This Week in Nature: The 4th week in September - happy face spiders

What's Happening in Hawaii

during the 4th week in September:

  Can you spot 2 happy face spiders on the underside of this leaf?
Photo: C. Tucker

Hawaiian happy face spiders (Theridion grallator) are rearing their young in 'ōhi'a forests of Maui, Moloka'i, O'ahu, and Hawai'i. Living under the sheltering leaves of kōpiko, pū'ahanui, and other plants, this native spider stays out of sight of insects and birds that prey on it.

There are dozens of different marking displayed by happy face spiders. Though its comical markings might seem hard to miss, in the forest light they serve as camouflage, and humans overlook the tiny happy face, too.

"Adult and keiki eating syrphid on Myrsine at Auwahi, Maui, Hawaii"
Photo by Forest & Kim Starr

The happy face spider; Theridion grallator, is now also known by the Hawaiian name nananana makaki'i. After its discovery by scientists in 1900, it was lost again for three quarters of a century.

Very few spiders display parental behavior, but the happyface spends as long as three months caring for its offspring. A mother shares her leaf with the young and feeds them small flies that seek refuge under the leaf when it rains. Detecting a fly on top of the leaf in good weather, she will creep to the edge and throw a web to snare it.  

To learn more about spiders in Hawai'i, visit the Comprehensive Wildlife Conservation Strategy spider page.

Also, visit the HEAR.org spider page.

Taken from "Hawaii: A Calendar of Natural Events"

published by the Bishop Museum and Kamehameha Schools in 1989