Lecture 36 - Marine Environments Flashcards
What are 4 categories of marine animals?
- plankton
- nekton
- benthos
- decomposers
What are plankton?
-weakly swimming, free-floating biota
What are 3 types of plankton?
- Phytoplankton (plant)
- Zooplankton (animal)
- Ultraplankton (photosynthetic bacteria)
Nekton EX
fish, turtles, whales
Benthos EX
bottom dwellers (barnacles, oysters)
What are decomposers?
-breakdown organic compounds (mostly bacteria)
Where is most action?
-Costal waters
2 characteristics of the Coastal Zone
- warm, nutrient-rich shallow water
2. extends from high-tide mark on land to gently sloping/shallow edge of continental shelf
What are Estuaries?
Where rivers enter the ocean
EX: river mouths, inlets, bays, sounds, salt marshes etc.
What are salt marshes
- some of most productive habitats on earth
- serve as fish nurseries
What is SAV?
- submerged aquatic vegetation
- Eelgrass
What is a Mangrove forest?
- found along 70% of gently sloping sand/silty coastlines
- tropical/subtropical regions
What is a kelp forest
- contains certain type of plant that forms forest
- houses resident fish + visitors
What is the effect of sea otters on kelp forests?
- eat the urchins
- otherwise kelp will die
What is Coral bleaching
-corals lose their zooxanthellae when stressed
5 traits of coral reefs
- 1-9 millino species
- 1/2 ocean’s total biodiversity
- high level of producitivty
- 100 million people directly dependent on healthy coral reefs
- threatened due to ocean acidification
What is the deep sea? (3)
- cold, dark immense pressure
- little to eat (not lifeless)
- largest habitat on planet
5 realms of the deep sea from shallow-deep
- Mesopelagic
- Bathypelagic
- Bathyal
- Abyssal
- Hadal
3 characteristics of animals in Mesopelagic Realm
- small size, huge eyes, large jaws/teeth
- bioluminescence + countershading
- Daily (diel) vertical migrations
6 characteristics of bioluminescence
- biologically produced light
- symbiotic bacteria
- predator avoidance
- species recognition
- prey attraction
- mate attraction
What is countershading?
-lights on underside make fish less visible from below
What are lantern fish?
-last unexploited stocks of fish (could change soon)
What is the Deep Scattering Layer
- worldwide phenomena after WWII
- detected by sonar
5 key characteristics of the Bathypelagic Realm
- bigger individuals (lower biomass, abundance)
- high species diversity
- black + red in color
- no vertical migrations to surface
- small/large eyes, bioluminscence
