Pollinators at Risk

Source: WikiCommons, credit Judy Gallagher

Without pollinators, most native plants would be unable to reproduce. Over 80% of all flowering plants worldwide reproduce with the help of animal pollinators. Wild bees are also among the most important pollinators of human food crops. Bumble bees have proven to be more effective pollinators than non-native honey bees for some food crops. And yet one-quarter of the bumble bee species once found in New York have already disappeared from the state. 

Your yard may appear to be buzzing with bees. It’s true that a small number of pollinators, such as the common eastern bumble bee (Bombus impatiens), are easy to spot in many backyards; and certain native pollinator populations are stable or even increasing. However, the overall diversity of pollinators has plummeted, and many Hudson Valley pollinator species are now on a steep decline. Newly released research from the Empire State Pollinator Survey found that between 38% and 60% of New York’s pollinators are now “at risk”—they are declining in number and at risk of extirpation. Extirpation means they will no longer be found in the state; they will be effectively extinct on a regional level. It’s estimated that over half of New York’s native pollinators are already extirpated. 

Pollination is the bedrock of our natural communities. The work of the Hudson Valley’s pollinators—which include bees, butterflies, moths, beetles, flies, and even bats and birds—is vital to the functioning of our natural systems. They help to fuel the food chain that nearly all animals rely on for sustenance and shelter, including human beings. Pollinators make our farms flourish and our forests function. However, the existence of many of our pollinators, and thus the integrity of our ecological communities, is under threat. 

The combined pressures of habitat loss, invasive species, and climate change have brought many species to the brink, and scientists are warning of a period of mass extinction.  Insect populations also face pressure from widespread pesticide use, now a cornerstone of landscaping and agriculture. Parasites and pathogens further stress these already fragile populations. In the Northeast, decades of extreme deer overpopulation have caused native plant populations to crash, resulting in severely diminished food and habitat resources for pollinators, even in wild areas. Globally, 40% of insects are believed to be at risk of extinction. 

Credit: Tina Bannon

This honeybee foraging on a native aster may do more harm than good. Photo: Adam T. Deen

The Hudson Valley’s pollinators are key players in our wild places, gardens, and farms - they are vital species on which the health of our ecologies and food system rests. 

Many factors contribute to pollinator decline, but changes in land use loom large among them. In the Hudson Valley, the proportion of developed land increased by over 25% from 2001 to 2019.

That means that more than 141,000 acres of fields and forest transformed into a landscape of primarily buildings, pavement, and turf, largely uninhabitable to pollinators. The Hudson Valley is not unique in this. In the lower 48 states, 54% of land has been developed for human uses such as cities, towns, roads, and shopping centers, and a further 41% is used for agriculture—totalling 95% of America that’s no longer wild and thus cannot support wildlife, including pollinators, as it once did.

These statistics are daunting, but this also means our collective future is in our own hands, since the majority of America’s lands are now privately owned. We can take real, meaningful action together, if we move strategically in the way we plant our yards, manage our hayfields, select trees and shrubs for hedgerows, and reclaim the fragile edges of our forests and waterways from invasive species and the impacts of deer overpopulation. Changes at all scales can make a difference - the massive acreage of our combined lawns alone holds immense potential for restoration, if we can reimagine even part of it as pollinator habitat.

A Pollinator’s Work 

Pollinators have an all-important job—they transport pollen from the male parts (stamen) of one flower to the female parts (stigma) of another, making plants’ sexual reproduction possible. Usually winged and agile, pollinators provide the critical transportation mechanism for their plant partners that remain rooted to the spot. In exchange for this service, pollinators collect their livelihoods—a meal of sugary nectar, or a share of the pollen, or both, to feed themselves and sometimes to provision their young. While some pollen is used to feed young bees or fuel pollinators’ flight, some of the pollen also rubs off along a pollinator’s travels. Pollen that lands on a flowers’ stigma travels down the style and fertilizes the egg-like ovules, beginning the development of seeds.

Occasionally, pollen may rub off on the stigma of a flower from the very same plant, resulting in self-pollination, and some flowers self-pollinate on purpose in case no pollinators are present. But generally, flowers stagger when their pollen and stigma are ripe and receptive, or have their male and female parts located at a distance from each other, even on separate flowers, or on separate, exclusively male and female plants, so that they can exchange pollen with other plants. This vital exchange of pollen, called cross-pollination, allows plant populations to reshuffle their genes, a crucial process that allows plants to evolve, adapt, and maintain healthy, resilient populations.

Why is it a problem if we lose a few pollinator species? 

The resilience of our ecological communities, especially in the face of climate change, depends on their biodiversity. Climate change is bringing a steady rise in temperatures to the Hudson Valley, as well as a dramatic increase in rainfall, heavy rainfall events and flash floods. Climate change also brings more frequent droughts, extreme weather events, and sea level rise, all of which create disturbances in nature—washing out riverbanks, inundating farms, taking down mature forest canopies. Research has consistently shown that the more diverse a community of plant and animal species, the better it can respond to challenges such as disturbance, stress, and disease. In a diverse community, there are multiple species to perform each role, such as predator, prey, pollinator, nectar source, or host plant. This ensures that there is always a substitute available to fill a gap when another species is lost or incapacitated.

Unfortunately, pollinator and plant diversity are both on the decline in the Hudson Valley and globally. The loss of plant species to human development has been substantial—approximately one quarter of New England’s plant species have already been lost. And some scientists estimate that if current trends continue, most insects will vanish by the end of this century, with impacts reverberating across food webs and human systems like agriculture. The time for action to reverse these trends is now. And we have the tools to increase pollinator diversity and resilience—by restoring the plants and landscapes on which they depend.

Small but mighty, each species contributes to the resilience of the whole ecological framework. Credit: Ashley Gamell

Honeybees: When Conservation Chooses the Wrong Poster Child

When the topic of pollinator conservation comes up, many people think foremost of honey bees, and the threats to honey bee populations that have been in the news. However, it’s important to recognize that unlike the native bumble bees, solitary bees, butterflies, moths, birds, flies, and beetles supported by this guide, honey bees are not native to this continent; they were brought to North America from Europe in the 1600s. They are now considered “naturalized” in North America—they have become so prevalent over such a long period of time that they have integrated into native natural communities. While not technically invasive, European honey bees have been linked to the decline in native bee populations. Though they can be valuable agricultural pollinators, honey bees have also been shown to compete with native bees for food resources in the wild, adding yet another stressor to native pollinator populations. While honey bees have their place in farm settings, they have not evolved to be effective pollinators for our native flora, can actually be harmful to our native ecology, and certainly distract attention from the native pollinators that should be the focus of our communal efforts and attention.

Here again, the resilience of our natural systems, including our food system, depends on their biodiversity. As honey bee populations on our farms become plagued by Colony Collapse Disorder and other afflictions, the value of diverse, healthy native bee populations becomes all the more clear. Current large-scale farming practices involve transporting huge hives of European honey bees from farm to farm, rather than managing farmlands to sustain local populations of native pollinators which can do the same job, and in some cases, do it better. As stressed-out honey bees accrue diseases, and accumulate a massive carbon footprint crossing state lines, the need to shift our focus to conserving native bees has never been more urgent. 

PLACE, PLANTS & POLLINATORS