Climate Change, Conservation, Nature

Old Nautical Charts Reveal Coral Loss

British navigation charts from the 1800s show us how much coral has disappeared.
British navigation charts from the 1800s show us how much coral has disappeared. Photo: Shutterstock

Nautical charts mapped in the 18th century are showing modern researchers just how much coral has been lost around the world.

A new U.S. and Australian study has compared early British navigation charts to modern coral habitat maps to determine what changes have taken place over the past three centuries.

The study was led by Professor Loren McClenachan of Colby College in Waterville, Maine, with assistance from the University of Queensland (UQ) in Australia and the Australian Research Council Centre of Excellence in Coral Reef Studies.

Professor John Pandolfi of UQ said that the study used information from “surprisingly accurate” 18th century nautical charts and satellite data to understand coral loss in the Florida Keys.

Professor McClenachan said that more than half of the coral reef habitat mapped in the 1770s was no longer there. In some areas, coral loss was close to 90 percent.

“We found near the shore, entire sections of reef are gone, but in contrast, most coral mapped further from land is still coral reef habitat today,” McClenachan said.

This is one of the first studies where marine scientists have measured the loss of coral reef habitats over a large geographic area. Most studies look more closely at the loss of living coral from smaller sections of reefs.

“We found that reef used to exist in areas that today are not even classified as reef habitat anymore,” Pandolfi said. “When you add to this the 75 percent loss of living coral in the Keys at that finer scale, the magnitude of change is much greater than anyone thought.”

Dr. Benjamin Neal of the Bigelow Laboratory for Ocean Sciences in East Boothbay, Maine, said that the early maps were remarkably precise.

“They had the best technology and they used it to create new information that conferred a lot of power,” Neal said. “The maps were essential to expansion of the British Empire, and luckily for us, they also included a lot of useful ecological information.”

This research has important conservation implications. As the authors said, when large-scale changes like this were overlooked, scientists could miss out on information about past abundance.

“We tend to focus on known areas where we can measure change. That makes sense. Why would you look for coral where you never knew it was?” McClenachan said.

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Climate Change, Environmental Hazards, Nature, Science

Was Hurricane Harvey Caused by Global Warming? Not Entirely

Was Hurricane Harvey caused by global warming? Not entirely.
Cars submerged by flooding in the wake of Hurricane Harvey. Photo: michelmond / Shutterstock.com

Climate change is responsible for a lot of things, but it may not be directly responsible for Hurricane Harvey.

Harvey is not the first hurricane to hit the Texas coast.  A deadly hurricane struck Galveston in 1900, and that storm caused thousands to lose their lives, primarily due to the lack of warning. Meteorology was not an advanced science at that time, and there were no satellites to track the storms as they moved across the Atlantic Ocean.

However, climate change is almost certainly responsible for the epic rainfall and catastrophic flooding endured by the cities struck by Hurricane Harvey.

“This is they type of event, in terms of extreme rainfall, that we would expect to see more of in a warming climate,” Dr. Friederike Otto from the University of Oxford told the BBC.

In fact, the rainfall was so extreme that the National Weather Service had to add new colors to its rainfall maps to account for the intensity of Harvey’s rains.

There’s a physical law called the Clausius-Claperyon equation, which says that a hotter atmosphere holds more moisture. For every degree Celsius in warming, the atmosphere can hold 7 percent more water, which makes rainfall events more extreme.

The temperature of the seas also contributes to the strength of hurricanes.

“The waters of the Gulf of Mexico are about 1.5 degrees warmer than they were from 1980 to 2010,” Sir Brian Hoskins of the Grantham Institute for Climate Change told the BBC. “This is very significant because it means the potential for a stronger storm is there, and the contribution of global warming to the warmer waters in the Gulf, it’s almost inevitable that there was a contribution to that.”

Although there have been slow-moving storms over Texas in the past, some scientists still attribute the intensity of Harvey to climate change.

Professor Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research says that a general slowdown in atmospheric circulation in the earth’s middle latitudes could be a result of changing climate in other parts of the world.

“This is a consequence of the disproportionately strong warming in the Arctic,” Rahmstorf said. “It can make weather systems move less and stay longer in a given location—which can significantly enhance the impacts of rainfall extremes.”

Other scientists think it’s a stretch to believe that the slowly moving nature of the storm is caused by climate change. “I don’t think we should speculate on these more difficult and complex links like melting in the Arctic without looking into these effects in a dedicated study,” said Dr. Otto.

In addition to the damage caused by the flooding, pollution is causing the floodwaters to become a toxic stew of sewage, garbage, chemicals from more than 20 Superfund sites in the Houston area, oil and petrochemicals from damaged refineries, and much more, are causing concern.

“There’s no need to test [the water],” Houston Health Department spokesman Porfirio Villareal told the New York Times. “It’s contaminated. There’s millions of contaminants.”

Climate Change, Nature, Science

Galápagos Seabird Population May Shrink Due to Global Warming

Nazca boobies and other animals are in jeopardy as water warms around the Galápagos Islands.
A Nazca booby guards her egg. Photo via Pixabay

The Galápagos Islands are the home of thousands of unique species. In fact, those islands were where Charles Darwin began writing about his findings on evolution. But at least one of these species is in jeopardy because of warming ocean temperatures.

Within the next century, rising ocean temperatures around the Galápagos Islands are expected to make the water too warm for sardines to tolerate.

Why is that important? Sardines are a key prey species for many seabirds including the Nazca booby.

Wake Forest University biologists published a study in the August 23 issue of the journal PLOS ONE about this phenomenon. They used decades of data on the diet and breeding of the Nazca booby to understand how the absence of sardines could affect the booby population.

They studied the diet, breeding, and survival of Nazca boobies as part of their study at Isla Españnola in the Galápagos Islands for more than 30 years. In 1997, halfway through their study, sardines disappeared from Nazca booby diet samples, replaced by flying fish.

Flying fish are less nutritious than sardines, and as researcher Emily Tompkins, lead author of the study, said, as flying fish replaced sardines in the birds’ diet, “reproductive success was halved.”

“If the current links between diet and reproduction persist in the future, and rising ocean temperatures exclude sardines from the Galápagos, we forecast the Nazca booby population will decline,” Tompkins said.

David Anderson, a professor of biology and co-author of the study, said, “Few connections have been made between ocean warming and population effects in the tropics, making this study significant.”

But the Nazca booby isn’t the only creature that could be harmed by rising ocean temperatures. The study suggests that other Galápagos predators that do well when sardines are available will have to adjust to a new menu within the next 100 years.

So many species have gone extinct or become highly endangered due to global climate change—probably including species we never even discovered—that it behooves us to act to stop, or at least slow, climate change. Given the United States’ exit from the Paris Climate Agreement, it’s up to other nations, and states and cities within the U.S., to step up and do something about this increasing danger to the survival of all animals, including humans.

Nature, Science

Surprise! Two Different Species of Butterflies Are Actually Not Two Different Species

Researchers have recently discovered that what they thought was a unique species of butterfly was actually the female of a species that has been known for more than a century.
Researchers are constantly learning about new species of tropical butterflies. Who knows what they’ll find out about this white baumnymphe butterfly in the future? Photo via Pixabay

The iridescent blue male sunburst cerulean-satyr butterfly has been known for more than a century. But a more recently discovered dull brown butterfly was given a completely different species name.

However, an international team of nine butterfly researchers used DNA “bar code” sequence data to prove that the dull brown butterfly is actually the female cerulean-satyr butterfly.

Males and females look dramatically different from one another, a phenomenon called sexual dimorphism. This is common in birds, where, for example, the male Anna’s Hummingbird is very bright and flashy, whereas the female’s feathers boast a much more muted color palette.

The classification mistake with the butterflies probably occurred because the brown butterflies are rare than the blue ones, and because sexual dimorphism is not common in most species of butterflies.

The research team collected and analyzed DNA bar codes—short, diagnostic gene sequences—for more than 300 species across the euptychiine group of butterflies that includes the sunburst cerulean-satyr. It turned out that the DNA sequences for the sunburst cerulean-satyr and the dull brown butterfly, which had been given a completely different species name, were identical.

“None of us thought about this possibility before, and we were all surprised by this outcome of our DNA analysis,” said study lead author Shinichi Nakahara of the University of Florida. “Given that males and females of most euptchiine butterflies look more or less the same, I guess no one thought that the female would look so different compared to the male.”

The discovery of the female sunburst cerulean-satyr butterfly contributed to the recognition of the male and female of two other species in this group, including a new species from the cloud forests in eastern Ecuador. The different-looking males and females of the two species means that the euptchiine group of butterflies is one of the most sexually dimorphic among the species.

A better understanding of the diversity and relationships among euptchiines makes it possible for scientists to think about bigger questions like why and how they diversified and the role wing patterns play in signaling between the sexes, Nakahara said.

“Our study will serve as the basis for developing a firm understanding of the true species diversity of this group and of Neotropical butterflies in general,” Nakahara said. “These findings are extremely valuable at a time when the biodiversity of the Neotropics is threatened, since it will be impossible to recognize and document the region’s unique elements of biodiversity after they are gone.”

Nature, Science

U.S. to Be Treated to a Full Solar Eclipse in August

Americans are going to be treated to a full solar eclipse on August 21, 2017.
Americans are going to be treated to an amazing event on August 21. Photo via Pixabay

On August 21, the moon will come between the earth and the sun, casting a 70-mile shadow from Oregon to South Carolina in what is likely to be the most-viewed solar eclipse ever recorded.

Already being referred to as the “Great American Eclipse,” this will be the first coast-to-coast solar eclipse in 99 years.

“The US only covers 2 percent of the globe, so we get very few eclipses,” said Matthew Penn, an astronomer at the National Optical Astronomy Observatory. “And to have one travel across the entire country is an unprecedented sort of opportunity. It’ll be a heck of a day.”

Penn will be running a project during the eclipse called Citizen CATE (Continental-America Telescopic Eclipse) that will attempt to record and put together a movie of the full eclipse in order to study the sun’s magnetic field. Data will be collected via telescopes, cameras, and computers operated by volunteers across the country.

The eclipse will first be visible from the Oregon coast around 9:05 AM on the 21st, after which a partial eclipse will be viewable across the entire US, including Alaska and Hawaii. Canada, Central America, and northern South America will also get a view at varying points throughout the day.

More than 200 million people currently live within a day’s drive of the eclipse, which means it’s likely to be seen by more people than any other eclipse in recent history.

Scientists are particularly excited about the part of the eclipse during which the sun’s corona, a magnetically energized region just above the sun’s surface, will be visible. Temperatures in this region will climb from 10,000 degrees Fahrenheit to nearly 4 million degrees—and scientists still don’t know why. So the chance to study the area more closely is pretty exciting, particularly since the innermost regions can only be seen during a total solar eclipse.

In addition to various individual Earth residents, 11 NASA spacecraft and more than 50 high-altitude balloons will be taking photos and studying the effects of the eclipse on the earth’s atmosphere.

If you want to see the eclipse, be sure to wear proper viewing glasses to avoid damaging your eyes. You’ll want shades with these specifications, provided by NASA:

  • Certification information with a designated ISO 12312-2 international standard
  • Manufacturer’s name and address easily accessible to assure legitimacy
  • Less than three years old and without scratches or wrinkled lenses
  • NO homemade filters (they’re not as safe as the properly manufactured kind)

Happy solar eclipse viewing!

Conservation, Nature, Science

Home On the Range? Not So Much for Large Carnivores

New research reveals that large carnivores have lost more than 90 percent of their historic range.
Large carnivores like the cheetah have lost more than 90 percent of their historic ranges. Photo: Shutterstock

A recent study from the Oregon State University revealed that the six largest carnivores in the world have lost more than 90 percent of their historic range.

The researchers mapped the current range of 25 large carnivores and compared them with historic maps from 500 years ago.

“Of the 25 large carnivores we studied, 60 percent (15 species) have lost more than half of their historic ranges,” said researcher Christopher Wolf.

“As many carnivores were historically sympatric [descended from one common ancestor] and are at high risk of future range contraction, conservation should be accomplished at the level of whole predator guilds [groups of species that exploit the same resources, or who exploit different resources in related ways] when possible,” the researchers wrote in their report.

What this means is that contracting the range of one species—either through physical barriers like fencing or the widespread use of land for herds of domestic cattle—can have dramatic effects on large carnivores’ ability to survive in their historic ranges.

“This means that scientifically sound reintroductions of large carnivores into areas where they have been lost is vital both to conserve the large carnivores,” Wolf said. “This is very dependent on increasing human tolerance of large carnivores—a key predictor of reintroduction success.”

The researchers also say that reintroduction programs would be most successful in rural areas with low human population density and limited agricultural and livestock-raising use.

“Also, more large protected areas are urgently needed for large carnivore conservation,” said co-researcher William Ripple.

The good news is that it is possible to help these animals by changing human attitudes about them.

“Many large carnivores are resilient, particularly when human attitudes and policy favor their conservation,” the researchers wrote. “This helps to explain the large carnivore recoveries observed in Europe and elsewhere (e.g., gray wolves in the continental United States).”

Additionally, the relationship between increasing agriculture use and range contractions can be limited when predator-friendly agriculture methods are used.

But human exploitation of former large carnivore ranges isn’t the only thing we need to be on the lookout for.

“In the face of newer threats like anthropogenic climate change, it is critical to continue to monitor large carnivore ranges to ensure the future of these species,” the researchers conclude.

Ultimately, the stability of large carnivore populations is highly dependent on human behavior. Whether that involves evolution of agriculture and ranching methods or limiting the effects of climate change, the ultimate success of reintroducing these species in their historic ranges is dependent entirely on us.

Nature, Science

The World’s Oceans Now Have A Health Record

The oceans now have a health record, thanks to a team of scientists at UC Santa Barbara

Thanks to a team of researchers at UC Santa Barbara, the world’s oceans now have a health record.

And that health record is revealing clues about what might be behind ocean improvements or declines.

Analyzing data from 220 countries, the team gathered five years’ worth of ocean “vital signs” in a variety of areas ranging from water quality to food provision to tourism potential in order to create an Ocean Health Index. Their conclusion: While ocean health appears to be stable, the oceans around many of the countries analyzed are changing for the worse.

“With five years of assessments about where oceans are healthy and not as healthy, we finally have enough information to get a clear signal of what might be causing changes,” said study lead author Ben Halpern, executive director of the National Center for Ecological Analysis and Synthesis at UC Santa Barbara.

Countries like Indonesia, Mexico, and Samoa, that are seeing improvements in their oceans are taking action to make things better, including improving management of wild-caught fisheries and creating marine protected areas.

On the other hand, the countries that saw a decline in ocean health where in consistent political turmoil. Many Arctic and sub-Arctic countries are seeing declines as well, due to the fact that coastlines are losing sea ice, which is a natural protection from storm damage and erosion.

“The Ocean Health Index created the first opportunity any of us has had to measure the health of our oceans in a comprehensive way and track changes with a single measure,” Halpern said.

According to the researchers, the index has scored the oceans’ overall health staying steady at a 71 out of 100. This shows that while the oceans aren’t dying, they aren’t thriving, either. The team will continue to collect data on ocean health every year.

“We believe the Ocean Health Index gives reason for hope by providing a detailed diagnosis of the state of ocean health and a framework that allows countries to identify and prioritize the most necessary resilience actions to improve ocean health,” said study co-author Johanna Polsenberg, senior director of governance and policy for Conservation International’s Center for Oceans. “This is where our work is most valuable. It helps to identify and highlight the necessary steps to ensure a healthy ocean into the future.”

I don’t know about you, but after seeing all the news about dying reefs, pollution, and overfishing, I’m surprised the oceans are as healthy as they are. Hopefully this new information will help governments and scientists to improve their health.