Fish Behavior
Behavioral ecology
•  Animals behave in ways that maximize their
fitness
–  Reproductive behavior = more successful
offspring
–  Feeding behavior = maximum energy gain
Game Theory
•  Tit for tat
•  Chess
•  Monopoly
•  Rock - Paper - Scissors
Animal Behavior
•  Action or re-action to stimuli
•  Happens in the brain (non-motor) and can be
manifested through muscular response, but often
involves both
•  There can be a temporal component to the actual
behavior (learning)
•  Short-term trigger for behavior, or effect on the
organism
•  Long-term evolutionary significance/adaptation:
behavior is selected for. •  Animals behave in ways that maximize their
fitness
Genetic vs environmental factors
•  Nature/nurture? On-going debate
•  Behaviors have phenotypic variation: studies
on problem solving
•  Due in part to genetic propensity: ‘ability’ to
learn
•  Due in part to environmental pressures and
variability
•  The two: genes and environment, work in
concert
•  Innate behavior: less subject to environmental
variation. Developmentally fixed
Genetic and environmental components of
behavior: a case study
Okinawa rubble goby
Trimma okinawae Bi-directional sex-change
Fixed Action Patterns
Fixed Action Patterns: stereotypical innate
behavior. The organism will carry it out
almost no matter what, even if it doesn’t
seem appropriate. These are all part of a
category of behaviors very important to
survival and/or fitness.
Fixed Action Patterns
Male three spined stickleback: attacks other
males with red bellies – attacks anything red
Three-spined stickleback
Gasterosteus aculeatus
Innate behavior
•  Brood parasitism is a classical example (Cichlid/
catfish)
Ability to confront novel stimuli, learn about them
and adjust behavior is indicative of intelligence
and self awareness. Intelligence is ‘costly’: brain
development, parental investment etc.
Haplochromis nubilus
Synodontis punctatus
Learning
•  Change in behavior based on experience
–  Maturation is behavior change based largely on
ability due to development (eg. Use of tool)
•  Habituation
–  Loss of responsiveness due to repetition
•  Imprinting
–  Learning in a critical time period (tightly correlated
with innate behavior) (e.g. bluehead wrasse young
females)
•  Conditioning: Pavlov
–  Associating a stimulus with punishment or reward
(can also be trial and error) (visual experiments)
Use of a rock as an anvil
Coyer, 1995
Halichoeres garnoti
Yellowhead wrasse
Learning
•  Change in behavior based on experience
–  Maturation is behavior change based largely on ability due to
development (eg. Use of tool)
•  Habituation
–  Loss of responsiveness due to repetition
•  Imprinting
–  Learning in a critical time period (tightly correlated with
innate behavior) (e.g. bluehead wrasse young females)
•  Conditioning: Pavlov
–  Associating a stimulus with punishment or reward (can also be
trial and error) (visual experiments)
Associative learning/conditioning
•  Associating one stimulus with another
•  Pavlov: classical conditioning.
Associating an arbitrary stimulus with
reward or punishment
Cognition
•  Problem solving studies
•  Consciousness and awareness
•  The connection between nervous system
function and behavior
•  Spatial orientation and mapping
–  Migration: Piloting, orientation (directional
headings), navigation (relative location)
–  The role of learning in migration
Migration
Migration
•  Spatial orientation and mapping
– Migration: Piloting, orientation
(directional headings), navigation
(relative location)
– The role of learning in migration
– (magnetite, light, etc..)
Temporal Migration
Spawning migration
Migration ladder
Pit Tagging
Superglue!
Scanning Tagging Great White Sharks
http://topp.org/features/fab_flight_white_shark
A white shark tagged with both acoustic (front) and pop-up satellite (rear) tags.
The acoustic tag is detected when the shark swims within 250 m of a listening
station, while the pop-up satellite tag records information about location,
temperature and depth – and relays it to the laboratory when the tag releases
itself from the shark.
Reproductive behavior
•  Sexual selection
– Courtship
– Female choice
– Male aggression
•  Leks
male
Pseudotropheus zebra
Lake Malawi
female
Mating strategies
•  Promiscuous
•  Monogamous
•  Polygamous: polygynous, polyandrous
•  Certainty of paternity matters!
Hexagrammos decagrammus
Kelp Greenling
Multiple paternity
Embiotoca jacksoni, E. lateralis
Black surfperch, Striped surfperch
40
Embiotoca jacksoni
35
30
25
Number of offspring
20
15
10
5
0
1
2
3
4
5
6
7
8
9
10
11
12
35
Embiotoca lateralis
30
25
20
15
10
5
0
1
2
3
4
5
6
7
Female
8
9
10
11
12
Hippocampus barbiganti
Pigmy seahorse
Symbiosis
•  Fish - Fish
•  Fish - Invertebrates
•  Fish - Other vertebrates
Symbiosis
Trumpetfish / herbivores
Fish-Fish
Symbiosis Fish-Fish
Symbiosis
Trumpetfish / herbivores
Symbiosis
Fish-Fish
Alternative Strategies
Symbiosis
Fish- Inverts
Clownfishes / Anemones
Pearlfishes and Sea Cucumbers
Goby and Ghost Shrimp
Symbiosis
Fish-other verts
Symbiosis
Fish-other verts
Symbiosis
Fish-other verts
Vendellia cirrhosa
Urinophilus diabolicus
Symbiosis
Fish-other verts