Missisquoi National Wildlife Refuge Bumblebee (Bombus) Surveys

Study Extent

Sampling

Method steps

1. Development of Initial Survey Instructions Initial Survey Instructions (ISI) were developed through coordination among the USFWS (Dr. Rebecca Longenecker, Laura Eaton, and Maritza Mallek), ESI (Dr. Robert Jean), and SE (Dr. Leif Richardson) via conference calls, email, and document sharing programs. The ISI follows the survey protocol format developed by the USFWS Inventory and Monitoring Program. Survey methods follow USFWS RPBB Survey Protocol guidance (USFWS 2018a) and were subsequently expanded to survey all bumble bee species and record time of collection (Longenecker et al. 2018). The ISI ensure survey protocol and procedural uniformity across Region 5 NWRs and serve as a model for future surveys and for other NWR regions. The ISI, and all data and reports from this project, are available at https://ecos.fws.gov/ServCat/Reference/Profile/109238. Guidance for RPBB Survey Protocol is regularly updated by USFWS at https://ecos.fws.gov/ServCat/Reference/Profile/104984.
2. Habitat and Site Selection Old field, meadow, open grassy areas, and ecotones along forests comprise preferred bumble bee habitats as the areas provide abundant foraging (flowering), and possibly nesting and overwintering habitat. Marshlands and wetlands are potentially used extensively at certain times of year when large amounts of nectar and pollen are available. Based upon species’ preference, SE, USFWS, and MNWR staff selected survey sites within approximately 223 acres (90 ha) of grasslands, marshlands, and wetlands. For clarity, mapping for the eastern and western segments of the MNWR are provided on Figures 2 and 3, respectively in Appendix A and the specific map depicting each site is provided in Table 1. Overall, 12 sites were selected (Table 1; Appendix A, Figures 2 and 3) with 9 sampled during the first sampling period, ten in the second sampling period, and ten sites in the third sampling period. Eight sites (Louie’s Landing, Rte 78S, RT Wetland, S. Young Marsh, Tabor E-01, Tabor E-03, Tabor W-01 and Tabor W-02), were sampled across all three time periods. One site, Tabor E-02, was sampled during two time periods and three sites (Cranberry Pool Dike, Rte 78 N, and Other) were sampled during a single sampling period. Sample sites encompassed a maximum of four acres (1.6 ha) in area (Longenecker et al. 2018).
3. Habitat Assessment A desktop analysis was completed to determine the approximate amount and quality of available habitat potentially suitable for use by pollinators, particularly bumble bees, within the 6,729-acre (2,723-ha) project area. Data acquired for this work include (but are not limited to): historical mapping; historical imagery of the project area using Google Earth mapping; and other readily available commercial, institutional, and governmental sources. Other information includes soil and geologic information and distributional and conservation data for target species and associated habitats and plant communities. On-site habitat assessments followed guidance provided by federal and state agencies and previous bumble bee collection experience. Assessments used a combination of available technology including GIS systems (ESRI ArcMap), handheld GPS units, tablet computers, and programs written by USFWS staff to ensure a high quality, easily interpretable, and universal standard of mapping for field studies and reporting for the target species. This approach avoids some common issues including inconsistent data entry and multiple and incongruous GIS files. As data are collected in the field, QA/QC analysis is completed in “real time”. For this study, initial mapping and associated databases were provided by USFWS. Results of desk-top analysis and on-site habitat assessments were used to guide field surveys.
4. Field Surveys Bumble bee presence/absence surveys, with an emphasis on RPBB, were completed at each survey site across three time (survey) periods for three days each in May, June, and September following approved techniques (USFWS 2018a) and the ISI (Longenecker et al. 2018). Survey techniques included: using binoculars to monitor potential resource patches, using aerial nets to capture specimens, temporarily placing specimens in clear containers, photographing, and releasing specimens. Attempts were made to catch all bumble bees observed in survey plots. A standard 15-inch (0.38-m) aerial insect net with a two- to four-foot (0.61- to 1.22-m) handle was used. Sample areas were delineated, environmental and ecological data were recorded, and all bumble bee species observed were documented, including time of capture and flower species where a bee is collected (if foraging). Sampling for bumble bees occurred outside the optimal window for surveys (15 June – 15 August) based on a special request from USFWS to accommodate refuge and surveyor schedules when bumble bees were still active. At MNWR, samples were collected by two or three surveyors for 60 minutes at each sample site. Further details are provided in the ISI (Longenecker et al. 2018). Efforts were made to sample bees under the following environmental conditions: • Temperatures > 60o Fahrenheit (15.6o Celsius) • < 80 percent cloud cover • Light winds • No rain

1. Bombus
   common name: Bumblebees rank: genus
2. Apis mellifera
   common name: Western Honey Bee rank: species