butterflies

Examining The Decline Of Honey Bees | Earth Wise

December 28, 2022 By EarthWise Leave a Comment

For many years, scientists have been sounding the alarm on the global struggle of pollinators. Many of the invertebrate pollinator species, such as bees and butterflies, are facing extinction. And since 75% of the world’s food crops depend on pollination to some extent, the decline of pollinators poses a major threat to global food security.

Honey bees are among the struggling pollinators. Over the past 14 years, bee colonies have been disappearing at an alarming rate in what is known as the “colony collapse disorder.”

In an effort to understand why, scientists have often focused their research on environmental stressors, such as parasites, pesticides, and disease. But according to new research by entomologists from the University of Maryland, honey bee life spans are simply 50% shorter today than they were 50 years ago. In the study, which was recently published in the journal Scientific Reports, the researchers found that honey bees kept in a controlled, laboratory environment lived half as long as honey bees did in the 1970s. This is the first study to show that genetics – as opposed to environmental stressors – may be influencing the broader trends seen in the beekeeping industry.

When the researchers modeled the effect of their findings on a beekeeping operation, they found that the resulting loss rates were about 33%. This is similar to the average overwinter and annual loss rates reported by beekeepers during the past 14 years.

The next step is for researchers to compare trends in honey bee life spans across the U.S. and in other countries to see if there are differences in bee longevity.

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Honey Bee Lifespans are 50% Shorter Today Than They Were 50 Years Ago

Helping Agriculture’s Helpful Honey Bees

Photo, posted June 23, 2007, courtesy of Susan E. Ellis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Some Good Monarch News | Earth Wise

July 8, 2022 By EarthWise Leave a Comment

Eastern monarch butterflies spend their winter months in central Mexico. Every spring, they embark on a lengthy, multigenerational migration that takes them into the United States and even into southern Canada, where they breed. The butterflies go through several generations before they eventually migrate back to Mexico.

Twenty-five years ago, overwintering monarchs in Mexico blanketed nearly 45 acres of forest. The acreage covered, which has been surveyed annually since 1993, is a rough indicator for the actual number of butterflies that survive the difficult migration process. In 2013, the monarchs occupied only 1.6 acres of Mexican forest. The butterflies were deemed to be on the edge of extinction.

Last December, the monarch survey found 7 acres covered by the butterflies, an increase of 35% over the previous winter. The population appears to be steadily rebounding, although the numbers are still substantially lower than the levels seen in the 1990s.

The butterflies are struggling with multiple problems. There continues to be a lack of milkweed, the only food source for the caterpillars, in their breeding grounds along their migratory route. More extreme weather driven by climate change is another challenge, and illegal logging in their overwintering habitat in Mexico has also become a threat.

After the butterfly population crashed in 2013, conservation efforts shifted into high gear with lots of milkweed planting in the US and Canada, and crackdowns on timber poachers in Mexico.

The remarkable multigenerational migration of monarchs is a delicate phenomenon that can be disrupted by many different things. Eastern monarchs are still in serious danger, but the current trend seems to be positive.

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Warming Trends: Butterflies Bounce Back, Growing Up Gay Amid High Plains Oil, Art Focuses on Plastic Production

Photo, posted August 12, 2021, courtesy of Paul VanDerWerf via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Plight Of Monarch Butterflies | Earth Wise

April 20, 2022 By EarthWise Leave a Comment

The monarch butterfly is one of the world’s best-known butterflies and has become the symbol for a whole class of imperiled pollinators. Populations of the iconic orange-and-black insects have declined dramatically in recent decades.

According to the U.S. Fish and Wildlife Service, the eastern monarch population has dropped 88% between 1996 and 2020. Habitat loss, pesticide use, and global climate change are some of the factors driving monarch butterfly population declines.

According to a new study led by scientists at Emory University, monarch butterflies are also increasingly plagued by a debilitating parasite. The study, which was recently published in The Journal of Animal Ecology, reviewed 50 years of data on the infection rate of wild monarch butterflies by the protozoan Ophryocystis elektrosirrha (or O.E.). The research team found that the O.E. infection rate had increased from less than 1% of the eastern monarch population in 1968 to as much as 10% today.

The O.E. parasite invades the gut of monarch caterpillars. If the adult butterfly leaves the pupal stage with a severe parasitic infection, it begins oozing fluids from its body and dies. If the infection is lighter and the butterfly survives, it will not fly as well or live as long as uninfected butterflies.

The study found that one of the contributors to the rise in parasitism is the increased density of monarchs in places where they lay their eggs. The increased density may be due to several factors, including the loss of habitat, the widespread planting of non-native milkweed, and by people raising large numbers of monarchs in confined spaces.

If the infection rate continues to increase, monarch butterfly populations will likely continue to plummet.

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Monarch butterflies increasingly plagued by parasites

Plight of the Monarch

Saving The Monarch Butterfly

Photo, posted September 18, 2008, courtesy of Roy Niswanger via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Butterflies And Moths In A Changing World | Earth Wise

July 20, 2021 By EarthWise Leave a Comment

Extinction is a part of life. Plant and animal species disappear all the time. In fact, approximately 98% of all the organisms that have ever existed on planet earth are now extinct. Earth’s so-called ‘normal’ rate of extinction is thought to be somewhere between 0.1 and 1 species per 10,000 species per 100 years.

But anthropogenic climate change is bringing about rapid change in nature. Put more simply, human activity is killing nature at an unprecedented rate. According to many scientists, the earth’s sixth mass extinction has already begun. Mass extinctions are defined as times when the Earth loses more than 75% of its species in a geologically short interval.

The changing climate puts immense pressure on species for change. According to a new study by researchers from the University of Helsinki and the Finnish Environment Institute, the few butterfly and moth species capable of adjusting to the changing climate by moving up their flight period and moving further north have fared the best.

In Finland, researchers compared temporal shifts in the flight period and spatial shifts in the northern range boundary of 289 moth and butterfly species, as well as changes in abundance over a roughly 20-year period.

They found that about 45% of species that either moved northward or advanced their flight period fared much better than the roughly 40% of species that did not respond in either way. On average, the populations of these poorly responding species declined. But the 15% of species that did both had the largest increase in abundance.

The ability to adapt to a changing climate is going to be vital for species survival.

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Butterflies and moths have difficulty adjusting to a rapidly changing climate

What is mass extinction and are we facing a sixth one?

Photo, posted August 16, 2017, courtesy of Tero Laakso via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Residential Gardens And Pollinators | Earth Wise

April 2, 2021 By EarthWise Leave a Comment

A new study led by the University of Bristol in the UK measured for the first time how much nectar is produced in urban areas to gauge the role of residential gardens in providing nutrients for pollinators. They discovered that home gardens accounted for the vast majority of the crucial nutrients for pollinators; in fact, some 85% on average.

The study found that gardens generated a daily average of about a teaspoon of the unique sugar-rich liquid found in flowers which pollinators drink for energy. A teaspoon sounds like very little, but it is enough to feed thousands of bees.

The research examined nectar production in four major UK towns and cities and measured nectar production in nearly 200 species of plants. The results were that the nectar supply in urban landscapes is more diverse than in farmland and nature reserves. In addition, gardens are critical because they produce the most nectar per unit area of land and actually cover the largest area of land in the cities studied. In those cities, nearly a third of the land comprised domestic gardens, which is six times the area of parks and 40 times the area of small green allotments.

The upshot of the research is that home gardeners have a huge role to play in pollinator conservation. Without domestic gardens, there would be far less food for pollinators that include bees, wasps, butterflies, moths, flies, and beetles. Thus, it is important for home gardeners to keep planting nectar-rich flowers, mow lawns less often to let dandelions, clovers, and daisies flourish, avoid harmful pesticides, and avoid covering gardens in paving, decking, or artificial turf.

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Pioneering research reveals gardens are secret powerhouse for pollinators

Photo, posted June 23, 2018, courtesy of Wolfferl via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Non-Native Plants And Insect Decline | Earth Wise

January 15, 2021 By EarthWise Leave a Comment

Global insect populations have been in decline since the beginning of the 20th century. The decline accelerated during the 1950s and 1960s, and it has reached alarming levels during the past 20 years.

The causes of plummeting insect populations include habitat destruction, deforestation, climate change, light pollution, and the rise of industrial agriculture. This so-called insect apocalypse is being mirrored by a bird Armageddon because so many bird species depend on insects for their diets.

A still controversial, but increasingly likely factor in the decline of insect populations is the spread of non-native plants in agriculture, agroforestry, and horticulture. A recent study published in the journal Ecological Entomology presents recent data supporting the proposition that the widespread displacement of native plants is a key cause of insect declines.

Many insects depend on a limited number of plants for survival. In many cases, insects’ diets are restricted to a single plant family. When native host plants dwindle or disappear from an area, the population of insects that depend on those plants shrinks.

There are examples of insects that adopt introduced plants as food sources, such as silver-spotted skipper butterfly larvae feeding on invasive kudzu in the eastern U.S. But generally, the widespread incursion of non-native plants is harmful to native insect populations.

Non-native plants are especially popular for horticulture. Millions of acres of potential insect habitat have been transformed into food deserts for native insects. The authors of the recent study recommend that Americans should extensively include native plants in their yards to help preserve insect diversity.

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How Non-Native Plants Are Contributing to a Global Insect Decline

Photo, posted May 2, 2004, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Decline Of Pollinators Threatens Food Security | Earth Wise

August 24, 2020 By EarthWise Leave a Comment

Scientists have been sounding the alarm on the global struggle of pollinators for many years. According to a United Nations-sponsored report, 40% of invertebrate pollinator species, including bees and butterflies, are facing extinction. Approximately 80% of all flowering plant species, which are responsible for 35% of global food production, depend on pollination.

According to new research led by Rutgers University, crop yields for apples, blueberries, and cherries in the United States are being reduced by a lack of pollinators. The study, the most comprehensive of its kind to date, found that crop production would be increased if crop flowers received more pollination. In the U.S., the production of crops that depend on pollinators generates more than $50 billion a year.

For the study, which was recently published in the journal Proceedings of the Royal Society B, researchers collected data on insect pollination of crop flowers and yield of apples, highbush blueberries, sweet cherries, tart cherries, almonds, watermelons, and pumpkins at 131 farms across the United States and British Columbia, Canada. Four of those seven crops – apples, blueberries, sweet cherries, and tart cherries – showed evidence of being limited by pollination, meaning that their yields are lower than they would be with full pollination.

The researchers observed that honey bees and wild bees provided similar amounts of overall pollination, so managing habitat for native bee species or stocking more honey bees would boost pollination levels and, in turn, crop production.

Bees and other pollinators play a critical role in food production, and their continued decline could have devastating consequences.

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Decline of bees, other pollinators threatens US crop yields

Photo, posted April 22, 2012, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Trouble For Monarchs | Earth Wise

April 14, 2020 By EarthWise Leave a Comment

Monarch butterflies have been in trouble for quite a while and now it seems like their prospects are worse than ever. Multiple surveys of butterfly populations are reporting plummeting numbers.

Western monarch butterflies spend their winters on the central California coast. Months later, they breed in California’s Central Valley and as far north and east as Idaho. But in recent years, it has become harder and harder to find them in their breeding sites.

The Western monarch population was in the millions in the 1980s. In 2017, an annual survey found 200,000 butterflies. In 2018 and 2019, only about 30,000 butterflies were tallied. The loss of Western butterflies in general has come about from a variety of factors, including development, climate change, farming practices and the widespread use of pesticides by farmers and on home and business lawns.

Scientists use the area of land that migrating Monarchs occupy in Mexico to gauge populations. This year, they covered about 7 acres, down from 15 acres in 2019.

Meanwhile, there are also far fewer Eastern monarch butterflies on the opposite side of the country. According to a new population survey, the Eastern monarch has passed the extinction threshold. Its population in 2020 dropped 53% from its already low 2019 numbers. Scientists were expecting lower numbers this year, but they were staggered by their findings.

Butterfly populations are quite variable, so it is possible that the drastic declines this year are not necessarily irreversible, but the news is not good. Researchers and environmental advocates continue to point out that mitigating the climate crisis, reducing pesticide use and planting pollinator gardens could help the butterflies to recover.

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Monarch Butterfly Populations Are Plummeting

Photo, posted September 7, 2017, courtesy of C. Watts via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Falling Bee Populations

September 9, 2019 By EarthWise Leave a Comment

For many years, scientists have been sounding the alarm on the global struggle of pollinators. A reported 40% of invertebrate pollinator species, including bees and butterflies, are facing extinction. And since as much as three-quarters of the world’s food crops depend on pollination, the decline of these pollinators poses a major threat to global food security.

Pollinators aid in the production of all sorts of crops, including coffee, cacao, cotton, apples, and almonds – to name a few. The global value of crops requiring pollination ranges from $235-$577 billion annually.

Honey bees are among the struggling pollinators. Over the past 15 years, bee colonies have been disappearing at an alarming rate in what is known as the “colony collapse disorder.” Some regions have seen losses of up to 90%.

In the United States, managed honey bee populations declined by nearly 40% over this past winter, the largest such winter decline since surveying began in 2006.

In recent months, mass honey bee declines have also been reported in Russia, according to the BBC. Russia, which produces a whopping 110,000 tons of honey annually, expects that figure to drop by as much as 20%. The widespread bee decline is likely to not only push up honey prices, but the prices of other popular foods as well. Many staple food crops in Russia, including sunflowers, buckwheat, and fruit trees, rely on bees for pollination.

Experts have blamed the bee decline crisis on a combination of factors, including pesticides (most notably neonicotinoids), varroa mites, and climate change.

Bees play a vital role in food production, and their continued decline will have devastating consequences.

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Russia alarmed by large fall in bee populations

Photo, posted July 28, 2019, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cities And Monarch Butterflies

August 13, 2019 By EarthWise Leave a Comment

Monarchs are some of the most well-known butterflies in the U.S. It is well-known that populations of the iconic orange-and-black butterflies have been in a steep decline for the last 20 years. In fact, the Monarch population has declined by 80% over that period.

Milkweed, the only plant that Monarchs can lay their eggs on, continues to disappear across the United States and with it, the butterflies can disappear too.

Two new studies published in the journal Frontiers of Ecology and Evolution show that one of the most important things that can be done to save the Monarchs is to plant milkweed in cities.

We tend to think of cities as being the enemy of nature. But metropolitan areas actually matter for wildlife conservation and that is especially true for pollinators like butterflies that can actually survive with very small patches of habitat.

The new study estimates the amount of habitat in cities that is available to Monarchs and other pollinators and how much more can potentially be added. It looked at cities from the Monarch’s point of view by identifying the best places and most effective ways to engage land owners to transform low-quality green space – such as lawns – into high-quality homes for butterflies and other wildlife.

Just because urban dwellers can plant milkweed doesn’t always mean that they will. There has to be a public perception that milkweed and other native flowers are acceptable and beautiful elements in home landscaping. It will require some shifting of societal norms of what is desirable in neighborhood gardens in order for cities to be able to do their part in protecting butterflies and other species struggling in the modern world.

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Cities are Key to Saving Monarch Butterflies

Photo, posted August 31, 2012, courtesy of Chris via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bee Friendly Amsterdam

February 11, 2019 By EarthWise Leave a Comment

Scientists around the world have been sounding the alarm for years about the decline of bees and other pollinators that are crucial to the growth of crops. One place where this trend has been bucked is in Amsterdam. The diversity of wild bee and honeybee species in the Dutch capital has actually increased by 45% since 2000.

The city attributes this success to creating bee-friendly environments including the installation of so-called insect hotels. There has also been a ban on the use of chemical pesticides on public land.

Four years ago, Amsterdam set a goal to convert half of all public green spaces to native plants including species that produce flowers and fruits that provide nourishment for bees. Developers in Amsterdam are encouraged to install green roofs on new buildings which reduce reliance on heating and cooling systems and also create habitat for wildlife.

Residents can request to have a 16-inch strip of pavement adjacent to their homes removed in order to plant shrubs, flowers or climbing vines. When a new highway was built in the area in 2015, local activists planted wildflowers along the sides of the road that otherwise would have been left with only gravel or grass. This practice has spread to other major routes and along dikes and railways and is referred to as the Honey Highway.

All of these efforts seem to be having a positive effect. An initial survey was conducted in 2000 to establish a baseline. A 2015 survey of pollinators found 21 bee species not previously documented in the city. The rest of the Netherlands has not done as well, and the Dutch government has recently introduced a pollinator strategy to revive bees, butterflies and other insects crucial to the country’s food crop.

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Bees are dying at an alarming rate. Amsterdam may have the answer.

Photo, posted December 28, 2006, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Pollinators With Backbones

May 25, 2018 By EarthWise Leave a Comment

There is a great deal of concern about the status of pollinators like bees and butterflies. They play a crucial role for many important food crops. But it turns out that lizards, mice, bats and other vertebrates are important pollinators too.

Help Save The Bees

December 13, 2016 By EarthWise

Globally, 40% of invertebrate pollinator species, such as bees and butterflies, are facing extinction. And since approximately three-quarters of the world’s food crops depend on pollination, the decline of these pollinators could pose a threat to food security around the globe.

[Read more…] about Help Save The Bees

Endangered Bees

October 27, 2016 By WAMC WEB

It’s no secret that pollinators around the world are under threat. According to a U.N. sponsored report released earlier this year, 40% of invertebrate pollinator species, such as bees and butterflies, are facing extinction. And since approximately 75% of the world’s food crops depend on pollination, the decline of these pollinators poses a major threat to food worldwide.

[Read more…] about Endangered Bees