Greg "Doc Lures" Vinall

Greg "Doc Lures" Vinall

Podcast Host, Lure Maker, Scientist, Educator

Greg is host of the Australian Lure Fishing Podcast. He’s an Aquatic Scientist, Lure Maker, Speaker and Author in the recreational fishing space. In this episode Greg looks for commonalities and trends in the information shared by his many guests on the ALF podcast regarding the best times to fish..

Fishing By The Barometer – Key Messages

  • A commonly believed fishing theory states that when the barometer is low, gasses in a fish’s swim bladder will expand, putting pressure on internal organs, making the fish uncomfortable and reducing the likelihood it will feed. Conversely, a high barometer is said compress swim bladder gasses, leading to the fish feeling hungrier and more likely to feed.
  • Despite almost universal acceptance of this theory, it doesn’t stand up to any kind of basic scientific scrutiny.
  • Due to water being 800 times denser than air, pressure on the swim bladder from normal movement of a fish vastly exceeds what can be exerted by atmospheric pressure. In fact, a fish swimming upwards by 1.5m to take a lure experiences swim bladder expansion greater than would be experienced by the fiercest of tropical lows associated with major cyclones. And fish can obviously make many such movements each day.
  • Barometric changes associated with approaching high or low pressure systems are very slow and fish can easily regulate swim bladder gasses to compensate for this. By contrast, pressure changes from waves or tides are much larger and happen much faster than storm fronts, yet they don’t alter fish feeding habits.
  • I suspect that barometric pressure does affect fish, but not in the simplistic ways most anglers think. As long as we beleive this common myth, we’re not looking deeper into something that could improve our fishing experience.


  1. Brett

    As a newbie fisho (only four landed catches to my name), I think it’s hilarious to see zero comments here. I think you touched on a real issue and explained it super well with good research! Thanks!
    I’m glad this myth has been debunked in my mind before I even really understood what the myth was.
    I was also super pleased to hear your podcast on night fishing… another big question in my mind.
    So it’s not just cos I’m the Donut King that I’m not catching anything at night. Your tips have given me hope that those cheeky sambos plopping every 10 seconds on the surface will take my lure if I present it in the right way.
    Maybe this week!

    • DocLuresFishing

      Glad you found my ramblings useful Brett! The trouble is, if we believe the myths because they’ve been around forever and because everyone else believes the myths too……. then we stop asking questions and trying to understand because we think we already know. It’s important not to just accept information as being fact (yes, even the info I share) and to always question. that way we get to all move forward.

      The question I want people to be asking themselves is “so if it’s not the swim bladder, then what is it?”. Eventually someone will come up with another theory – maybe it will be closer to the truth, or maybe not. But at least we’ll be working towards a better understanding, rather than running with a myth!

      Keep working on those sambos, eventually you’ll crack the code.



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