View source for Biology:Fish measurement

{{Short description|Measuring of individual fish and various parts of their anatomies}}
'''Fish measurement''' is the measuring of individual fish and various parts of [[Biology:Fish anatomy|their anatomies]], for data used in many areas of [[Biology:Ichthyology|ichthyology]], including [[Biology:Taxonomy|taxonomy]] and fishery biology.

==Overall length==
{{anchor|Standard length}}'''Standard length''' ('''SL''') is the length of a fish measured from the tip of the snout to the posterior end of the last vertebra or to the posterior end of the midlateral portion of the hypural plate. This measurement excludes the length of the caudal (tail) fin.<ref>{{cite web | title=Term: standard length | work = FishBase.org | url = http://www.fishbase.org/Glossary/Glossary.php?q=standard+length&sc=is | date = 2004-11-18 | access-date = 2015-08-18 }}</ref>

[[File:Fish length.jpg|thumb|Total and fork length of a fish]]
{{anchor|Total length}}'''Total length''' ('''TL''') is the length of a fish measured from the tip of the snout to the tip of the longer lobe of the caudal fin, usually measured with the lobes compressed along the midline. It is a straight-line measure, not measured over the curve of the body.<ref name="tl">{{cite web | title=Term: total length | work = FishBase.org | url = http://www.fishbase.org/Glossary/Glossary.php?q=total+length&sc=is | date = 2004-11-18 | access-date = 2015-08-18 }}</ref>

Standard length measurements are used with Teleostei (most [[Biology:Actinopterygii|bony fish]]), while total length measurements are used with Myxini ([[Biology:Hagfish|hagfish]]), Petromyzontiformes ([[Biology:Lamprey|lamprey]]s) and usually [[Biology:Elasmobranchii|Elasmobranchii]] ([[Biology:Shark|shark]]s and [[Biology:Batoidea|rays]]), as well as some other fishes.<ref name="tl" />

Total length measurements are used in slot limit and minimum landing size regulations.

Fishery biologists often use a third measure in fishes with forked tails, called {{anchor|Fork length}}'''Fork length''' ('''FL'''), the length of a fish measured from the tip of the snout to the end of the middle caudal fin rays, and is used in fishes in which it is difficult to tell where the vertebral column ends.<ref>{{cite web | title=Term: fork length | work = FishBase.org | url = http://www.fishbase.org/Glossary/Glossary.php?q=fork+length&language=english&sc=is | date = 2004-11-18 | access-date = 2015-08-18 }}</ref>

==Fin lengths and eye diameter==
Other possible measurements include the lengths of various fins, the lengths of fin bases and the diameter of the eye.<ref>{{cite web | url = http://www.flmnh.ufl.edu/fish/Education/Diagrams/FishDimensions.html | title = Standard Measurements of Bony Fish diagram | publisher = Florida Museum of Natural History Ichthyology Department | access-date = 2007-06-06 }}</ref>

[[File:Grenadier basic external features.png|thumb|600px|left|{{center|[[Biology:Abyssal grenadier|Abyssal grenadier]]}}]]

{{clear}}

<gallery widths=180>
File:Black Drum Length vs. Age.png|{{center|[[Biology:Black drum|Black drum]]}}
File:Red Snapper Length vs Age.png|{{center|Red snapper}}

</gallery>

==See also==
*Ichthyology terms
* [[Biology:Standard weight in fish|Standard weight in fish]]

==References==
{{reflist|30em}}

==External links==
*[http://www.flmnh.ufl.edu/fish/Education/Diagrams/FishDimensions.html Diagram of fish measurements] - Florida Museum of Natural History Ichthyology Department


{{DEFAULTSORT:Fish Measurement}}
[[Category:Ichthyology]]
[[Category:Fish anatomy]]

{{Sourceattribution|Fish measurement}}