New Zealand Journal of Botany ISSN: 0028-825X (Print) 1175-8643 (Online) Journal homepage: https://www.tandfonline.com/loi/tnzb20 Assessing the impact of an introduced bee, Anthidium manicatum, on pollinator communities in New Zealand J Soper & JR Beggs To cite this article: J Soper & JR Beggs (2013) Assessing the impact of an introduced bee, Anthidiummanicatum, on pollinator communities in New Zealand, New Zealand Journal of Botany, 51:3, 213-228, DOI: 10.1080/0028825X.2013.793202 To link to this article: https://doi.org/10.1080/0028825X.2013.793202 Published online: 18 Jul 2013. Submit your article to this journal Article views: 825 View related articles Citing articles: 8 View citing articles Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=tnzb20 New Zealand Journal of Botany, 2013 Vol. 51, No. 3, 213Á228, http://dx.doi.org/10.1080/0028825X.2013.793202 RESEARCH ARTICLE Assessing the impact of an introduced bee, Anthidium manicatum, on pollinator communities in New Zealand J Soper and JR Beggs* School of Biological Sciences, University of Auckland, New Zealand (Received 7 December 2012; accepted 2 April 2013) Introduced pollinator species may exacerbate the problems faced by pollinator communities, so the detection in 2006 of a new solitary bee, Anthidium manicatum, to New Zealand was concerning. We assess whether establishment of this wool-carder bee presents potential risks to native flora and fauna by recording its current distribution, which plant species it visits, which insects co-occur at these plants, and identifying which species this territorial bee attacks. Anthidium manicatum is now widespread in urban New Zealand. More than 80% of the plants visited by A. manicatum were exotic species (predominantly Lamiaceae and Plantaginaceae), although it also visited native species of Veronica (Plantaginaceae) and Lobelia (Campanula- ceae). Anthidium manicatum primarily interacted with other introduced bees. Native Lasio- glossum bees were seldom attacked and only for short durations. Further research is required, particularly on weeds, but we suggest that A. manicatum does not present a major direct threat to New Zealand’s native flora and fauna. Keywords: alien invasive species; distribution; pollination; pollen load; Anthidium manicatum; wool-carder bee; Lamiaceae; Plantaginaceae; Apis mellifera; Lasioglossum Introduction Albrecht et al. 2012). This leaves the web still Degradation of the environment has led to well connected, but the species interacting shift the decline of pollinator communities in many from native to exotic. However, not all species parts of the world, coupled with a decline in added to a community are necessarily polylectic, plants reliant on animals for these vital repro- so identifying the range of native and exotic ductive services (Winfree et al. 2009; Potts et al. interactions that a new arrival engages in will 2010). Introduced species may be one of the help to assess the threat it poses to the structure drivers of this pollinator decline, but it is not of the pollinator community. immediately obvious whether an introduced Bees are the most highly adapted of all pollinator will disrupt native plantÁpollinator insect flower visitors (Kevan & Baker 1983) and interactions, or just seamlessly integrate into are among the most important pollinators of pollinator webs, perhaps even enhancing the many flowering plants including agricultural reproductive success of plants (Tylianakis 2008). crops (Michener 2007). Several species of bee Polylectic exotic pollinator species (species of have been widely introduced outside their bees that take pollen from a wide variety of native range for pollination services, whereas plants), particularly honeybees (Apis mellifera many other species are finding their ways into L., Apidae), tend to end up dominating highly new environments as a result of accidental or invaded pollination webs (Aizen et al. 2008; indirect introductions (Strange et al. 2011). *Corresponding author. Email: [email protected] # 2013 The Royal Society of New Zealand 214 J Soper and JR Beggs Recently there has been increased concern 2011) (Fig. 1). Native to Europe, western Asia regarding the possible impacts of introduced and northern Africa, A. manicatum is a solitary bees, including: competition with native polli- species that has been accidentally introduced nators for floral resources and nest sites, polli- to South America, the USA, Canada, the Canary nation of exotic weeds and disruption of the Islands, Siberia and New Zealand (Proshchalykin pollination of native plants (Goulson 2003; 2007; Gibbs & Sheffield 2009). It was first dis- Paynter et al. 2010). Most research to date covered in Napier and Nelson in 2006 (Donovan has focused on the impacts of managed bees on 2007), adding to New Zealand’s comparatively native bee communities, whereas little is known small bee fauna of 40 species, most of which are about the potential impacts of unintentionally endemic (Donovan 2007; Howlett & Donovan introduced bees (Strange et al. 2011). 2010). In New Zealand, other insect pollinators The wool-carder bee (Anthidium manicatum such as moths, flies and beetles, as well as L., Megachilidae), is globally the most wide- birds, play an important role in pollination spread unmanaged bee species (Strange et al. (Newstrom & Robertson 2005; Kelly et al. Figure 1 Distribution of Anthidium manicatum in New Zealand, July 2012. This bee was first detected at Napier and Nelson in 2006. The most recent detections were at Gisborne and Masterton in 2012. Top right shows three of the five abdominal spines the male wool-carder bee uses to attack other floral visitors. Bottom right shows female bee carding fibre from Stachys sp (lamb’s ear; Lamiaceae) to make her nest. Photos: Eve Manning. Impact of introduced wool-carder bee in New Zealand 215 2006, 2010). Native pollinating insects may general public using websites, newsletters, be particularly vulnerable to disruption by magazines and newspaper articles. New records A. manicatum. were gathered between 2009 and 2012, and Male A. manicatum are territorial and those that were verified (from specimens and aggressively defend patches of flowering plants photographs and/or entomological experts) as mating territories, attacking intruders that were added to our distribution data. enter the territory with their sharp abdominal spines (Wirtz et al. 1988). This bee is described as polylectic, collecting pollen from various kinds Study site of flowers, although the most common plant Observations of A. manicatum behaviour were associations are with members of the Lamia- conducted at the Auckland Botanic Gardens ceae, Scrophulariaceae and Fabaceae (Muller (ABG) in Manurewa, Auckland, New Zealand 1996; Maier 2009). As with other members of the (37.0102298S and 174.907158E). The ABG cover tribe Anthidiini, female A. manicatum engage 64 hectares, containing over 10,000 species of in elaborate nesting behaviours, stripping pub- plants (of which 2357 species are native to escence from the leaves and stems of various New Zealand), and are separated into areas plants, which they roll into balls and carry back containing similar types of plants. This study to pre-existing cavities to construct their nests. was carried out predominantly in the Perennials Anthidium manicatum is in flight over the sum- Garden, the Herb Garden and the New Zealand mer months, during which time there can be a Natives areas, because they were adjacent to second or third generation, and they over-winter each other, easily accessible and contained a as pre-pupae (Payne et al. 2010). range of exotic and native plant species. The main aim of this study was to investi- gate whether the establishment of A. manicatum in New Zealand presents any potential risks to Plant associations of A. manicatum native flora and fauna. To meet this objective, During the time that fieldwork was carried out first we documented the known range of at the ABG, we documented all plants that A. manicatum in New Zealand, incorporating A. manicatum was observed visiting. Addition- new distribution records. Second, we examined ally, weekly examinations were made in sec- whether A. manicatum would be associated with tions of the ABG that were not included in exotic and/or native plant species by under- the study area. New plant associations were taking floral visitor counts at the Auckland also recorded by members of the public and Botanic Gardens. Finally, we observed which entomologists, and those that were verified insect species A. manicatum co-occurred with on were added to our data set. flowers and looked at whether the novel beha- viour of A. manicatum presented any potential risks to the foraging of native bees. Flower visitor community We recorded the floral visitors to a range of native and exotic flowering plants based on the Materials and methods methods developed by the Pollination Biology Distribution Research Group at Landcare Research (www. Existing distribution records of A. manicatum landcareresearch.co.nz/research/biocons/polli in New Zealand were collected from the insect nation/: accessed 29 July 2009). Seven exotic collections of 10 institutes and private indivi- plant species that A. manicatum was known to duals throughout New Zealand in September visit, and 18 native plant species that were 2009. Additionally, new records were solicited in flower (including two Hebe cultivars), were from specialist entomological groups and the selected at random along 38 transects at 216 J Soper and JR Beggs the ABG between 25 November 2009 and 10 allow for comparison of pollen loads between June 2010. Where possible, five replicates of bees collected on native versus exotic plants and each plant species were included, although also to ascertain whether they were collecting when plants had stopped flowering they were pollen from both exotic and native plants in the not always able to be immediately replaced. same pollen-collecting trip. Bees were placed in a We stopped at each plant, chose an area of the container with 1 ml of 75% ethanol, which was plant that was in full sunlight, and recorded gently shaken to remove pollen.