How to Collect Fish Guts for Science

How to Collect Fish Guts for Science

We are collecting cod and salmon guts this season (2017) in Newfoundland and Labrador to see what they’re eating, and specifically to look for plastics. If you fish, we’d love to have your guts! What we need from you: A bag of guts (from the mouth to the anus) and a corresponding information sheet (per fish). What we’ll do: pick up or arrange pick up of the guts, and post whether your particular fish had eaten plastics. Findings from your fish guts will be used to write scientific papers, inform policy makers, and propose plans for plastic pollution control in Newfoundland.

You can record information about your fish on the form linked here, or simply use it as a guide to what your information sheet should look like (the information we need is explained below).  Please use a sealed, leak-proof plastic bag for your guts (like a ziplock or a plastic bag tied off at the end) and make sure that both the bag and the sheet are labelled to match each other.

Prior to filleting/gutting:

  • Record the location from which the fish was caught on the form/paper

Your local body of water. i.e. “Petty Harbour”, “Brigus South”

  • Provide the fish with a unique name or identifier on the form/paper

i.e. “MobyDick1964”, “Bob007”, “PH123”. We’ll post the results under this name!

Write this in permanent ink on both the bag (prior to filling it or getting it wet) and the information sheet. This helps us keep the right information with the right guts and will also allow you to track the results once they become available and find out if your fish has ingested plastic.

Results will be posted at once the data has been processed (likely 2-5 months). Contact Jessica Melvin if you want to check in on your results (

  • Record the length of the fish;

Measure the length from the tip of the snout to the end of the spine, or the end of the body excluding the caudal fin – shown as “standard length” in the figure below. So just the flesh of the fish. Measurements should be taken in cm or inches.


fish length


For our plastic ingestion analysis we require the entire digestive system (the stomach as well as its attached tubes/intestines) from mouth to anus – as shown in green in the figure below. Plastics can be in any part of the food tract.

guts diagram

When removing the guts it is useful to grasp the intestine as close to the anus as possible to ensure this portion of the intestine is not lost. If the intestines (or stomach) are cut or split apart, unfortunately we cannot use them. Once ruptured, the guts can be contaminated by plastics and fibres during transport and storage and can result in bad results.

  • Freeze guts for pickup.

Contact the project leads to pick up guts:

Jessica Melvin:    709-986-5760
Dr. Max Liboiron: