7-22-23 Day 4: a rough day at site 11…

Today was the last day for the small mammal traps (3-day timeframe) in their current location, so in addition to checking the traps, we would have to collect them clean them, and bring them back to base camp.  So because the morning routine would take a little longer, instead of our planned area 9 hike (which is the hardest hike we will do), we instead switched to an less time-consuming area 11 hike (insert ominous music here…)

So the plan for today:

1. morning:  do day 3 of collecting traps, and then remove, clean, and bring them back to base camp (we will set them up in a new site for another 3-day stint of collection in a few days)
2. afternoon:  area 11, hike to the research sites and take tree growth, nest box measurements, collect tea bags for soil decomposition rates, and then grab SD cards from the cameras

The morning started out normal enough:  we got some amazing captures in the small mammal traps:

• we got a bank vole that had given birth IN THE TRAP!  The protocol is to take the normal measurements on the mom, and then put the babies near the capture site (a little hidden so predators cannot easily find them) in some cotton, and then release mom near them.  Mom will then come and grab each baby back to her den.  Here are pictures of her and the babies…

• Uri and Jana were also VERY excited because we were able to capture a water shrew (Neomys fodiens) – they have been trying to capture this threatened species (it requires very clean water for its habitat), and FOR THE FIRST TIME they caught one this morning!  Because it was the first one, they didn’t want to stress it out too much, so only Jana took pictures, they didn’t take any measurements, and then they released it.  She said if they caught one again, then they would do all the measurements.

Once we had checked all the traps, we collected them, cleaned them, and then had some lunch before heading out to site 11

Site 11

So, site 11, we had been told, was a pretty vertical up hike, and then we had the following tasks to do once at the data collection site:

• Tea bags/soil decomposition rates
• tree growth and nest box checking
• camera SD card collections

But before I describe all the perils of site 11, let me do this post’s science lesson, which is the rate of decomposition in the soil using tea bags.

In 2013 a paper came out by Keuskamp et al that was an ingenious way for ecologists to measure the decomposition rate inside the soil.  It could be done in any ecosystem, and was very inexpensive.  This method is known as the tea bag index, TBI.

When organic matter dies, the majority of it is actually not consumed by the next trophic level, but is often left in the environment (example when a lion eats an antelope, it won’t eat the bones, lots of hair is left behind, etc).  The parts of an animal or plant (bark, etc) that is not consumed and is left behind is called the detritus.  This detritus, while long dead (plant or animal), still has lots of energy left in carbon compounds, and these get broken down by the decomposers.

If the Earth is being constantly affected by global warming, then chemical reactions should be happening faster, including the chemical reactions the decomposers use to break down these carbon compounds of the detritus.  How do we measure this?  How can we measure this in different ecosystems?  The authors of this paper did the following, and showed it to be effective in any environment

1. they used Lipton tea bags (YES), two types:  green tea and rooibos (red) tea, which Lipton produces, and (of course) very accurately weighs into each tea bag

2.  You weigh the tea bags beforehand, label the tags, and then take them to the site of interest (in our case, each of the sites we are studying)

3.  you bury the tea bags, letting them undergo decomposition in the soil (decomposers are in there).  After a specified time period (the paper used 90 days), you dig them up, brush off the dirt, dry any moisture out of the oven, and weigh the bags.

So, what is happening here?  The tea inside is the detritus, that is, the dead organic matter.  The mesh of the bags are clearly small enough for microbial decomposers to get in there, but not animals, etc.  so if decomposers are doing their job, they will basically feed on the tea leaves, and the tea will weigh less after being buried for some time.  Here is the data from the paper:

So for each site, the scientists are interested in 3 time frames for the decomposition rates:  6 years, 3 years, and 3 months.  Each time frame has 5 sites/spots.  They are set up like this

Here are some pictures of us digging up tea bags (we were gathering the bags buried 3 months ago)

Okay, so site 11.  Well, it was terrible.  It was by far the hardest hiking we have had to do, and it was almost all off trail – I’m not sure I can describe how hard it was, climbing up into the forest, stepping on branches, falling into the divets underneath the bush or grass you are stepping on, trying to traverse rock flows, etc etc.  We were told it was steep, but “not too long.”  Ah hem.  We did the math, when we got to the rendezvous point for the data collection, we had scaled 1066 feet/mile.  WITH NO PATH.  To give a reference point for Oregonians, the Misery Ridge loop at Smith Rock is 630 feet/mile.  We had many falls, several people fell on the rock crossing, it was just….it was not great.  Yet, this site is part of the data set, and we can’t throw it out just because we didn’t like doing it.

Half of us stayed at the elevation of the rendezvous point and dug for tea bags and changed out SD cards from cameras.  The other half hiked up EVEN HIGHER and checked tree growth and nest boxes.  Here is some documentation

Me complaining about site 11…

Area 11 sucks…

Trying to show the angle of steepness (but Candace is also standing on an angle, so it is actually more severe

But still, some amazing scenery

I leave you with some quotes from the team about site 11:

Irene:  by far the hardest site, because of the off-trail incline we had to climb.  And for half of us, no reward view at the end

Candace:  I said no f-ing way

Mike:  insane, but fun

Karen:  a “bit challenging”

Kevin: (shaking his head) a big no

Kendi:  very very difficult terrain, exhausting, possibly dangerous

But don’t get me wrong:  we are loving every minute of this!!!!!