Make your own tools for collecting aquatic invertebrates without harming them.
We wanted to collect samples of aquatic invertebrates to identify the populations and gain insights into the quality of the sampled water. We did not want to harm the invertebrates and we were concerned that many collection methods would do harm to the little creatures we were studying.
I developed a tool that collects many invertebrates, with exception of the largest, without harm. I call these "Sucker-Uppers" because that is what they do, suck up the invertebrates without harm so they can be identified, counted and returned to the water they came from.
- 3/8 to 1/2 inch clear plastic tubing
- 20 ml pipette bulb
- silicone adhesive
Step 1: Forming the Plastic Tube
The clear plastic tube typically comes in 36" lengths.
Direct a hot air gun at 3 to 4 inches from the end of the tube. Once the tube becomes flexible with the heat ,stretch the tube. As it stretches, it will become narrower and thinner.
Immediately immerse the hot tube in cold water. MAKE SURE THE HOT AIR GUN IS NOT NEAR THE WATER. The cold water will cool and solidify the tube.
Step 2: Cutting the Tube
Once the stretched tube is rigid, cut in the middle of the stretched zone. This will give an eye-dropper shape with an opening around a 1/4 inch.
Step 3: Attach the Pipette Bulb
Once a section of plastic tubing has been shaped and cut to a length of about 4 inches, it is time to connect the pipette bulb. This bulb will allow you to suck up most invertebrates.
Put a small amount of silicone adhesive on the large end of the plastic tube, then twist the bulb onto the plastic tube. Let this set until the silicone hardens.
Step 4: Using a Sucker-Upper
Using the sucker-upper is fairly simple. Just squeeze the bulb, place the tube opening in front of the invertebrate you are picking up, release the bulb and the "bug" is sucked into the clear tube.
Don't tip it upside down, the bug will fall into the bulb and be difficult to get out.
Hold the sucker-upper, bulb up, and look at the invertebrate. The shape of the clear tube, magnifies the "bug" and aids in identification.