seahorses wsorc

1. S E A H O R S E S
1 0 1 With K-Dog

2. • Taxonomy
• Evolution and Fossil Record
• Distribution
• Anatomy
• Reproduction and pregnancy
• Predators and human threats
• Protection and conservation
status

3. T A X O N O M Y
• 120 species names
proposed over last 200
years
• Project Seahorse
recognizes 47 species
• Genus: Hippocampus
• Family: Syngnathiformes,
related to pipefish

4. E V O L U T I O N &
F O S S I L
R E C O R D
• Two pipefish-like fossils found in
Slovenia each 13 million years old
• Molecular, physical and genetic
evidence shows seahorses are
highly modified pipefish
• Molecular dating finds that
seahorses and pipefish diverged
during Late Oligocene
• Speculation of evolving in response
to large new areas of shallow water,
created following recent tectonic
events

5. Distribution
• Usually live in seagrass beds, mangrove roots, and coral reefs in
shallow, temperate, and tropical waters
• Roughly range from 50°N to 50°S latitude
• Habitat degradation threatens species as they inhabit shallow areas
that are easily influenced by human activities
• Non-migratory: cannot move if home habitat is destroyed

6. S U R V I V A L
• Natural lifespans virtually
unknown
• Estimates range from 1
year lifespan for smaller
species to 3-5 years for
larger species

7. A N A T O M Y
• Unique features
• Have no scales, thin membrane covering
series of bony plates visible as rings around
trunk and tail
• Rings, cheek spines and coronet useful in
identifying species
• Have no stomach or teeth, instead use tubular
snout
• Inefficient digestive system
• Breathe through gills like other fish
• Swim using propulsive force of a quickly
oscillating dorsal fin, use pectoral fins on
either side of body for maneuverability and
stability
• Males can be identified by presence of a
brood pouch

8. S I Z E A N D
C O L O R I N G
• Size range varied by species
• Australian big-bellied seahorse (H.
abdominalis) can surpass 30cm
• Pygmy seahorse is less than 2cm
• Weight varies by reproductive stage
• Quick, short-term color changes may
occur during courtship or daily greetings
during pregnancy
• Masters of camouflage
• Can grow bumps on rings or skin
filaments to blend in with surroundings

10. F E E D I N G
• Opportunistic rather than
dynamic predators
• Smaller species mainly
feed on copepods
• Larger species feed on
larger amphipods, caridean
shrimp, brine shrimp, and
peracarids

11. R E P R O D U C T I O
N
• Male becomes pregnant
• Sexual maturity determined
by presence of a brood
pouch
• Monogamous, couples have
a daily greeting every
morning during pregnancy
• Female inserts ovipositor into
male’s brood pouch and
releases eggs, male
fertilizes, eggs become
enveloped with tissues

12. P R E G N A N C Y
• Pouch acts like the womb of a female
mammal, complete with placental fluid
• Pouch fluid acts as an osmotic adaption
chamber, alters composition to
resemble surrounding ocean water
• Pregnancy usually lasts between 2 and
4 weeks depending on the species
• Young are miniature adult seahorses,
no parental investment after birth
• Most newborns between 7 and 12 mm
in length
• Average number of newborns ranges
from 100 to 200
• Can be as low as 5 in smaller species
or up to 1,500

13. P R E D A T O R S
• Less than 1% survival rate in young
• Crabs a common predator in
shallow waters
• In certain areas octopus and sting
rays have been known to prey on
young
• Have been found in the stomachs
of invasive lion fish in the
Caribbean
• Tuna will eat especially in times of
year when regular food sources are
in short supply

14. H U M A N
T H R E A T S
• Chinese medicine trade
takes about 150 million from
wild every year
• Curio trade takes about 1
million a year, taken live
and left to die in the sun
• Aquarium trade takes 1
million every year,
estimated that less than
1000 live past six weeks

15. The Curio
Trade

16. P R O T E C T I O N &
C O N S E R V A T I O N
S T A T U S
• IUCN Redlist includes 38 species
• 1 species listed as endangered
• 7 species listed as vulnerable
• 1 listed as least concern
• 29 listed as data deficient
• In 2002 seahorses were included
in Appendix II of CITES which
monitors and limits international
trade