A decent catch and the River Khwai

April 7, 2016

At last, fish in our nets and no crocodiles!

Our tilapia catch at Xakanaxa, ready for processing. Fish were caught under research permits from the Ministry of Environment, Wildlife, and Tourism, and permission from Moremi Park.
Our tilapia catch at Xakanaxa, ready for processing. Fish were caught under research permits from the Ministry of Environment, Wildlife, and Tourism, and permission from Moremi Park.

We finally had a good catch near Xakanaxa – 15 tilapia and 14 other species.  The secret seems be going to the flood plains where the water is shallow (less than 1 meter) and there is lots of emergent vegetation – grasses and a variety of water lilies predominate.  The flood has come to Xakanaxa, evidenced by the low oxygen in the flood plains.  Low oxygen (3-4 mg/L) didn’t seem to deter the fish since they were there and they were obviously alive.

Map showing our sampling sites. Last week, we were at Xakanaxa and Khwai.
Map showing our sampling sites. Last week, we were at Xakanaxa and Khwai.
A lagoon surrounded by flood plains.
A lagoon surrounded by flood plains.

Our outdoor laboratory was busy all day.  It took until 5 pm to process all the fish and clean up.  Once the sun sets, the work day has to be done.

Our outdoor laboratory. We were fortunate to be able to work in this shelter. We added the blue tarp to hold back the wind.
Our outdoor laboratory. We were fortunate to be able to work in this shelter. We added the blue tarp to hold back the wind.

At 5 pm, my two colleagues went off to help a friend of theirs, leaving me alone at the boat launch.  Eyeing the bush around me suspiciously, I packed up the last of our supplies and samples.  A small group of plump birds fluttered around, engaged in a mating dance that made them oblivious of me.  Before dark, I walked back to the campsite, relieved to note that we had (human) neighbors for the night, who could keep me company from a distance while I wrestled the campfire back to life.

That night was just as exciting as all the others.  We cleverly put our pots away, so no clattering, but the hyenas came in to check out the camp just in case.  There was a loud sniffing at my tent zippers at one point, making them clink against each other.  A little unnerving, but the zippers were shut tight, and whatever it was moved on.  Lions roared in the distance, but unlike at Chief’s Island, this pride was far away.

In the morning, after saying hello to the elephant near the bathrooms, we packed up camp and headed out for one last round of water quality measures at our five sampling sites.  It was a glorious morning, sparkling, cool, fresh.  We worked through the sites, spotting red lechwe antelope at site 4 on the flood plain.

Wetland adapted red lechwe antelope in Moremi
Wetland adapted red lechwe antelope in Moremi

When we were as far away as possible, the boat engine died.

That’s right – it did not start at all.  Not a murmur, not a burp.  Just silence, leaving us staring at it and wondering what to do.  Well, we could stay there, dehydrating in the warming sun or we could do the aquatic equivalent of walking.  We could pole home.

In Botswana, people use long (3 meters or longer) wooden poles to push narrow canoes through shallow wetlands.  We carry two poles with us on the boat – mostly for pushing away from shore or getting ourselves unstuck if we accidentally beach the boat in too-shallow water.  Today we also had an extra-long piece of PVC pipe that we planned to use later for housing a data logger.  Three poles for three polers.

My colleague, R. Mothobi poling at the bow. There were three of us poling all together, and we moved at the grand speed of anywhere from 0-1 km per hour depending on the depth and degree of vegetation.
My colleague, R. Mothobi poling at the bow. There were three of us poling all together, and we moved at the grand speed of anywhere from 0-1 km per hour depending on the depth and degree of vegetation.

Off we went, at 1 km an hour for a nice 6 km ride.  It was fine at first because the slow pace gave me ample opportunity to really look at the water and the plants, to feel the variation in depth and substrate (river bottom) as we glided across the surface, to notice tiny fish hiding in the water lilies.  But after an hour, we were starting to tire and were looking forward with skepticism to the distance still to be crossed.

Moremi waterlilies
Moremi waterlilies

After 90 minutes, another boat showed up.  Thank goodness.  They were a nice burly boat with a big motor, carrying lumber to a wilderness camp.  They were exceedingly kind to give us a 20 minute tow back to our camp, effectively rescuing us from an all day, unplanned poling adventure.  “What an adventure,” said one of our rescuers, grinning at the sweat on our brows.

Rescue tow. We were grateful to see the last km fly by a bit faster.
Rescue tow. We were grateful to see the last km fly by a bit faster.

With our poling excursion behind us, we left Xakanaxa Camp and drove on to Khwai, where the parallel running river crosses the road.  It’s 42 km of sand track that takes at least two hours.  We took the “dry” route, so my colleague only had to wade once along the road to determine if the car could navigate the “puddle”.

Dry route from Xakanaxa to Khwai. In fairness, this was the deepest water we had to cross - and we did make it with trailer in tow.
Dry route from Xakanaxa to Khwai. In fairness, this was the deepest water we had to cross – and we did make it with trailer in tow.

Khwai is a small village, located a few km from Moremi North Gate, across an extra sketchy bridge.  We crossed this bridge once, pulling a trailer with a boat.

Moremi North Gate.
Moremi North Gate.
Elephant skull at Moremi, North Gate.
Elephant skull at Moremi, North Gate.
A sign before the Khwai bridge.
A sign before the Khwai bridge.
Bridge over the River Khwai.
Bridge over the River Khwai.

At the other side, we bought cokes at a shop that powered its fridges with solar power, and then we drove back again across the same sketchy bridge!  It held up both times and we had no disasters, so I am obviously way too picky about bridges.

Khwai Village shop with solar power for the fridges.
Khwai Village shop with solar power for the fridges.
River Khwai with remnants of the old bridge.
River Khwai with remnants of the old bridge.
Mothobi installing a conductivity/temperature data logger at Khwai.
Mothobi installing a conductivity/temperature data logger at Khwai.
A data logger for conductivity and temperature, records these parameters every 30 minutes for 200 days, and then we can download.
A data logger for conductivity and temperature, records these parameters every 30 minutes for 200 days, and then we can download.
Moss and I collecting a water sample from the Khwai bridge.
Moss and I collecting a water sample from the Khwai bridge.

It was 8 pm by the time we rolled back into Maun, having seen magnificent kudu, delicate impala, imposing buffalo, curious hornbills, and loads of zebra and giraffe along the way.  I was glad to get home and sleep in a soft bed.  I like the camping and the not camping.  At home, the only wildlife that wake me up in the night are mosquitoes.

Impala at Xakanaxa.
Impala at Xakanaxa.