This online field guide is designed to help you learn how to find, identify and learn about wild, living bees in the northeastern United States.

Our guide is designed to open new avenues to learn about wild bees in the northeast. It is designed to identify living bees and should not be used to identify pinned collections of wild bees. Even still, many bees can be difficult to identify on the wing and we recommend supplementing your field observations with voucher specimens (see below) to get the most out of this guide. T. B. Mitchell’s (1960) dichotomous keys to bees of eastern North America are an excellent starting point for identifying pinned specimens, but be aware that Mitchell’s taxonomy is sometimes outdated, more so for some groups (e.g., Nomada, Lasioglossum [Dialictus]) than for others.

For tips on how to watch and identify bees, including gear recommendations, visit this other page.

Table of contents

1. Getting started
2. Which species does the guide cover?
3. Who is this guide for?
4. On taking voucher specimens
5. What region does the guide cover?
6. Where can I submit my observations?

Getting started

Identify

Resources to help you distinguish bees from non-bees and to point you in the right direction to identify an unknown bee from a photograph.

Explore

Detailed profiles including field marks, annotated photographs, and natural history summaries for all the bee families, genera, and species covered in this guide.

Learn

Resources about how to watch bees, an overview of bee habitats, and other guides to identifying flower-visiting insects that we like.

Which species does the guide cover?

Our guide covers more than 50 common and distinctive bee species in the northeast from nearly 30 different genera. For each species, we have written a profile that contains all the information that you need to unambiguously identify the species (or species pair) in the field—appearance, phenology, range, nesting and foraging habitat. Check back often: we plan to continually add and refine species accounts to increase the scope of our guide.

Format of species accounts

• Scientific name: The title of the species account is the latin binomial name of the species. For a primer on bee taxonomy and classification, click here.
• Introduction: A brief overview of the main field marks that we use when identifying this species in the field.
• Range: The species’ range within the northeast United States. Our guide covers species from Virginia north through Maine and west through Pennsylvania.
• Phenology: When this species is most likely to be observed on flowers.
• Appearance: The main morphological characteristics used to identify the bee in the field. Separate male and female descriptions are given. This section is accompanied by annotated photographs of living bees pointing out the key morphological characters.
• Similar species: Other bee species that may be confused with the described species. In most cases, we limit this section to species within the same genus.
• Nesting: Pertinent nesting habitat and nesting behavior of this species. This section is designed to help you locate nests for study and does not include specific information on nest architecture.
• Foraging: Preferred floral resources used by this species. We limit the list to plant species or plant genera that the bee species is typically seen on, with notes of particular plant species that seem to be favorites based on our observations.
• Natural enemies: Cleptoparasitic bees either known or presumed to be associated with the covered species. Additional nest associates are given, if known.
• References: References for literature consulted during writing.

*Throughout species accounts, we strive to use non-jargon terminology, but in the cases where we use a specific anatomical term is more articulate and precise, the definition can be found at this page.

Who is this guide for?

Everyone! We have geared our guide towards anyone–naturalists, scientists, gardeners, restoration practitioners, land managers—interested in learning how to identify common wild bees in the northeast. Regardless of where you are in your bee watching journey, we hope this guide enriches your observations of wild bees, motivates you to search for bees you have not seen before, and enables you to keep lists of bees that you see on bee watching trips.

On taking voucher specimens

For the beginner bee watcher

Please do not feel the urge to collect specimens—the whole point of our guide is to shift the focus towards non-lethal observation. You can use the field marks that we have outlined to build your confidence identifying many bee species in the field.

As you develop your skills, you may wish to identify bees not covered in this guide or differentiate between pairs of species that aren’t easily separable by field marks alone. To do so, we recommend making a reference collection, which is a collection of pinned and identified specimens of every species (both males and females) and identifying them using Mitchell’s (1960) dichotomous keys to bees of eastern North America. Even when lethally collecting, your field ID skills can come in handy, helping you to target individuals of bee taxa that you can’t ID in the field or aren’t familiar with – responsible collectors sample thoughtfully and take only what they need to help them better understand an area’s bee fauna.

For scientists and land managers 

For the general study of bees, we emphasize that identifications using field marks should complement, not replace, identification using a microscope. Any study or monitoring program identifying bees using field marks should always take a small number of voucher specimens to “back up” field ID, at least until the observers are confident identifying the target species on the wing. We outline an approach to designing and conducting studies on single species of bees in this research paper. 

At present, it is not possible to use field marks to identify entire communities of wild bees to species in the field. Species identification of some bee groups is only possible under a microscope, and the taxonomy of other groups in North America is still unresolved (meaning that the legitimacy of some species or the relationships between species is unclear, so it is not possible to draw an unambiguous link between microscopic characteristics and features observed in the field). Studies wishing to characterize the entire community of bees present in an area or work with challenging groups (such as Lasioglossum [Dialictus] and Nomada) should always work with trained taxonomists for identifications. 

What region does the guide cover?

Our guide covers northeast and mid-Atlantic states in the U.S. This is the region in which we live and work and in which we are most familiar with bee communities. In addition, bee taxonomy in this region is relatively well-resolved, so we were able to verify field marks with pinned voucher specimens. Although we focus on bees of the United States, our guide is applicable to southeastern Canadian provinces, too.

Where can I submit my observations?

Presently, the best place to contribute your observations is to iNaturalist. Unlike checklist-based websites like eBird, you will need a photograph of each species record you plan to submit. Submit separate observations for photographs of different individuals observed at the same location, unless you are entirely positive that they are the same species and sex!