TAKEOFF
BASS SCIENCE
ALL ABOUT GILLS
HOW THEY WORK AND HOW TO PROTECT THEM
By TJ Maglio
ILLustRAtIoNs by kevIN hANd
everyone knows that virtually all fish , bass included , “ breathe ” with the aid of gills rather than lungs . In addition to fish , many amphibians , mollusks and crustaceans also use gills to get the oxygen they need to survive .
Although most anglers certainly know bass have gills , it ’ s a good bet far fewer know anything about how they work . Here ’ s a look at the form and function of gills and how to protect them so fish can be released unharmed .
Why gills ?
Human lungs draw oxygen out of the air and remove carbon dioxide through gas exchange across a matrix of microscopic air sacs called alveoli . The diaphragm inflates and deflates the lungs as we breathe .
Water is approximately 777 times denser than air and contains only a fraction of the oxygen . If your lungs had to “ breathe ” water , your diaphragm wouldn ’ t be nearly strong enough to inflate or deflate , and your alveoli couldn ’ t produce nearly enough oxygen to sustain life .
Given the difficulty of breathing in water , fish evolved gills , which contain thousands of filaments connected to a vast network of blood-rich capillaries .
gills at Work gill filaments
This provides a large surface area for extracting oxygen from the water and secreting carbon dioxide .
how they Work
Most freshwater fish have three pairs of gills aligned on each side of their throat . The gill filaments are attached to the bony gill arches and covered by the operculum , which is the plate-like structure along the side of a fish ’ s head .
Bass “ inhale ” by contracting their throats to draw water in through their mouths , and then “ exhale ” by opening the operculum to allow the water to escape out the gill slits .
lamella plates
1 . Water comes in the mouth . 2 . As the water moves across the gills , oxygen
diffuses into the capillary network running through the lamella plates , which are substructures of the gill filaments that provide additional surface area for absorbing oxygen .
3 . Carbon dioxide and other waste products diffuse back into the water .
protecting gills
In addition to carefully handling bass to avoid physical trauma to the gills and other organs , there are several ways to ensure you ’ re protecting bass gills when fishing .
Keep them in the water – Gill tissues will be damaged by prolonged exposure to air . Release fish quickly , and try to minimize their exposure to air when culling or while at the weigh-in stand .
Don ’ t touch them – Try to avoid “ gilling ,” or lifting bass by the gill plates . This can seriously damage the gill tissue .
Don ’ t use peroxide – Some anglers still believe that adding hydrogen peroxide to livewell water can increase dissolved oxygen . It can ’ t , and it actually causes damage to sensitive gill tissue . Stick with cool water and approved livewell treatments .
Unhook fish quickly and carefully – This goes without saying , but ripping a hook through gills can severely damage them , so make every effort to unhook deeply hooked fish quickly and cleanly . Keep a quality needle-nose plier handy , and if possible unhook bass in a landing net that ’ s submerged . When a bass is hooked in its gills , consider working the hook loose from behind the gill plate , rather than through the mouth . This is often the best way to remove it without causing excess damage .
22 flWfIshIng . Com I november-deCember 2017