Color In Fishes

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Color In Fishes

• Presented by Matt Beam

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• Color is an extremely important aspect
• of the world we live in. Fishes use color
• in a variety of ways
• To avoid predators
• To sneak up on prey
• To attract mates
• To communicate

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Topics

• The production of color
• -chromatophores (color cells)
• Color change
• -mechanics and control
• Functions of color
• -concealment, confusion, communication,
  and
• advertisement

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Structure of Color in Fish Cells

• Usually color cells are in the skin
• Color cells chromatophores
• 2 Types of chromatophores
• Biochomes (pigment)
• Schematochromes (structural)

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Biochromes

• Chromatophores with pigment
• Chemical absorption
• Reflected wavelengths give color

DevoBio
(Pigment cells in the dermis)
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Schematochromes

• Chromatophores without pigment/color
• Crystaline
• Prism-like
• Color produced by relection
• Counter-shading

www.angelsplus.com/ genetics.htm
(Example of iridophores on a Koi angelfish)
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Color Change

• 2 different kinds of color change
• Short-term (physiological/neural)
• Long-term (morphological)

Image J. Kimball
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Short-term Color Change

• Movement of pigments in cell
• Contractile muscle around chromatophore
• Physiological Change
• -Hormones
• Neurological Change
• -Neurohumors

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Physiological Change is a Response to Stimuli

• Occurs from a few seconds to hours
• Change in background color
• Behavioral
• Social
• Chemical

(longfin sculpin)
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Long-term Color Change (Morphological)

• Change in pigment concentration or type over time
  

Images www.clarku.edu/departments/biology
Juvenile Damselfish
Adult Damselfish
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Triggers for Morphological Color Change

• Diet changes
• Developemental
• stages
• Migration / change
• in salinity

www.alaskaseafood.org
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Functions of Color

• Concealment
• Confusion
• Disguise
• Advertisement

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Concealment

• Countershading
• Cloaking of food
• Matching color to environment
• -bottom coloration
• -Plant-like patterns
• -open water

http//aged.ces.uga.edu
(Bowfin)
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(Sculpin) -Bottom coloration
(Needle fish)
Mustard
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Confusion (Disruptive Coloration)

• Stripes
• Bars
• Ocelli

www.aquarist-classifieds.co.uk/ gallery/Marine...
(Butterfly fish)
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(French angelfish)
Google Images
(Painted Greenling)
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Color for Disguise

• Mimicry of plants
• -color, special appendages, posture
• Mimicry of other fish
• -batesian
• -aggressive
• -lures

(Mosshead Warbonnet)
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Jacks aggressive mimicry
Trumpetfish plant mimicry
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David Worbel
(Striped anglerfish)
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Color as Advertisement

• In finding a mate
• Species recognition (schooling)
• Of mood (defending nest, etc)
• Of bad taste or poison

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Chris Newbert
(Three-spined stickleback)
(Mating mandarin fish)
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James Montgomery
(Lionfish)
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• Color is extremely important for fishes
• Chromatophores
• fishes have several strategies to use color
• capturing prey, avoiding predators, reproductive
  success, and communication