Deep Sea 1

The Deep Sea

Mesopelagic

Deep Sea 2

Division of the Deep Sea Mesopelagic

Effective light penetration - 1,000 m.

Bathypelagic 1,000 - 4,000 m.

Abyssopelagic 4,000 - 6,000 m.

Hadopelagic 6,000 m. or

more

Deep Sea 4

Sampling Considerations The depth of the habitat

creates a logistical problem Animals arrive dead due to

the drastic pressure change These problems lead to the

possibility of inaccurate conclusions on population size

Deep Sea 5

Submersibles and ROV’s Submersibles and Remotely

Operated Vehicles (ROV) are the ideal method for sampling the deep sea

Alvin submersible. Photo source: WHOI

Visit the Alvin website

Deep Sea 6

Submersibles and ROV’s

Jason II Photo source: WHOI

Visit the Jason II website

Deep Sea 7

The Mesopelagic A world of twilight

which cannot support photosynthesis

Animals that live in the mesopelagic must deal with the Oxygen Minimum Layer

Deep Sea 8

Mesopelagic Fauna Krill and copepods dominate Arrow worms, squid, jellyfishes and other

invertebrates are important predators Most of the animals that live in the

mesopelagic have light organs or photophores

Deep Sea 9

The Deep Scattering Layer Many mesopelagic animals also migrate to the

surface waters at night to eat

Deep Sea 10

Mesopelagic Fish

Deep Sea 11

Bioluminescence Definition - _____________________________

Bioluminescence occurs most notably in the mesopelagic

Light producing organs are called ___________

What are photophores used for?

Deep Sea 12

The Deep Sea

The world of complete darkness

Deep Sea 13

Environmental conditions Light

Most of the deep sea is aphotic

Due to the dependence on the surface waters for nutrients, there is very little life below the mesopelagic

Deep Sea 14

Pressure Until recently, physiology on these animals

was very difficult since bringing them to the surface usually results in mortality

Deep Sea 15

Temperature At 1000 m temperature is 4-6 C

With an increase in depth temperature changes very little

There is no other habitat on the planet which exhibits such a stable temperature

Deep Sea 16

Adaptations of Deep Sea Organisms

Food is a limiting factor!

How do deep sea organisms ensure food capture?

Deep Sea 17

Adaptations of Deep Sea Organisms

Deep Sea 18

Hinged Head

You Have Beautiful Eyes

Deep Sea 20

Reproduction In a sparsely

populated world mates are difficult to find Most deep sea

fishes are _____________ and attract each other through bioluminescence

Deep Sea 21

Invertebrates Invertebrates are purple (jellyfish) or red (copepods) Many invertebrates are transparent

Deep Sea 22

Abyssal Gigantism The phenomena

where some species attain large sizes not seen any where else

Isopod – sea roach can reach 40 – 50 cm. (Bathynomeus giganteus)

Amphipod – 15 cm. (Alicella gigantca)

Deep Sea 23

Hydrothermal Vents Animals are found concentrated around hot

water geysers

Deep Sea 24

Chemosynthetic Bacteria Using sulfides bacteria

create organic compounds

Most animals have symbiotic relationships with the chemosynthetic bacteria

Vestimentiferan worm

These worms contain 10 billion grams of microbes per 1 gram of tissue!