Limitations of Data Reliability and Availability
Most of the data was obtained from reliable sources, such as NPS, Hawaii GIS program, and USGS. Several layers that would be useful in future analyses of this issue were either unavailable from the main data sources, dated, or did not include the area of interest.  For example, after coverage by lava flow invasive grasses, particularly Digitaria ciliaris (Henry’s crabgrass), represent the most serious threat to Ischaemum byrone on the southeastern portion of the Big Island.  Fire in areas infested with non-native grasses may present a threat to grass populations and their restoration. Fire data was not available for HALE or KALA. An updated invasive species layer for all parks would add tremendous value to the suitable habitat analysis and may assist in prioritizing and scheduling weed treatments in preparation for reintroduction plantings.   Other potential threats include grazing and browsing by feral animals (axis deer and goats), which also act as a source of continued introduction and establishment of invasive weeds.

More recent lava flow layers and general flow direction would refine the area likely unsuitable for restoration. Finally, there is little published detailed information on habitat characteristics for Ischaemum byrone other than general elevation, soil, and associated vegetation community.  Some combination of microclimate attributes such as precipitation, aspect, slope, seaspray, humidity, etc. likely have a role in establishment and successful reproduction. The addition of these types of data would also act to refine suitable habitat for the grass.  

The data presented is limited to the demonstration of geospatial concepts that can be used in natural resource management planning. It should not be used to guide on-the-ground management without further review of threats, species and site assessments, federal endangered species policy and management guidelines, and data source credibility. All data within each park was in the same geographical coordinate system and projection before any analyses were performed within the park, but analytical errors could consist of variability in the precision of the measurements. Additionally, sources of misrepresentation could exist within the data due to errors during field measurements or digitizing.

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