2019 Bee Monitoring Results

Clare Maffei and Sam Droege

The following is excerpted from a preliminary report, where referenced tables and figures can be found.

Over the course of the 2019 season, 6,012 bees from 5 families, 32 genera, and 177 species were collected (Table 2) over the course of 6 months (April through September) (Table 4) by the participating sites (Table 4). Of the bee species collected, 121 species (68%) were represented by fewer than 10 individuals, and of these, 62 (35%) were represented by singletons. Augochlorella aurata was the most abundant bee in the collection, representing 40% (2,423) of the specimens. The next most common bee collected was Ceratina strenua with 588 specimens (approximately 10% of overall collection).  Tables of bee species for each site were created (see individual state chapters).  “Destroyed” indicates either extra labels were printed inadvertently or a specimen experienced damage and was lost from its pin.


Species richness varied greatly by site and sampling effort (Figure 1). Estimated actual species richness generated using the USGS SPECRICH calculator (Burnham and Overton, 1979) was considerably higher than the observed species richness for most sites. Five transects in two states comprised half of the data (MA: Red Barn Road (12%), Barrett Farm Road (10%), Osprey Pole (9%); NY: Alley Cat (11%), Draperies (10%)).


Certain species of interest were collected (Table 3). Two rare sand specialist species and one possible sand specialist species were collected in Maryland and Massachusetts. Lasioglossum arantium is a Regional Species of Greatest Conservation Need (RSGCN) and on several State Wildlife Action Plans (SWAP’s) and was collected in Pocomoke State Forest, MD (Lasioglossum georgeickworti, another RSGCN species, was identified at several sites in 2018 but not in 2019). Perdita bradleyi was collected at Pocomoke State Forest, MD in 2018 and again in 2019. Andrena braccata was collected at the Linda Loring Nature Foundation site in MA and is suspected to be a sand specialist, but more research on the life history of this species is needed. Habitat associations for most species is based on collection and observation notes, more comprehensive life history study is required for nearly all native bees.


Besides the habitat specialist species, two rare species and one possible new species were collected in 2019. Lassioglossum floridanum is not rare in MD (50 were collected at Pocomoke the 2019 season) but is rare elsewhere. Andrena regularis (NH and NY) are uncommon in collections. One Nomada specimen was collected that may be a new species. This was sent to other taxonomists for their assessment.


Pocomoke State Forest, MD found the most rare and specialist species in 2019.

Table2 2019 Report.jpg

The number of specimens collected from all sites within each family and genus

Table2_Table 2 number of specimens colle