Ask the Biologist

This information never gets old !

Originally published in the May/June Release Journal 2012.

Steve Kerr – MNR Biologist

Steve Kerr is a senior fisheries biologist with Fisheries Policy Section of the Ontario Ministry of Natural Resources. He has worked as a biologist at various locations in the province for more than 35 years. Steve has had a long involvement in cooperative projects with Muskies Canada and has published several papers on muskellunge. In 2010 he was inducted into the Muskies Canada Hall of Fame.


Do vertical holds really harm a muskellunge or is this a myth?

Amazingly, there have been few, if any, well designed scientific experiments which have examined this issue. The consensus amongst numerous experts (Butler 2004, Ramsell 2004, Landsman and Thorpe 2008), however, is that vertical holds should be avoided.

The body of a muskellunge is supported by water under normal conditions. When out of the water, large fish need to have their body supported. Vertical holds can lead to a number of problems including:

  • separation of the vertebrae
  • injuries to soft body tissues
  • damage to the operculum and connective tissues in the head and gills
  • organ displacement or damage
  • internal haemorrhaging
  • stretched or torn muscles

If necessary to remove a large fish from the water, do it quickly in a horizontal position and support the fish’s body mass with one hand or arm positioned near the mid section of the fish.

Instead of vertical weight measurements, muskellunge anglers should lift the fish (preferably in a cradle or knotless net) and weigh the fish while having its weight supported by the net.

Note: You can also use a weight calculator – based on length and girth.

What are some of the most important things to remember for a successful release?

There are several key factors to keep in mind:

      • quickly play and land the fish
      • remove hooks quickly
      • keep fish in the water as much as possible
      • do not touch the fish’s gills
      • use a horizontal hold (supporting the fish’s body mass) for photos
      • minimize the amount of air exposure
      • spend as much time as required to revive a fish

Does catch-and-release angling work?

Absolutely. There is considerable evidence to indicate that the quality of Ontario’s muskellunge fisheries is due to protective size limit regulations and an increase in catchand-release angling practices.


Butler, M. 2004. Vertical holds of larger fish: not the best choice for catch and release. Muskie May:4-7.

Landsman, S. and M. Thorpe. 2008. Blending science and proper handling practices for a better release. Muskie. October:15-17.

Ontario Ministry of Natural Resources and Muskies Canada Inc. 1999. Effective release techniques for muskellunge. Queen’s Printer for Ontario. 7 p. Ramsell, R. 2004. Muskie handling techniques to improve the chances of survival for your released catch