Estuaries are areas where

freshwater meets seawater

Estuary: San Francisco Bay

Chesapeake and Delaware Bays

Salt Marsh

Tidal mud flats and wetlands

Tidal channels in mud flats & wetlands

Tidal flat protected by bay mouth bar

Tidal mud flats in Nova Scotia

Distribution of Mangrove Swamps

Mangrove swamps in Mexico

Mangrove succession

Close-up of prop roots

Close-up of prop roots

D

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Wave-dominated Nile River Delta

River-dominated Mississippi Delta

Characteristics of the organisms in the twilight and

deep zones of open ocean:

1. small sizes of most organisms, but giants exist

2. large mouths with sharp teeth and expandable

stomachs to swallow prey as large as themselves

3. bioluminecent organs to lure prey, to identify and

communicate with members of their own species, to

distract other organisms hunting them

4. some organisms are transparent or red to hide

5. because many organisms in the water column

never come in contact with hard surfaces, they can

be delicately made.

Angler fish

Gulper eel

Bioluminescent, transparent, delicate, tiny octopus in the

aphotic zone

Bioluminescent, transparent, delicate, tiny squid in the

aphotic zone

Red shrimp in aphotic zone

Bioluminescent and transparent jellyfish

Bioluminescent Squid in aphotic zone