Download Lecture1_2008_Definitions&Anatomy

Welcome to
Ecology of Fishes Laboratory
Zoology 511
What is a Fish?
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Poikilothermic – body temperature is identical to surrounding water
Chordates – have developmental characteristics of all vertebrates
Appendages developed as fins
Chief respiratory organs are gills
Body generally covered with scales
“A fish is an aquatic vertebrate with gills and with limbs in the shape of
fins” (Nelson 1994)
There are over 25,000 fish species, so there are exceptions to these
general characteristics.
Fish vs. Fishes
“This tank is full of fish.”
“The ocean is full of fishes.”
How fish are named
Pomaxis annularis
Black crappie…or…
speckled perch, specks, papermouth,
bachelor perch, calico bass, strawberry
bass, or white perch.
White Perch,
Morone americana
Fish Ecology….?
Ecology is the study of the distribution and
abundance of living organisms and how their
distribution and abundance are affected by
interactions between organisms and their
environment (Krebs).
An extensive subject…
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In my analysis, the spectrum ranges from ichthyology (evolution, taxonomy,
structure and function, and biogeography of fishes); fish biology
(metabolism, energetics, tolerances sensory process, behavior,
reproduction, age/growth principles, demography, etc.); fish ecology
(generally relating fish to their biotic environment at the individual,
population, community and ecosystem levels); fish assessment (I say fish,
instead of fishery, because we sometimes need to assess non exploited
populations) that includes sampling methods tagging, analysis of sampled
data (e.g. population size or structure); fishery resources (global and
regional fisheries and their economic, sociological values (commercial and
recreational), gears, markets, etc.; and finally fishery management (how to
analyze fisheries (stock assessment, modeling, etc) and apply everything
else to manage exploited or protected resources). PHEWWW!
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An Excerpt from an email of Dr. Randy Edwards
Some definitions of terms you’ll hear
Ichthyology: (Fish biology) is the branch of zoology devoted to the study
of fish.
Fishery: A fishery (plural: fisheries) is an organized effort by humans to
catch fish or other aquatic species, an activity known as fishing.
Fisheries Management: The effort to regulate where, when and how
people fish, and how many fish they catch, to protect fish populations
so that people can continue to fish.
Fisheries Science: Think of fisheries science as all the math behind
fisheries management. That is, how do you make informed decisions
on how to regulate people to protect fish populations?
All of these are incorporated into fish ecology and
fish ecology plays an important role in all of the
above!
Anatomical terminology of a fish…
Dorsal
Anterior
Posterior or
caudal
Lateral
Ventral
Used for relating different parts….Eye is posterior to the mouth
Conversely the mouth is anterior to the eye
Lateral
Fins of a fish…
Dorsal
Caudal
Pectoral
Anal
Pelvic
Adipose
Pelvic
Pectoral
Bowfin (Amia calva)
Bowfin (Amia calva)
Dorsal
Giant snakehead
Fins spines vs. rays
Bluegill
Black Crappie
Heterocercal Protocercal
Homocercal Diphycercal
Fish Scale Types
Most bony fishes (Teleosts)
Overlapping = Flexibility!
Fish Scale Types
Bowfin, paddlefish,
gar, sturgeon
Shark teeth and spiny tail on rays =
modified placoids
Sharks and rays
“riblets” decrease drag. Nanotechnology
Scutes are a
modification of
scales
Mouth placement
superior
terminal
vs.
inferior
Premaxilla
Maxilla
Internal anatomy – the basics that help
understand the ecology!
Stomach
Swim bladder
Liver
Heart
Intestine
Ovary
Fat deposits
Gills and Gill Rakers
Gill filaments
Gill arch
Gill rakers
Ecology influences anatomy
Muskie
Northern Pike
Chinook Salmon
FISH WITH TEETH
Burbot
Not all
Teeth
are
pointy!
Longfinned
Eel
Walleye
vomerine
teeth
Barbels: nothing is easier to identify!!
Yellow Bullhead
Brown Bullhead
Burbot
Burbot
Oddballs: Rostrum
Measure anatomy to do ecological studies
Enough lecture, lets look at
some fish