Frog Trawl




About: Empowering citizen scientists to track and together prevent marine pollution.

We will show you how to make a frog shaped bridge trawl using $15 materials from IKEA and other hardware stores.

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Step 1: Materials

Here are materials you will need

1. Krokig (Wall storage with hooks): IKEA, $4.99

2. Rope 3.9mm: Home Depot, $2.98

3. Binder Clips small: Staples, $3.79

4. Mesh Wash Bag (Large): Home Depot, $3.79

5. Recycled water bottle (2 bottles)

Step 2: Place the Wash Bag Inside the Mouth of the Krokig

Put the wash bag in a smaller hole of the krokig and leave the mouth opened.

Step 3: Clip the Wash Bag to the Krokig in All Sides

Using the clips, fix the wash bag on the krokig. You can check the bag if it's fixed well by pull out.

Step 4:

It should look like this, now let's put weight on to it

Step 5: With the Rope, Tie a Knot

Tie a knot on to each side of the krokig with a rope.

Step 6: Tie the Other End of the Rope to a Recycled Bottle

Tie the other end of the rope to a recycled bottle, do it for both sides
Note: Put rocks and pebbles in each water bottle so that krokig can be half submerged in the water

Step 7: Tie the Rope on the Top Two Sides and You’re Done!

Tie the rope on the top two sides and you're ready to trawl!!

We first tested this trawl in Spring of 2017 and it performed very well.

Step 8: Process Samples

Check out how to process the samples collected.



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    2 Discussions


    Reply 2 years ago

    Hey, a trawl is usually a a large wide-mouthed fishing net dragged by a vessel along the bottom or in the midwater of the sea or a lake. We are redesigning it to skim the surface of the water for plastics!