Bathypelagic zone

Question 1

Describe the Bathypelagic zone

Answer 1

1000m->3000m

There is no light

Plankton biomass is 1% of surface at 1000m and 0.01% of surface at 5000m

Question 2

Describe Bathypelagic (abyssal) fish

Answer 2

150 species at 1000 - 3000m

-includes 100 species of angler fish.

Reduced calcification
-except jaws and teeth

Watery muscles
-Angler fish and Gulper eels are 95% water

Feeding

• Large teeth
• Huge mouths
• distensible guts and body walls

Question 3

Give some examples of bathypelagic fish

Answer 3

• Lantern fish
• Hatchet fish
• Gulper eel
• Cyclothone
• Anglerfish
• Gigantactis

The Fangtooth - 16cm long but has proportiantely the largest teeth of any fish. Lives at 2000 - 5000m - the deepest living fish ever discovered.

Six-gilled sharks can grow to 4.8m. They cruise the ocean floor during the day down to 2,500m. They move to the surface at night to feed.

The frilled shark - rarely seen. It’s a living fossil found at around 1,500m

Question 4

What are some of the reproductive strategies of mesopelagic fish?

Answer 4

• Few large eggs
• Viviparity (live births)
• reduced skeletal and muscular systems saves energy for eggs
• mouth broodinig (retain eggs inside mouth for protection)
• dwarf parasitic male (as seen in the Angler fish, Linophryne)
• bioluminescence to attract and signal opposite sex.
• Vampire squid live in mesopelagic and bethypelagic regions at 3000m. Proportionally they have the largest eyes of any animal.

Question 5

What are some of the light adaptations of mesopelagic fish

Answer 5

• transparent eyeballs ensure maximum amount of light is captured.
• Large pupils like in the viperfish capture maximum available light.
• Tubular eyes point upwards as seen in the Hatchet fish.