Bees occur in virtually every terrestrial habitat. Meadows, forests, dunes, wetlands, cities, and even backyard gardens support diverse communities of bees. Wherever and whenever there are flowers, there will be bees. You just have to look. The following is a guide to major habitat types in the northeast and typical bee communities associated with each:
Alpine and sub-alpine
In the northeast, alpine and sub-alpine habitats are islands in the sky. Limited to a handful of the tallest peaks in the northeast including Mt. Katahdin in Maine and the Presidential Range in New Hampshire, alpine and sub-alpine habitats are scattered throughout the region. They are characterized by high-elevation spruce-fir forest, which transitions to stunted forests called krummholz near treeline, and which transitions again above treeline (~1500m) to tundra-like habitat in which only the toughest plants and most cold-hardy bees can survive. Ericaceous shrubs like blueberry, bilberry, and lingonberry (Vaccinium spp.) eke out a living in the nutrient-poor rocky outcrops of this habitat and are key food for Bombus in spring including the common Bombus ternarius, Bombus vagans/sandersoni, and the at-risk Bombus terricola. Thick hairs are an adaptation to cold environments and we also find fuzzy solitary bees like Andrena milwaukeensis and Osmia bucephala in this habitat. Alpine bee communities in the northeast are poorly known and are ripe for future study.
Atlantic coastline and barrier islands
What would be a day at the beach without a little bee watching? Many bees in the region are tied closely to deep sand making Atlantic coastlines great places to find common bees and rarer specialties.
In spring, look on the white baubles of beach plum (Prunus maritima) for Bombus queens, Xylocopa virginica, Andrena, and Colletes thoracicus. If you have ever enjoyed a jar of famous beach plum jelly, thank bees for your sweet treat. Ericaceous shrubs like bearberry (Arctostaphylos uva-ursi), blueberry (Vaccinium), and huckleberry (Gaylusaccia) support specialists including Colletes validus, Habropoda laboriosa, and Andrena bradelyi.
In summer, winged sumac (Rhus copallinum) supports a panoply of insects including the coastal specialty Colletes nudus. On your way to the beach, check out sea rocket (Cakile maritima) for tiny Lasioglossum and the purple clamshell flowers of beach pea (Lathyrus japonicus) for Bombus. The fragrant flowers of beach rose (Rosa rugosa) often host “backyard bees” like Agapostemon virescens and Halictus rubicundus especially if housing developments are nearby.
In fall, lawns of grass-leaved goldenrod (Euthamia) and fountains of seaside goldenrod (Solidago sempervirens) support sand-loving aster specialists like Agapostemon splendens, Perdita octomaculata, Andrena asteris, Colletes speculiferus, and Lasioglossum fuscipenne. Many of these species nest directly in the dunes in recently eroded cliff faces.
Saltmarshes are also good places to look for bees. In July and August, Ptilothrix bombiformis forage on swamp rose mallow (Hibiscus moschuetos) and nest in nearby compacted levees and paths. Sometimes Bombus spp. and Apis mellifera can be seen far out in the saltmarsh taking pollen from saltmarsh cordgrass.
As you walk on the beach, especially in spring and early fall, look out over the ocean for migrating insects. There is evidence from Europe that bumble bee queens disperse long distances over water, but whether or not this occurs in the northeast United States remains unknown. You may also occasionally find honey bees Apis mellifera washed ashore. This occurrence is thought to result from a navigation error that landed them exhausted out over the ocean.
Backyards and parks
Backyards and parks in the northeast can be home to a diverse community of bees, in part shaped by the collective landscaping decisions of homeowners and land managers. Both native and non-native flowers are suitable forage for backyard bees, including blue squill (Scilla), dandelions (Taraxacum), clovers (Trifolium), coneflowers (Echinacea), sunflowers (Helianthus), zinnias (Zinnia), calendula (Calendula), bee balm (Monarda), and many kinds of flowering herbs. Perhaps surprisingly, some bee species are easier to find in backyard gardens and parks than anywhere else including Apis mellifera, the “big 3 Bombus”–(Bombus impatiens, B. griseocollis, and B. bimaculatus), Anthidium manicatum, Halictus ligatus/poeyi, Agapostemon virescens, Andrena dunningi, Colletes inaequalis, and Melissodes bimaculatus. Many of these species are capable of completing their entire life cycles within the confines of a backyard and, as such, have likely benefitted through the large increase in suburban lands over the past decades. As you explore your backyard, keep an eye out for the nests of these bees, which can often occur in bare spots in your lawn.
Deciduous forest was likely the dominant land cover over much of the northeastern US historically. Large swaths of forest were cleared in 19th century for farmland, but rapid afforestation has taken place and now much of the southern region has returned to deciduous forest, albeit in a more disturbed state. Over the past 30 years, exotic plants like garlic mustard and Japanese barberry in combination with pressure from unchecked white-tailed deer populations have usurped the understory of many eastern hardwood forests, with likely negative consequences for forest bees. Still, bee diversity can be high in deciduous forests and many species in our two largest genera, Andrena and Lasioglossum, are strongly tied to this habitat.
Floral resources in the forest peak in spring. Consequently, spring is the best time to find forest bees. Ephemeral wildflowers are a prominent feature of deciduous forests in spring and plants like dutchman’s breeches (Dicentra cucullaria) and Virginia bluebells (Mertensia virginica) are important resources for Bombus queens while they establish their colonies. In sunspots on the forest floor, look for red, black, and yellow Nomada cruising leisurely over the groundsearching for the nests of their Andrena hosts. Although often overlooked, flowering canopies of trees—especially maples (Acer), oaks (Quercus), and tulip tree (Liriodendron tulipifera)—are among the greatest resources to bees in deciduous forests. Trees also provide nest sites for wood-nesting bee species like Augochlora that may utilize snags, dead branches, or rotting logs.
Later in the season as the canopy leafs out, floral resources in deciduous forests are diminished and bee communities generally become less abundant and diverse. In summer, forest bees can be found foraging in clearings and edges on summersweet (Clethra alnifolia) and meadowsweet (Spiraea). In northern and mountainous areas look for Bombus vagans/sandersoni and the at-risk Bombus terricola on flowering raspberry (Rubus odoratus). In fall, goldenrods (Solidago) and asters (Symphyotrichum, Eurybia) in forest clearings support multivoltine genera such as Augochlora, Augochloropsis, and Ceratina, as well as fall aster specialists that don’t mind forested habitats, such as Andrena nubecula and Melissodes druriellus.
Pine barrens are an excellent place to find bees that occur nowhere else, but can be a challenging place to start for a beginner bee watcher. In the northeast, this globally-threatened habitat is defined by sandy, acidic, nutrient-poor soils derived from glacial outwash (in New England) or via past periodic submerging of the Atlantic coastal plain (in New Jersey). Pine barrens are characterized by an understory of ericaceous shrubs and an overstory of oaks (Quercus) and pitch pines (Pinus rigida), which requires frequent disturbance to be maintained. Biodiversity in the pine barrens peaks in the years immediately following disturbance event like fire. Plants growing in pine barrens generally flower more post-fire, and years after burns feature dazzling carpets of flowers throughout the understory, swarming with bees. As a result, bee diversity and abundance in pine barrens also peaks in the years immediately following disturbance. Some of the best examples of pine barrens habitat in the northeast occurs in southern New Jersey, outer Long Island, NY, Montague Sandplains, MA, Cape Cod National Seashore, MA, and Albany Pine Bush, NY.
In spring, the main floral resources in pine barrens are woody shrubs, particularly members of the heath family (Ericaceae), such as blueberry, black huckleberry, and bearberry. Typical bee communities include Ericaceae specialist species like Colletes validus, Andrena bradleyi,and Habropoda laboriosa, whose long faces allow them easy access to nectar in the deep flowers of their host plants. In late-spring, look for rarer sand specialists like Colletes banksi on flowering winterberry holly (Ilex verticillata), Colletes productus and Perdita novae-angliae on maleberry (Lyonia ligustrina), and Melitta americana on cranberry (Vaccinium macrocarpon) in wetlands.
Mid-summer is a quiet time for bees in pine barrens, but look for multivoltine taxa like Bombus and Augochlora on the edges of rivers and wetlands where they may be found on summerweet (Clethra alnifolia) and swamp loosestrife (Decodon verticillatus). On flowering yellow wild indigo (Baptisia tinctoria) and other weedy legumes (Lespedeza) look for Anthidiellum notatum, Megachile campanulae, and Megachile frugalis.
Activity picks up again in late summer and fall when goldenrods and asters bloom in open areas and a new set of specialist bees emerges. Goldenasters (Chrysopsis) and silk grasses (Pityopsis), two aster genera that thrive in deep sand, are particularly productive targets for finding Perdita and other rarities.
Spruce bogs and boreal forest
Wet coniferous forests occur throughout the northeast, including boreal areas in far northern New England. With their acidic soils, these forests can support some of the same ericaceous understory shrubs as drier pine barrens, but with additions of dazzling Rhodora and labrador tea Rhododendron spp. Unlike in pine barrens, the bee community of boreal forests differs since the underlying soil is wet. Little is known about the status and biology of boreal bees in the northeast, but look in more open habitats associated with boreal forest for northern species like Bombus terricola and less commonly seen solitary species like Colletes consors and Colletes impunctatus.
Grassland, pastures, and meadows
Following large-scale deforestation of the northeast for farmland in the 19th century, grasslands became a prominent feature of the landscape for nearly one hundred years. These grasslands were maintained through agricultural disturbance like plowing and mowing which helped maintain the landscape as open fields. Today, as agricultural fields are abandoned or sold and disturbance ceases, grasslands are declining rapidly in the northeastern US, with few high-quality sites remaining in our area.
In general, grasslands are excellent places to find bees. In spring, few resources are generally available in grassland habitats, but shrubby willows (Salix) and cherries (Prunus) along field margins can host a variety of early spring Andrena species. By summer, the true floral glory of grasslands becomes apparent with the appearance of coneflowers (Echinacea), black-eyed susans (Rudbeckia), milkweeds (Asclepias), and bee balm (Monarda) supporting Halictus ligatus/poeyi, a number of Bombus, Megachile pugnata and others. Even common exotic weeds of farm fields, including red clover (Trifolium pratense) and vetch (Vicia sativa) can be useful resources for more adaptable grassland bees, such as declining Bombus fervidus. Goldenrods (Solidago, Euthamia) and asters (Symphyotrichum) steal the show in fall, both in terms of their abundance and diversity of bees supported – in addition to more common species, old farm fields are excellent places to search for Asteraceae specialists such as Andrena asteris, Andrena hirticincta, and Melissodes druriellus.
Orchards and crop fields
Although orchards, crop fields, and community vegetable gardens are entirely human-created, many northeast bees are right at home in these habitats. In orchards of apple (Malus) and cherry (Prunus), look for a diversity of spring-active Andrena, Bombus queens, Colletes inaequalis, Osmia lignaria, and Osmia cornifrons/taurus. Later in spring, a visit to a flowering blueberry field (Vaccinium) will turn up Andrena carlini/regularis, Andrena vicina, the specialist Andrena bradleyi and, if near sand, the specialist Colletes validus. Look in flowering cranberry bogs (Vaccinium macrocarpon) in early July for Melitta americana. Small-scale agricultural fields and community gardens are great places to find Bombus impatiens and Melissodes bimaculatus in summer as well as several specialists: on tomatillo (Physalis) look for Colletes latitarsis, Lasioglossum pectinatum; on squash (Cucurbita) look for Peponapis pruinosa; and on sunflower (Helianthus) look for Melissodes agilis/trinodis and Megachile pugnata.
Given their apparent lack of suitable nesting sites, wetlands might not seem to be stellar bee habitat – however, several bee species in our area can be found nowhere else! Wetland bee action peaks in summer, a time when wetland plants are in bloom and surrounding forested areas offer little in the way of flowers. By early July, flowering of common wetland plants such as pickerelweed (Pontederia cordata), summersweet (Clethra alnifolia), and buttonbush (Cephalanthus occidentalis) draw in a diversity of common summer genera such as Bombus, Ceratina, and Lasioglossum to name a few. Pickerelweed has even more to offer as a host for three specialists—Dufourea novaeangliae, Melissodes apicatus, and Florilegus condignus—and appears to be a magnet for wandering, nectar-hungry Peponapis pruinosa and Anthophora abrupta.
Many bee species can be found in cities, sometimes more easily than in nearby natural areas. This is thought to be due to the diversity of green spaces found in cities—community gardens, parks, arboretums, railroad verges, vacant lots, university campuses—all of which are contain a high diversity flowering plants that bloom throughout the season. Another reason for the high diversity of bees in cities is that some species that once persisted solely on native plants in the wild now make use of common cultivated or exotic plants in cities. For example, dunning’s mining bee Andrena dunningi gathers pollen from exotic Norway maples (Acer platanoides) and bicolored striped-sweat bees Agapostemon virescens use bull thistle (Cirsium vulgare).
Cities are also fantastic places to spot bees not native to north America. Indeed, many of these exotic species are thought to have been introduced at city ports via transoceanic shipping of timber. These exotic bees are usually quite distinctive like the sculptured resin bee Megachile sculpturalis, European wool-carder bee Anthidium manicatum, and European small wool-carder bee Pseudoanthidium nanum. Many of these exotic bees are successful in urban areas because of the prevalence of exotic flowering weeds and ornamental plants from the bees’ place of origin.