Fishes as prey avoiding predation Avoidance of predators

Predator – Prey arms race • Co-evolution of predatory and escape mechanisms – Morphological

Predation Cycle • • • Search Pursuit Attack Capture Handling of Prey

Detection avoidance • Camouflage (avoidance of visual predators) Appearance of something unrecognizable Disappearance -

Detection avoidance • Pelagic camouflage (avoidance of visual predators) – Countershading

Detection avoidance • Pelagic camouflage (avoidance of visual predators) – Countershading – Mirror sides

Pursuit evasion • Morphological adaptations – Stout and/or sharp spines – Poisonous spines –

Pursuit evasion • Morphological adaptations – Stout and sharp spines – Poisonous spines –

Capture and Handling discouragement • Body armours • Long dorsal and anal spines •

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Fishes as prey: avoiding predation Avoidance of predators Adaptations of prey

Predator – Prey arms race • Co-evolution of predatory and escape mechanisms – Morphological adaptations – Behavioral adaptations – Ecological adaptations “there is no perfect predatory nor perfect escape tactic”

Predation Cycle • • • Search Pursuit Attack Capture Handling of Prey

Detection avoidance • Camouflage (avoidance of visual predators) Appearance of something unrecognizable Disappearance - become invisible – Protective resemblance • Resemble background • Resemble inedible objects • Resemble predators

Detection avoidance • Pelagic camouflage (avoidance of visual predators) – Countershading

Looking upwards Looking downwards

Looking downwards

Detection avoidance • Pelagic camouflage (avoidance of visual predators) – Countershading – Mirror sides

Mirror Sides

Detection avoidance • Pelagic camouflage (avoidance of visual predators) – Countershading – Mirror sides – Transparency

Detection avoidance • Pelagic camouflage (avoidance of visual predators) – Countershading – Mirror sides – Transparency – Counterillumination (Bioluminescence)

Hatchetfish Myctophid lanternfish

Detection avoidance • Pelagic camouflage (avoidance of visual predators) – Countershading – Mirror sides – Transparency – Counterillumination (Bioluminescence) • Olfaction avoidance (Avoidance of olfactory predators) – Mucous cocoon

Pursuit evasion • Morphological adaptations – Stout and/or sharp spines – Poisonous spines – Toxic fishes Usually with Aposematic Coloration (but not always)

Pursuit evasion • Morphological adaptations – Stout and sharp spines – Poisonous spines – Toxic fishes Usually with Aposemotic Coloration • Behavioral adaptations – Use of bottom shelter – Use of holes and caves – Flying

Capture and Handling discouragement • Body armours • Long dorsal and anal spines • Extra deep bodies • Inflation • Erection of sharp spines ….