Unlikely Critters Found in Avocado Orchards

journal.pone.0068025.g002Wildlife isn’t always restricted to wild spaces.

Avocado orchards and other agricultural landscapes also buzz with species that forage and reproduce in these spaces. Birds and herbivores are able to find food and shelter in these cultivated areas, but what about carnivores?  In a study published this week in PLOS ONE, researchers at the University of Washington have discovered that mammalian carnivores also occupy avocado orchards in southern California.

The authors used motion-activated cameras to observe animals in orchards and in adjacent wild lands in Santa Barbara and Ventura.  Avocado orchards were of particular interest due to their location near native vegetation.

Through their investigation, the researchers detected more carnivores in the avocado orchards than in neighboring wild land sites. At least 7 out of the 11 native carnivores in the area were spotted roaming the orchards, including coyotes, gray foxes and bobcats.3561367265_093313316f

Having delicious avocados handy may explain why some omnivores such as bears and raccoons are present in the area, however, little is known about why animals like bobcats and mountain lions might leave their wild habitat for cultivated land. One possibility is that the orchards provide water and fruits for herbivores, and an increased herbivore population could translate to more prey for the carnivores. The orchards may also serve as shelter, offering forest cover similar to oak woodlands in the area.

These native species cannot always persist in protected reserves, so it is important to learn how cultivated lands can serve their lifestyle and behaviors. The carnivores may not be searching for the perfect guacamole ingredient; however there is no doubt that the avocado orchards are serving as a habitat for a wide range of species.

Citation: Nogeire TM, Davis FW, Duggan JM, Crooks KR, Boydston EE (2013) Carnivore Use of Avocado Orchards across an Agricultural-Wildland Gradient. PLoS ONE 8(7): e68025. doi:10.1371/journal.pone.0068025

Image 1: doi:10.1371/journal.pone.0068025

Image 2: Image on Flickr by Graeme Churchard

The Rhinoceros: Saving an Icon

8526743557_5c3a36734eThe rhino is an iconic animal. With their tough demeanor and unforgettable horn, what’s not to love?

This majestic creature has been on earth more than 9.2 million years, according to a recent PLOS ONE article, where researchers describe a fossil belonging to a large two-horned rhinocerotine species in central Turkey.  This rhino was preserved in volcanic rock, a process which accounts for less than two percent of the earth’s fossils. The scientists believe an eruption similar to that of Mt. Vesuvius must be responsible for the impeccable preservation. This study gave us a sense of just how long these brilliant beasts have been among us; however their existence is in grave danger today.

Yesterday May 1st, was Save the Rhino day. The purpose of this day is to bring awareness to rhino conservation and the threats this animal faces in the wild. The rhinoceros does not have any known predators, except for us! Humans have been poaching the rhino at astounding rates for their distinctive horn. The horn is made of keratin, the same protein in our finger nails and hair, and is thought to offer health benefits in traditional medicine. The horn has also been poached for luxury items in other parts of the world.

Today, there are fewer than 29 thousand rhinos on earth, with the white rhino on the brink of extinction. In a recent PLOS ONE article, authors have investigated how potential losses in conservation efforts would affect the white rhino population in South Africa. The authors specifically looked into Kruger National Park where the rhino population increased from 1998 to 2008. Despite this increase, researchers have predicted that by 2015 more white rhinos will be poached than bred, bringing the species into a negative growth phase. Due to the high demand for rhino horns, the authors urge conservationists to find innovative approaches to curb the financial incentive driving the poaching.

Global awareness and conservation is desperately needed to ensure the rhinoceros continues to graze the earth for millions of years to come. For more research on conservation and the glorious rhinoceros, visit our site here.

 

Citations:

Citation: Antoine P-O, Orliac MJ, Atici G, Ulusoy I, Sen E, et al. (2012) A Rhinocerotid Skull Cooked-to-Death in a 9.2 Ma-Old Ignimbrite Flow of Turkey. PLoS ONE 7(11): e49997. doi:10.1371/journal.pone.0049997

Citation: Ferreira SM, Botha JM, Emmett MC (2012) Anthropogenic Influences on Conservation Values of White Rhinoceros. PLoS ONE 7(9): e45989. doi:10.1371/journal.pone.0045989

Image on Flickr by wwarby

Tuberculosis: Raising Awareness Through Research

One of the world’s deadliest infectious diseases has been with us since the time of the ancient Greeks and Romans. It has been found in thousand-year-old Egyptian mummies and is still present in millions of homes today. What is this ancient disease you may ask? Tuberculosis.

Pulmonary tuberculosis (TB) is a contagious bacterial infection in the lungs, which can spread to other organs. According to the CDC, TB is one of the most common infectious diseases in the world. And although significant progress has been made to eliminate this illness, 9 million new cases of tuberculosis were reported in 2011.

Tuberculosis is spread when an individual is exposed to a sneeze or cough of a person suffering from the disease. TB can also be contracted if someone has poor nutrition or living conditions.  In some cases, the infection can lie dormant in the body for years, and in others, it may become active and cause major complications. The primary stage of tuberculosis has no symptoms, but as the disease progresses, patients can suffer from bloody coughs, fatigue, fever and weight loss.

Ancient Roman physicians recommended treatments including bathing in human urine, eating wolf livers and drinking elephant blood. Today, though, modern medicine has found that Tuberculosis is preventable and treatable by more modern methods,  with early treatment being essential to stopping its progression.

In honor of World TB Day, observed yesterday on March 24th, here are some recently published papers from PLOS ONE on the subject:

Diabetes is a risk factor for TB, and it can also affect the severity of the infection and success of treatment. In a recent study, authors have researched the connection between diabetes, smoking and tuberculosis.  The cohort study featured patients suffering from their first episode of tuberculosis. Out of the 657 participants analyzed, diabetes was present in 25 percent, which increased the risk of death in the first 12 months after enrollment. Tobacco smoking also increased the risk of TB and caused further complications among diabetic patients.

In another recently published paper, researchers have investigated the outcome of aggressive treatments for multidrug-resistant tuberculosis. The patients analyzed were treated in a national outpatient program in Peru from 1999 to 2002. Participants received individualized regimens for laboratory-confirmed tuberculosis.  In this cohort examination, authors found that TB was cured in 66 percent of the patients, showing that aggressive regimens for multidrug-resistant tuberculosis can be extremely successful.

Lastly, the link between poverty and TB has been well established, but the mechanisms behind this link have not.  In a third PLOS ONE paper, authors investigated why the poor are at a greater risk for tuberculosis in India.  With data from the 2006 Demographic Health Survey, researchers analyzed incidences of TB and household economic status. They found low body mass index and air pollution may be partly responsible for the link between poverty and tuberculosis.

Further initiatives are needed to assist in the global eradication of tuberculosis. To expand your own awareness of this infectious disease, please explore additional PLOS ONE research here.

 

Citations:

Reed GW, Choi H, Lee SY, Lee M, Kim Y, et al. (2013) Impact of Diabetes and Smoking on Mortality in Tuberculosis. PLoS ONE 8(2): e58044. doi:10.1371/journal.pone.0058044

Mitnick CD, Franke MF, Rich ML, Alcantara Viru FA, Appleton SC, et al. (2013) Aggressive Regimens for Multidrug-Resistant Tuberculosis Decrease All-Cause Mortality. PLoS ONE 8(3): e58664. doi:10.1371/journal.pone.0058664

Oxlade O, Murray M (2012) Tuberculosis and Poverty: Why Are the Poor at Greater Risk in India? PLoS ONE 7(11): e47533. doi:10.1371/journal.pone.0047533

Image: By isafmedia on Flickr

Cervical Health Awareness Month

Health risks can be frightening, but ignorance to these risks can be even more terrifying. In the past, we have discussed a range of women’s health issues, including obesity, cardiovascular disease and ovarian cancer.  To continue our commitment to health awareness, we would like to honor January as Cervical Health Awareness month.

PLOS ONE has published research tackling many aspects of cervical health, including cervical cancer and human papillomavirus.

Human papillomavirus, better known as HPV, is the most common sexually transmitted virus in the United States. According to the U.S. Center for Disease Control, at least 50% of sexually active people will contract the virus at some point in their lives.  There are more than 40 types of HPV, some of which may lead to cervical cancer. Cervical cancer is highly preventable with regular screening and vaccination to help prevent human papillomavirus.

To further expand our knowledge and understanding of cervical health, researchers from across the globe continue to explore HPV, the vaccine and its social effects.

For example, in a study published in PLOS ONE, authors in Tanzania explored the reasoning behind young girls receiving or not receiving the HPV vaccination. After interviewing both adults and students, researchers found that vaccine education and parental meetings were crucial for vaccine acceptance. Knowing women who had suffered from cervical cancer was also a factor in the decision-making.

The effectiveness of the vaccine is also a common concern. In another article, Canadian researchers developed a system to track the effectiveness of the HPV vaccination in preventing the virus.  The authors created a protocol for linking multiple data registries to allow for ongoing monitoring of the vaccines effectiveness, while also ensuring patient privacy was taken into account. This research aims to understand the long term effects of the vaccine and future vaccination tracking initiatives.

This study expands our knowledge on the vaccination results, but what about transmission of the virus? In a third PLOS ONE report, researchers explored the prevalence of HPV in the DNA of males with infected female sexual partners.  The authors found that HPV was prevalent in 86% of the male participants surveyed. These men had the same high risk viral type as the infected women, supporting the importance of awareness in men to protect themselves and their partners. This area of investigation is important in expanding our knowledge of transmission of the virus and the risk of cervical cancer development.

All these studies are aimed at improving our understanding of HPV risks and vaccination, and there are many more. As Cervical Health Awareness month draws to an end, explore more PLOS ONE research on the subject here.

 Citations:

Watson-Jones D, Tomlin K, Remes P, Baisley K, Ponsiano R, et al. (2012) Reasons for Receiving or Not Receiving HPV Vaccination in Primary Schoolgirls in Tanzania: A Case Control Study. PLoS ONE 7(10): e45231. doi:10.1371/journal.pone.0045231

El Emam K, Samet S, Hu J, Peyton L, Earle C, et al. (2012) A Protocol for the Secure Linking of Registries for HPV Surveillance. PLoS ONE 7(7): e39915. doi:10.1371/journal.pone.0039915

Rocha MGdL, Faria FL, Gonçalves L, Souza MdCM, Fernandes PÁ, et al. (2012) Prevalence of DNA-HPV in Male Sexual Partners of HPV-Infected Women and Concordance of Viral Types in Infected Couples. PLoS ONE 7(7): e40988. doi:10.1371/journal.pone.0040988

Image: Glass sculpture of human papillomavirus.  Photograph by Luke Jerram, “Papilloma 2011″


Prowling Catfish Catch Pigeons on Land

Cats hunt birds, and sea-birds hunt fish.  And in some odd ecological pockets, catfish hunt pigeons.

In a study published today by researchers at the University of Toulouse, France, scientists have investigated this unusual predator-prey relationship between European catfish and pigeons in the Southwest region of France.

European catfish have been reported to capture the pigeons on land and drag them back into the water.  This surprising behavior has not been known to occur in the native range of the species; however this article discovers that in France, where the fish are an invasive species, they have adapted their natural behavior in order to feed on novel prey in their new environment.

The researchers completed this study along the Tarn River in Southwestern France.  European catfish originate from Europe, east of the Rhine River, but were introduced to the Tarn River in 1983.

From a bridge above a gravel island on the river, the researchers watched the fish from June through October 2011. Over that time they saw 54 pigeon hunting incidents, and in 28% of these cases, the catfish successfully captured their prey on land and dragged them back into the water to eat them. These attacks were nearly always triggered by active pigeons, as catfish never attacked motionless pigeons. This evidence suggests that the catfish used water vibrations to hunt their prey rather than visual cues.

The cause of this unusual predation behavior is still unknown. However, these new findings may bring us closer to understanding the implications of such novel behavior in a new ecosystem.

To view the fascinating catfish behavior described in this article, please see the video below:

Citation: Cucherousset J, Boulêtreau S, Azémar F, Compin A, Guillaume M, et al. (2012) “Freshwater Killer Whales”: Beaching Behavior of an Alien Fish to Hunt Land Birds. PLoS ONE 7(12): e50840. doi:10.1371/journal.pone.0050840

Spiders, Birds, and Snakes, Oh my!

To continue our spooktacular posts this October, we bring you a study which may have some arachnophobes rethinking their next vacation destination.

The island of Guam is home to one of the densest spider communities in the Pacific.  In a recent study published with PLOS ONE, researchers investigated this region to discover how the demise of insectivorous birds inhabiting the island has affected one of the most widely feared creepy crawlers.

The downfall of Guam’s native insect-eating birds began in the 1940’s when the infamous brown tree snake was introduced.  To investigate the effects this loss had on the landscape, the authors of the recent paper analyzed the spider population on several Pacific islands.

The team compared the neighboring islands of Rota, Tinian and Saipan, to Guam. These islands do not have any known snake populations, and also have similar native bird species to that of Guam.  The researchers were then able to assess whether the bird presence correlated with spider web numbers, in addition to what impact bird presence had per season.

What the authors found might send chills right down your spine: The spider web densities in Guam were 40 times higher than those of the other islands during the wet season. Guam had an average of 18.37 spider webs per 10 meters, as compared to the other islands, which only had 0.45 webs per 10 meters. In addition, the bird loss had even increased the web size for a certain spider species.

Whether you suffer from arachnophobia, ophidiophobia (fear of snakes) or ornithophobia (fear of birds), I think we can all agree this is a terrifying case showing the effects the removal of an essential predator can have to a landscape.

Citation: Rogers H, Hille Ris Lambers J, Miller R, Tewksbury JJ (2012) ‘Natural experiment’ Demonstrates Top-Down Control of Spiders by Birds on a Landscape Level. PLoS ONE 7(9): e43446. doi:10.1371/journal.pone.0043446

Image Credit: Anders B on Flickr CC-by license