By: Fiona Smeaton
Pollinators are essential to the health and continuation of ecosystems across the planet. The keystone ecological services provided by pollinator species are irreplaceable and have allowed plants and animals, including humanity, to survive, grow, and thrive. We benefit from the fruits of their labor every time we leave the house or sit down for a meal, never realizing how tenuous our ecosystem might be. The conversion of pollinator habitat to human use, and resulting impact of habitat loss, is among the greatest threats to these industrious creatures. As the march of progress converts prairies and grasslands to agricultural use or other human development, invaluable pollinator populations are being forced to the brink by damage to or total loss of habitat. While there is a growing movement amongst farmers to keep pollinator-friendly acreage, the loss of habitat has greatly outpaced this movement, especially for native species. As our population, and therefore landscape, continues to trend towards increased urbanization it is important to understand how we can create and maintain healthy urban pollinator networks.
Most of us hear ‘pollinator’ and think of honeybees, bumblebees or hummingbirds. In reality there is an incredible diversity of creatures that pollinate the flowers we love in our garden. It is estimated that there are at least 500 species of native bees in the state of Oregon; however, data on this exact number is limited (Oregon Bee Atlas, 2018). In addition to bees there are flies, wasps, birds and even some mammals that pollinate. However, bees are the powerhouse pollinators! They are often the most effective as they will purposefully collect pollen and nectar from flowers and transport it so that fruits are formed. Most of the fruits and vegetables in our garden need bees. Next time you eat a fresh tomato, think of the fuzzy and powerful bumblebee that made it for you!
Unfortunately, native bees are declining at an alarming rate. Most of us have heard about Colony Collapse Disorder in honeybee colonies. However, much is still unknown about native bees. The problem is that there are combined impacts that are causing a more severe decline. The most serious risks are habitat loss and fragmentation, exposure to herbicides and insecticides, diseases, pathogens and climate change. With cities ever expanding and the draw on agriculture increasing there is less and less native habitat for bees to exist in. Many of these insect pollinators are adapting to living in the cities or on farms but they are faced with new sets of challenges from pesticides and diseases as they inhabit smaller spaces. Climate change is having an impact on native bees as well. It can cause offset bloom times where bees will emerge from their nests to see that the plant they previously depended on, has already bloomed or that it won’t bloom for some time to come.
As informed gardeners it is our responsibility to think critically about how we can support these native bees. We need them if we want to continue to see diversity in our gardens. If enough gardeners come together to devote even some of their space to pollinators, we can create a network of suitable environments that will enrich our gardens, our neighborhoods and our lives. Join us next week to learn about basic native bee identification and how to monitor them in your backyard!
I have always been passionate about connections between species in the natural world, I love to learn about organisms that have coevolved and formed mutually beneficial relationships. That is what first drew my attention to insect pollinators. I think that it is fascinating that these tiny creatures can play such a keystone role in an ecosystem. There would not be the incredible diversity of plants we know today without these insects. However, pollinators are currently facing a multitude of threats caused by humans' destructive practices on the modern landscape. Urban environments, while very disturbed and fragmented can provide valuable habitat for native pollinators. My Master’s program allowed me to investigate eight urban sites across Portland OR to find out which insect pollinators were observed in the summer of 2019 and which flowers they were visiting. My work was directed at urban land managers in Portland in order to help them strategize ways to create pollinator habitat around us. Now I want to share this information with the Cornell Farm community! This blog mini-series is meant to share my experiences monitoring insect pollinators and strategies I have learned in order to better understand how we can support these incredible species within our city.