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How many trees are there in the world?

Posted date: 8:27 AM / comment : 0 , , , ,

According to a new study, the answer is somewhere around 3.04 trillion.
That's about 400 trees for every person.
12,000 years ago, before the advent of agriculture, Earth had twice as many trees as it does now. Currently, our planet is losing 10 million trees a year.
"We used ground-sourced information," says Crowther. "All of the information that went into our models was generated from people standing on the ground counting numbers of trees in a given area. And so we could relate this information to what the satellites are telling us."
Previous estimates of the Earth's tree population put the number at 400.25 billion. That’s nearly an order of magnitude less than the new tally. Scientists say the discrepancy has to do with how the two estimates were calculated.
“Satellite images can tell you a lot about the forest area and canopy cover,” Crowther said. “What we provide is a more detailed understanding of what is going on beneath the surface.”
The new study incorporates satellite imagery, but it also relies on 429,775 ground-based measurements of tree density made by an actual person who counted the number of trees in a given area.
"We all gathered in a room, it was a very exciting time," remembers Crowther. "We'd been working toward it for two years."

The result: A staggering three trillion trees.

Researchers represented the number of trees across the globe using bars that are taller for denser forests.


Crowther added that one of the most dominant themes of the study is how large an effect humans are having on the tree population on the planet.

“Human activity came out as the strongest control on tree density across all biomes,” he said. “It really highlights how big of an impact humans are having on the Earth on a global scale.”


Chimpanzees and monkeys have entered the Stone Age

Posted date: 3:11 PM / comment : 2 ,

“Some Chimpanzees Have Entered Stone Age.” Scientists On 3 Continents Make Surprising Discovery.

In the rainforests of west Africa, the woodlands of Brazil and the beaches of Thailand, archaeologists have stumbled upon some fascinating stone tools.
What sets them apart is not the workmanship or their antiquity: they belong to the same age as the Egyptian pyramids.
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Source

What is exceptional about this discovery is that the tools were held by non-human hands.

The tools are crude. A chimpanzee or monkey stone hammer is hardly a work of art to rival the beauty of an ancient human hand axe. But that’s not the point. These primates have developed a culture that makes routine use of a stone-based technology. That means they have entered the Stone Age.
The chimpanzees of west Africa had used these tools in a cruder way, to crack open nuts for example.
A few years ago, biologists believed only humans could make extensive use of tools. However, recent discovery falsifies this claim.
Our closest living relatives might be similar to us, more than we could have ever imagined. An article published in Oxford journals suggests monkeys and chimpanzees have a flair for reading each other’s facial expressions.
This certainly calls for a re-assessment of primates.
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Countries like New Zealand and the United Kingdom consider experiments on apes, illegal. Spain for example, allots them some human rights. In the U.S. too, there are reforms taking place in this area. A trial pending in New York courts wants chimpanzees to be granted full human rights.
If nothing else, we should certainly be compassionate and sympathetic to our primate cousins.


For Further Reading

Psychologists have no idea how to rehabilitate sex offenders.

Posted date: 12:31 PM / comment : 0 ,

Prison programs that have been in place for decades to rehabilitate convicted sex offenders may not work at all, according to a new study.
Sex offender treatment programs — in which offenders follow a syllabus aimed at “normalizing” their sexual impulses and fantasies — have not been shown to reduce the likelihood that sex offenders will change their behavior after they get out of jail, forensic psychiatrist David K. Ho  in the BMJ medical journal.
Source

“No evidence from academic or policy research has shown that the treatment program significantly reduces sexual reoffending,” David K. Ho, a forensic psychologist at South Essex Partnership University in England, writes in BMJ. “Victims and the public deserve to know this.”

--> “Sex offenders are sent to prison, undergo this treatment program, are deemed to have been somewhat rehabilitated and are released to the public,” Ho wrote. “However, they are as likely to offend as before receiving treatment.”

In 2012, a major review of sex offender treatment programs concluded that for a regime that has been imposed on so many prisoners, there had not been nearly enough research proving its worth. No one has done studies rigorous enough to prove that it’s useless either, though — and that lack of data is a real problem. “Not only could this result in the continued use of ineffective (and potentially harmful) interventions, but it also means that society is lured into a false sense of security in the belief that once the individual has been treated, their risk of reoffending is reduced,” the authors wrote. “Current available evidence does not support this belief.”

--> Sex offenders who receive outpatient treatment are less likely to repeat offend than those who don’t receive this treatment, but the efficacy of sex offenders’ treatment while in prison is questionable at best. “Treatment varies widely — most programs combine cognitive behavioral therapy with lessons about empathy and anger management — and, in most cases, never ends,” writes Rachel Aviv in the New Yorker.

References

2. NCBI

Postmortem Stability of Ebola Virus

Posted date: 9:14 PM / comment : 0 , , ,

Date:
February 12, 2015
Source:
NIH/National Institute of Allergy and Infectious Diseases
Summary:
To determine how long Ebola virus could remain infectious in a body after death, scientists sampled deceased Ebola-infected monkeys and discovered the virus remained viable for at least seven days. They also detected non-infectious viral RNA for up to 70 days post-mortem.

Abstract

The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus–infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated 7 days posteuthanasia; viral RNA was detectable for 10 weeks.
Joseph Prescott, Trenton Bushmaker, Robert Fischer, Kerri Miazgowicz, Seth Judson, and Vincent J. Munster
Author affiliations: National Institutes of Health, Hamilton, Montana, USA

 Research: 
The ongoing outbreak of Ebola virus (EBOV) infection in West Africa highlights several questions, including fundamental questions surrounding human-to-human transmission and stability of the virus. More than 20,000 cases of EBOV disease (EVD) have been reported, and >8,000 deaths have been documented (1). Human-to-human transmission is the principal feature in EBOV outbreaks; virus is transmitted from symptomatic persons or contaminated corpses or by contact with objects acting as fomites (2). Contact with corpses during mourning and funeral practices, which can include bathing the body and rinsing family members with the water, or during the removal and transportation of bodies by burial teams has resulted in numerous infections (3).
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Assessing the stability of corpse-associated virus and determining the most efficient sampling methods for diagnostics will clarify the safest practices for handling bodies and the best methods for determining whether a person has died of EVD and presents a risk for transmission. To facilitate diagnostic efforts, we studied nonhuman primates who died of EVD to examine stability of the virus within tissues and on body surfaces to determine the potential for transmission, and the presence of viral RNA associated with corpses.

The Study

We studied 5 cynomolgus macaques previously included in EBOV pathogenesis studies and euthanized because of signs of EVD and viremia. Two animals were infected with EBOV-Mayinga and 3 with a current outbreak isolate (Makona-WPGC07) (4).
Immediately after euthanasia, multiple samples were collected: oral, nasal, ocular, urogenital, rectal, skin, and blood (pooled in the body cavity) swab samples and tissue biopsy specimens: from the liver, spleen, lung, and muscle. Swabs were placed in 1 mL of culture medium and tissue samples were placed in 500 ÎĽL of RNAlater (QIAGEN, Valencia, CA, USA), or an empty vial for titration, before freezing at −80°C. Carcasses were placed in vented plastic containers in an environmental chamber at 27°C and 80% relative humidity throughout the study to mimic conditions in West Africa (5). At the indicated time points (<9 days for 2 animals and 10 weeks for 3 animals), swab and tissue samples were obtained and used for EBOV titration on Vero E6 cells to quantify virus or for quantitative reverse transcription PCR (qRT-PCR) (40 cycles) to measure viral RNA, as reported (6,7).
Viral RNA was detectible in all swab samples and tissue biopsy specimens at multiple time points (Figure 1). For swab samples (Figure 1, panel A), the highest amount of viral RNA was in oral, nasal, and blood samples; oral and blood swab specimens consistently showed positive results for all animals until week 4 for oral specimens and week 3 for blood, when 1 animal was negative for each specimen type. Furthermore, oral swab specimens had the highest amount of viral RNA after the first 2 weeks of sampling, although after the 4-week sampling time point, some samples from individual animals were negative.
In all samples, RNA was detectable sporadically for the entire 10-week period, except for blood, which had positive results for <9 weeks. Tissue samples were more consistently positive within the first few weeks after euthanasia (Figure 1, panel B). All samples from the liver and lung were positive for the first 3 weeks, and spleen samples were positive for the first 4 weeks, at which time lung and spleen samples were no longer tested because of decay and scarcity of tissue. Muscle sample results were sporadic: a sample from 1 animal was negative at the 1-day time point and at several times throughout sampling.
Figure 1. Presence and stability of Ebola virus RNA in deceased cynomolgus macaques. Swab (A) and tissue (B) specimen samples were obtained at the indicated time points, and viral RNA was isolated and used in a 1-step quantitative reverse transcription PCR with a primer/probe set specific for the nucleoprotein gene and standards consisting of known nucleoprotein gene copy numbers. Line plots show means of positive samples from 5 animals up to the 7 day time point and from 3 animals thereafter. Error bars indicate SD, and - indicates time points at which ≥1 animal had undetectable levels of viral RNA at that time point. Absence of a hyphen indicates that all animals had detectible levels of viral RNA.
Figure 2. Efficiency of Ebola virus isolation from deceased cynomolgus macaques. Swab (A) and tissue (B) specimen samples were obtained at the indicated time points, and virus isolation was attempted on Vero E6 cells. Cells were inoculated in triplicate with serial dilutions of inoculum from swab specimens placed in 1 mL of medium or tissues homogenized in 1 mL of medium. The 50% tissue culture infectious dose (TCID50) was calculated by using the Spearman-Karber method (8). Line plots show means of positive samples from 5 animals to the day 9 time point. Error bars indicate SD.

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Viable EBOV was variably isolated from swab from all sampling sites. Among blood samples, those from the body cavity had the highest virus titer (2 × 105 50% tissue culture infectious doses/mL) and longest-lasting isolatable virus (7 days posteuthanasia) (Figure 2, panel A). Consistent with the qRT-PCR results, for swab samples, oral and nasal sample titers were highest, followed by those for blood samples, and relatively high titers were observed <4 days posteuthanasia (Figure 2, panel B). Similar to the qRT-PCR experiments, virus titers were higher in tissue samples than in swab samples but were not as sustained; all tissue samples were positive at day 3 posteuthanasia but negative by day 4.

Conclusions

The efficiency of detecting EBOV from corpse samples has not been systematically studied; this information is needed for interpreting results for diagnostic samples for epidemiologic efforts during outbreaks. We showed that viral RNA is readily detectable from oral and blood swab specimens for <3 weeks postmortem from a monkey carcass that was viremic at the time of death, in environmental conditions similar to those during current outbreak (5).
The stability of the target RNA used for RT-PCR is more robust than that of viable virus because degradation of any part of the genome (or proteins and lipids) would compromise the ability of the virus to replicate. Thus, the ability to isolate replicating virus in cell culture from postmortem materials was much less sensitive than detection of viral RNA by qRT-PCR. The sensitivity for quantitating infectious virus is probably lowered because of limitations in isolation efficiency on cell culture and necessary dilutions of tissues for homogenization for titration. Nonetheless, we detected viable virus <7 days posteuthanasia in swab specimens and 3 days in tissues, and showed that infectious virus is present at least until these times. Because virus titers decreased relatively sharply, despite sensitivity issues, it is unlikely that viable virus persists for times longer than we measured.
Humans who die of EVD typically have high levels of viremia, suggesting that most fresh corpses contain high levels of infectious virus, similar to the macaques in this study (9). Furthermore, family members exposed to EVD patients during late stages of disease or who had contact with deceased patients have a high risk for infection (2). The presence of viable EBOV and viral RNA in body fluids of EVD patients has been studied, and oral swabbing has been shown to be effective for diagnosis of EVD by RT-PCR compared with testing of serum samples from the same persons (10,11). However, detection limits for diagnostic swab samples are unknown for early phases of EVD, and blood sampling is probably more sensitive and reliable for antemortem diagnostics and should be used whenever possible, which has also been shown with closely related Marburg virus (12).
Although these studies included data from outbreak situations, they are limited in their sampling numbers, swabbing surfaces, and time course, and it is unknown how predictive they are for samples collected postmortem. It is essential to stress that swab samples should be obtained by vigorous sampling to acquire sufficient biologic material for testing, and development of a quality-control PCR target (housekeeping gene target) would be beneficial for sample integrity assessment, which is a limitation of this study.
In summary, we present postmortem serial sampling data for EBOV-infected animals in a controlled environment. Our results show that the EBOV RT-PCR RNA target is highly stable, swabbing upper respiratory mucosa is efficient for obtaining samples for diagnostics, and tissue biopsies are no more effective than simple swabbing for virus detection. These results will directly aid interpretation of epidemiologic data collected for human corpses by determining whether a person had EVD at the time of death and whether contact tracing should be initiated. Furthermore, viable virus can persist for >7 days on surfaces of bodies, confirming that transmission from deceased persons is possible for an extended period after death. These data are also applicable for interpreting samples collected from remains of wildlife infected with EBOV, especially nonhuman primates, and to assess risks for handling these carcasses.
Dr. Prescott is a research fellow in the Virus Ecology Unit at Rocky Mountain Laboratories, Hamilton, Montana. He is currently involved in the Ebola virus outbreak at the combined Centers for Disease Control and Prevention/National Institutes of Health diagnostic laboratory, Monrovia, Liberia. His research interests include the immune response, transmission, and modeling of viral hemorrhagic fevers.

Acknowledgments


We thank Darryl Falzarano and Andrea Marzi for use of animal carcasses upon completion of their studies and Anita Mora for providing assistance with graphics.
This study was supported by the Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health.

References

  1. Centers for Disease Control and Prevention. Ebola hemorrhagic fever [cited 2015 Jan 3]. http://www.cdc.gov.ezproxy.nihlibrary.nih.gov/vhf/ebola/
  2. Dowell SF, Mukunu R, Ksiazek TG, Khan AS, Rollin PE, Peters CJ. Transmission of Ebola hemorrhagic fever: a study of risk factors in family members, Kikwit, Democratic Republic of the Congo, 1995. J Infect Dis. 1999;179(Suppl 1):S87–91 . DOIPubMed
  3. Khan AS, Tshioko FK, Heymann DL, Le Guenno B, Nabeth P, KerstiĂ«ns B, The reemergence of Ebola hemorrhagic fever, Democratic Republic of the Congo, 1995. J Infect Dis. 1999;179(Suppl 1):S76–86. DOIPubMed
  4. Hoenen T, Groseth A, Feldmann F, Marzi A, Ebihara H, Kobinger G, Complete genome sequences of three Ebola virus isolates from the 2014 outbreak in West Africa. Genome Announc. 2014;2:e01331–14.
  5. Ng S, Cowling B. Association between temperature, humidity and ebolavirus disease outbreaks in Africa, 1976 to 2014. Euro Surveill.2014;19:20892 .PubMed
  6. Marzi A, Ebihara H, Callison J, Groseth A, Williams KJ, Geisbert TW, Vesicular stomatitis virus–based Ebola vaccines with improved cross-protective efficacy. J Infect Dis. 2011;204(Suppl 3):S1066–74. DOIPubMed
  7. Ebihara H, Rockx B, Marzi A, Feldmann F, Haddock E, Brining D, Host response dynamics following lethal infection of rhesus macaques with Zaire ebolavirus. J Infect Dis. 2011;204(Suppl 3):S991–9. DOIPubMed
  8. Finney DJ. Statistical method in biological assay. New York: Macmillian Publishing Co., Inc.; 1978. p. 394–8.
  9. Towner JS, Rollin PE, Bausch DG, Sanchez A, Crary SM, Vincent M, Rapid diagnosis of Ebola hemorrhagic fever by reverse transcription–PCR in an outbreak setting and assessment of patient viral load as a predictor of outcome. J Virol. 2004;78:4330–41. DOIPubMed
  10. Bausch DG, Towner JS, Dowell SF, Kaducu F, Lukwiya M, Sanchez A, Assessment of the risk of Ebola virus transmission from bodily fluids and fomites. J Infect Dis. 2007;196(Suppl 2):S142–7. DOIPubMed
  11. Formenty P, Leroy EM, Epelboin A, Libama F, Lenzi M, Sudeck H, Detection of Ebola virus in oral fluid specimens during outbreaks of Ebola virus hemorrhagic fever in the Republic of Congo. Clin Infect Dis. 2006;42:1521–6. DOIPubMed
  12. Grolla A, Jones SM, Fernando L, Strong JE, Ströher U, Möller P, The use of a mobile laboratory unit in support of patient management and epidemiological surveillance during the 2005 Marburg outbreak in Angola. PLoS Negl Trop Dis. 2011;5:e1183. DOIPubMed
    Suggested citation for this article: Prescott J, Bushmaker T, Fischer R, Miazgowicz K, Judson S, Munster VJ. Postmortem stability of Ebola virus. Emerg Infect Dis. 2015 May [date cited]. http://dx.doi.org/10.3201/eid2105.150041
    DOI: 10.3201/eid2105.150041

    Astronomers Find Ancient Earth-Sized Planets in Our Galactic Backyard

    Posted date: 10:56 PM / comment : 0 , , , ,

    Sun-like star with orbiting planets, dating back to the dawn of the Galaxy, has been discovered by an international team of astronomers.
    At 11.2 billion years old, it is the oldest star with Earth-sized planets ever found and proves that such planets have formed throughout the history of the Universe.
    The discovery, announced on 28 January (AEDT) in the Astrophysical Journal, used observations made by NASA's Kepler satellite. The scientific collaboration was led by the University of Birmingham and contributed to by the University of Sydney.
    The star, named Kepler-444, hosts five planets smaller than Earth, with sizes varying between those of Mercury and Venus.
    "We've never seen anything like this -- it is such an old star and the large number of small planets make it very special," said Dr Daniel Huber from the University's School of Physics and an author on the paper.
    "It is extraordinary that such an ancient system of terrestrial-sized planets formed when the universe was just starting out, at a fifth its current age. Kepler-444 is two and a half times older than our solar system, which is only a youthful 4.5 billion years old.
    "This tells us that planets this size have formed for most of the history of the universe and we are much better placed to understand exactly when this began happening."
    Dr Tiago Campante, the research leader from the University of Birmingham said, "We now know that Earth-sized planets have formed throughout most of the Universe's 13.8-billion-year history, which could provide scope for the existence of ancient life in the Galaxy."
    Together with their international colleagues the University's astronomy team used asteroseismology to determine the age of the star and planets. This technique measures oscillations -- the natural resonances of the host star caused by sound waves trapped within it.
    They lead to miniscule changes or pulses in the star's brightness and allow researchers to measure its diameter, mass, and age. The presence and size of the planets is detected by the dimming that occurs when the planets pass across the face of the star. This fading in the intensity of the light received from the star enables scientists to accurately measure the sizes of the planets relative to the size of the star.
    "When asteroseismology emerged about two decades ago we could only use it on the Sun and a few bright stars, but thanks to Kepler we can now apply the technique to literally thousands of stars. Asteroseismology allows us to precisely measure the radius of Kepler-444 and hence the sizes of its planets. For the smallest planet in the Kepler-444 system, which is slightly larger than Mercury, we measured its size with an uncertainty of only 100km," Dr Huber said.
    "It was clear early on that we had discovered something very unusual because we had five planets orbiting a very bright star -- one of the brightest Kepler has observed. It is fantastic that we can use asteroseismology to date the star and determine just how old it is.
    "In the case of Kepler-444 the planets orbit their parent star in less than 10 days, at less than one-tenth the Earth's distance from the Sun. Their closeness to their host star means they are uninhabitable because of the lack of liquid water and high levels of radiation. Nevertheless, discoveries like Kepler-444 provide important clues on whether a planet that is more truly comparable to Earth may exist. "We're another step closer towards finding the astronomers' holy grail -- an Earth-sized planet with a one year orbit around a star similar to our Sun."
    A/c NASA, Astronomers using data from NASA's Kepler mission have discovered a planetary system of five small planets dating back to when the Milky Way galaxy was a youthful two billion years old.
    The tightly packed system, named Kepler-444, is home to five planets that range in size, the smallest comparable to the size of Mercury and the largest to Venus. All five planets orbit their sun-like star in less than ten days, which makes their orbits much closer than Mercury's sweltering 88-day orbit around the sun.
    Story Source:
    The above story is based on materials provided by University of Sydney.

    Read article on Science @ NASA

    Journal Reference:
    1. J. Ireland, R. T. J. McAteer, A. R. Inglis. CORONAL FOURIER POWER SPECTRA: IMPLICATIONS FOR CORONAL SEISMOLOGY AND CORONAL HEATING. The Astrophysical Journal, 2014; 798 (1): 1 DOI: 10.1088/0004-637X/798/1/1

    Bottled water

    Posted date: 9:29 AM / comment : 0 ,

    In almost all of North America, Western Europe, Australia, New Zealand and parts of Asia, it is safe to drink water straight out of the tap. (See which countries guarantee drinkable tap water).



    And yet, somehow, the manufacturers of bottled water have convinced us that unspeakable things might happen if we choose to drink from the tap. So successful has this marketing campaign been that worldwide, we spend more than $150 billion a year on bottled water. In the US, bottled water has outpaced milk, coffee, juice and alcohol to sit second only to soft drinks in packaged drink sales. It is projected to be number one by 2016.

    “But, but, but…” you protest, “bottled water is better! It’s fresh from the spring!”



    That’s where marketing comes in. With names and images that suggest the source of water is some pristine mountain spring, it’s easy to get taken in. Like this Aquafina label for example:


    But let’s zoom in and read the fine print, shall we? See the part I’ve underscored?


    I’ll repeat it if it’s too hard to read: “It originates from public water sources.”That’s right, it’s just filtered tap water.

    PepsiCo’s Aquafina isn’t the only brand to source water from the tap; other major brands like Coca-Cola’s Dasani and NestlĂ©’s Pure Life do the same. In fact, close to half of all bottled water is believed to be simply treated tap water. The only reason Aquafina, Pure Life and a few other brands mention it at all is because pressure from environmental groups forced them to cave in a few years ago.

    “Surely it’s safer than tap water? It says right there that it’s purified!”


    Several studies have shown that bottled water is likely no safer or cleaner than tap water. Comprehensive testing by the 
    ewg.org
    Environmental Working Group in 2008 revealed levels of contaminants in bottled water were around the same as in tap water. In fact, with some bottled brands, the levels exceeded legal limits. 

    In the US, tap water is regulated by the EPA, which has more stringent reporting standards than the Food & Drug Administration imposes on bottle water manufacturers. (The Facts About Bottled Water).

    Moreover, what the industry doesn’t emphasize is that bottles need to be refrigerated after opening (all water contains low levels of bacteria but these can multiply rapidly at room temperature) and bottles should also not be reused as bacteria can linger on the plastic. (Source: Health Canada).

    “But bottled water tastes better”


    Chalk up one more for marketing. Our senses have become shaped by what the ads tell us “pure water” tastes like. In countless blind taste tests—including one by the New York Times and several more by Corporate Accountability International (see storyofstuff.org), tap water came out ahead or on par with bottled water.

    “So how did we get convinced to drink bottled water?”


    Bottled water—specifically spring water—has been around for more than a century. However, as chlorination of water began making tap water consistently safe to drink, sales of bottled water began to decline in the early 20th century.

    That changed in 1977 when Perrier launched a $5 million marketing campaign for its imported water, which caught the imagination of yuppies with purchasing power. It went from luxury fad to mass commodity in 1994, when PepsiCo launched Aquafina and Coca-Cola followed soon after with Dasani. Prices dropped (the source being tap water obviously helped) and sales spurted. 

    Helped by suggestive advertising and aggressive marketing, bottled water was seen to be safer and more pure than what you could get for free (or close to it) from the tap. Some manufacturers even went so far as to claim bottled water was more environmentally friendly.





    Worth reading and watching:

    Right whales fart

    Posted date: 6:54 PM / comment : 0 , , ,

    You'll probably hear the parrotfish before you see them. The animals chomp through solid rock and coral with fused beaks. When you're snorkeling on one of Hawaii's reefs, the noise is unmistakable. Crunch, crunch, crunch.
    To watch the grazers at work, it would be easy to mistake parrotfish for the bad guys. Their chompers scar the reef with deep gouges and reduce what was once hard stone into nothing more than a cloud of sand, squirted unceremoniously out the fish's backsides.
    Yes, that is what happens.

    -->
    There are seven quintillion, five hundred quadrillion grains of sand in the world, according to math geniuses at the University of Hawaii. That’s more sand granules in Earth’s seas, lakes, and deserts than we could ever imagine.
    Where does it all come from? In Hawaii, where beaches are constantly ranked the best in the world, a significant portion of that pristine, white, beautiful sand is actually poop.
    Yep, poop.
    Parrotfishes, or uhu in Hawaiian, are key players in regulating algae and reef life. Their parrot-like beaks and fused-together teeth are used for scraping and biting dead coral, while additional teeth in their throats help to break it all down into sand. Snorkelers can actually hear them chomping or see the bite marks they leave on rocks.
    Because parrotfishes don’t have stomachs, their meals pass straight through the long intestine, exploding in a cloud of sand out the backdoor. Larger parrotfish are like sand factories, producing as much as 700 pounds of sand per year. For Oahu’s snorkeling hot spot, Hanauma Bay (where a few hundred parrotfish graze), that means hundreds of tons of fish-made sand per year.
    -->
    Worms, sponges, and oysters also produce Pacific ocean sand, but no animal is as proficient as the parrotfish, a badge of honor it has held for centuries. According to the Maui Ocean Center, the native Hawaiian name for the female redlip parrotfish translates to “loose bowels.”
    But according to Darla White, a marine scientist with Hawaii's Division of Aquatic Resources (DAR), parrotfish are actually integral to both the reefs' day-to-day health and long-term resiliency.
    "It's all about real estate on the reef," says White. "Every living thing is just looking for space, and each bite the parrotfish takes opens up an opportunity for coral larvae to settle in."
    Those bites are more valuable now than ever. Coral reefs thrive on clean, clear, low-nutrient water. But runoff from the islands contains fertilizers from farms and lawn care, and these excess nutrients cause both naturally occurring and invasive algae to go haywire. Before you know it, all the available real estate is shellacked with fast-growing algae, and the extremely slow-growing coral can't colonize these surfaces. Parrotfish keep these blooms in check by beak-biting straight down to the substrate.
    (Jeffrey L. Rotman/Corbis)
    Unfortunately for the reefs, parrotfish are freaking delicious. They are also beautiful. And that means the fish are a prized target of both subsistence-, sport-, and even some commercial-fisherman. Most herbivores don't take a hook, but spearfishing and nets work well enough. Add to this the unfortunate fact that many species of parrotfish are also really heavy sleepers, and you can see there's a problem. At night, they secrete a layer of mucous across their body that's thought to protect them from parasites and perhaps keep predators from sniffing them out. But it does nothing to prevent unscrupulous night divers from plucking the fishies from the reef like cooling pies off the proverbial windowsill.
    To combat these pressures, White and her colleagues at the DAR designated part of the reef along West Maui's coast as the Kahekili Herbivore Fisheries Management Area in 2009. This made it illegal to kill or injure several species of herbivorous fish, including parrotfish, surgeonfish, and sea chubs, as well as sea urchins anywhere in the preserve. After several years of watching and waiting, they analyzed the results in 2012 and reported that parrotfish biomass had actually doubled. What's more, they found a strong positive relationship between total parrotfish biomass and the amount of coral growing on the reef.
    Problem is, White says only 1 percent of Hawaii's coral reefs are under this kind of protection — which means most of the region's parrotfish are getting picked off before they can even reach full size. And this is a problem, because when it comes to parrotfish reproduction, size matters.
    Hawaii's parrotfish live in harems — one guy to half a dozen or more gals — but every fish begins its life as a female. If the harem's male gets speared by a diver or otherwise decides to go out for a pack of smokes, the most dominant female can, over time, turn herself into a male.
    You can tell when a female is going through this miraculous transformation because she will start to change from a dull gray to the more striking blues, greens, and purples of parrotfish males. And because the change doesn't just simply happen overnight, it's not uncommon to see a parrotfish swimming around that's half gray (female) and half green (male).
    -->
    Before the color change is complete, some species of parrotfish use their half-and-half status as camouflage, deftly sneaking into harems that still have a super-male and fertilizing the females' eggs before the alpha fish knows what's up. (Note: This is known as "streaking" (through the Quad), and it's a good way to get your ass beat. Parrotfish are highly territorial.)
    It should come as no surprise then that the biggest, beefiest, most flamboyantly colored parrotfish — which you now know to be exclusively male — are at the highest risk of human predation. This makes repopulating the reefs with algae-eaters all the more difficult, since males aren't simply hatched — they're built, over time and circumstance.
    "It's human nature to try to fix something once it's broken," says White, regarding the state of Hawaii's reefs. "But to try to fix an entire ecosystem, especially one that's in the water? It's not easy."
    But that won't stop them from trying. The DAR has partnered up with organizations like the Coral Reef Alliance and local businesses like The Snorkel Store to educate policymakers and actually get them in the water to see what's at stake. They've worked with hotels and landscapers to raise awareness about runoff. And the Coral Reef Alliance established something called the Fish-Friendly Business Alliance, which promotes businesses that don't sell fish food — because if grazers are eating pellets out of the hands of tourists, they don't have to eat as much algae.
    Whether it's reducing algae and pollution or giving parrotfish populations a chance to rebound, the goal is to return Hawaii's reefs back to some semblance of balance — or lokahi, as the locals might say. Here on the mainland, I think that translates to, "You break it, you bought it."

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