Journal of Insect Conservation https://doi.org/10.1007/s10841-019-00148-8 ORIGINAL PAPER Wastelands: their attractiveness and importance for preserving the diversity of wild bees in urban areas Lucyna Twerd1 · Weronika Banaszak‑Cibicka2 Received: 7 June 2018 / Accepted: 25 March 2019 © The Author(s) 2019 Abstract Urban wastelands are important substitute habitats for many insect species, but their value for the protection of wild bees is still poorly studied. We assessed species richness, abundance, and the diversity of wild bees in wastelands that difered in area (2–35 ha), stage of ecological succession, location (suburbs or closer to the city centre), and history of land use. In the investigated plots, we recorded 42% of all bee species reported from Poland. The attractiveness of wastelands was positively correlated with the coverage of blooming herbs, coverage of shrubs and low trees, and the area of the wasteland. An increase in isolation of the habitat patches, the percentage contribution of alien species, annuals, and low grasses (< 25 cm) nega- tively afected the diversity of Apiformes. Considering the history of land use, we found that the bees were most attracted to wastelands resulting from extractive industry (sand and clay pits), and grassy habitats located in the suburbs, e.g. at sites grazed earlier by sheep. Wastelands in areas directly infuenced by the chemical industry were the least attractive to bees. Analyses of quantitative and qualitative similarity of bees in various habitat types showed that three habitat types were the most similar to grasslands in the suburbs (the least disturbed habitats): degraded grasslands located closer to the city centre, extraction pits, and old felds. The presented results indicate that urban wastelands, including some post-industrial sites, can be important secondary habitats for wild bees. Thus, proper management of urban natural resources should cover both the formally managed areas and the so-called unproductive spaces, which have been undervalued so far. Keywords Apiformes · Biodiversity · Urban wastelands · Ecosystem services Introduction a positive role in preserving biodiversity and often func- tion as secondary habitats for some species (Lundholm and The growth of urban areas is observed worldwide, and the Richardson 2010; Menke et al. 2011; Holzer 2014; Eckert expanding cities cause signifcant changes in the environ- et al. 2017; Hall et al. 2017; Banaszak-Cibicka et al. 2018). ment (Aronson et al. 2014; Shochat et al. 2010; McDonnell Urbanization transforms a homogeneous landscape into a and Hahs 2008; McKinney 2002). Although urbanization mosaic of pavements, buildings, and urban green areas: not threatens many animal species (McKinney 2006, 2008; only managed (e.g. parks, gardens), but also various types Fortel et al. 2014; Concepción et al. 2015; Hamblin et al. of wastelands. Although the word wasteland has many 2018), numerous studies show that urban areas also play meanings, usually they are perceived as apparently empty, neglected (Gandy 2013) abandoned sites with spontaneous Electronic supplementary material The online version of this vegetation. They are found in areas afected by industrial article (https ://doi.org/10.1007/s1084 1-019-00148 -8) contains activity (Gallagher et al. 2011; Kattwinkel et al. 2011), after supplementary material, which is available to authorized users. demolition of industrial buildings and warehouses, and near abandoned infrastructure (Albrecht et al. 2007; Fischer et al. * Lucyna Twerd [email protected] 2013a, b; Gardiner et al. 2013). Moreover, in the course of urban development, farmland is commonly transformed into 1 Department of Ecology, Institute of Environmental built-up areas, which become signifcant (in terms of area) Biology, Kazimierz Wielki University, Ossolińskich 12, components of urban open space. 85-093 Bydgoszcz, Poland Wastelands covered with plant species growing without 2 Institute of Zoology, Poznań University of Life Sciences, human control are often overlooked in protection schemes. Wojska Polskiego 71C, 60-625 Poznań, Poland Vol.:(0123456789)1 3 Journal of Insect Conservation However, despite the fact that the image of these areas is spaces”) is not only poorly studied but until recently also often negative, they may be important due to their high fo- marginalized in respect of their environmental value. ristic diversity (Maurer et al. 2000; Zerbe et al. 2003). Lack Urban habitats can be considered as attractive to bees of management of urban wastelands encourages varied plant when they provide habitat features necessary for their sur- populations to be maintained (Öckinger et al. 2009). Apart vival, including the abundance and diversity of fowering from native species, urban wastelands often harbour exotic plants as forage and a variety of suitable nesting sites. The plants (Godefroid et al. 2007; Muratet et al. 2007). Waste- attractiveness of habitat types can be assessed on the basis lands are also very dynamic in space and time. They appear of the observed number of bee species. and disappear as a result of demolition or construction of Spontaneously developing wastelands ofer a number of residential buildings and changes in infrastructure and green features which are benefcial to bees and do not occur in areas. Wastelands of diferent ages include diferent stages developed areas. One such feature is permeable soil devoid of vegetation, ranging from pioneer to pre-forest stages, and of vegetation, which provides convenient nesting sites for consequently harbour diferent communities of plants and many species. Another crucial aspect is the presence of animals. Other important factors are the distance between native psammophilous or ruderal plant species which do not diferent wasteland areas and their isolation. Higher isola- require care (such as watering) and are an important source tion and distance between convenient habitats act as a factor of food, especially in the summer. Hence, due to the difer- limiting the occurrence of some species, especially small ent habitat conditions, wastelands complement and support bees whose foraging range is approx. 150–600 m from the natural bee resources found in urban ecosystems. Moreover, nesting site (Gathmann and Tscharntke 2002). Connectiv- at the city scale, they usually constitute a signifcant part ity between wastelands infuences the biodiversity of waste- which should be taken into account in urban planning. lands, although to a lesser extent than the local features Our study was aimed to assess the environmental value (Bonthoux et al. 2014). of urban wastelands for the survival and protection of wild The variable character of towns and cities (e.g. in respect bees. Hence we determined: (1) which types of wasteland of their size, age, population density, and rate of urbaniza- support a high diversity of Apiformes; (2) which features tion) results in various forms and locations of wastelands of wastelands are crucial for their attractiveness to bees; (3) in urban areas (Rupprecht and Byrne 2014). For instance, which bee species are indicators of the studied habitat types; recently created towns are characterized by a larger contri- and (4) how the wastelands should be managed, particularly bution of open, unmanaged habitats (Hahs et al. 2009), as in the context of biodiversity preservation and development compared with older administrative units. Simultaneously, in urban habitats. diferences in the shape and size of wastelands may infu- ence the role played by them in the landscape. Neverthe- less, irrespective of their size, they “fll” and supplement Materials and methods the environmental space of towns and cities, simultaneously ensuring the continuity of resources, which is regarded by Study area and study sites many authors as a signifcant factor afecting biodiversity (Niemelä 1999; Savard et al. 2000). Field research was conducted in 2016 and 2017 in 14 waste- Wild bees, as the most common pollinators, provide cru- lands located in the city of Bydgoszcz in northern Poland cial ecosystem services in both natural and anthropogeni- (53°7′24.6″N, 18°0′27.43″E). Although Bydgoszcz is one of cally modifed habitats. In urban areas, protective measures the largest cities in Poland (population about 360,000, area are undertaken more and more often to improve their living 176 km2), it has remarkable environmental values thanks conditions (construction and installation of bee houses) and to its location on the river Brda, at its confuence with the to increase the amount and availability of food resources Vistula, and the high forest coverage of the adjacent areas. (propagation of bee forage plants, green roofs) (Colla et al. The city is characterized by highly variable land relief, with 2009; Tonietto et al. 2011). However, to a large extent, pro- fat areas of the Vistula valley and its broad glacial valley tective measures are undertaken in formally managed green as well as steep edges of the valley and undulated tops of areas, i.e. in urban parks, public and private gardens, and so- moraines. As a result of the shape of the terrain, the city is called “ecological areas”, which are partly protected. That is located at an altitude of 28–96 m. why we know a lot about the role of managed urban green For this study, seven types of wastelands were selected: areas (Matteson et al. 2008; Lermann and Milam 2016; [A] degraded grasslands in the suburbs; [B] degraded grass- Lermann et al. 2018; Normandin et al. 2017) and urban lands closer to the city centre; [C] clay and sand quarries; forest ecosystems (Carper et al. 2014; Banaszak-Cibicka [D] old felds; [E] sites where industrial buildings or ware- et al. 2018) in shaping the diversity of bees. In contrast, the houses had been demolished; [F] wastelands in a former signifcance of unmanaged areas, so-called “unproductive military training area; and [G] wastelands directly afected 1 3 Journal of Insect Conservation by chemical industry (Figs. 1, 2, 3). We analysed each type suburbs, bordering with multi-family residential build- of wastelands in two sites. ings (about 50–100 from blocks of fats), are often used The wastelands examined were open spaces with high for sports and recreation.