Monday, December 16, 2013

Building little rivers

We are planning to conduct an experiment in January using small, artificial stream channels. Scientists use these to experimentally manipulate rivers in a controlled way to understand causes and effects of river processes. They are often made out of metal or fiberglass, but these can be expensive and difficult to transport. Chris came up with the brilliant idea to make ours out of PVC canvas, so today we met with our favorite canvas guys at Savannah Africa Designs to see what they thought. They were excited about the challenge and should have a prototype ready by Thursday!

Thursday, December 12, 2013

The Sleepy Talek Rises

The Talek River is a pretty, lazy river.  The quality of the water in the Talek is a little "off" sometimes for a variety of reasons. makes for some great pictures.

If you're glued to our website (like I'm sure many of you are), you must have noticed that the Talek came up a bunch last night.  Here is data from our custom built automated data logger on the Talek.  It started texting us last evening at around 7PM to let us know the river was rising.  The river rose over 4 meters in 4 hours!

I'm still working out some of the bugs (some of the dropped values in the graph)...but it is nice to have live data. 

Wednesday, December 11, 2013

Gambling on the Rain

Over the last few years working in the Mara, Chris and I have noticed a very interesting pattern. After the river has been low for a while, the next big rainstorm will usually bring a flushing event that will result in a crash in dissolved oxygen and sometimes an associated fish kill. In general, we believe these events are due to the flushing of large amounts of carbon, and associated microbial activity, through the system. However, we are still testing several hypotheses about where exactly all this carbon comes from. It could be from the scouring of hippo pools along the main channel; it could be from the draining of several low-flow tributaries into the Mara; or it could be from some other source we haven't found yet. To test these hypotheses, it is important to capture water samples during both the rising and falling portion of the flush. Last year, we purchased some automated water samplers that can be set in advance and triggered to start sampling when the river rises to a certain level, in order to better study these events. 

As you may have seen from the falling depth gauge on the top right corner of our blog (or under the Mara Live link), the river has been steadily falling over the last month, and getting to very low levels. Last week we spoke with Brian Heath, Director of the Mara Conservancy, and he told us that big rains were going to start in the next week. Brian has lived in the Mara for 11 years and knows it incredibly well-- when he says something is going to happen, you should listen! So Chris and I headed down to the river last week and set up our automated sampling machine, gambling that the coming rains would bring about a large flushing event

Setting up our automated sampler in anticipation of the rains

Yesterday, we awoke in Narok to a text message sent from our real-time water quality meter that the river had risen 3 feet and the dissolved oxygen (DO) had crashed to below 20%! Hopeful that the automated sampler had worked as planned, we hopped in the car and headed back to the Mara, arriving just as the levels were beginning to return to normal.

Graph from the Mara River showing depth, DO and turbidity in response to a flushing event
Excitingly, we arrived just one hour after the sampling program had been completed, and everything worked! The sampler had triggered after the river rose about 6 inches, and had taken samples all through the rising and falling limb of the flood! Now we can analyze these samples to determine where the water came from that caused the event, how much hippo feces it was carrying, and how much microbial activity was occurring in the river. This translates into us having a lot of filtering to do!

Sunday, December 8, 2013

Lost and Found

October and November were rough months for us, in which we were hit with a series of challenges that really set us back a bit. Unfortunately, this resulted in us getting a bit behind on our blog updates. I thought I would just give a brief recap here of some of the things we lost, and found, in the last few months.

  • Four of the six probes on our expensive water quality meter that gives us real-time data on the Mara River. They were damaged when the meter got stuck in the river during high flows, and we're still uncertain how we'll be able to afford to repair them. It turns out insurance doesn't cover water damage for something that's supposed to go in the water.
  • My laptop computer, which was stolen out of my hotel room while I was attending a meeting in Narok. Fortunately, all of my data was backed up in multiple locations, but this took some time (and money) to recover from.
  • A reasonable portion of my lower lip when I was bitten on the face by a dog, just after returning to the Mara with my new laptop. Hilariously, I had just been teaching Geemi the meaning of the slang word “bummer.” A flight to Nairobi, several hours of reconstructive surgery, five days in the hospital, and two weeks on a liquid/puree diet later, and I'm healing really well, thanks to the help of lots of wonderful friends and an amazing doctor.
  • Even more motivation for Chris to keep working on developing these amazing, low-cost, home-made water quality and quantity meters he has been building. They are relatively inexpensive and easily built, repaired and tweaked in the field. This kind of low-cost technology is really the key to revolutionizing water resources management in developing countries, where expensive parts and repairs aren't feasible.
  • A deep appreciation for my mother instilling in me the importance of backing everything up in multiple locations, and for my husband actually helping me do it. Also a deep appreciation for how fortunate we are to be able to usually shop for electronics in the US, where selection and price are hard to beat.
  • A profound realization of 1) the importance of good friends, who were ultimately the ones responsible for getting me into the hands of the best facial plastic surgeon in Kenya within 3.5 hours of the attack; 2) the incredible medical personnel and facilities available in Nairobi, where I had wonderful nurses and doctors taking great care of me; and 3) how lucky we are to be happy and healthy and able to do the work we love.
I have to admit this series of events left me feeling a bit vulnerable to all the dangers and challenges that surround and await us, but it also ultimately made me feel very blessed to be as fortunate as we have been... and maybe a little more wary of dogs. 

Anyway, we've been back in the field the last few weeks, busily trying to catch up from some of our unexpected delays, so we have lots to post about in the upcoming weeks. Fish sampling, leopards in camp, nutrient chemistry, and gambling on a DO crash... stay tuned!

Sunday, December 1, 2013

Baby bat

Processing samples late into the night... As a baby bat sits on our tent watching us...