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The Deep Sea- BenthosOcean Regions

Major Benthic habitats

• Epifauna

• Infauna

Community Structure

• Few filter feeders (less than 7%)• Deposit feeders common (80%)• Often continuous breeding

Lack of Hard Benthos Diversity in the deep

• Most deep sea species are rare, so even with low numbers of total animals, relative diversity is high.

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Hydrothermal vent (Smoker)Very fast growth- Ephemeral

Hydrothermal Vents

• Discovered in 1976 with Alvin on Galapagos rift at 2700m

• Warm water (up to 400°C)• Chemosynthesis

– H2S Hydrogen sulfide energy sourcesulfate

Bacteria make the world go round…

• VestimentiferanWorms

Harbor symbiotic Bacteria in “gut”trophosome

Fast growthHigh mortality

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Lamellibrachia

• 250+ years

Vent food webs

Vent fields of the world Methane “Seeps”

Methane cold seep with clamsStable environments

Brine Lakes and Methane

methane hydrates

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Whale Falls

Chemolithoautotrophic Bacteria

• Food source for all vent and seep systems

Deep sea Nurseries