It's been a month since my job with NEON ended, and as another chapter of my life draws to a close I wanted to take one last look back at the various data collection activities we carried out. Each of the protocols below had an extensive document describing its execution in detail, which we had to be brought up to speed on before performing the protocol (and would not-infrequently refer to in the field for clarification). I probably don't remember them perfectly so I might get specifics wrong, and also the protocols are always subject to updating and revision based on best practices and experience gained in the field, so don't rely on this for future NEON field seasons!
Of the protocols, there were two broad categories: one type was repeated at a certain cadence – weekly, fortnightly, monthly – while the other was confined to certain windows of time in the year during which we'd try to get it done for as many plots as possible. I'll start with the repeating protocols, as those were the constant background cadence we became used to, then go through the season in chronological order covering the rest in a second post (as this one ballooned to longer than I expected). I've tried to include some photos where I can, but I didn't always remember to take them for every protocol.
Phenology (PHE)
Phenology (a word I hadn't heard before starting with NEON) is, according to Merriam-Webster: “the study of periodic events in biological life cycles and how these are influenced by seasonal and interannual variations in climate, as well as habitat factors (such as elevation).” For us, it involved a weekly walk along an eight-hundred-meter stretch of road and checking on…I think it was some two hundred individual plants along the way. For each plant we'd record various data (though the specifics varied by plant type). Some typical data points would be things like does this plant have any new leaves growing? Are any of its leaves changing color or falling? Does it have flowers? (And if so, how many, and what fraction are fully open?) Likewise for fruit – are any present, and how many of them are ripe?
Thankfully, for our sanity, we didn't have to count every single instance of a flower or fruit on a plant, as the survey divided things up into bins of increasing numerical size:
- <3
- 3–10
- 11–100
- 101–1,000
- 1001–10.000
- >10,000
On small shrubs it'd be easy to say, for instance, that there were only two fruits (<3), while on some large trees (especially ʻōhiʻa) we could easily see upwards of ten thousand young leaves budding at certain times of year. (ʻŌhiʻa leaves come in bunches of a certain average amount, so we could simply count those and multiply.)
For instance, above is a closeup of a pūkiawe plant, one of the species we looked at. It grows as a shrub to a small spindly tree depending on environment, and puts out lots of tiny leaves and fruits. Those fruits are about the size of a BB and a large individual could have over a thousand, not to mention upwards of ten thousand leaves (thankfully those also came in clusters for easier counting). Most species weren't as complicated to measure as pūkiawe (they were definitely on the more time-consuming end of the spectrum), but it'd still take around 4–6 hours to cover every plant.
As mentioned, this was our most frequent protocol, happening every single week. In our tropical climate we didn't see quite such dramatic changes over time as the mainland U.S. would with deciduous trees, but we could still see things like the ʻākala (Hawaiian raspberry) budding, flowering, and fruiting over the summer months.
Beetles (BET)
Happening every two weeks, beetles was another frequent protocol that ran almost the length of the season. We left three ground-fall traps at specific locations around six plots (for a total of eighteen traps) scattered across the Puʻu Makaʻala Natural Area Reserve (NAR), and every fortnight we'd collect the contents of those traps for sorting and identification of any beetles they contained. We were looking specifically for any species in the Carabidae family, a family of mostly-ground dwelling beetles with species around the globe (though the native Hawaiian species are arboreal, funnily enough). We found both native and invasive Carabidae species, with certain plots being known for the distribution either way, or for being the only plot that some species had been found at. While we didn't discover any new species this season, previous seasons turned up two entirely new species, so there are potentially more out there waiting to be found!
At the end of the season, after all the beetles had been identified, we started working on pointing them. Not “pinning” them, as they were too small for that (around 5–6 mm, on average), though the goal is the same: preservation for later viewing. The “det D. Berke” on the label in the photo above signifies that I identified this particular specimen (a common native species), which is pretty neat! We didn't manage to finished pointing all the beetles before us seasonal staff left, but we got through quite a lot of ~240 beetles – I personally pointed upwards of 70 over a few weeks. (I found it quite relaxing after a day out in the field when we had an hour or two left on the clock back at the office, like a miniature arts-and-crafts project.)
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| Beetles sorted out of a trap, ready for identification under the microscope. |
Mosquitoes (MOS)
- A team would go up in the afternoon to set ten mosquito traps at various location in the NAR. These had to be set within four hours of sunset, and would sit overnight.
- Another team would go up early the next morning and check all the traps for mosquitoes, taking any catches and resetting the traps. (This checking had to happen within four hours of dawn.)
- Yet another team would go up in the afternoon and check all the traps a second time after they had sat out during the day, then collect them and bring them and any catches down.
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| A mosquito trap. |
The protocol wasn't particularly difficult, but it did involve some of the more technical work we did, as we carefully calibrated CO₂ canisters to put off a stream of carbon dioxide to attract mosquitoes towards a little fan blowing into a canister. Most of the traps were located near roads (as in the photo the above), though there was one lovingly termed “the long walk” which took nearly 10 minutes to reach. (Which doesn't sound like much, until you're carrying a heavy CO₂ canister and the rest of the equipment down a muddy trail…)
We usually didn't catch a lot of mosquitoes, which was a good thing. Mosquitoes carry avian malaria, which is driving the extinction of multiple native Hawaiian bird species at lower elevations. Mosquitoes can only survive temperatures down a certain level, though, and at the height of Puʻu Makaʻala it's mostly too cold, so birds which can retreat to higher elevations are generally still safe. (Shorter islands, such as Kauaʻi, are watching their native bird populations die out in slow motion without being able to do much about it, as there simply isn't high enough elevation for the birds to retreat to as the atmosphere warms and the mosquito-free range shrinks.) On a typical bout we might catch 0–2 mosquitoes, and usually only in the lower-elevation traps. This is compared to places on the mainland where, with the same traps, they might catch hundreds or thousands of mosquitos – I remember watching a training video for this protocol, where the presenter up-ended a catch cup and a literal pile of mosquitoes several centimeters in height fell out. Thankfully, we didn't have to deal with that, and almost never had to worry about getting bitten during our time in the field.
Leaf Litter (LTR)
Another monthly protocol, this one involved collecting leaf litter from aerial ‘traps’ in the forest and separating it into various components. These traps were pretty simple, just some mesh suspended by PVC pipe – they didn't need to be complicated, just a standardized area to collect what fell from above.
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| Me, collecting leaf litter from a trap near the end of the season. |
Once the litter was collected into bags (from I believe 20 traps in different plots), we'd heat it to dry it out and then sort it into various functional groups. These were things like leaves, twigs, ‘woody’ (bits of bark), flowers, seeds, ‘other’ (for, e.g., lichen and other rare things that didn't fit other categories) and ‘mixed’, a catch-all term for leftover material. According to the protocol, each bag was only to be sorted for one hour maximum, at the end of which any remaining unsorted material would go into ‘mixed’. This was partly for mainland domains where the amount of leaf litter in fall could be overwhelming, but we found it useful as well when all the easily-identifiable stuff has been sorted out and what's left is just tiny detritus. (Sorting could also end early if the remaining unsorted material was no more than 10% of the mass of the sample, which was usually pretty easy to judge.)
While this litter was a monthly protocol, there was also another type of litter that happens just once a year, around September. This protocol (ground litter) involved gathering litter from areas demarcated on the ground which were larger than the aerial traps. While the monthly litter collection focused on small litter (sticks too large would be discarded), ground litter collection was something of the opposite, only interested in sticks and leaves (such as tree fern fronds) larger than a certain limit.
(While mosquitoes had “the long walk”, litter had the really long walk to get to some of the plots where collection happened, something like half an hour's hike along a fence pushing through ferns.)
Imageomics
There was one additional repeating activity we did, though this wasn't a normal NEON protocol; a number of people from different universities teamed up to use NEON's Research Support Services, where outside research groups can contract to get support from NEON personnel for their research. In our case, they set up a number of trail cameras and audio recorders around the NAR, with the goal of developing machine-learning systems to automatically identify native and endangered birds for better tracking. They set up the system in January of this year, and we mostly just swapped batteries and SD cards on a regular basis to keep things moving (plus uploading data from the cards, and the occasional bit of troubleshooting for cameras that weren't working). I believe they gave a presentation at a machine vision/machine learning conference last month so hopefully the project is going well, but I don't know too much about it otherwise. It was a fairly easy activity, though, and let me see some parts of the NAR that we normally otherwise wouldn't.
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| I saw these nēnē fairly close up in one of the areas we wouldn't normally be. |
I originally intended to talk about all the protocols in this post but even just the repeating ones turned out to be a fruitful subject. I'll have another post covering our non-periodic protocols soon where we'll wrap up by going over what my field season looked like. A hui hou!




















