Study of the rare wēkiu bug leads to new conservation tool

University of Hawai‘i at Hilo entomologist Jesse Eiben is researching the wēkiu bug, an endemic species found only in the high alpine regions of Maunakea on Hawai‘i Island.

Jesse Eiben
Jesse Eiben

Jesse Eiben is originally from Jefferson, a very small town in rural southern Pennsylvania (the population was 733 for the 2010 census). He grew up in a corn and soybean area of southern Pennsylvania and says he can’t thrive without a solid dose of open space every now and again.

“My family cultivated a keen interest in the outdoors, and we challenge each other constantly to learn and explain more of what we encounter,” he says in an online bio. “The world is here for us to explore, learn from, and protect. Hawai‘i seems to be the perfect place to do that!”

Eiben has been teaching and conducting research at UH Hilo as an applied entomologist for the past year. He teaches insect taxonomy, physiology, and pest management at the College of Agriculture, Forestry and Natural Resource Management. His research relates to the insect diversity and applied conservation management of high alpine ecosystems in Hawaiʻi.

He received a master of science in entomology involving phenology and population growth of insect pests from Oklahoma State University, and a doctor of philosophy in entomology focused on taxonomy, phylogenetics, and growth modeling of endemic Hawaiian seed bugs from UH Mānoa, where he focused on the life history and genetics of the wēkiu bug or Nysius wekiuicola.

His overall research and teaching interests involve using insect diversity and interdisciplinary connections from conservation, animal and plant agriculture, ecology, and taxonomy to apply science-based management tools guiding human changes to the environment.  His primary research is on the wēkiu bug, a rare endemic species found only in the high alpine regions of Maunakea on Hawai‘i Island.

wekiu
Wēkiu bug

Eiben explains the wēkiu bug “is a candidate endangered species due to its decreasing numbers, specialized habitat, constant impacts from human activities, and the myriad of issues associated with global warming.” He is specifically interested in the evolution of the wēkiu and its adaptation to such an extreme environment.

Eiben and Daniel Rubinoff of UH Mānoa’s College of Tropical Agriculture and Human Resources are currently studying the wēkiu using methods that were originally developed to track and control agricultural pests.

Their article, “Application of Agriculture-Developed Demographic Analysis for the Conservation of the Hawaiian Alpine Wēkiu Bug,” was recently published in the prestigious scientific journal Conservation Biology.

Other than the summit of Maunakea, the wēkiu lives nowhere else in the world except in a few laboratories. It’s important to scientists because it is an indicator of natural resource degradation due to human disturbance. It lives on the summit’s cinder cones, some of which have been altered for telescope facility construction. Thus, it is important to be able to monitor its status to assess the environmental impact of existing and future construction.

Eiben on Mauna Kea
Hana Hou, the magazine of Hawaiian Airlines, recently did a feature story on Jesse Eiben and his research.

It’s difficult to find and study the insects in their natural habitat, so Eiben and Rubinoff developed “life tables” to observe them in the lab, discovering at what temperatures the insects grow best, and then finding those temperatures in their native environment. With the predictions created by raising the wēkiu bug in captivity at various temperatures over the course of three years, they have created a predictive model to monitor the growth of the wēkiu bug in its natural habitat.

This method was originally created to study agricultural pests, so farmers would be able to apply insecticides at the optimal time of day and during the correct growth stage on the host plant.

This unique study of the wēkiu can be used to help conservation efforts of rare insects by allowing researchers to optimize their field monitoring methods and timing, only searching for species of concern in places and at times that match rare insects’ preferred conditions.

That means that for the wēkiu bug, there are fewer potential impacts on the summit from looking for the insects at the wrong times, and more efficient and cost-effective fieldwork. Most importantly, if there are ever negative impacts to the wēkiu bug populations, researchers and land managers will be able to discover this decline faster and, hopefully, work to help them recover.

This story is adapted from UH System News.