From potential to practical: conserving bees in urban public green spaces

Abstract

The documentation of many rare or declining bee species in urban green spaces has led to a recent focus on cities as conservation targets. However, for pollinator conservation to succeed long term, we argue that the opinions and values of local community members must be prioritized more explicitly. In our experience, conservation is difficult to achieve when the aesthetic and safety concerns of urban residents are not reconciled with the goals and habitat designs of conservation practitioners. Similarly, from a bee ecology perspective, many questions concerning optimal design and management practices for pollinator habitats in cities remain unresolved. It is our hope that frank discussion of the challenges associated with urban pollinator conservation in public green spaces will inspire thoughtful consideration of how best to implement new initiatives in cities.

Beyond the Decline of Wild Bees: Optimizing Conservation Measures and Bringing Together the Actors

“…In order to reach these goals, a range of strategies targeting the protection and restoration of ecosystems, the enhancement of biodiversity, the decrease of invasive alien species or the communication about diversity loss have been adopted from global (e.g., The World Bee Project which aims to combine cloud computing with bee research across the world to provide to all new insights and knowledge in order to find solutions to the global bee and biodiversity decline, climate change and increase food security and livelihoods) to continental scale with, among others, strategies undertaken by the European Union (i.e., EU Biodiversity Strategy to 2020, [82]) addressed to be then applied and adapted at national scale e.g., [83] as well as at different levels to counter or mitigate the decline of pollinators (e.g., in USA, [84]; in France, [85]; in Ireland, [86]). Non-governmental (e.g., Seeds for Bees, Bee and Butterfly Habitat Fund) as well as Governmental programs (e.g., The Dutch Bee Strategy, the English National Pollinator Strategy) have help to gather stakeholders from various backgrounds to share their expertise and act jointly [87,88]. To perpetuate these initiatives, the implication of public audience, notably through citizen sciences and the participation of youth is essential [88].…”

“…Non-governmental (e.g., Seeds for Bees, Bee and Butterfly Habitat Fund) as well as Governmental programs (e.g., The Dutch Bee Strategy, the English National Pollinator Strategy) have help to gather stakeholders from various backgrounds to share their expertise and act jointly [87,88]. To perpetuate these initiatives, the implication of public audience, notably through citizen sciences and the participation of youth is essential [88]. In the following sections, we detailed the management measures that can be conducted from protected areas, to more anthropogenic landscapes.…”

“…Yet, a shift in floral resources occurred during the last decades is among the most common stressor affecting wild bee habitats and could lead to floral resources depletion as well as changes in plant-pollinator networks [50,144]. The choice of plants in floral mixes has thus to be completely redesigned, because this choice is often lead by studies about honeybee and bumblebee visitation frequency [88,145]. The redesign of floral mixes could also be particularly efficient in habitats with strong floral resources turn over through space and time (e.g., agricultural areas and heathlands [146,147]).…”

“…The redesign of floral mixes could also be particularly efficient in habitats with strong floral resources turn over through space and time (e.g., agricultural areas and heathlands [146,147]). However, conservation practitioners still lack of information about the empirically tested measures; their choices are thus often driven by the measures benefiting from important commercial advertisement [88]. The choice of floral species should for example take into account the abundance of floral resources throughout the day as well as during the whole flying season [148,149] depending on the species-specific behavior and phenology.…”

Characteristics of blooming, pollen production, and insect visitors of Polemonium caeruleum L. – a species with a potential to enrich pollinator-friendly urban habitats

“…Although this phenomenon is complex, several reasons for pollinator decrease have been identified: pathogens and diseases [14,15], intensification of agricultural production and application of pesticides [16,17], habitat fragmentation [18], and the shortage of floral food resources [19][20][21]. One of the initiatives suggested for mitigating pollinator failure is improvement of floral food resources, both in agricultural [19,22,23] and urban areas [24][25][26].…”