Vanishing Horses and Dragons Flashcards
1
Q
leafy sea dragons
A
- Close relatives of sea horses
- Have larger bodies (up to 45 centimeters)
- Leaf-like appendages that enable them to hide among floating seaweed or kelp beds
- Same class as other bony fish like salmon and tuna
- The similarities are seen when they are stretched out
2
Q
Seahorses and Sea Dragons are members of the family______
A
Snygnathidae
- Greek SNY=together or fused
- Gnathus=meaning jaw
- Other fish in this family include the pipefish
3
Q
Seahorses belong to the genus ____
A
Hippocampus
- Hippo=horse
- Campus=monster
- 32 species of seahorses
4
Q
Seahorses and Seadragons characteristics
A
- “Horse like” head
- “Monkey like” prehensile tail (not dragons)
- “Kangaroo like” pouch (dragons carry the brood under the tail)
- “Chameleon like” eyes (they move independently of each other and in all directions)
- Instead of scales they have thin skin stretched over a series of bony plates that are visible as rings around a trink
- Masters of camouflage they can change color and grow skin filaments to blend with surroundings
- Range from 2cm high to 45cm high
- -Measured from the tail tip to the top of the coronet (head crown)
5
Q
environment of seahorses/seadragons
A
- Marine species
- Sea grass
- Mangrove roots
- Tolerate wide ranges of salinity
- Habitat degradation is a real threat
- Live roughly from 50S to 50N latitude
- Most species occur in the West Atlantic and IndoPacific region
6
Q
sea dragons are endemic to
A
australian waters only
7
Q
seahorses have an average life span of
A
1 year in small species
3-5 years in the largest species
8
Q
how do seahorses and sea dragons eat
A
- by sucking their prey through a tubular snout (bc of their fused jaw)
- -no stomach or teeth
- -inefficient digestive system but nobody understands why
9
Q
sea dragons feed on…
A
- plakton
- larval fishes
- small shrimp-like crustaceans called mysids (“sea lice”)
- -they suck their prey up in their small mouths
10
Q
dragon predators
A
- Eaten by snakes, rays, water birds, turtles, and large fish, although most of this food source is in the form of babies
- -Unappetizing bony plates and spines when they get older
- -Sedentary lifestyle
- -Great camouflage
- -Translucent fins
11
Q
motion/swimming
A
- only a small subset of fins:
- -a small dorsal fin
- -tiny anal fin
- -two very small pectoral fins located on either side of the body
- they manage directionality but not speed
- steering is through movement of tiny, translucent fins along the side of their head (pectoral fins) and propulsion derives from the dorsal fins (along the spine)
12
Q
seahorses breeding
A
- During mating the females deposits up to 250 eggs into the “brood pouch” on the underside of the male’s tail. After about eight weeks, the brood hatches, but in nature only about 5% survive to maturity
- The pouch acts like a womb
- Provides nutrients and O2 and removes wastes
- The fluid surrounding the seahorse changes through pregnancy from similar to body fluid to more like surrounding sea water
- Breed twice a year
13
Q
mate for life?
A
- Most studies suggest that in the wild these fish appear to be monogamous
- Bonds are reinforced by daily greetings in which the male and female change color and “dance” together
- The dance lasts several minutes and then the pair separates for the day to go forage
- Pregnancy lasts form 2-8 weeks depending on species
- Gestation ends with the male going into labor at night pumping out his brood for hours
- Young are independent at birth
- Males give birth to 100-200 young; however, the smaller horses can deliver as many as 1500 at once!
14
Q
sea dragon breeding
A
- eggs in the “cups” on the sea dragon’s tail
- -a variation from the seahorse pouch
- hatching from the cups…the male gives birth
15
Q
what occurs for two to three days after birth
A
the babies are sustained by their yolk sac until they are large enough to hunt for themselves
