Jienne Al-Haideri, Seema Patel, Chithra Rajasekaran & David Yang

1.Introduction 2.Overview of Seahorses a. Morphology and Behavior i. brood pouches, snout, body, tail, dorsal fins ii. feeding, Sexual dimorphism 3.Conservation Concerns 4.Future Directions 5.Summary & Conclusions 6.Q & A

Seahorses Order: Gasterosteiformes Family: Syngnathidae Genus: Hippocampus o Ancient Romans/Aristotle o Size Range o Marine species

 Highly involved male parental care  Completely enclosed brood pouch  Function: Osmoregulation, nutrition, respiration, incubation site.  Comparisons  Pipe fishes: simple, inverted pouches.

 Males/females differ in their external anatomy

 Monogamous (mate for life; unlike most fish)  Dimorphism evolved from sexual selective pressures Ex: longer trunks in females accommodate developing ovaries longer tails in males aid in courtship (tail grabbing) and gestation (brood pouches) Note: Seahorses still maintain traditional sex roles

 Sit-and-wait predators  Camouflage  Rely on site (independently moving eyes)  Feed primarily on mobile prey—mainly crustaceans  Evolved from straight bodied swimmers (pipe fish)  Pivot feeding (2 step process)

 S-shaped body increases strike distance Main point: S-shaped body and sit-and-wait strategy evolved for better feeding

 elongated snout  various snout dimensions depending on species  snout length/width differences with age  pivots head to lessen distance from their snout to the prey  lift angles allow for a greater distance to be covered by the mouth Leafy Seadragon  Short-snouted Seahorse 

Anatomy of a Seahorse Head:

 lack scales  Body Armor: thin layer of skin covering several bony plates  Trunk rings and coronet  Coronet: "crown" structure positioned at head (equivalent to human thumbprint)  Camouflage used as a defense mechanism and predatory strategy (ex. Dragon Seahorse)  Armor makes them unappetizing prey

 Specialized prehensile (grasping) tail  Evolution of bent tail  Change in regulation of growth and development  Daily life  Attached to algae and corals  Social Behavior

 Highly specialized oscillations  High frequency median fin propulsion (unusual)  Habitat selected for high degree of maneuverability  Complex, obstacle-strewn environment

 Simultaneous prey and predator  Economic value  Chinese medicinal uses  50% decline in natural populations  Vulnerable due to behavior  Live in endangered environments  By-catch (e.g., Shrimp Trawlers)

 Evolutionary history is still controversial  Mystery of bending tail evolution  Phylogenetic relationships are poorly understood  Difficult to culture seahorses due to lack of information/data  Indicator species?

 Anthropogenic pressures need to be lifted  Overexploitation in target fisheries  Threats from habitat degradation  Exceptionally unique  Unique reproduction (male pregnancy)  Drastically changed the fish body plan  Vertical swimming style  They need protection!  Dramatic declines worldwide  Biggest predator is man