Hakalau estimated frass production during a koa moth outbreak, 2013
Dates
Publication Date
2021-05-17
Start Date
2013-04-18
End Date
2013-07-26
Citation
Yelenik, S.G., Perakis, S., Peck, R.W., and Banko, P.C., 2021, Hakalau litter, frass, soil, and understory foliar nitrogen during a koa moth outbreak, 2013-2014: U.S. Geological Survey data release, https://doi.org/10.5066/P9J9QQ96.
Summary
This data release includes metadata and tabular data that document estimates of litterfall, koa moth (Scotorythra paludicola) caterpillar frass production, soil nutrients, and foliar nutrients during 2013-2014 at Hakalau Forest National Wildlife Refuge. During this time, there was a massive defoliation event of Acacia koa (koa) trees by the koa moth. We monitored these metrics in 4 sites that varied in forest structure and composition at Hakalau. We used litter traps to monitor koa litter fall over time and foliar %N to estimate N inputs from litter. We used caterpillar counts, koa canopy estimates, frass production rates, and frass %N to estimate N inputs from frass on the landscape. We used resin bags under koa canopy where frass [...]
Summary
This data release includes metadata and tabular data that document estimates of litterfall, koa moth (Scotorythra paludicola) caterpillar frass production, soil nutrients, and foliar nutrients during 2013-2014 at Hakalau Forest National Wildlife Refuge. During this time, there was a massive defoliation event of Acacia koa (koa) trees by the koa moth. We monitored these metrics in 4 sites that varied in forest structure and composition at Hakalau. We used litter traps to monitor koa litter fall over time and foliar %N to estimate N inputs from litter. We used caterpillar counts, koa canopy estimates, frass production rates, and frass %N to estimate N inputs from frass on the landscape. We used resin bags under koa canopy where frass was directly falling as compared to open grass sites where no frass was falling to monitor soil inorganic N and P over time. Finally we collected foliage of various plant species over time, and tested for %N, under koa versus in the open to track how nutrients in frass fall may track into plants.
Data were collected to estimate frass production during a koa moth outbreak during a massive defoliation event at Hakalau Forest National Wildlife Refuge, an important area for bird conservation in Hawaii. High frass production during such an outbreak event could lead to pulses of nitrogen (N) and phosphorus (P) in the sites. In turn, nutrient pulses could potentially lead to increased growth of native and exotic species in the understory of koa forests. This is especially important in restoration forest areas with exotic grass dominating the understory, as grasses may be able to more quickly take up pulses of N and P from frass fall. We also monitored nutrients coming in the form of koa litterfall. We then tracked the pulse of nutrients into soils and then watched for uptake in foliar nutrients of different plant species to form a picture of those species that might be benefitting from nutrient pulses.
