As warmth returns to Wisconsin, urban residents emerge en masse from their cozy enclaves to retake the bike paths, urban parks, and lakeshore plazas that provide natural, common spaces for community activity. As the summer growing season takes off, prairie fragments sprout up around the city, cultivated in private yards, public parks, street terrace rain gardens, and storm water management areas. Prairie flowers color my vision of a Madison summer, along with the scent of milkweed and the click-clack of the sailboats on Lake Mendota. The Midwest prairie bloom is brought to life by the buzzing bees. Pollinators provide an important ecosystem service, assisting in the production of fruit as well as the reproduction of native plants, and contributing to the biodiversity of our urban flora.
Madison prides itself on its abundance of public gardens and parks, including conservation parks managed with priority for the non-human members of the urban community. The land management principles of the parks department have become more environmentally informed over time, alongside increasing environmental awareness among Madison residents. City parks are managed for many different purposes, however, so they do not maximize pollinator habitat and food resources. Improving pollinator habitat is a multifaceted goal in itself, as different pollinator “guilds” require different types of habitat and food resources. Species also differ in their time period of activity—while some remain active through the whole growing season, others are only out and about for a few weeks.
Scientists have found a great deal of evidence that a combination of factors from reduced nesting and food resources to parasite and pesticide impacts are causing widespread declines in pollinator populations. The Madison Pollinator Protection Task Force took on the goal of improving the urban environment for all bees, not just a single species, and in doing so they have provided a set of recommended actions for the city to undertake. Madison city employees are already preparing to implement some of these actions this approaching summer 2016.
Introducing the Bees
What do we mean by all bees, not just a single species? Bees are incredibly diverse in size and shape, and there are over 4,000 known species of bees in the United States, divided into six major families. There are two genera of eusocial bees that live in very organized colonies practicing cooperative brood care in North America. These are Apis (honey bees) and Bombus (bumble bees), both members of the Apidae family. There are no native honey bees in North America, and in fact, the only species is the European Honeybee (Apis mellifera), which is largely managed for agricultural pollination but also thrives in feral colonies. There are 46 species of bumble bees north of Mexico and about 15-20 of those species are found in Wisconsin. Unlike most other species of bees which prefer warm, dry climates, bumble bees are most abundant and diverse in cool mountainous landscapes. The rest of the 4,000 bee species in the United States are solitary bees, although many live in gregarious aggregations.
Sweat bees are members of the Halictidae family and most of them nest in the ground, excavating short tunnels in bare, loosely packed soil. Others nest in hollow branches or pithy stems, or rotting wood.
There are several species from the Andreninae subfamily, also known as Mining bees. These bees dig long branching tunnels in the ground, and many emerge early in the spring. Andrenid bees have patches of very short hair on their face, and they may or may not have long hair too.
Leafcutter Bees and Mason Bees
The Megachilidae family includes mason bees and leafcutter bees, among others. Most megachilids use small existing cavities to lay their eggs, sometimes in a mass of clay, wall, rock pile or plant stem. Leafcutter bees cut pieces of leaves to enclose their eggs in individual capsules.
Honey Bees and Bumble Bees
Honey bees and bumble bees are two genera from the family Apidae. These are the only two genera of social bees in North America, and both utilize cavities for their nest sites. Bumble bees frequently use abandoned rodent burrows, but they’ll also nest in human-made cavity spaces.
Carpenter bees are another common group of bees in the Apidae family. These bees tunnel into wood, and they range in size from very small to very large.
Pollinators have made the headlines frequently in past years, due to persistently high European Honey Bee losses. Studies show that many, but not all other native bee species, may also be on the decline. Because the European Honey Bee is the most common bee managed for large-scale agriculture, far more data is available to track their population dynamics. Wisconsin has been particularly hard-hit by high rates of honey bee colony losses in recent years, with more than 60% losses over the 2014-2015 winter, and a 19% decline in honey production in the year between 2013 and 2014 following several harsh winters.
Recent Political Action
In June 2014, President Obama issued a memorandum promoting the construction of a federal strategy to promote the health of honey bees and other pollinators. This White House communication instructed the formation of pollinator protection task forces in federal agencies, and many states have followed suit. The Wisconsin Pollinator Plan was recently completed by Christina Locke in the Gratton Lab at the University of Wisconsin-Madison, and other researchers. Here in Madison, Mayor Paul Soglin initiated the development of a city-wide pollinator protection plan as well. In October 2014, the Madison Food Policy Council was tasked with the formation of the Pollinator Protection Task Force by the Madison Common Council; interested community members such as Nathan Clarke of Mad Urban Bees and government staff such as Charlie Romines from Madison Parks, Roberta Sladky from Olbrich Gardens, and Mike Daley from Madison Engineering, joined the effort.
In some ways, Madison already stands out as a progressive, nature-friendly city with bee-keeping ordinances and relaxed zoning for community and market gardens. The city aims to minimize pesticide use in fulfillment of its mandate to uphold high standards of environmental health. However, pollinator habitat supplementation had not previously been a targeted goal of the city, so there is room to improve. The Madison Pollinator Protection Task Force outlined many great ideas to help our Madison pollinators, and they hope to begin implementation this summer.
Madison zoning ordinances allow urban bee keeping on private property, and during the formation of the Madison Pollinator Protection Task Force Report, published in 2015, ordinances for bee keeping allowance were expanded to include employment and airport districts. I spoke with Nathan Clarke, a prominent Madison apiarist (bee keeper/specialist), best-known in the city as the founder of Mad Urban Bees. Mr. Clarke explained how this ordinance provides necessary support to undertake urban beekeeping by defining specifically what is allowed by the city. Before the 2012 ordinance protecting urban bee keeping under specific guidelines, complaints could endanger precious investments by urban apiarists if bees were viewed as a nuisance.
Nathan Clarke’s business, Mad Urban Bees, offers bee keeping classes and distributes 90 of its own honey bee hives across the cities of Madison, Middleton, and Monona. The company provides 5-frame nucleus hives that are hosted in private backyards and rooftops all across our urban landscape, including the hives you may have noticed at Olbrich Gardens. Mr. Clarke has noticed that urban areas have longer growing seasons than surrounding agricultural land, and support a plethora of flowering trees and ornamental plants that provide diverse flavors of local honey. The Madison folks who host Mad Bee hives pay a fee in exchange for hive maintenance and delicious honey. Honey is harvested in microbatches to preserve the diversity of flavors and colors as different floral species fluctuate in availability through the season. Mr. Clarke listed basswood, dandelions, creeping charlie, bergamot, sedum, mint, and oregano as some of the bee’s identifiable favorite food sources.
Nathan Clarke’s role in urban pollinator protection stretches beyond his leadership of a successful local bee keeping business—Mad Urban Bees took 60 new applications for their ten openings this year! Mr. Clarke is a member of the Madison Food Policy Council, so as the Pollinator Protection Task Force formed in 2014, he was an enthusiastic addition with important practical experience, and he continues to participate as a member of the implementation committee. This important work is good for business as well as biodiversity and conservation of native bees-sustaining our local food economy and ecosystem functions alike.
The City of Madison Building Inspection Division inspects public and private land management practices across the city to enforce compliance with Madison General Ordinances, including lawn maintenance. These ordinances require that urban lawn areas are not to exceed eight inches, unless species and buffer support the approval of the site as a “natural lawn.” Currently, city policy is to not regulate gardens on private property that violate this ordinance; however, inspection staff would like to see the development of a regulatory framework that defines gardens more specifically, to protect urban gardens within limitations.
Storm Water Management Land
Storm water management lands are spaces set aside by the city to help manage the hydrological cycling of water through the urban landscape. Many of these areas grow into lush prairie blooms through the summer months and, from personal experience, these locations support a surprisingly diverse bee community during that period. However, current mowing practices may cause unnecessary disturbance to resident ecological communities.
Most of the city’s storm water management areas were planted with turf decades ago under management of the city’s Parks Division. As these land holdings were transferred to the Madison Engineering Division in 2000, they were replanted with native prairie grasses and other prairie plants with deep roots to improve water penetration. Without much restoration management, many of these sites have sustained a great deal of biodiversity loss, although some Madison residents have helped to mitigate this. In 2012, a Madison resident and prairie restoration advocate, Si Widstrand, provided a useful critique of mowing practices that negatively affect city prairie fragments. Most of these urban properties maintained by the Storm Water Utility are now only mowed once or twice a year, and these events are now planned at the end of the year as often as possible.
This summer, Madison Engineering plans to adjust mowing practices to promote new spot-mowing techniques to optimize management that promotes healthier grassland communities. This management is designed to prevent the need for more frequent or intrusive mowing regimes. The Storm Water Utility owns 1,417 acres of land, including most of the city’s wetlands and floodplains. The Engineering Division also owns and maintains about 82 acres of closed landfills mainly as prairie land and a number of street terrace rain gardens.
Environmental Education and Diversity Hotspots
The University of Wisconsin Arboretum and Madison’s Olbrich Botanical Gardens have long served as environmental education centers that exhibit a grand abundance of plant and pollinator biodiversity within our urban landscape. Both sites have observed rusty patch bumble bees, a Bombus species thought to be extirpated from this part of its range. Olbrich gardens hosted a field trip for the Madison Pollinator Protection Task Force, as they worked towards their published set of policy recommendations last year. The Arboretum displays pollinator identification guides and images, and regularly surveys bumble bee diversity in their prairie. This past summer, the arboretum hosted a Pollinator Education Community Event, lead by Christina Locke, the lead author of our recently released Wisconsin Pollinator Plan.
Featured Image: UW-Madison Arboretum, Vera Pfeiffer, summer 2015.
Vera Pfeiffer is an Environment and Resources PhD student in the Nelson Institute for Environmental Studies at University of Wisconsin-Madison. Her research focuses on land use effects on bee assemblage and activity. She utilizes diverse methods including trapping, modeling, pollen analysis, and landscape genetics to learn more about pollinators and urban and agricultural landscapes. Recently, she investigated Madison’s urban pollinators first-hand, trapping bees at private residences, businesses, and city properties. Contact. Website.