Honeybees hog the limelight, yet wild insects are the most important and vulnerable pollinators



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Szefei / http://www.shutterstock.com

Philip Donkersley, Lancaster University

Pollinating insects like bees, butterflies and flies have had a rough time of late. A broad library of evidence suggests there has been a widespread decline in their abundance and diversity since the 1950s. This matters because such insects are critical both for the reproduction of wild plants and for agricultural food production.

The decline of these pollinators is linked with destruction of natural habitats like forests and meadows, the spread of pests such as Varroa mite and diseases like foulbrood, and the increasing use of agrochemicals by farmers. Although there have been well documented declines in managed honeybees, non-Apis (non-honeybee) pollinators such as bumblebees and solitary bees have also become endangered.

There are more than 800 wild (non-honey) bee species in Europe alone. Seven are classified by the IUCN Redlist as critically endangered, 46 are endangered, 24 are vulnerable and 101 are near threatened. Collectively, losing such species would have a significant impact on global pollination.

Though much of the media focus is on honeybees, they are responsible for only a third of the crop pollination in Britain and a very small proportion of wild plant pollination. A range of other insects including butterflies, bumblebees and small flies make up for this pollination deficit.

Butterfly pollinating during monsoon season.
Hitesh Chhetri / http://www.shutterstock.com

Not all pollinators are created equal

Pollinators also vary in their effectiveness due to their behaviour around flowers and their capacity to hold pollen. Bigger and hairier insects can carry more pollen, while those that groom themselves less tend to be able to transfer pollen more effectively. Bumblebees, for example, make excellent pollinators (far superior to honeybees) as they are big, hairy and do not groom themselves as often.

Where they are in decline, honeybees suffer primarily from pests and diseases, a consequence of poor nutrition and artificially high population density. This differs from other pollinators, where the decline is mainly down to habitat destruction. It seems pesticides affect all pollinators.

An ashy mining-bee (Andrena cineraria) settles in for a snack.
Philip Donkersley, Author provided

Save (all) the bees

Curiously, the issues facing non-Apis pollinators may be exacerbated by commercial beekeeping, and attempts to help honeybees may even harm efforts to conserve wild pollinators.

The problem is that there are only so many flowers and places to nest. And once the numbers of honeybees have been artificially inflated (commercial-scale beekeeping wouldn’t exist without humans) the increased competition for these resources can push native non-Apis pollinators out of their natural habitats. Honeybees also spread exotic plants and transmit pathogens, both of which have been shown to harm other pollinators.

The European honey bee (Apis mellifera) is the most common species of honey bee.
Philip Donkersley, Author provided

Over the coming decades, farmers and those who regulate them are faced with a tough challenge. Agricultural output must be increased to feed a growing human population, but simultaneously the environmental impact must be reduced.

The agriculture sector has tried to address the need to feed a growing population through conventional farming practices such as mechanisation, larger fields or the use of pesticides and fertiliser. Yet these have contributed to widespread destruction of natural landscapes and loss of natural capital.

Limited resources and land use pressure require conservation strategies to become more efficient, producing greater outcomes from increasingly limited input.

A mosaic of different flowers: these sorts of landscapes are paradise for bees.
Philip Donkersley, Author provided

Cooperative conservation

So-called agri-environment schemes represent the best way to help insect pollinators. That means diversifying crops, avoiding an ecologically-fragile monoculture and ensuring that the insects can jump between different food sources. It also means protecting natural habitats and establishing ecological focus areas such as wildflower strips, while limiting the use of pesticides and fertilisers.

As pollinating insects need a surprisingly large area of land to forage, linking up restored habitats on a larger scale provides far more evident and immediate benefits. However, so far, connections between protected areas have not been a priority, leading to inefficient conservation.

The ConversationWe need a substantial shift in how we think about pollinators. Encouraging land managers to work cooperatively will help create bigger, more impactful areas to support pollinators. In future, conservation efforts will need to address declines in all pollinators by developing landscapes to support pollinator communities and not just honeybees.

Philip Donkersley, Senior Research Associate in Entomology, Lancaster University

This article was originally published on The Conversation. Read the original article.

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Delaying action on car emissions will make Australia more vulnerable


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We don’t know what the car of the future will look like – but that’s no excuse to delay transport reform.
www.twin-loc.fr/Flickr, CC BY-SA

Bonnie McBain, University of Newcastle

France has set its car manufacturers the goal of halting sales of diesel and petrol cars by 2040. The announcement last week came a day after the Swedish manufacturer Volvo declared it will build only hybrid and electric cars from 2019.

Moving away from highly polluting cars is an urgent global priority. Worldwide, transport accounts for 26% of humanity’s carbon dioxide emissions and, of these emissions, 81% comes from road transport.

Our latest research, published in the International Journal of Sustainable Transportation, shows that car ownership and the total distance travelled by cars are both likely to keep growing, globally and in Australia.

But just because there will be more cars, covering more ground, that doesn’t necessarily mean CO₂ emissions will continue to rise. It depends on a complex mix of population trends, income growth and the impacts of new policies and technologies.

It might therefore seem sensible to delay policy decisions until we can see what type of future emerges. However, our research found that a “wait and see” approach will dramatically increase our economic, social and environmental vulnerability.

Lower-income Australians are particularly at risk. This is because transport accounts for a greater proportion of their household income and they tend to live on the urban fringe where daily travel distances are necessarily higher.

Future-proofing our transport policy means we must engage with uncertainty, not ignore it. That means choosing policies that allow us to adapt to a range of technological or social developments.

We modelled different policy options in Western Australia, looking for options that reduced CO₂ emissions without creating social vulnerabilities. The most effective approach requires simultaneously improving fuel standards, making cars more efficient, and increasing city density to reduce both car ownership and the total distance we need to travel in cars.

However, CO₂ emissions alone don’t provide the full picture. Our model found that encouraging biofuels, for example, could mean increasing our agricultural footprint to grow feedstock.

Similarly, electric and hydrogen-fuelled vehicles require energy supplied by the electricity sector. As this sector itself decarbonises, technologies such as solar, hydro and wind will require greater areas of land than coal and gas technologies.

However, managing carbon dioxide emissions and demand on land is not necessarily mutually exclusive. Wind turbines can co-exist with grazing, and decentralised solar panels are already common on existing buildings. Offshore wind farms and solar installed on otherwise unproductive land can lessen impact. Targeted investment in technological efficiency can further reduce this impact.

Using land for both agriculture and energy production could actually give farmers greater economic resilience. Alternative fuels that use waste products or are low-impact (such as biofuel made from algae) are also promising avenues.

The economic case for expensive changes

Although the implementation of stringent transport policy will be costly – it requires massive changes in capital infrastructure and behaviour – it will open up other benefits and saving.

Vehicle emissions are recognised as the source of more air pollution than any other single human activity. These emissions cause hundreds of preventable deaths in Australia every year. (As well as saving lives, we’d also save billions of dollars in related costs.)

Well-designed, more compact urban spaces encourage more biking and walking. This, in turn, reduces chronic diseases that also cost Australians billions every year.


J G/Flickr, CC BY-NC

Research shows that compact cities reduce infrastructure costs by 11%; a 2015 report found gridlock alone could cost Australia A$53 billion by 2031. Curbing urban sprawl can reduce the clearing of native vegetation, which benefits the rivers and animals that live around our cities.

Changing the type of fuel used by cars, improving vehicle efficiency and increasing city density are all policy levers that can reduce the footprint of urban cars, but these must occur in tandem. To minimise costs and realise the potential savings, policymakers need to collaborate on finding policies that are flexible enough to adapt to an uncertain future.

The ConversationShould we have the leadership to implement such sophisticated policy, we might accidentally design a future in which we are healthier and happier too.

Bonnie McBain, Tutor in Sustainability Science, University of Newcastle

This article was originally published on The Conversation. Read the original article.

Chile: Bottom Trawling Banned in Vulnerable Marine Ecosystems


The link below is to an article that reports on Chile’s banning of bottom trawling in all vulnerable marine ecosystems.

For more visit:
http://newswatch.nationalgeographic.com/2013/01/14/chile-becomes-first-country-to-protect-all-seamounts-from-bottom-trawling/