Editing Swim bladder (section)

==Sonar reflectivity==
The swim bladder of a fish can strongly reflect sound of an appropriate frequency. Strong reflection happens if the frequency is tuned to the volume resonance of the swim bladder. This can be calculated by knowing a number of properties of the fish, notably the volume of the swim bladder, although the well-accepted method for doing so<ref name="Love_1978">{{cite journal|last1=Love R. H. |title=Resonant acoustic scattering by swimbladder-bearing fish|journal= J. Acoust. Soc. Am.|year=1978 |volume=64 |issue=2|pages=571–580 |doi=10.1121/1.382009|bibcode=1978ASAJ...64..571L}}</ref> requires correction factors for gas-bearing zooplankton where the radius of the swim bladder is less than about 5 cm.<ref name="Baik_2013">{{cite journal|last1=Baik K. |title=Comment on "Resonant acoustic scattering by swimbladder-bearing fish" [J. Acoust. Soc. Am. 64, 571–580 (1978)] (L)|journal= J. Acoust. Soc. Am.|year=2013 |volume=133 |issue=1|pages=5–8 |doi=10.1121/1.4770261|pmid=23297876|bibcode=2013ASAJ..133....5B}}</ref> This is important, since sonar scattering is used to estimate the biomass of commercially- and environmentally-important fish species.