To those familiar only with honeybees or bumblebees, the tiny black shiny yellow-faced bees (Nesoprosopis sp.) hardly seem like bees at all. Nonetheless, they are true bees which gather pollen and nectar from flowers to feed their young. In doing so they pollinate the native plants of Hawaii, including those at Haleakala National Park. Early botanists saw these bees in the millions, but now the upper slopes of Haleakala volcano are one of the few places in Hawaii where these bees are still common. The yellow-faced bee is attracted to the fragrant flowers of the or silversword (Argyroxiphium sandwicense) has a special partnership with this plant - pollinating it so that it can reproduce.

The Haleakala ahinahina resides only on the high alpine slopes of Haleakala National Park. The conditions near the summit make survival a challenge. Hot days, freezing nights, infrequent rain and near zero humidity - the environment of the ahinahina is extreme, but it is perfectly adapted for survival here. It is round and close to the ground to keep the growing center warm. Its leaves are covered with silvery hairs acting as a windbreak to prevent water loss. Once in its life, this amazing plant forms a tall flower stalk, as tall as 6 feet, covered with large reddish flowers. The ahinahina is in the family Asteraceae (sunflower) and each of those large flowers resemble a sunflower. It is these attractive flowers that draw the yellow-faced bees.

Botanists have recently discovered that the ahinahina requires cross-pollination in order to produce fertile seeds. This means that one of these tiny but important insects must visit a flower to collect pollen and then fly to another nearby ahinahina flower and drop off some of the pollen. The bees take some pollen and nectar Without the insect pollinators these rare plants will not be able to reproduce.

This system works well, but dependence on native pollinators makes the native plants vulnerable. The introduction of introduced insects could be responsible for the decline in the ahinahina population. Some alien insects, for example, the Argentine ant, prey on the underground nests of the yellow-faced bee and other native insects. These ants, accidentally introduced in the 1960's, have recently established a few small populations in the upper elevations of Haleakala National Park. In these areas, there has been a reduction in the number of native insects. Decreases in the native insect populations could result in a dramatic reduction of fertile seeds and eventually the possible disappearance of the wild population of ahinahina. Fortunately, there is a group of biologists dedicated to studying the invasive ants and are working on ways to protect the native insects by controlling or decreasing the population of the alien Argentine invaders. With careful research and management both the yellow-faced bee and the Haleakala ahinahina will once again be abundant and thriving in Haleakala National Park.

Genus: Nesoprosopis Order: Hymenoptera, family: Colletidae
At one time found from mountain-top to shoreline, these tiny solitary wasps are now quite rare. Unlike social honeybees, these tiny (1/4-1/2 inch long) Hawaiian bees are solitary - nesting and feeding individually. The upper slopes of Haleakala are home to three species of Yellow-Faced Bees (N. volcanius, N. nivalis, and N. volatilis), all of which feed on and pollinate the native plant species.