After spending two great weeks with us, David had to return to the US, but we had one more week in the field with Emma. During this time, we spent some more time investigating the Talek River and its tributaries. A lot of Emma's research is focused on understanding the impact of humans on river ecosystems, and she is working with us to untangle the role of urban developments vs. tourism facilities vs. hippo inputs in the Talek River and its tributaries. This is an important river system to understand because it is the main tributary in the middle reaches of the Mara, and it enters the Mara River in the middle of the reserve. However, water quality in the Talek can be very poor, which may have a big impact on the water quality we see in the downstream portion of the Mara.
|Build-up of rotting hippo feces and in a tributary of the Talek|
As one tool in our toolbox, we worked on a new method that can be used to detect something called "optical brighteners" in river water. I had never heard of optical brighteners until recently, but they are in many kinds of laundry detergent, and are what make your clothes look "whiter and brighter." It's not that optical brighteners are necessarily bad for the river, but if they are detectable in a river, they indicate the presence of large human inputs of other kinds, like nutrients and sewage.
|Emma and Chris collecting water samples in the Ntiaktiak River|
Sure enough, we did find optical brighteners present at certain sites in the river, but not necessarily where we expected them. This is an exciting new tool to have, but as usual with new methods, it only raised more questions for us.
|Emma testing for optical brighteners|
|Collecting hippo feces from hippo pool surveys|
|Amanda and Emma at the Mara Serena airstrip|