or disabled by the disease a parasitic-worm infection spread by mosquitoes. Our study quantifies the effect of the most widely implemented vector control measure--insecticide-treated bed nets
but did not stop its transmission by mosquitoes. The success of a strategy utilizing medication requires at least 80 percent of the population to receive treatment annually for at least five years.
Testing showed that parasite levels remained high in mosquitoes around the villages as much as decade later.
they could find no mosquitoes harboring parasites capable of transmitting the disease. Insecticide-treated bed nets already are used widely in areas where lymphatic filariasis
They block female mosquitoes from securing blood a process that is essential for them to lay eggs and produce offspring.
The insecticide reduces the life-span of the insect by half preventing it from living long enough for the parasite to become capable of transmission.
The researchers also discovered that the bed nets caused the insects to alter their biting behavior.
and 2: 00 a m. When the mosquitoes bite earlier in the day they ingest fewer parasites
or female and rely completely on host specific insect pollinators--so a lone cycad that dispersed a long way from others of its kind would probably be disadvantaged rather than advantaged in terms of reproduction.
While much previous research has focused on trying to create a superbug that could tackle the whole job of processing waste plant materials into biofuels Lin
In these dry fragile ecosystems where increase in water availability from rainfall is the limiting factor for malaria transmission irrigation infrastructure can drastically alter mosquito population abundance to levels above the threshold needed to maintain malaria transmission said lead
when irrigation is introduced due to increased amounts of standing water that serve as mosquito breeding sites.
and characterized by an enhanced environmental malaria risk despite intensive mosquito control efforts said Pascual the Rosemary Grant Collegiate Professor of Ecology and Evolutionary Biology at U-M and a Howard
which is transmitted via the bites of infected Anopheles mosquitoes. In the human body the parasites multiply in the liver
or OMPS that flies aboard the Suomi-NPP satellite measures relative aerosol concentrations such as those generated by wildfires.
and recover from EAB invasion with research on the insect ash trees'resistance to EAB and biological control.
These areas included sites approximately 50-100 km from the EAB epicenter where the insect had caused some tree mortality but considerably less than
because the timing of their food--insect hatches greening plants for example--no longer coincides with their travel this can have serious consequences for their continued survival.
#Medfly and other fruit flies entrenched in California, study concludesresearch published today in the international journal Proceedings of the Royal Society B clearly demonstrates that at least five and as many as nine species of tropical fruit flies including the infamous Medfly are established permanently in California
and inexorably spreading despite more than 30 years of intervention and nearly 300 state-sponsored eradication programs aimed at the flies.
The new study by a trio of scientists affiliated with the University of California Davis has significant implications for how government agencies develop policies to successfully manage pests that pose a threat to California's $43. 5 billion agricultural industry.
and establishment of these insects virtually all of the fruit-fly species targeted by eradication projects have been reappearing in the same locations--several of them annually
--and gradually spreading in the state said UC Davis entomology professor James Carey an international authority on fruit-fly invasion biology
which examined more than 60 years of state fruit-fly capture data. Regulatory policies as well as pest management and agricultural practices need to be revised to reflect the reality that these insects are here to stay.
We need to develop long-term strategies to deal with these pests that are effective safe for public and environmental health
Fortunately the multiple small populations of fruit flies in the state and the long lag times in the growth of these populations will give policymakers
This work is the most comprehensive analysis of populations of tropical fruit flies in California to date
and in any region worldwide said insect population biologist George Roderick the William Muriece Hoskins professor
Frank Zalom incoming president of the Entomological Society of America and a UC Davis entomology professor said the new study provides a careful and systematic analysis of fruit-fly finds
I hope that it helps lead to new discussions on a long-term approach for dealing with fruit flies
and European nations with conditions equally hospitable to fruit flies as well as similar patterns of international travel and detections of fruit flies in cargo at ports of entry do not have established fruit-fly populations.
This combination of findings definitively rebuts the hypothesis that the multiple detections of many species of fruit flies in California each year are the result of repeated new introductions he said.
Papadopoulos the study's lead author and an internationally renowned expert on fruit-fly demography and invasion biology was formerly a postdoctoral fellow
and visiting scholar at UC Davis. These findings may have wider implications regarding management of fruit-fly invasions that may go well beyond California Papadopoulos said.
and possibly several more fruit-fly species are established in California said Plant who provided mathematical modeling and statistical analysis for the study.
The researchers applied computerized data-mapping technology to analyze historical fruit-fly detection data. Using this analysis they determined that besides the olive fly
which is confirmed as established the Mediterranean Mexican oriental melon peach and guava fruit flies are established now also in California.
Fruit-fly history in Californiatropical fruit flies have been a concern to California for nearly 60 years with the first fruit fly discovered here in 1954.
Since then 11386 individual flies including adults and larvae representing 17 different fruit-fly species have been detected in nearly all regions of the state.
Both adult and larval fruit flies pose a threat with the larvae (maggots) actually burrowing into
and damaging a wide range of fruits and vegetables. Because of the state's geographic location and climate California is considered particularly vulnerable to introduction and establishment of tropical fruit-fly populations.
The pests were thought to be arriving either on cargo shipments or on infested fruits carried in by travelers from regions of the world where fruit flies were had native
or become established. State and federal agencies have for many years coordinated efforts to prevent the invasive fruit flies from establishing breeding populations in California and other vulnerable states.
Such activities include restricting commodity imports from regions with ongoing fruit-fly outbreaks requiring postharvest treatments for produce grown in areas with established fruit-fly populations maintaining large-scale fruit-fly monitoring programs for early detection
and release of sterile fruit flies to slow or prevent reproduction of the invasive flies. The potential costs associated with established fruit-fly populations are substantial.
For example a 1995 study estimated that a confirmed Medfly establishment alone in California would result in $493 million to $875 million in annual direct costs
and the imposition of a related embargo on shipping fruits and vegetables from the state would cause an additional loss of $564 million.
The state economy could lose $1. 2 billion in gross revenue and more than 14000 jobs the earlier study suggested.
New study findingsin the new published study the researchers report that several lines of evidence now indicate that the fruit flies have become self-sustaining
and thus established in California including: Collectively the data suggest that much like other invasive species tropical fruit flies can be present in low numbers for decades Carey said.
This'lag time'which is such a hallmark of invasion biology explains why California can be harboring very small established populations of these pests with only periodic captures that reveal their presence.
He noted that two aspects of the fruit-fly invasions are advantageous for policymakers and planners:
all detected fruit-fly species are extremely small and may continue to exist for years below detectable levels
and the fairly long lag times provide opportunities for developing new management protocols and programs.
Suggested responsecarey said that an immediate assessment should be made of the economic impact of having each species established in the state projecting the individual and collective effects of the fruit flies for all affected California fruit and vegetable crops.
He also suggests that government agencies might increase fruit-fly monitoring particularly in the Central Valley and California's other agriculturally important areas;
establish fruit-fly-free zones in the state to assure trading partners; and enable farmers to purchase crop insurance that would provide protection against losses due to fruit-fly crop damage
or marketing restrictions. In addition California farmers and packers should consider the presence of established fruit-fly populations
when developing their cropping plans and production strategies he said. In the scientific arena Carey recommends that genetic analyses be developed for all of the fruit-fly species identified in the state to determine
whether single or multiple invasions of each species are occurring and identify new strains that might be introduced in the future.
I predict this paper will be remembered as much for its future impact on how science is used in developing strategies for pest management worldwide as for the conclusions it draws about the state of tropical fruit-fly populations in California he said.
The researchers contrasted their findings with gene-regulation data from another model organism Drosophila to see where the similarities lay.
They found that there were a lot more differences between closely related mouse strains than there are between distantly related fruit-fly strains.
while fruit flies have relatively little. So a mouse's regulatory wiring will just have a lot more wiggle room than a fruit fly's says Paul.
That gives us a clearer picture of what we can expect to learn about mammalian genetic regulation from fruit flies.
The study could help scientists understand how gene regulation differs from one person to the next explaining why genes that cause disease in some people don't have that effect in others.
#Temperature alters population dynamics of common plant peststemperature-driven changes alter outbreak patterns of tea tortrix--an insect pest
whether insects emerge as cohesive cohorts or continuously according to an international team of researchers. These findings have implications for both pest control
and the timing of the various insect life stages which is critical for scheduling pest control.
The researchers looked at more than 50 years of data on the tea tortrix and also developed an independent mathematical population model that can predict population dynamics under both constant and seasonally driven temperature regimes.
While the tea tortrix is native to Japan many similar moths exist in North american including the spruce bud moth grape berry moth light brown apple moth and summer fruit tortrix.
The researchers who also include William A. Nelson associate professor of biology Queens University Canada currently on sabbatical at Penn State and Takehiko Yamanaka senior researcher National Institute for Agro-Environmental sciences Tsukuba
Japan used long-term data on the population dynamics of the tea tortrix that span 51 years and more than 200 outbreaks.
This type of insect remains dormant during the winter and emerges once the temperature reaches a certain level in the spring.
Because the first generation is triggered by this temperature increase the insects emerge all at once. We found the tea tortrix data very interesting said Bjã¸rnstad.
Often in North america we have one or two discrete early cohorts because winter synchronizes them
The tea tortrix starts out in this way but the researchers found that desynchronization does not occur.
and the developmental rate of the tea tortrix is said high Bjã¸rnstad. The population grows very fast
To better understand how temperature influences tea tortrix and other insect populations the researchers developed a mathematical population model that is based on the insect life cycle
and the effects of temperature on individual stages and used this to predict population dynamics.
The model is developed to represent the biology of the insect said Nelson. It is developed realistic fully and parameterized independently of the field data.
This is the first clear demonstration that temperature has the ability to alter those dynamics causing large cycles in the insect.
Heat enables the smell to go farther attracting more pollinating insects and increasing the chance of pollination.
The data provided by this series of photographs will help us understand how the Titan arum uses thermal energy to attract pollinators said Taber.
#Mini-monsters of the forest floora University of Utah biologist has identified 33 new species of predatory ants in Central america and the Caribbean and named about a third of the tiny but monstrous-looking insects
These new ant species are the stuff of nightmares when viewed under a microscope says entomologist Jack Longino a professor of biology.
and refers to the club-shaped hairs on many Eurhopalothrix (pronounced you-row-pal-oh-thrix) species. In another upcoming study accepted for publication in the same journal Longino identified 19 new ant species from the genus
and described differences from 15 other previously known species. The genus name means eight swellings for the ants'eight-segmented antennas.
The new ant species are less than one-twelfth to one-twenty-fifth of an inch long--much smaller than a rice grain
or common half-inch-long household ants --and live in the rotting wood and dead leaves that litter the forest floors in Central america.
No one knows how they find their prey presumed to be bodied soft insects spiders millipedes and centipedes.
But the ants are known to coat themselves with a thin layer of clay believed to serve as camouflage.
Ants are everywhere Longino says. They are one of the big elements of ecosystems like birds and trees.
Some act as predators and influence the population sizes of other insects by eating them. They gather a lot of dead insects
and eat them so they are like vultures at a microscale. They move seeds around
So far there are about 15000 known species of ants worldwide based largely on difference in body structure and perhaps as many as 30000.
But as geneticists analyze more and more ants new genetic differences are becoming apparent and so there could be 100000 ant species Longino said.
The world has known some 700000 insect species but that number likely will climb much higher as more are discovered.
Longino says 70 percent to 80 percent of all known species are insects. The 33 new species bring the number of ant species Longino has discovered during his career to 131.
The adult ants eat only liquids not solid food. So they bring their prey back to the nest where it is eaten by ant larvae
Most modern ants no longer are predators some of which use venoms to sting their prey but instead are scavengers like those that pick up crumbs off kitchen floors
and spray formic acid to fight off other ants. Sifting for Antslongino collected about 90 percent of the ants in his new studies during the past 30 years working on a series of projects to inventory insects spiders
and other arthropods in Costa rica Mexico Nicaragua Guatemala and Honduras. Many of the species also are in the Caribbean and South america.
The new ant species are not agricultural pests. To collect insects Longino and his students use sifting devices that look somewhat like a pair of tennis rackets with canvas bags beneath them.
The researchers use machetes to chop up dead wood and leaf litter and pour it through sifters
The tiny ants end up in the collection bags with what looks like potting soil. This mixture then is placed in mesh bags suspended over funnels that in turn are above plastic bags containing alcohol to kill
and preserve the ants that pass through the mesh bags. The ants then are brought home for analysis. Taxonomy
or classification of living things is in frequent flux. Longino says he thinks of species as hypotheses not definite never-changing labels.
and perhaps redefine classifications for ants in four or five ant genuses or genera. Some species are likely to end up in a different genus after such research is done he says.
The berry bushes also produce flowers of value to pollinators like butterflies insects and hummingbirds; food for other small and large mammals;
which make use of so-called entomopathogenic viruses that are harmful to insects in particular the baculovirus.
To identify the virus in this family that will most effectively control the Guatemalan potato moth The french-Ecuadorian research team have analysed the pathogens among moths from all over the world.
The researchers detected it in moths from twelve different countries. Moreover it has the widest activity spectrum:
it produces a mortality rate among Guatemalan potato moth larvae of more than 98%!%Slow action#Pulverised on the surface of potatoes or the eggs of the invasive species the granulovirus contaminates the larvae through ingestion.
Its use also requires expert knowledge and detailed monitoring of the moth's biological cycle ecology and behaviour
Moreover each viral strain attacks a very limited number of insect species. This host specificity means that the Guatemalan potato moth can be targeted
while preserving the ecosystem in particular useful insects like pollinators. Lastly unlike the molecules in chemical plant-protection products viruses are able to mutate which limits the development of resistance in their host.
Need for an integrated control strategyfor efficient control of the Guatemalan potato moth the use of this viral pesticide must therefore necessarily form part of an integrated control strategy.
molecular analyses to describe the genetic structure of the pests a study of the impact of temperatures on their ecology by means of drones with thermal cameras#The aim is to get a better understanding of the insects'population dynamics
The study published July 24 in the online journal PLOS ONE is the first analysis of real-world conditions encountered by honey bees as their hives pollinate a wide range of crops from apples to watermelons.
The researchers collected pollen from honey bee hives in fields from Delaware to Maine. They analyzed the samples to find out which flowering plants were the bees'main pollen sources and
because they're not designed to kill insects vanengelsdorp said. Federal regulations restrict the use of insecticides
while pollinating insects are said foraging he but there are no such restrictions on fungicides so you'll often see fungicide applications going on
In an unexpected finding most of the crops that the bees were pollinating appeared to provide their hives with little nourishment.
Honey bees gather pollen to take to their hives and feed their young. But when the researchers collected pollen from bees foraging on native North american crops such as blueberries and watermelon they found the pollen came from other flowering plants in the area not from the crops.
whether an oil palm plantlet is a high-yielding palm Even with selective breeding 10 to 15 percent of plants are the low-yielding dura form due to uncontrollable wind and insect pollination particularly in plantations
#Populations of grassland butterflies decline almost 50 percent over two decades: European reportgrassland butterflies have declined dramatically between 1990 and 2011.
This has been caused by intensifying agriculture and a failure to properly manage grassland ecosystems according to a report from the European Environment Agency (EEA).
In the report the data of the Butterfly monitoring scheme in Germany have been incorporated which is supported scientifically by the Helmholtz Centre for Environmental Research (UFZ).
The fall in grassland butterfly numbers is particularly worrying according to the report because these butterflies are considered to be representative indicators of trends observed for most other terrestrial insects
which together form around two thirds of the world's species. This means that butterflies are useful indicators of biodiversity and the general health of ecosystems.
Seventeen butterfly species are examined in'The European Grassland Butterfly Indicator: 1990-2011'comprising seven widespread and 10 specialist species. Of the 17 species eight have declined in Europe two have remained stable and one increased.
For six species the trend is uncertain. Butterflies examined in the report include the Common Blue (Polyommatus icarus)
which has declined significantly the Orangetip (Anthocharis cardamines) which seems to be stable since 1990 and the Lulworth Skipper (Thymelicus acteon)
This dramatic decline in grassland butterflies should ring alarm bells--in general Europe's grassland habitats are shrinking.
We must recognise the importance of butterflies and other insects--the pollination they carry out is essential for both natural ecosystems and agriculture.
Why are butterflies disappearing? Intensifying agriculture and abandoned land are the two main trends affecting the populations of grassland butterflies.
Agriculture has intensified where the land is relatively flat and easy to cultivate and on the other handlarge areas of grasslands have been abandoned in mountainous and wet regions mainly in eastern and southern Europe.
Both intensification and abandonment result in the loss and degradation of habitat for grassland butterflies.
Agricultural intensification leads to uniform grasslands which are almost sterile for biodiversity. In addition butterflies are also vulnerable to pesticides often used in intensively managed farming systems.
Farmland is abandoned often for socioeconomic reasons. When farming on low-productivity land brings only a small amount of income
In some regions of northwestern Europe grassland butterflies are restricted now almost to road verges railway sidings rocky or wet places urban areas and nature reserves.
Monitoring Europe's butterfliesthe report is based on the European Grassland Butterfly Indicator compiled by De Vlinderstichting (Dutch Butterfly Conservation) Butterfly Conservation Europe
The indicator brings together information from national butterfly monitoring schemes in 19 countries across Europe most of them European union Member States.
Thousands of trained professional and volunteer recorders count butterflies on approximately 3 500 transects scattered widely across Europe.
This volunteer fieldwork is essential for understanding the state and trends of Europe's butterflies.
The report therefore suggests that the recent halving of butterfly numbers may be the most recent development in a much bigger long-term decline.
The European Grassland Butterfly Indicator could be used as a measure of success of agriculture policies.
Sustainable funding of butterfly indicators would help validate and reform a range of policies and help achieve the goal of halting the loss of biodiversity by 2020.
when pollinator species declineremove even one bumblebee species from an ecosystem and the impact is swift and clear:
The study to be published by the Proceedings of the National Academy of Sciences focused on the interactions between bumblebees and larkspur wildflowers in Colorado's Rocky mountains.
The results show how reduced competition among pollinators disrupts floral fidelity or specialization among the remaining bees in the system leading to less successful plant reproduction.
We found that these wildflowers produce one-third fewer seeds in the absence of just one bumblebee species says Emory University ecologist Berry Brosi who led the study.
That's alarming and suggests that global declines in pollinators could have a bigger impact on flowering plants
The National Science Foundation (NSF) funded the study co-authored by ecologist Heather Briggs of the University of California-Santa cruz. About 90 percent of plants need animals mostly insects to transfer pollen between them
Bees are by far the most important pollinators worldwide and have evolved co with the floral resources they need for nutrition.
Some studies have indicated that plants can tolerate losing most pollinator species in an ecosystem as long as other pollinators remain to take up the slack.
Those studies however were based on theoretical computer modeling. Brosi and Briggs were curious whether this theoretical resilience would hold up in real-life scenarios.
Their team conducted field experiments to learn how the removal of a single pollinator species would affect the plant-pollinator relationship.
Most pollinators visit several plant species over their lifetime but often they will display what we call floral fidelity over shorter time periods Brosi explains.
because a pollinator visit will only lead to plant reproduction when the pollinator is carrying pollen from the same plant species
. When bees are promiscuous visiting plants of more than one species during a single foraging session they are much less effective as pollinators Briggs says.
The researchers conducted their experiments at the Rocky mountain Biological Laboratory near Crested Butte Colorado. Located at 9500 feet the facility's subalpine meadows are too high for honeybees
but they are buzzing during the summer months with bumblebees. The experiments focused on the interactions of the insects with larkspurs dark-purple wildflowers that are visited by 10 of the of the 11 bumblebee species there.
The researchers studied a series of 20-meter square wildflower plots evaluating each one in both a control state left in its natural condition
and in a manipulated state in which they used nets to remove the bumblebees of just one species. The researchers then observed the bumblebee behavior in both the controlled plots
and the manipulated plots. We'd literally follow around the bumblebees as they foraged Briggs says.
It's challenging because the bees can fly pretty fast. Sometimes the researchers could only record between five and 10 movements
Running around after bumblebees in these beautiful wildflower meadows was one of the most fun parts of the research Brosi says.
so that researchers don't have a negative impact on the bumblebee populations. When we caught bees to remove target species from the system
Bumblebees are quite gentle on the whole. Across the steps of the pollination process from patterns of bumblebee visits to plants to picking up pollen to seed production the researchers saw a cascading effect of removing one bee species
. While about 78 percent of the bumblebees in the control groups were faithful to a single species of flower only 66 percent of the bumblebees in the manipulated groups showed such floral fidelity.
The reduced fidelity in manipulated plots meant that bees in the manipulated groups carried more different types of pollen on their bodies than those in the control groups.
when one of the bumblebee species was removed compared to the larkspurs in the control groups.
While previous research has shown how competition drives specialization within a species the bumblebee study is one of the first to link this mechanism back to the broader functioning of an ecosystem.
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