“Agricultural resiliency comes from having stability in our pollinator populations,” says Dr. Sargent. “Challenges like climate change, for example, clearly cause unpredictability for food producers—by diversifying our agro-ecosystems we will increase their resiliency, ensuring a sustainable food system in a rapidly changing world.”
Climate change isn’t the only threat to agriculture, of course. Dr. Sargent’s PPGC research team starts from a necessarily broad understanding of resiliency that focuses on the major threats to pollinators, ranging from habitat loss to the arrival of invasive species. At the same time as seeking to understand the nature of these stresses, the lab also aims to discover potential solutions.
"If we want secure, environmentally friendly diversified food systems, farmers need to be supported financially and government, researchers and agriculture need to work together much more effectively.”
- Dr. Risa Sargent
One recent project from PPGC doctoral student Jens Ulrich scrutinized the value of urban pollinator initiatives. These programs have been trialed in cities including Vancouver where several public parks were recently seeded with insect-friendly meadows. Ulrich’s study revealed that while the plants typically grown in these plots did not noticeably increase the diversity of pollinating insects, the native plants near the meadows—such as salmonberry and Oregon grape—were excellent attractors for a broad array of beneficial insects.
Reflecting the crucial importance of insects, the PPGC team isn’t the only LFS lab focusing on their vital roles. Spearheaded by Associate Professor Juli Carrillo, the Plant-Insect Ecology and Evolution Lab (PIEE) takes an ecological theory approach to investigating the value of insect biodiversity—in particular, the insect communities that live alongside agricultural ecosystems.
In one recent PIEE project, researcher Matt Tsuruda looked at how increased agricultural intensification and a resulting reduction in natural habitats can drive declines in local beneficial insect diversity. Tsuruda showed that by restoring habitats such as hedgerows and grasslands near agricultural fields we can support a larger and more diverse population of beneficial insects—including those that help keep pest populations at bay.
Working to understand the conditions insects actually need in order to thrive shapes much of the research conducted by Dr. Sargent, Dr. Carrillo and their teams. But one of the challenges, says Dr. Sargent, has been that much of the available deep-level data on insects often has critical gaps. “Over the years, people have been less likely to collect data on insects generally so although there are museum collections and citizen science records, we don’t have a lot of high quality, longitudinal survey data to draw on.”
Despite this, she adds, many of the biggest stresses on pollinator populations are well known. These include the use of newer pesticides in agriculture that can cause insect death or behavioural changes that impact pollinator health. The effects of these challenges are not shared equally across all species, she notes, suggesting that maximizing biodiversity can help mitigate the impact of declines. “Some wild bees are clearly in decline while others are doing better,” says Dr. Sargent. “It’s not clear whether all pollinator populations are declining—I would describe it as a fuzzy picture with lots of concern.”
In spite of the knowledge gaps, there is much that agriculture can do to support the wild pollinator populations it relies on. But, adds Dr. Sargent, we need to do more to encourage and help farmers to add the kind of amenable habitats to their properties that encourage beneficial insect diversity.
Clearly, she adds, the time for new approaches is now. “In B.C., we’re just starting to recognize that climate changes and other environmental challenges are not temporary and that we need to address these issues urgently. But I’m an optimist at heart and there are lots of reasons for hope. The natural world is a wealth of inspiration and my students’ commitment to studying and conserving biodiversity brings me much hope for the future.”