yellow-banded bumble bee

VU - Vulnerable

NU - Unrankable

SNR - Unranked

not listed

Species in Greatest Conservation Need

Yellow-banded bumble bee is a medium-sized bee but a small bumble bee. It occurs in the United States in the east and the Upper Midwest, and in southern Canada. It was once widespread and common, but its numbers have seriously declined since 2003. It remains widespread but is now uncommon or rare throughout its range except in southeastern Yukon and southwestern Northwest Territories, where it is thought to be still common. It is rare in Wisconsin, where it is given the conservation status of critically imperiled. It is uncommon in Minnesota, where it is not assigned a conservation status.

The female (worker) bee is ⅜″ to 9⁄16″ (9 to 14 mm) in length and stout, 3⁄16″ to ¼″ (5 to 7 mm) wide. The hairs on the top and back of the head are entirely black. There are two large compound eyes, one on each side of the head, and three small simple eyes (ocelli) in a triangular pattern at the top of the head between the compound eyes. The middle ocellus is larger than the the two lateral ones. The face is short and round. It is mostly black but there are yellowish hairs between the compound eyes. The antennae have 12 segments consisting of one basal segment (scape), one small connecting segment (pedicel), and ten more segments (flagellomeres). The scape is long, about half as long as the all of the flagellomeres together. The first flagellomere is slightly longer than the third. The second is about as long as wide. The third is slightly longer than the second. The space below the compound eye (malar space) is smooth and shiny. The tongue is short.

The thorax is densely covered with relatively short hairs. It is always yellow in front of the wing pads (tegulae) and is usually entirely black behind the tegulae. Sometimes there is a yellowish band at the rear.

The abdomen has six abdominal segments and is densely covered with short hairs. The first segment is black, the second and third yellow, and the fourth through sixth black. Some individuals have a yellow fringe on the fifth segment.

The wings and legs are black.

The queen is similar but larger.

The male has seven abdominal segments; 13 antennae segments; and longer, shaggier hairs. The seventh abdominal segment has intermixed black and yellow hairs.

Queen: ⅝″ to ¾″ (17 to 19 mm)

Male: ½″ to ⅝″ (13 to 17 mm)

Worker: ⅜″ to 9⁄16″ (9 to 14 mm)

A wide range of habitats, including woodlands and wetlands.

Queens are seen from late April to early September, workers from mid-June to mid-September.

Bumble bees will sting to protect themselves or their nest. The stinger is not barbed and the bee can sting multiple times.

Overwintering queens emerge from hibernation in late April. They build underground nests.

Larvae are fed both nectar for carbohydrates and pollen for protein.

Adults feed mostly on nectar but also on some pollen.

Sources

7, 24, 27, 29, 30, 82, 83.

Records of yellow-banded bumble bee in western United States are thought to be mis-identifications of western bumble bee (Bombus occidentalis).

Uncommon in Minnesota

Location: Lake Harriet Trial Gardens in Minneapolis