Bleached coral off the coast of Panama.

A new study by Florida State University and Smithsonian Institution biologists shows that bleaching events brought on by rising sea temperatures are having a detrimental long-term impact on coral.

Bleaching—a process where high water temperatures or UV light stresses the coral to the point where it loses its symbiotic algal partners that provides the coral with color—is also affecting the long-term fertility of the coral the scientists reveal in the latest issue of Marine Ecology Progress Series.

Don Levitan and William Boudreau of Florida State University; Javier Jara from the Smithsonian Tropical Research Institute in Panama, and Nancy Knowlton from the Smithsonian’s National Museum of Natural History are co-authors of the study.

Most corals reproduce by releasing sperm and eggs into the ocean during brief annual spawning events. The chance of sperm finding and fertilizing an egg depends on corals spawning in close proximity and in synchrony with each other.

In a study of the corals that build the major framework of Caribbean coral reefs, the team found that the species living in shallower water experienced near total reproductive failure, while the species living in deeper water were about half as likely to spawn.

“The remarkable finding from this study was that the reduction in spawning persisted for three additional years, long after the corals had regained their symbiotic partners and regained their normal appearance,” says Levitan, chair of the Department of Biological Sciences at Florida State. “Even corals that didn’t bleach aren’t reproducing at the levels they should.”

The worldwide decrease in coral abundance in combination with long-term reductions in spawning and reproduction following bleaching events put reef- building corals in a difficult situation. Eggs might be released, but never fertilized. And that could have a major impact on the ecosystem at large.

Levitan and other researchers been studying coral just off the coast of Panama since 1996. Since then, those corals have been exposed to two bleaching events. On average, it takes coral three to four years to recover from bleaching.

“Even if we can fix what’s killing these corals, it’s going to be hard for coral populations to recover, because the surviving corals might not successfully produce enough offspring to repopulate reefs,” Levitan said.

Coral reefs provide protection and shelter for many different species of fish. Without the reefs, certain fish are left homeless and without an area to reproduce. They also protect coastlines from large waves and flooding, a major issue in areas that are prone to tropical storms or hurricanes.

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Map of known dead zones (white dots) and predicted changes in annual air temperature for 2080-2099 versus 1980-1999. The air temperature predictions are based on a “middle-of-the-road” scenario of fossil fuel use. (Credit: Keryn Gedan and Andrew Altieri)

A full 94 percent of the dead zones in the world’s oceans lie in regions expected to warm at least 2 degrees Celsius by the century’s end according to a new report from the Smithsonian Tropical Research Institute and the Smithsonian Environmental Research Center published Nov. 10 in Global Change Biology. The paper states that warmer waters—mixed with other climate change factors—make for a dangerous cocktail that can expand dead zones.

Dead zones form in waters where oxygen plummets to levels too low for fish, crabs or other animals to survive. In deeper waters, dead zones may last for months, as with the annual summer dead zone in the Chesapeake Bay. Temporary dead zones may occur in shallow waters at night. The largest dead zones in the Gulf of Mexico and Baltic Sea can cover more than 20,000 square miles of the sea floor. The number of dead zones across the world is growing exponentially, doubling each decade since the 1960s.

“They’re having a big impact on life in the coastal zone worldwide,” said Keryn Gedan, a co-author and marine ecologist at the Smithsonian Environmental Research Center and the University of Maryland. “A lot of people live on the coast, and they’re experiencing more fish kills and more harmful algal blooms. These are effects of dead zones that have an impact on our lives.”

Dead juvenile menhaden fish (Brevoortia tyrannus) float to the surface during a dead zone event in Narragansett Bay, Rhode Island. (Credit: Andrew Altieri/Smithsonian Tropical Research Institute)

The main culprit is massive algal blooms, which pull oxygen from the water when they respire or decompose. Algal blooms form from excess runoff of nutrients like nitrogen and phosphorus. But climate change could exacerbate the problem.

Warmer waters hold less oxygen, the authors explain in the paper, enabling dead zones to form more easily. When temperatures rise, animals like crabs, fish and oysters need even more oxygen, which the ocean is less able to provide.

“Our study is the first to consider more than a dozen direct and indirect effects of climate change on dead zones, and suggests that we’ve underestimated its contribution to the growing dead zone problem and impacts on marine life,” said Andrew Altieri, the study’s lead author and ecologist at the Smithsonian Tropical Research Institute.

Altieri and Gedan looked at a database of more than 400 dead zones around the world and then overlaid them on a map of the annual temperature anomalies expected to occur in each region. Under a middle-of-the-road scenario, 94 percent of dead zones are in areas expected to warm by 2 degrees C or more by 2099. Then they did a thorough literature review, synthesizing information from many fields to predict how the various effects of climate change could work together to impact dead zones.

Piles of mussels (“Mytilus edulis”) washed onto a beach after a dead zone event in Narragansett Bay, Rhode Island. Besides providing food and habitat for other creatures, mussels can also filter water. When mussels die, the bay loses its ability to clear water of phytoplankton, increasing the risk of future dead zones. (Credit: Andrew Altieri/Smithsonian Tropical Research Institute)

Besides making it harder for water to hold oxygen, rising temperatures stifle ocean mixing that can keep dead zones in check. Dead zones near the bottom can dissipate if waters from the surface sink, injecting them with fresh oxygen from above. But since warmer waters float, this life-giving conveyor belt grinds to a halt.

Other factors besides temperature come into play. Sea-level rise leads to the expansion of bays and estuaries, raising the overall volume of water susceptible to low oxygen. The same rising waters also can destroy wetlands. Wetlands are one of the best defenses against dead zones because they filter out excess nutrient pollution that feeds massive algal blooms.

Shifting ocean currents could further expand dead zones by flooding them with more oxygen-starved waters. This is already happening in the St. Lawrence Estuary where cold, oxygen-rich waters from northern Canada have declined and are being replaced by warmer, oxygen-poor waters from the central North Atlantic.

Altieri and Gedan uncovered just one possible positive impact of rising temperatures: Since animal metabolism spikes under higher temperatures, tiny crustaceans, like copepods, and other zooplankton could eat up the algal blooms that create dead zones in the first place. “We do see some cases where algal blooms are smaller in warmer years, because the grazers are able to control algae better,” Gedan said. But, she added, it is unclear how that will interact with the other climate change impacts they have witnessed.

Altieri suggests there is an important lesson to learn from their study: “There is a lot of inertia when it comes to global climate change, but we can counteract climate effects on dead zones through local control of nutrient pollution.”

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The shell of this nautilus at the Smithsonian’s National Zoo clearly shows the deformity–area characterized by black bands–that started after it began living in an aquarium. (Photo by Mehgan Murphy)

In the wild, wide milk chocolate-brown stripes adorn the beautiful smooth, white shells of the chambered nautilus, a deep-diving mollusk from the Indo-Pacific Ocean. But when placed in an aquarium, the new surfaces of shell these animals produce become thick, rough and stripped with a black substance. Why this ugly deformity occurs is a mystery that aquarists have puzzled over since the 1970s.

“We wondered if they are not getting something in their diet in aquaria or if something in the water is not available to them,” explains Alan Peters, a curator at the Smithsonian’s National Zoo in Washington, D.C.  “Aquarists have long known that in an aquarium the normal pattern of the nautilus’ shell never fully returns.”

This scanning electron microscope image (top) shows the orderly crystalline structure in a wild formed Nautilus. The disorderly crystalline structure of the aquarium-formed shell is at bottom.

Calling upon a variety of scientific techniques, including stable isotope mass spectronomy, scanning electron microscopy, micro X-ray fluorescence and X-ray diffraction, a team of researchers including Peters recently took a close look at this shell deformity. Using the shells of nautiluses that had first lived in the ocean and then been placed in an aquarium they carefully examined and compared the chemical and physical structure of portions of both the old and new shell.

What they first found under a scanning electron microscope was that the crystalline structure of aquarium-formed shell was less ordered, poorly defined and without a clearly defined shape or form.

Next, chemical analysis revealed that the black deposits in aquarium-produced shell contain excess amounts of copper, zinc and bromide and decreased amounts of calcium and magnesium.

High amounts of copper, zinc and bromide “point to the role that proteins play in the construction of the shell,” and do not appear related to diet or tank-water chemistry, Peters and colleagues write in a recent paper in the journal Zoo Biology.

When a nautilus is removed from its natural environment and placed in an aquarium, it experiences “environmental stress such as changed pressure, temperature and ultraviolet light patterns.” That may trigger an attempt to reinforce their aquarium-formed shell, compensating for a weakened crystalline structure.

The shell of this aquarium-living nautilus clearly shows the difference between its wild-produced and captive-produced shell. (Flickr photo by Michael Bentley)

In the end, the scientists were unable to reach a conclusion as to just what what causes a nautilus shell to deform in an aquarium. “We have all kinds of theories,” Peters says “but so far we are unable to confirm any of them.” The researchers next plan to conduct experiments measuring the impact of temperature and light on the production of black areas of shell, as well as the function of proteins in wild vs. captive  shell production.

Nautiluses appeared on earth about 500 million years ago during the Cambrian Explosion—they were jet-propelling themselves through ancient seas 265 million years before dinosaurs inhabited the Earth. They have remained mostly unchanged for millions of years.

Today the animals are characterized by experts as being on the “knife-edge” of extinction, overfished across their range because of their beautiful shells. A recent survey by the U.S. Fish and Wildlife Service disclosed that the U.S. imports some 100,000 nautilus shells each year. Their numbers in the Philippines have dropped by 80 percent since the 1980s. International trade sanctions against the capture and trade of the nautilus are virtually nonexistent.

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Left-handed snails, giant wombats, spiny trilobites, zombie ants, glyptodonts…these are a few of the fascinating animals and plants whose fossils spring to life across the pages of A History of Life in 100 Fossils, a new offering from Smithsonian Books.

Selected from the collections of the Smithsonian’s National Museum of Natural History in Washington, D.C., and the Natural History Museum in London, each fossil is beautifully photographed and explored in-depth with a captivating description of its importance to the story of evolution and life on Earth. Organized chronologically from the Precambrian through the Paleozoic, Mesozoic and Cenozoic eras, the book reveals the remarkable and persistent unfolding of fantastic life forms across the Earth as revealed in the fossil record.

Co-authors Aaron O’Dea of the Smithsonian Tropical Research Institute in Panama and Paul Taylor of the Natural History Museum in London carefully compiled the images in this book from hundreds of possibilities.

One of the first and oldest entries, a 3.5 billion-year-old rusty red stromatolite fossil, is arguably the most important. Dominating the world’s oceans for a staggering 3 billion years, stromatolites eventually filled the atmosphere with enough oxygen to enable the rise of complex oxygen-breathing organisms.

Aaron O’Dea

The oddest entry is a spiral bezoar (fossilized feces) recovered from ancient sea sediments and which once was imbedded in the intestine of a prehistoric shark.

Most touching: The Laetoli footprints from Tanzania, left in a matter of seconds some 3.5 million years ago, appear to show the path of a small family of early hominins, Australopithecus afarensis, wandering through a volcano’s devastation.

Steller’s sea cow wins as the saddest entry, “a sad tale of a once magnificent beast driven to extinction by hunting,” O’Dea, a paleobiologist, says. “Without its fossil record we would have had no idea that the animal was naturally widely abundant until a few thousand years of hunting whittled them away to almost nothing.”

“Onychonycteris finneyi,” a remarkably complete bat fossil found in 52-million-year-old lake sediments in Wyoming.

Other fossils examined include Cambrian worms from China that provide a window on early animal life in the sea, ancient insects encapsulated in amber, the first fossil bird Archaeopteryx and the last ancestor of humankind.

Writing A History of Life in 100 Fossils with Taylor “was a fantastic experience,” O’Dea observes in his blog. “Researching in detail about fossil groups I had previously paid little attention to, spinning evolutionary tales with a single slab of rock and crafting them in a way that could be accessible to all. As I wrote I tried to weave all the big biological themes into the book; natural selection, convergent evolution, sexual selection, extinction, the origin of life and even parasitism.”

A History of Life in 100 Fossils is brimming with epic tales of survival and migration, evolution and destruction once concealed in the buried remains of animals and plants that lived long ago.

Available from Smithsonian Books October 14.

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(Photo: Patrick Kelley/U.S. Coast Guard)

Archived feed of this symposium »

The world is changing at a rapid pace. Scientists have documented significant changes during the past century in climate, land-use and biodiversity that are unprecedented over the past thousand years. To examine this phenomenon through the lenses of science, society and culture, the Smithsonian is hosting a symposium “The Anthropocene: Planet Earth in the Age of Humans,” was held Thursday, Oct. 11, from 9:15 a.m. to 6:30 p.m. in Baird Auditorium, Smithsonian’s National Museum of Natural History.

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The colorful Indo Pacific squat lobster “Allogalathea elegans.” (Photo by T. Y. Chan and C. W. Lin)

Their flavor is a unique blend of lobster and shrimp say lovers of the savory South American crustaceans called “langostinos.” Simmered with garlic, lime juice, peppers and onions, langostinos are enjoyed in dishes ranging from linguini to tacos.

Smithsonian researcher Patricia Cabezas knows langostinos by a less-appetizing name: squat lobsters, crustaceans more closely related to hermit crabs than the familiar grocery store-tank lobsters. The squat lobsters netted and eaten by humans in South America represent the tip of the iceberg in terms of the remarkable diversity of these animals: more than 1,000 species are known worldwide.

The squat lobster “Munida thoe” lives in the Southwest Pacific near New Caledonia. (Photo by T. Y. Chan and C. W. Lin)

While virtually unknown to the general public, on the ocean floor squat lobsters rule. “They are extremely conspicuous and abundant in the deep sea and shallow waters and exhibit a rainbow of breathtaking colors,” Cabezas says. Their ‘tail’ or abdomen, is permanently tucked beneath their body—thus their name. They live at varying depths from coral reefs to deep hydrothermal vents.

In recent years Cabezas has discovered and named two new genera and 29 new species of squat lobsters, most recently Paramunida haigae from the Central Pacific Ocean. To name a new species Cabezas carefully measures and compares a specimen’s antennae, carapace spines and other body parts with the body characteristics of known species. Then, using photographs and illustrations, she writes a detailed description of the new species that is peer reviewed and published in a scientific journal.

Her office at the Smithsonian’s Museum Support Center in Suitland, Md., is in close proximity to the wet collections of the National Museum of Natural History’s Department of Invertebrate Zoology, which holds hundreds of thousands of crustacean specimens available for study.

Patricia Cabezas holds a jar of squat lobsters in the wet collections of the Department of Invertebrate Zoology, National Museum of Natural History. The collection is housed at the Smithsonian’s Museum Support Center, Suitland, Md. (John Barrat photo)

Squat lobsters range in size from a few tenths of an inch to as large as your palm and “are really, really challenging to study because their morphological differences are very subtle. It is very, very tough,” describing and naming a new species, Cabezas explains.

Despite the difficulty, scientists name dozens of new species every year and Cabezas is certain many undescribed species still lurk in the ocean depths. The well-known yeti crab discovered in the South Pacific in 2005 with its long furry arms, for example, is a squat lobster.

“Species discovery for squat lobsters will be a never-ending story,” she says. “There are so many places that haven’t been sampled. They are absolutely everywhere. The Indian Ocean between Indonesia and India is a mystery,” Cabezas says. “As soon as we start collecting specimens from there, I can tell you we’re going to see a bunch more new squat lobster species.”

Squat lobster specimens in the wet collections of the Department of Invertebrate Zoology, National Museum of Natural History. Preserved in alcohol they loose their color.

Many squat lobster species are native to archipelagos or restricted geographic areas. Most are scavengers, eating anything that floats by or drops to the ocean floor. Some feed on small crustaceans and octopods in the water column.

Squat lobsters are classified in two large families: Chirostyloidea and Galatheoidea. Chirostylids are mainly deep water animals and include species characterized by slender and elongated appendages that are commonly found perching on corals. Galatheids make up roughly 75 percent of squat lobster diversity and are found from tropical shallow-water reefs to abyssal depths.

The shallow-water squat lobster “Macrothea bochardi” from the Indian Ocean off the coast of Southeast Africa. (Photo by T. Y. Chan and C. W. Lin)

Collecting, finding and describing new species of squat lobsters is important, Cabezas adds, because “today we are destroying biodiversity, so we have to describe new species as fast as we can or we may destroy something that we never knew existed.” A basic understanding of the diversity of life increases our opportunities for medical discoveries, economic development and the ability to face environmental challenges such as climate change, Cabezas says. “Look at the sponges, for example. Basic research in sponges has provided us with different new chemicals that apparently can help us fight cancer.”

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A predator crown-of-thorns sea star eats an undefended coral, leaving visible white scars of exposed coral skeleton where the tissue has been removed. (Photo by Jenna Moore)

Imagine sitting down at your favorite restaurant when something under the table begins painfully pinching and snipping at your toes. This is basically how T. flavopunctata crabs in French Polynesia defend their coral hosts from the large and lethal Crown-of-Thorns sea star (Acanthaster planci).

Long before a sea star can begin eating a coral, T. flavopunctata living inside the coral emerge and begin pinching the sea star’s tube-like feet, shaking them and nipping them off. “Basically, they annoy the sea star until it goes away,” says Jenna Moore from the Florida Museum of Natural History, who is also a predoctoral fellow at the Smithsonian’s Natural Museum of Natural History.

When scientists removed the largest species of the guard-crabs, “Trapezia flavopunctata” (shown here), from the path of an army of predator sea stars, the effects were dramatic; corals without guard-crabs, or with other species of guard-crab, were eaten—usually overnight. (Photo courtesy Seabird McKeon)

The crabs are not only defending their home, the coral is also their restaurant. Coral keep T. flavopunctata crabs and other crab species happy with fatty deposits they produce in the tips of their tentacles that the crabs snip off and eat.

In a recent study in French Polynesia, Moore and Seabird McKeon, a scientist at the Smithsonian’s Marine Station in Fort Pierce, Florida, learned that to stay safe and sound, a coral needs a variety of crabs of various species and sizes to defend it against predators both large and small. Details from this study are published in the Sept. 30 issue of the open-access journal, PeerJ.

“We found that diversity in both species and size of coral guard-crabs is needed to adequately fend off coral predators,” McKeon says. “It is an example of how biodiversity is crucial to conserving reef environments and the essential resources they provide for thousands of species, including humans.”

A crab inside its coral home. Coral guard-crabs across the Indo-Pacific live in and fiercely defend coral reefs against predators in exchange for shelter and nutrition that the corals secrete. (Image copyright David Liittschwager)

For example, while crabs of the species T. flavopunctata were staunch defenders against Crown of Thorns sea stars, they ignore a much smaller threat, the sea snail Drupella. Enter the smaller guard crab species T. serenei, which takes up the fight against encroaching snails. McKeon and Moore studied three species of crabs known to protect coral in a series of experiments to examine the effectiveness of different species and various sizes of crabs at repelling multiple coral predators.

In one trial, the research team removed T. flavopunctata from corals in the path of the sea stars. The results were dramatic; corals without T. flavopunctata crabs were eaten—usually overnight.  (To eat, a sea star must invert its stomach and drape it over a coral head. It then secretes digestive enzymes that dissolve the coral tissue and allow its stomach to absorb them.)

Small and large crabs belonging to “Trapezia serenei”(above) proved to be effective coral defenders against a range of predators; the smaller crabs protected the coral from Drupella snails while the larger crabs honed in on mid-sized sea stars. (Photo copyright David Liittschwager)

“Seemingly small differences among crabs guarding their coral homes can have big effects on coral survival,” Moore says. “Not only does the level of protection provided vary by species, but the smallest crabs were defending the coral from coral-eating snails, a threat that larger crabs ignored.”

Multiple species of crabs live inside a coral in monogamous male-female pairs. Only one pair of the same species resides in each coral and they will fight off others of their same species that intrude on their territory. “They don’t like to live in the same coral host with the same species unless they are a mated pair,” Moore says.

Moore and McKeon concluded that multiple lines of defense are a direct result of guard-crab diversity and are necessary to keep coral reefs safe long-term.

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Eastern Meadowlark (Photo by Gerrit Vyn)

The report card is in for the state of the birds in the USA. So how did we do? Certainly not an A+ or even a B, but that means there is room for improvement! What did the scientists find and how can we help? Read on.

Hawaii is the bird extinction capital of the world.

Hawaii is a paradise…of bird extinction. No place on Earth has had more bird extinctions since human settlement than the American tropical island state. Ten species of bird have gone extinct in the last 40 years and now the State of the Birds report has placed all of the native birds left, just 31 species, on the North American Bird Conservation Initiative watch list.

The lower Kalalau Valley, Koke’e State Park, Kauai, Hawaii (Photo: Alex Schwab)

So why did these birds disappear? Introduced predators like mongoose, cats and rats have played a big part. The mongoose was introduced to Hawaii in the mid-19th century in an attempt to control the large rat population in the sugarcane fields. However, since then the mongoose population has grown to large numbers without controlling the rat population. Instead these stealthy hunters decided to target much easier prey, ground nesting birds. But all is not lost as the people of Hawaii are fighting back, using predator proof-fences to keep these non-native predators away from the birds.

Feral mongoose on the island of O’ahu, Hawaii. (Photo by J.N. Stuart)

Keep Mr. Whiskers inside and save 2.4 billion birds!

We all love our little fur-babies but no matter how well-fed he is, it can be hard for Mr. Whiskers to suppress his wild side. You can help your feline friend stay on a no-bird diet by simply keeping him indoors. With an estimated 2.4 billion birds killed by cats in the U.S. each year, taking away the temptation to stray from his cat kibble diet is the biggest impact you can make on saving our native birds.

Grumpy Cat (Photo by imgflip.com)

You can storm proof your home by saving bird habitat!

You never know when another Superstorm Sandy is around the corner, but if you have a bird sanctuary nearby you might breathe a little easier. Coastal wetlands offer the best resilience to rising waters, something that coastal birds such as the endangered piping plover desperately need. Require more convincing? Talk to the residents of New Jersey! They were certainly grateful to coastal preserves for holding back the sea surge and floodwaters that threatened their homes in 2012.

Piping plover chicks (Photo: Kaiti Titherington, USFWS)

Hedwig’s family is getting smaller.

Many northern birds commonly visit the lower 48 states each year to migrate through or spend the winter. The most famous of these, the snowy owl, a species made legendary by the Harry Potter series, shift south across our borders only every few years. Scientists believe shrinking populations of snowy owl and other northern species may reflect changing climatic conditions in the Arctic. Many species are in steep decline and international efforts are underway to foster cross-border research and conservation to stop the widespread decline of our northern birds.

Put it in the trash can! Our floating garbage is killing our seabirds.

Giant patches of garbage floating out in the Pacific Ocean are not only an eyesore but also a deathtrap for many of our seabirds. In one study, more than 90 percent of northern fulmars found dead on beaches had plastic in their stomachs. When scientists looked inside the birds, they found consumer grade plastics like toothbrushes and bottle caps instead of the fish, squid and plankton they usually feed on. Don’t let your garbage become a chocking hazard for birds, put it in the trash can!

This albatross died filled with plastic items it had swallowed. (Photo by Chris Jordan)

#SOTB14

By Micaela Jemison 

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One hundred years after the extinction of the passenger pigeon, the nation’s top bird science and conservation groups have come together to publish The State of the Birds 2014—the most comprehensive review of long-term trend data for U.S. birds ever conducted. The authors call the results unsettling. The report finds bird populations declining across several key habitats, and it includes a “watch list” of bird species in need of immediate conservation help. The report also reveals, however, that in areas where a strong conservation investment has been made, bird populations are recovering. The full report can be found at stateofthebirds.org.

The State of the Birds 2014 is authored by the U.S. Committee of the North American Bird Conservation Initiative—a 23-member partnership of government agencies and organizations dedicated to advancing bird conservation. The report is based on extensive reviews of population data from long-term monitoring. It looks to birds as indicators of ecosystem health by examining population trends of species dependent on one of seven habitats: grasslands, forests, wetlands, ocean, aridlands, islands and coasts. This year’s report is also a five-year check-in on the indicators presented in the inaugural 2009 The State of the Birds report.

Bobolink, Chester County, Pa. (Photo by Kelly Colgan Azar)

After examining the population trends of birds in desert, sagebrush and chaparral habitats of the West, the report’s authors identify aridlands as the habitat with the steepest population declines in the nation. There has been a 46 percent loss of these birds since 1968 in states such as Utah, Arizona and New Mexico. Habitat loss and fragmentation due to development are the largest threats. These are also significant threats in the nation’s grasslands, where the report notes a decline in breeding birds, like the eastern meadowlark and the bobolink, of nearly 40 percent since 1968. That decline, however, has leveled off since 1990—a result of the significant investments in grassland bird conservation.

“This report highlights the threats that birds face, but it also offers hope for their future if we act together,” said Wayne Clough, Secretary of the Smithsonian Institution. “I am gratified that the Smithsonian contributed to this important effort, which shows that collaboration among agencies and organizations can yield valuable insights into difficult challenges.”

Feral mongoose on the island of O’ahu, Hawaii. (Photo by J.N. Stuart)

While habitat loss and fragmentation are the most consistent and widespread threats across habitats, they are closely followed on the list by invasive species. Introduced species have a particularly strong impact on islands where native birds have a greater restriction in where they can live. In Hawaii, introduced animals such as mongoose, rats and domestic cats serve as unnatural predators and take a huge toll on native species, while grazing livestock degrade habitat. One-third of all U.S. federally endangered birds are Hawaiian species.

However, as with many grassland birds, species in several other key habitats have benefited from targeted conservation. In general, shorebirds along the coasts are squeezed into shrinking strips of habitat due to development. But among the 49 coastal species examined, there has been a steady rise in population of 28 percent since 1968—a direct result of the establishment of 160 national coastal wildlife refuges and nearly 600,000 acres of national seashore in 10 states.

Female oak titmouse (Photo by David A. Hofman)

The creation and preservation of large swaths of forests through public-private partnerships in the Appalachian Mountains and the Northwest has helped declining forest-dependent species such as the golden-winged warbler and the oak titmouse. Efforts like this are essential, as forest-dependent birds have declined nearly 20 percent in the western U.S. since 1968 and 32 percent in the east.

Wetlands are one of the habitats to benefit most from conservation. The North American Wetlands Conservation Act has enabled strategic conservation projects covering a collective area larger than Tennessee. While wetland loss continues in some regions, the Act has helped protect and restore wetlands through public-private partnerships across the United States, thereby reversing declines in waterfowl populations such as the mallard and blue-winged teal.

Blue-winged teals (Photo by Dan Mullen)

In addition to assessing population trends in the seven key habitats, the North American Bird Conservation Initiative members created a The State of the Birds Watch List. The 230 species on the list are currently endangered or at risk of becoming endangered without significant conservation. Forty-two of them are pelagic (open ocean) species. Birds like the Laysan’s albatross and black-footed albatross are facing increasing levels of oil contamination, plastic pollution and greatly reduced amounts of prey fish due to commercial fishing operations. Rising sea levels due to climate change also put their low-elevation breeding habitats in the Hawaiian and Marshall islands at risk of flooding.

More than half of all U.S. shorebird species are on the Watch List, including the piping plover, long-billed curlew and red knot. Loss of habitat and uncontrolled harvesting in the South America and Caribbean are some of their biggest threats.

A red knot brooding freshly hatched chicks on her nest in Chukotka, Russia. (Photo by Gerrit Vyn)

One of the more dire groups on the Watch List is made up of the 33 Hawaiian forest species, 23 of which are listed as federally endangered. The report’s authors have deemed Hawaii the “bird extinction capital of the world”—no place has had more extinctions since human settlement. They point to proactive, partner-driven conservation as the best way to recover endangered birds and keep other species off the Endangered Species List, not only in Hawaii but in all key habitats.

Another group on the Watch List will require international cooperation: neotropical migrants. These species that breed in North America but migrate south of the U.S. border in winter hold 30 spots on the Watch List. Species like the Bicknell’s thrush, a bird that breeds in the mountains in the Northeast, faces rapid deforestation of its already limited wintering grounds on the island of Hispaniola. A positive precedent, however, lies with the cerulean warbler, a species that breeds in forests of the eastern U.S. and winters in the tropics. While its numbers are still declining, it has benefited by international collaborations to not only create healthy breeding habitat in the U.S., but good wintering habitat in Colombian coffee-growing landscapes.

Grasshopper sparrow (Photo by Dave Govoni)

The passenger pigeon, once numbering in the billions, is a strong reminder that even species considered common can become extinct without careful attention, as it did Sept. 1, 1914. Another focus for The State of the Birds 2014 is the importance of keeping common birds common. The report identifies 33 species, like the northern bobwhite quail, grasshopper sparrow and bank swallow, that do not meet the Watch List criteria but are declining rapidly in many areas. These birds have lost more than half their global population, and the 33 species combined have lost hundreds of millions of breeding individuals in just the past 40 years.

The report points, once again, to conservation as the most valuable solution to stopping these species from joining the Watch List. Addressing the conservation needs of these birds will result in healthier, more productive land and water for other wildlife, as well as for people.

The strongest finding in The State of the Birds 2014 is simple: conservation works. Ducks fly once again in great numbers up the Mississippi River and across the Chesapeake Bay. California condors are rebounding from just 22 birds to more than 200 today. Bald eagles, brown pelicans, peregrine falcons—all species once headed the way of the passenger pigeon—are now abundant. To prevent future extinctions like the passenger pigeon, the report’s authors point to science, technology and knowledge as the foundation of proactive partner-driven conservation.

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Wetlands

Wetlands are one of the habitats to benefit most from conservation. The North American Wetlands Conservation Act has enabled strategic conservation projects covering a collective area larger than Tennessee. While wetland loss continues in some regions, the Act has helped protect and restore wetlands through public-private partnerships across the United States, thereby reversing declines in waterfowl populations such as the mallard and blue-winged teal.

Arid and Grasslands

After examining the population trends of birds in desert, sagebrush and chaparral habitats of the West, the report’s authors identify aridlands as the habitat with the steepest population declines in the nation. There has been a 46 percent loss of these birds since 1968 in states such as Utah, Arizona and New Mexico. Habitat loss and fragmentation due to development are the largest threats. These are also significant threats in the nation’s grasslands, where the report notes a decline in breeding birds, like the eastern meadowlark and the bobolink, of nearly 40 percent since 1968. That decline, however, has leveled off since 1990—a result of the significant investments in grassland bird conservation.

Forests

The creation and preservation of large swaths of forests through public-private partnerships in the Appalachian Mountains and the Northwest has helped declining forest-dependent species such as the golden-winged warbler and the oak titmouse. Efforts like this are essential, as forest-dependent birds have declined nearly 20 percent in the western U.S. since 1968 and 32 percent in the east.

Coasts

More than half of all U.S. shorebird species are on the Watch List, including the piping plover, long-billed curlew and red knot. Loss of habitat and uncontrolled harvesting in the South America and Caribbean are some of their biggest threats. In general, shorebirds along the coasts are squeezed into shrinking strips of habitat due to development. But among the 49 coastal species examined, there has been a steady rise in population of 28 percent since 1968—a direct result of the establishment of 160 national coastal wildlife refuges and nearly 600,000 acres of national seashore in 10 states.

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The nation’s top bird science and conservation groups have come together to publish The State of the Birds 2014—the most comprehensive review of long-term trend data for U.S. birds ever conducted.

The report finds bird populations declining across several key habitats, and it includes a “watch list” of bird species in need of immediate conservation help.

The report also reveals, however, that in areas where a strong conservation investment has been made, bird populations are recovering. The full report can be found at stateofthebirds.org.

#STOB14

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Q: Are things getting better or worse for birds in the United States?

The 2014 The State of the Birds report provides both encouraging and discouraging findings. The report finds bird populations declining across several key habitats and includes a “watch list” of bird species in need of immediate conservation help. The report also reveals, however, that in areas where a strong conservation investment has been made—wetland birds, for example—bird populations are recovering and growing.

Q: What birds are worse off, better off?

Birds in aridland habitat show the steepest population declines in the nation. There has been a 46 percent loss in the population of these birds since 1968. Habitat loss, hydrological alteration, overgrazing and conversion to agriculture are the largest threats. These are also significant threats in the nation’s grasslands, where the report notes a decline in breeding birds, like the eastern meadowlark and the bobolink, of nearly 40 percent since 1968. That decline, however, appears to have leveled off since 1990—a result, the authors say, of the significant investments made in grassland bird conservation

Lesser prarie chicken, a threatened bird of the arid grasslands. (Photo by J.N. Stuart)

In addition, introduced species have had a particularly strong impact on native island birds. In Hawaii, introduced animals such as mongoose, rats, domestic cats, pigs and goats have taken a huge toll on native species. One third of all of America’s federally endangered birds are Hawaiian species.

There are some encouraging signs for many species in grasslands, wetlands and several other key habitats that have benefited from targeted conservation efforts. In general, development is squeezing shorebirds and their habitat along the coasts. However, among the 49 coastal species examined, there has been a steady rise in populations of 28 percent since 1968. This may be a reflection of the establishment of 160 national coastal wildlife refuges and nearly 600,000 acres of national seashore in ten states.

The creation and preservation of large swaths of forests through public-private partnerships in the Appalachian Mountains and the Northwest is believed to have helped declining forest-dependent species such as the golden-winged warbler and the oak titmouse. Efforts like this are essential, as forest-dependent birds have declined nearly 20 percent in the western U.S. and 32 percent in the east since 1968.

Q: What are some bird species that warrant conservation attention given the findings of the 2014 report?

Declining species include:

Palila—one of many unique Hawaiian forest birds that continue to decline and are perilously close to extinction. These birds require immediate strong conservation actions to protect and restore native forest habitats by fencing and eradicating non-native ungulates such as non-native mouflon sheep and controlling introduced predators such as feral cats and mongoose.

Bendire’s thrasher—declining at 4.6 percent each year over 45 years; threatened by loss of desert scrub habitat due to urban expansion and conversion to agriculture, exacerbated by prolonged drought and increased temperatures related to climate change.

Hudsonian godwit (Photo courtesy U.S. Fish and Wildlife Service)

Hudsonian godwit—among the steepest declining (-6.2 percent per year since 1974) of a large suite of declining, long-distance migrant shorebirds; threatened primarily by disturbance and loss of highly localized wintering sites along the South American coasts, due to aquaculture (e.g. shrimp farming) and coastal development, as well as disturbance and loss of spring stopover habitat in the Gulf-coastal and mid-western prairies.

Chestnut-collared longspur—declining by more than 4 percent per year over 45 years; threatened by continued loss of native prairie grassland due to conversion to agriculture (crops), and especially in recent years by rapid loss of native grassland in the Chihuahuan Desert grassland region of northern Mexico due to unchecked and often illegal conversion to pivot-irrigation agriculture.

Cerulean warbler in Carrol County, Md. (Photo by Frode Jacobsen)

Cerulean warbler—declining by 3 percent each year over 45 years; threatened by unsuitable structure and composition of mature deciduous forest, especially in the Appalachians; improper forest management; urban expansion; and loss of montane forests in the Andes due to rapid clearing for pasture and agriculture.

Q: What are some of the notable success stories?

American Oystercatcher—U.S. coastal populations have increased 6 percent per year since 1974. Recent population increases and range expansion can be attributed to targeted conservation actions to protect breeding and roosting sites along the Atlantic Coast, supported by the National Fish and Wildlife Foundation and other partners.

American oystercatcher (Photo by Kelly Colgan Azar)

Wood ducks, gadwall, and ring-necked ducks are among the harvested waterfowl that have increased 2-3 percent per year over the past 45 years, as a direct result of wetland habitat management and restoration under the North American Waterfowl Management Plan.

Kirtland’s warbler—an endangered species that has responded positively to targeted conservation efforts under the Endangered Species Act; its population rebounded from a low of 167 males counted in 1974 to more than 2,000 in 2012, and the range is slowly expanding from its tiny core in Michigan to adjacent areas in Wisconsin and Ontario.

Bald eagle—recovering at a remarkable rate of 5.5 percent each year since the banning of pesticides such as DDT and the enactment of the Clean Water Act in 1972; they were removed from the U.S. Endangered Species List in 2007. Other fish-eating birds such as osprey, brown pelican, double-crested cormorant, and northern gannet have enjoyed large population increases as well.

Florida wild turkey (Photo by Heather Paul)

Wild turkey—increasing at one of the fastest rates of any North American bird (8 percent per year since 1966), in direct response to habitat management and reintroduction programs by state wildlife agencies and private hunting groups. The comeback of the wild turkey is considered one of the greatest conservation success stories in U.S. history.

Q: Are there any new or emerging threats to birds?

Climate change is becoming increasingly important as a looming threat to birds. Sea-level rise affects breeding habitat for coastal birds, island birds, and colonial seabirds. Warming temperatures in Hawaiian forests are allowing mosquitoes to move up into higher elevations, reducing the amount of habitat free of avian malaria. Warming ocean temperatures are also disrupting stocks of prey fish that seabirds rely on. An immediate threat is the drought in the West. This puts additional pressure on aridland birds that are already being affected by hydrological alteration, overgrazing, and conversion to agriculture. More is being learned about anthropogenic mortality thanks to recent studies which identify cats and collisions with buildings and automobiles as the leading human-caused sources of bird mortality.

This albatross died filled with plastic items it had swallowed. (Photo by Chris Jordan)

Q: How can federal and state governments better protect birds?

There are more than a dozen key governmental programs that deliver bird conservation results and some of their successes are reflected in this year’s The State of the Birds report. Those programs require continued local and federal government support and funding and include: the Land and Water Conservation Fund, the Neotropical Migratory Bird Conservation Act, Migratory Bird Joint Ventures, the Farm Bill (which contains several key conservation features), and the North American Wetlands Conservation Act.

Q: Why should people be concerned with the overall state of birds?

Birds are vitally important indicators of ecosystem health. By examining population trends of species dependent on the seven habitats—grasslands, forests, wetlands, ocean, arid lands, islands and coasts—it can be better assessed how well or poorly those systems are operating and possible sources of problems and corrective actions can be better identified.

Q: What is the State of the Birds Report and who creates it?

The State of the Birds Report provides an extensive review of population data from long-term monitoring. This year’s report is also a 5-year check-in on population indicators presented in the inaugural 2009 State of the Birds report. The State of the Birds 2014 report is authored by the U.S. Committee of the North American Bird Conservation Initiative, a 23-member partnership of government agencies and organizations dedicated to advancing bird conservation.

Q: How can individual citizens help protect birds?

There are many actions that individuals can take to help birds in their area. For example: buy Duck Stamps which help fund conservation work; buy Smithsonian Certified Organic Bird Friendly coffee; drink organic half and half in your coffee, as some data are showing very encouraging bird conservation findings associated with organic dairy farms; use fewer pesticides; create more natural habitat in yards; keep cats indoors and don’t let dogs run free; and keep feeders and water sources fresh.

For more tips, check out these links:
abcbirds.org/newsandreports/releases/140624.html
abcbirds.org/newsandreports/releases/140320.html

Those interested in more in-depth bird conservation activities might want to consider a host of citizen science opportunities, including:

• The North American Breeding Bird Survey
• The Christmas Bird Count – longest-running citizen science survey in the world
• Project Puffin partnership
• The citizen science program at Cornell Lab of Ornithology
• USA-National Phenology Network: Nature’s Notebook

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A heterosexual pair of “Planes major” crabs hiding in the space beneath the shell and above the tail of a juvenile loggerhead sea turtle (“Caretta caretta”). The turtle’s tail has been pulled aside to show the crabs. (Photo courtesy of Ricardo Santos)

In theory, crabs of the species Planes major should stay true to their mates for life. Heterosexual pairs of these small crustaceans live on loggerhead sea turtles, tucked snugly in the tiny space between a turtle’s tail and its shell. By sharing this small refuge with a member of the opposite sex the problem of finding a mate is solved. Normally only one male and one female crab are found on a turtle, hitching a ride as the turtle navigates the ocean.

Marine turtles are not abundant in the immense sea, so they represent a scarce resource the crabs need to stay alive. Both male and female readily defend their turf on a host turtle, for to fall off in the open ocean means certain death. These small crabs are not strong swimmers and represent a nice snack for predatory fish.

Now, a new study suggests the male crabs are less prone than originally thought to stay with their mating partners for long periods, and readily switch mates when the opportunity arises. When exactly they switch and how is a real puzzle. The study is published in the Journal of Experimental Marine Biology and Ecology.

Just going for a stroll on a sea turtle’s shell is “risky behavior,” explains study co-author Antonio Baeza of the Department of Biological Sciences at Clemson University and the Smithsonian Marine Station at Fort Pierce, Fla.

“We don’t know how long it takes for a crab to find another turtle, and thus another mate,” explains Baeza, who researches the behavioral ecology and mating behavior in ocean organisms. “Somehow, somewhere, the males are switching between turtle hosts, most probably in search of new females.”

While jumping to another turtle may earn a male a new mate, a battle to the death with another male reluctant to give up his mate and home might first ensue.

Scientists reached their conclusion by describing the symbiotic association between crabs and turtles, including the comparison of the body size of paired crabs found on hundreds of turtles studied in Japan, Mexico, Peru and Brazil. Previous research has shown that animals that stay together in the same refuge and display monogamous behavior for long periods have bodies that are very similar in size. Body-size data collected from P. major crabs during the study did not support evidence of extended monogamy.

The scientists also found a relatively high percentage of females with eggs and also solitary males that were living alone on turtles. This evidence again suggests roaming behavior by males, although the same behavior by females cannot be ruled out, Baeza observes.

“At certain times during the year loggerhead turtles gather for feeding and to mate,” Baeza says. “It may be during these times the crabs find an opportunity to jump to another turtle.”

P. major crabs are also frequently found living on flotsam in the ocean, so they may jump off and onto a mass of floating debris, drifting in the ocean currents until once again, if ever, they are presented with an opportunity for a long, monogamous voyage with a new mate.

–John Barrat

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The practice of selectively fishing male blue crabs in the Chesapeake—intended to give females a chance to reproduce—may have a hidden cost. A Bay without enough males could reduce the number of offspring females produce, ecologists at the Smithsonian Environmental Research Center paper published in the July issue of Marine Ecology Progress Series.

Maryland and Virginia began reducing the harvest of female crabs by commercial and recreational watermen in 2008, the year officials declared the blue crab fishery a federal disaster. Since then, the crabs have shown signs of a shaky recovery. But a lasting comeback hinges on females producing enough offspring.

Male blue crabs can mate with multiple females. But with fewer men to go around, their female partners are left with less sperm to reproduce. (SERC image)

A female blue crab can mate for just one short period in her life, during a few days after she molts to maturity. This gives male blue crabs a very short window of time to inject her with the sperm that will fertilize the millions of eggs she will produce in the next year or two.

In a healthy population, this is not usually a problem. The odds are good that she will find a male partner with a fully stocked supply of sperm. But when male crabs decline, the males that remain mate more frequently, often before they have a chance to regenerate their sperm supply. The females are forced to make do with less.
“It would be like trying to bake eight loaves of bread and only having enough yeast for two or three,” said Matt Ogburn, a postdoctoral fellow at SERC and lead author of the study.

To find out if there is a link between fewer males and diminished sperm in females, Ogburn and a team of SERC ecologists purchased blue crabs from commercial watermen on the Rhode River. They looked exclusively at recently mated females collected between June and October of 2010. Then they compared the number of sperm in each female with each month’s operational sex ratio—the ratio of reproductively active male to female crabs in the river.The number of sperm females received was lowest in August, when the operational sex ratio hit a low point of 2.4 mature males for every nubile female. They jumped to their highest levels in the fall, when the ratio reached as high as 15 to 1.

Left: Two blue crabs mating. Right: A “sponge crab.” The sponge is a dense mass made up of millions of eggs. (SERC image)

Ogburn’s team then attempted to predict how a limited sperm supply would impact the number of broods a female crab could produce in her lifetime. In a perfect world, a female crab in the Chesapeake Bay might produce as many as eight broods of roughly 3 million eggs each in two years, totaling up to 24 million eggs. But no one is sure how many sperm per egg a female crab needs to reproduce successfully. If it’s a simple one-to-one ratio, even a drastic reduction in sperm wouldn’t do much damage, according to a model the team created. But if the necessary ratio is higher, say, 25 or more sperm cells per egg, a sperm shortage could have dire consequences. Female crabs in those scenarios might produce only one or two broods in their lives, or none.

Ogburn’s team estimated that the crabs need an average of eight sperm per egg. At this ratio, an average female in the Chesapeake likely has enough sperm to produce two to three broods, totaling 6 to 9 million eggs. Another mystery is how many females survive long enough to produce more than two to three broods of offspring. If it is a small percentage, the reductions in sperm Ogburn’s team observed may have only a minor effect on the population. On the other hand, “if female harvest restrictions are successful in protecting females long enough to reproduce in a second year, they may not have enough sperm left to continue reproducing,” Ogburn said.  “Until we know how many females are surviving to reproduce in a second year, it is hard to know how much of a problem these reductions in sperm are.”

–Kristen Minogue

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The name Panama is said to mean “abundance of fish.” Now a new study estimates that between 1950 and 2010, the amount of fish taken from Panama’s waters was so considerable that officials could not keep tabs on more than a third of the catch.

For the last three years Héctor Guzmán of the Smithsonian Tropical Research Institute and colleagues from the University of British Columbia have been compiling official data and dozens of studies of off-the-books fisheries in Panama. They cautiously estimated that almost 40 percent of the total catch — including tuna, lobster, shellfish and shark — was unaccounted for. Today, as fish stocks dwindle, this revelation may contribute to establishing sustainable fisheries in Panama and the region.

“We estimated missing and under-reported components very conservatively so this is likely still an underestimate of what is being removed,” said Sarah Harper, of UBC’s Sea Around Us Project who was the lead author on the study published in Marine Fisheries Review. Guzmán and UBC’s Kyrstn Zylich and Dirk Zeller co-authored the research.

A fishing boat in Panamanian waters.

The discrepancy is due to minimal reporting of bycatch by commercial vessels and a dearth of data from recreational, subsistence and artisanal fishers. Illegal fishing by foreign vessels and catches by Panamanian-flagged ships operating from foreign ports also play an important role.

“We were not surprised by these alarming results,” said Guzmán a marine ecologist known for research that underpins regional conservation policy. “This is the first fishery baseline made for Panama. We hope to promote an open and all-inclusive dialogue to implement management tools for sustainable fisheries.”

The researchers recommend an overall reorganization of the fishing sector to include better monitoring, planning and surveillance of fishing zones and better managed marine protected areas. Curtailing carte blanche commercial fishing licenses, which are sometimes species indiscriminate, would also help, said Guzmán.

From anchovies to Sharks

Panama’s industrial fisheries developed in the 1960s to harvest herring and anchovies for fishmeal and oil for export. The scallop fishery reached its apex in the 1980s and collapsed without recovery in 1991. Shrimp, tuna, lobster and conch harvesting continue, with many populations now in decline.

Relatively new targets are sharks, especially hammerheads, for sale of shark fins overseas. Sharks are often harvested in inshore areas, including vulnerable nurseries. “There is likely substantial under-reporting of catches by domestic vessels and possibly a large number of sharks being caught by foreign vessels operating illegally in Panamanian waters,” the authors wrote.

Under-reporting of catch is not unique to Panama and improved monitoring does not have to be prohibitively costly. “Resource-limited countries can still effectively monitor their fisheries by implementing regular, non-annual surveys,” said the authors. “For Panama to retain meaning in its name (“abundance of fish”), fisheries management will need to make substantial improvements.”

–By Beth King, STRI

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