Based on data from 170K bee collection records from 2000-2016, we build graphs showing the abundance (phenology) of 49 bee genera in the Mid-Atlantic area of North America

1. Phenology of Bee Genera:
MidAtantic States: USA
Charts, by week, for each Genus based on USGS BIML records

2. Objective
• Present a summary of counts (corrected for effort) per week for each
genus of bee found in the Mid-Atlantic area based on 175888
specimen records in the USGS Bee Inventory and Monitoring Lab’s
database.

3. Records
• Specimen records came from USGS Native Bee Inventory and
Monitoring Lab’s (BIML) collections from 2000-2016
• Specimens records from NJ, DE, DC, MD, VA, WV, PA were extracted
• Records included a mix of hand-netted, bowl-trapped, malaise
samples from a variety of projects
• 7147 collection events were used
• With rare exception, all bees captured during a collection event were
identified to species
• 175883 specimens went into the analysis

4. Data Massaging
• Specimens were assigned a Julian Week Number based on the date
the capture event for that specimen was started.
• The number of specimens collected for a genus for a particular week
were divided by the pooled number of all collection events across all
the years that occurred during that week (to better normalize the
data as numbers of collect events varied across weeks…particularly at
the beginning and ends of the seasons).
• No efforts was made to correct for geographic location of records.
• Geographically, numbers of records declined with distance from the
BIML lab in Beltsville, Maryland.

5. Graph Interpretation
• X-axis represents all the weeks in a year. The letters represent the
first letter of the months involved. If more than one month occurs
within a given week then the month with the most days was used as a
label for that week.
• Y-axis represents the number of bees per collection event times 100.
• The blue line connects the calculated bees per collection event.
• The brown line represents the LOESS smoothed line of those data
points (PeltierTech Excel AddIn, 9 points, alpha 0.193).
• Graphs are presented alphabetically by bee genus.

6. Records for each Genus, but only from Maryland
data(didn’t have time to combine all the states), to
give you a feel for relative abundance of bees in
each Genus
Agapostemon 5382 Ceratina 13661 Holcopasites 24 Peponapis 155
Andrena 19637 Chelostoma 8 Hoplitis 717 Perdita 183
Anthidiellum 46 Coelioxys 209 Hylaeus 2037 Pseudoanthidium 14
Anthidium 353 Colletes 831 Lasioglossum 29433 Pseudopanurgus 27
Anthophora 157 Dieunomia 68 Megachile 2010 Ptilothrix 1143
Apis 2162 Dufourea 1 Melecta 1 Sphecodes 274
Augochlora 1998 Epeolus 38 Melissodes 2037 Stelis 43
Augochlorella 6551 Eucera 187 Melitoma 178 Svastra 83
Augochloropsis 275 Florilegus 35 Nomada 4719 Triepeolus 48
Bombus 2943 Habropoda 164 Osmia 7648 Xylocopa 586
Calliopsis 2269 Halictus 7252 Panurginus 55 Melitta 11
Cemolobus 1 Heriades 103 Paranthidium 1 Macropis 1