Studying Aquatic Life at the World's 2nd Largest Lake

Lake Victoria is HUGE, more like a small sea than a lake. You'd think it would be a great location for  teaching kids marine biology, right? Not so much.

I was reflecting on this irony as I planned for this semester's science. Last semester, when we studied birds, we were able to take advantage of East Africa's rich variety of birds to bring our classroom studies to life. And here we are, right next to this huge lake... surely we can at least comb the beach for tide pools?

The problem is that Lake Victoria (along with most other East African lakes) is home to the bilharzia parasite. Contracting bilharzia is a pretty nasty experience, so I'm told. So we won't even get our feet wet. Sigh.

But perhaps we can do so figuratively? The textbook we're using is no help sometimes. We just finished our chapter on fish, and it suggests experimenting with the affects of water temperature on pet goldfish. We have a lake full of tilapia, nile perch, and a bunch of other things, but we have no pet store that sells aquarium fish. Plus, I'm slightly disturbed by the idea of intentionally messing with live fish.

However, I have no problem messing with an already dead fish! If we can't do the recommended activity, let's introduce the classic biology project: dissection!

We had already been intrigued by certain aspects of fish anatomy (Did you know they have nostrils? Four of them?), so even my more skeptical students were willing to give the idea a chance.

Now is when our proximity to the lake finally pays off: it is super easy to get a fish. The day before I wanted it, I asked my gardener to purchase a sizable fish first thing in the morning. He stopped by a fishermen's landing spot (not far from my house) and brought me a nice fresh nile perch--for about $4.

Love Ellie's face (on left, pink headband)

Just to be clear, I know nothing about fish. I last dissected one in high school. So I'm very thankful for the internet and the nice guide full of photos that I found. With that help we were able to identify the major organs.

"And there's the heart..."

We were especially interested in the swim bladder--this "balloon" we'd read about that enables the fish to control its depth in the water. I was very pleased to find the thing intact, still inflated. We successfully floated it in a tub of water; believe me this is very cool.

Throughout the operation, I made sure the kids knew they could take a break. I remember feeling squeamish about this stuff! In fact, I gave them the same option I took when my cat was being cut open on this very table--escape to the nearby living room furniture. All the kids were interested to see the various parts of the fish, but some appreciated my warnings of, "I'm going to try to take this out now," and they'd retreat. Towards the end it was sometimes just me and the boys. :)

But they always came back to see each new discovery! I'm very proud of them.

Besides, at their age pronouncements like, "This is the grossest thing we've ever done!" are very positive! (And I heard that several times.) I bet they'll remember how fish breathe through their gills, too.

Meanwhile, my educational experience continues: I'm going to try to learn some easy ways to cook fish!