OMKM's Blog & Management Updates
It's Wēkiu Bug Season!
Found only on alpine cinder cones of Maunakea, the wēkiu bug (Nysius wekiuicola) was discovered in 1979. Regular monitoring of this native species was begun in 2002; with additional monitoring of potential invasive species threats to the bug included beginning 2007. In 2011 the wēkiu bug was removed as a candidate for listing under the Endangered Species Act due to "conservation efforts that remove or reduce the threats to the species".
Monitoring and conservation efforts occur year-round. Traps to detect non-native arthropods are kept continuously in Halepōhaku facilities and checked monthly. All facilities, including observatories, are monitored at least quarterly; while wēkiu bug and invasive species monitoring on pu'u and lava flows occurs at several times each year. Additional details are in the Maunakea Invasive Species Management Plan and much more work is done by Dr. Jesse Eiben of the University of Hawai`i at Hilo.
As is common with many arthropods, both native wēkiu bugs and non-native species may be very common one year and much less common the next. In 2013 for example, wēkiu bug catch rates were among the greatest ever observed while in 2014 catch rates were among the lowest ever. So far in 2015 it seems like catch rates are much greater than in 2014, while non-native species catch rates are lower than in 2014. We'll know more however, in a few weeks.
`A`ole ants, No ants! Ants are the greatest threat to wēkiu bugs. There are NO native ants in Hawaii and NO known ant populations above Halepōhaku. You can help by ensuring your vehicle and belongings are clean (free of soil, plant, animal, or insect material) before coming to Maunakea other wild areas in Hawai`i.
Below are examples of some of the trap types used to catch insects on Maunakea. What type of trap is placed where depends upon many factors, including both what has been caught there in the past as well as what native species are likely to be present. Your kōkua (assistance) is appreciated; please do not disturb these traps if you see them. They are labeled for identification and weʻll be back in a few days to retrieve them.
Wēkiu bug trap: nested cups with moisture, habitat, and food (bait).
Pitfall trap: cup partially filled with food-grade propylene glycol (green fluid in photo) and water to catch crawling insects.
Pan trap: yellow bowl partially filled with food-grade propylene glycol (green fluid in photo) and water to attract and catch flying insects.
Peanut butter, spam, jam on chopsticks: variety of bait (lipid, protein, and carbohydrate) to attract insects. Sometimes used to feed hungry biologists.
Cockroach trap (a sticky surface): baited with peanut butter, spam, and jam again to attract insects.