on the island of Mindanao. Only a fraction of primary forest remains in the Philippines, and reforestation initiatives using native tree species, known as “rainforestation”, are underway across the Philippines in an effort to restore deforested lands to their former levels of biodiversity. These projects will benefit numerous forest species, like the Bleeding-heart doves, that are found nowhere else in the world. Photo © Bram Demeulemeester

A rare bird gets rarer

Among the most endangered animals are the elusive, shy, ground-dwelling Bleeding-heart doves, named for the colorful red or orange plumage that looks like an open wound blossoming on their white breasts.

All five Bleeding-heart dove species are endemic to the Philippines. Three, found on just a handful of islands, are classified as Critically Endangered by the IUCN. They’ve also been singled out by the Zoological Society of London’s EDGE of Existence program which lists them in the top 100 “Evolutionary Distinct and Globally Endangered” bird species.

Favoring closed canopy lowland forest, and foraging on the forest-floor, Bleeding-hearts are particularly hard hit when the little forest that remains to them is disturbed or cut down.

“Habitat loss from small scale logging, mining and human encroachment (agriculture and residential) are [the] main threats” to the species, revealed Juan Carlos Gonzalez, the Director and Curator for Birds at the Museum of Natural History, University of the Philippines at Los Baños. The birds are also hunted for consumption, trapped accidentally alongside other target species, and captured for sale in the pet trade. This is despite protection under Philippine law for all endangered species, with penalties ranging from fines to several years imprisonment.

For one species, the Sulu Bleeding-heart (Gallicolumba menagei) the chance for survival is slim. Fewer than 50 individuals are thought to remain on the island of Tawitawi. Even though there hasn’t been a confirmed sighting of the species since 1891, reports from the 1990s offer some hope that a small population hangs on.

It’s not only the extreme rarity of G. menagei that makes a comprehensive population assessment difficult. Accessing its most likely habitat to do a thorough survey is hampered by the “risk of bandits and insurgency,” Gonzalez said. Read the full article on Mongabay.

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Dams inevitably result in species decline on reservoir islands

Hydropower development is booming, with controversial projects unfolding across the Americas, Africa, Asia and Europe.

Though often presented as a green renewable energy option, dams can cause a litany of negative impacts: disrupting the downstream flow of nutrients, interrupting aquatic migration routes and harming fisheries. They flood forests, destroy habitat and increase the release of greenhouse gases as vegetation decomposes. Dams also displace human communities — submerging homes and indigenous territories.

A new study adds another impact to the list, one that is widespread but has so far been overlooked by dam developers: “extinction debt” — the incremental but inexorable loss of species and diminishment of biodiversity over time on islands created by reservoirs.

Hydropower developers have long claimed reservoir islands as quality habitat and as viable conservation areas — both assertions are false, according to the new research.

A global evaluation of reservoir islands

The study, led by Isabel Jones at the UK’s Stirling University, collated biodiversity data from 100 studies of reservoir islands — with time since habitat isolation ranging from 1 to 92 years — at 15 dams in North, Central and South America, Europe, and Asia.

In more than 75 percent of cases studied, dams had an overall negative impact on reservoir island species, affecting factors such as species population density, ecological community composition, and species behavior.

Read the full article on Mongabay

Thousand Island Lake in China, the result of a dam built in the 1950s on the Xin'an River, was one of 15 dams worldwide included in a recent study that concluded that reservoir islands should not be counted as conservation areas by developers. Photo by Bryan Ong on Flickr, under a Creative Commons CC BY-NC-ND 2.0 license
Thousand Island Lake in China, the result of a dam built in the 1950s on the Xin’an River, was one of 15 dams worldwide included in a recent study that concluded that reservoir islands should not be counted as conservation areas by developers. Photo by Bryan Ong on Flickr, under a Creative Commons CC BY-NC-ND 2.0 license

Amazonian catfish’s 5,000-mile migration endangered by dams

singular Amazonian catfish is capable of an amazing feat: hidden from human eyes, the species travels vast distances over its lifetime, making a round trip covering more than 8,000 kilometers (nearly 5,000 miles), to return to its natal breeding grounds, a new study confirms.

But even as this record-setting feat — the longest freshwater migration in the world — is scientifically confirmed, the species is threatened by hundreds of planned Amazonian dams.

Brachyplatystoma rousseauxii is a commercially valuable catfish species and an apex predator, growing to 3 meters (more than 9 feet) long. Understanding the migratory patterns of the fish, whose range spans six Amazonian countries, “is paramount for designing adequate conservation and management strategies, especially in view of the current and proposed hydroelectric development throughout the Amazon basin,” the researchers write in the Journal of Applied Ecology.

Observations in the 1990s concerning the size distribution of catfish caught along the length of the Amazon River first led researchers to suggest that long-distance homing migration might be taking place, explained study lead author Fabrice Duponchelle of France’s Institute of Research for Development. Subsequent genetic analyses were consistent with that hypothesis, but still didn’t offer definitive proof.

Intrigued by the possibility that catfish might be homing over such vast distances, Duponchelle employed an innovative technique in the new study to get conclusive evidence: chemical analysis of the otolith, a type of ear bone.

As otoliths grow, their chemical composition changes to reflect the background levels of particular chemical elements found in the environment. Like tree rings, the layers of bone relate to their age: the center, innermost layer of otolith is the oldest, and reflects life as a hatchling; the outer edge is the most recent, and reflects the last stage of the fish’s life.

Read the full article, originally published on Mongabay, here

The giant Amazonian catfish is a valuable commercial species, an apex predator, and the world's long distance freshwater fish migration record holder. Photo courtesy of the USGS Columbia Environmental Research CenterThe giant Amazonian catfish is a valuable commercial species, an apex predator, and the world’s long distance freshwater fish migration record holder. Photo courtesy of the USGS Columbia Environmental Research Center.

Orangutan reintroductions could risk population survival, study warns

An estimated 1,500 orangutans now live in rescue and rehabilitation centers located across Sumatra and Borneo. As habitat loss due to deforestation and forest fires continues, these institutions are struggling to keep up with demand.

Release into the wild is the ultimate, urgent, goal for most of these animals, but a new study warns that there could be serious genetic implications for the offspring of reintroduced animals — and orangutan populations in general — if those rescued from one region are released into a different region.

The study, led by primatologist Graham Banes, examined the genetic consequences when orangutans from different, divergent, subspecies interbreed. Borneo’s three recognized subspecies — from three distinct regions — are thought to have diverged from each other 176,000 years ago, meaning that hybridization between them may result in negative genetic effects. If hybrid offspring reproduce, combinations of genes that were beneficial for one lineage can be disrupted, resulting in poor health and reduced reproductive success, the researcher said. These effects, known as “outbreeding depression,” could threaten the survival of individuals and populations in the long-term.

Read the full article on Mongabay.

A Bornean orangutan in a rehabilitation center in Sabah. Photo by Rhett A. ButlerA Bornean orangutan in a rehabilitation center in Sabah. Photo by Rhett A. Butler

Dams threaten future of Amazonian biodiversity major new study warns

Amazonia’s surge in hydropower development threatens numerous species with extinction, and puts unique habitats at risk, warns a recent study.

River dolphins, giant otters, turtles, fish, birds and monkeys will all have their habitats altered by hydroelectric dams, with some species likely to be completely wiped out, says an international team of biologists that looked at all impacts associated with 191 existing Amazon dams, as well as the 246 dams being planned or under construction.

What’s more, the researchers identified a network of negative interactions between dam construction, mining, climate change, human migration, and biodiversity and ecosystem services which illustrates how impacts can cascade in multiple, devastating ways.

In environmental terms, the most obvious and direct impact of dams reported by the study are on water flow and connectivity. Nutrients that flow downstream from the Andes are interrupted by dams; flood pulses that form a vital part of many species’ lifecycles are modified by the reservoirs and flow patterns that dams create and control; habitat complexity is lost; and species such as river dolphins become isolated in the stretches of river between hydropower developments, which leaves smaller sub-populations vulnerable to decline.

To read the full article, orginally published on Mongabay, click here.

River turtles in Colombia. Turtles, dolphins and otters are among the aquatic species threatened by dam construction, but risks extend to birds, bats and terrestrial animals too. Photo by Rhett A. ButlerRiver turtles in Colombia. Turtles, dolphins and otters are among the aquatic species threatened by dam construction, but risks extend to birds, bats and terrestrial animals too. Photo by Rhett A. Butler

 

Rising CO2 is reducing nutritional value of food, impacting ecosystems

Among the myriad impacts climate change is having on the world, one in particular may come as a surprise: heightened atmospheric CO2 levels might be adversely affecting the nutritional quality of the food you eat. As carbon dioxide in the atmosphere continues to increase, you could end up eating more sugar and less of important minerals such as zinc, magnesium and calcium — without even realizing it. Those effects could also be reverberating up the food chain and altering ecosystems in as yet poorly understood ways.

For plants, a rise in atmospheric carbon dioxide actually boosts productivity by stimulating photosynthesis. They make more carbohydrate and grow larger — seemingly a good thing. But because other nutrients don’t increase and can’t keep pace with the augmented carbohydrate, this potential boon to our food supply isn’t all that it seems: plants end up having a higher carbohydrate to protein ratio, and relatively lower concentrations of minerals.

Put simply: atmospheric carbon dioxide acts as a sort of fertilizer to grow bigger, leafier plants, but those larger broccolis and lettuces actually contain less nutritional value per portion than their predecessors grown in the preindustrial, pre-fossil fuel world.

And that could be a problem for the world’s already malnourished people, for bees seeking protein-rich pollen so they can safely overwinter, and for ecosystems that could be thrown out of balance by changes in plant nutrition.

The human implications of these ongoing changes to our food supply came under the spotlight in April when the US Global Change Research Program (USGCRP) published a major report on the impact of climate change on human health. One of its key findings was that rising carbon dioxide will reduce the nutritional quality of food.

Read the full article on Mongabay

Rice fields in Kashmir, India. Staple crops such as rice and wheat are forecast to become less nutritious as a result of increasing carbon dioxide levels in the atmosphere. Photo courtesy of sandeepachetan.com travel photography on Flickr under CC BY-NC-ND 2.0 licenseRice fields in Kashmir, India. Staple crops such as rice and wheat are forecast to become less nutritious as a result of increasing carbon dioxide levels in the atmosphere. Photo courtesy of sandeepachetan.com travel photography on Flickr under CC BY-NC-ND 2.0 license

Keeping Amazon fish connected is key to their conservation

Imagine a fish isolated in an Amazonian lake — part of the vast freshwater ecosystem of the Amazon basin, an ever-changing network of rivers, lakes and floodplains that extends to 1 million square kilometers (386,102 square miles).

Now imagine that isolated fish as water levels rise during the wet season, and floodplains vanish beneath up to 15 meters (49 feet) of water. The fish — once restricted by the lake’s edge — swims freely into the flooded forest and mingles with others of its kind from elsewhere.

For thousands of years, isolated fish populations across the Amazon have likewise played a game of musical chairs: intermixing between flooding water bodies, migrating short and vast distances between lakes and along river channels, and then as the waters receded, forming new lake and river populations.

This connectivity — with the genetic mixing it affords — is vital for healthy fish populations, but is extremely vulnerable to changes in the annual “flood pulse” that inundates forests.

Read the rest of the article on Mongabay.

A South American Leaf Fish (Monocirrhus polyacanthus). More than 2,000 fish species live in the Amazon, the highest fish biodiversity in the world. That diversity has been greatly enriched due to the periodic isolation and intermixing of freshwater species that occurs across the region. Photo © Rhett A. Butler/MongabayA South American Leaf Fish (Monocirrhus polyacanthus). More than 2,000 fish species live in the Amazon, the highest fish biodiversity in the world. That diversity has been greatly enriched due to the periodic isolation and intermixing of freshwater species that occurs across the region. Photo © Rhett A. Butler/Mongabay