I was thrilled to stumble on Hawaiian yellow-faced bees — nalo meli maoli — on lehua flowers on Hawaiʻi Island. The native bees are small — less than a quarter inch long — and look more like black-brown wasps that have a yellow face.
Honey bees — which are much larger — are not native to the Hawaiian Islands — the first hives were brought to O’ahu in 1857. The only bee to reach the Hawaiian islands on its own is the yellow-faced bee Hyleus. Over eons of time the original founders evolved into 63 known species endemic to the Hawaiian islands. Hawaiian yellow-faced bees are solitary and do not live in colonies like honey bees.
When I posted my photos to facebook, entomologist Karl Magnacca confirmed they were native yellow-faced bees — nalo meli maoli. He speculated they were either Hylaeus difficilis or Hylaeus volcanicus — two relatively common species on Hawaiʻi Island. In the 1900’s famous biologist R.C.L. Perkins who wrote the monumental work Fauna Hawaiiensis called Hawaiian yellow-faced bees “almost the most ubiquitous of any Hawaiian insects.” Sadly, this is no longer the case. Recent surveys of yellow-faced bees by Karl Magnacca showed that most Hawaiian yellow-faced bee species are in decline, many are extremely rare, and several are possibly extinct.
Of the 63 species, 7 have been listed as endangered: Hylaeus anthracinus, H. longiceps, H. assimulans, H. facilis, H. hilaris, H. kuakea, and H. mana. Hawaiian yellow-faced bees can be found in a variety of habitats including coasts, dry forests and shrublands, mesic and wet forests, and subalpine shrublands. All Hawaiian yellow-faced bees depend on an intact community of native plants and are mostly absent from habitats dominated by non-native plant species. These bees require a habitat with a diversity of plants that flower throughout the year so that a consistent source of pollen and nectar is available. Many species nest in the ground, but some nest in hollow stems of plants; the availability of nest sites is another important habitat requirement for these animals.
The Xerces Society — For Invertebrate Conservation
Hawaii’s Native Bees – Nalo Meli Maoli by Karl Magnacca, O‘ahu Army Natural Resources Program
Hawaii BeeKeeper’s History