The hula hoops and the chicken wire give the drifter shape.

Early this week, I built a drifter. 

The drifter is a big contraption that hangs from an small buoy and drifts along with the current. It allows me to track the flow of the water.  It is really easy to make the drifter. I build it using hula hoops, chicken wire, blue tarp and plastic ties.  The hula hoops act like a skeleton, giving the drifter shape. The chicken wire is also like a skeleton and the tarp is like a skin. There are some holes so that the water can run through the drogue instead of around it. That way, the water gets stuck in the drifter and the drifter gets stuck in the water, and they both move along together with the current.  So sometimes we use fancy equipment on research expeditions, and sometimes we do science with simple things that we just buy at the store.  

The tarp gives the drifter lots of surface area so it can move along with the water. The holes help the drifter catch the water.