Marine Bio Final Pt.1

characteristics of deep sea

* no light
* constant cold temperature
* low variability
* high pressure

diversity pattern

* highest at intermediate depths
* declines with increasing depth

abundance

* declines with depth


* likely due to decreasing food availability


* decomposers


* deposit feeders dominate (mobile bc of sparse food)


* omnivorous scavengers

sources of food

* main: marine snow (plankton and materials rain down)


* sinking of larger organisms and seaweed clumps (whale falls)


* decomposers: decomposition very slow
* chemosynthesis

adaptations - benefits of bioluminescence

* finding mates, communication
* luring and finding prey
* escape behavior
* counter illumination
* confusing pred or prey
* burglar alarms

adaptations for high pressure

* no gas spaces (swim bladders)
* high water content (buoyancy)
* small size
* reduced ossification: gelatinous, blob fish

adaptations for low food availability

* consume whatever prey there
* feeding: large mouth, vertical migration, symbiosis
* switch from planktonic food sources to deposit feeder or predator strategies

adaptations for reproduction

* finding mate use light and scent
* dwarf or parasitic males
* long lives

adaptations for temperature

* specialized enzymes
* slow metabolism

adaptations for growth

* gigantism
* long lives and slow growth because less food and oxygen and cold

deep sea - unique habitats

* vents
* cold seeps
* seamounts
* deep coral mounds
* local and ephemeral food sources (whale falls)
* hadal trenches

hydrothermal vents - where

* mid ocean ridges where hot water emerges
* upwelling of magma, volcanic activity

vents - food source

* main: chemosynthetic sulfur reducing bacteria (free living or symbionts in bivalves and tube-worms)

cold seeps - where

* worldwide depths from 500-4,000m
* tectonically active places where hydrogen sulfide, oil, methane, and highly saline waters leak out to form brine pools
* production of carbonate rocks and reefs
* deep sea escarpments (Gulf of MX) can also leak lots of hydrocarbons and sulfides

cold seeps - characteristics

* slower growing
* longer lived
* cold version of h vents
* main food source: chemosynthetic sulfur reducing bacteria

seamounts - location and characteristics

* relatively isolated elevated areas, usually volcanic origins
* upwelling and high productivity
* can have deep coral mounds (delicate, slow growing, no zooxanthellae)

whale falls - characteristics

* predictable pattern of succession: mobile scavengers → polychaetas and gastropods remove larger pieces → bacteria, mussels, bone worms
* more common historically

methods for sampling deep sea

* benthic: blind grabs and dredge, box cores, GPS guided coring, submersibles
* deep sea nekton: trawls, submersibles

characteristics of estuaries

* unique invertebrate and fish assemblages
* food web structure
* nursery for nekton (fish and decapods)
* human importance

3 types of estuaries

* shallow, well-mixed with large freshwater input
* lagoon, hypersaline systems
* fjord systems, poorly mixed

shallow well-mixed estuary examples

* Pamlico sound
* Chesapeake bay
* Cape Fear

shallow well-mixed characteristics

* goes from fresh to salt
* well oxygenated
* river input normally
* typical estuary

extra:

* gradients in mixing and vegetation
* temporal spatial variation in salinity
* cline in substrate type
* seasonably variable planktonic production
* may have reduced or seasonal pred numbers
* sink for organic matter
* high abundances of a few species
* diversity declines going to low at 5ppt then increases toward freshwater
* turbidity max

lagoon examples

* Laguna Madre
* Mediterranean
* Australia
* Masonboro sound

lagoon characteristics

* high salinity
* hot
* separated
* not much freshwater input
* high evaporation
* diverse, lower abundance
* seasonality dampened
* lower productivity

fjord examples

* canadia and scandanavia
* some basin areas

fjord characteristics

* deep
* stratification
* low oxygen at depth
* sill at mouth restricts flow to deeper
* low productivity
* freshwater influence in shallow areas
* oligotrophic (low nutrients)

estuary vs ocean differences

* shallow well mixed may have high faunal abundance
* fewer trophic levels
* fewer species and lower diversity
* high resilience but low resistance to change

estuary as nursery

* habitats: seagrasses, salt marshes, oyster reefs
* seasonal peaks in food supply: juveniles and larvae
* predator avoidance: grass shrimp, blue crabs
* habitat complexity
* separation of adult and juvenile pops

Cape fear habitats

* support fisheries
* varying salinity habitats: fish migrations, species use diff salinity zones during life stages
* open estuarine connection to ocean
* wetlands: stabilization, filter
* shellfish: oyster, shoreline protection, filtration
* island: nesting, marsh

Cape fear species (prob extra)

* silver perch
* mummichog
* penaeid shrimp
* blue crab
* grass shrimp
* vegetation: juncus roemerianus, phragmites australis, spartina altiflora
* mollusks
* crustaceans
* fish
* reptiles: alligator, terrapin
* birds: oyster catcher, bald eagle

cape fear management

* 14 important bird areas
* amendment: water quality, wastewater infrastructure, monitoring of key habitats, oyster restoration
* marsh and oyster restoration
* removal and redesign of dams
* fish ladders
* buffers, agricultural practices
* know chemical inputs
* recreational and commercial fishing best practices
* research, education

Chesapeake - habitats

* largest estuary in world
* commercial fisheries: blue crabs, striped bass, menhaden, oysters
* forests
* rivers and streams
* reefs and pilings
* beaches and tidal flats
* marshes and wetlands
* submerged aqautic vegetation
* open and shallow waters
* channels and islands

Chesapeake - management

* reduce pollution, restore habitat, manage fisheries, protecting watersheds, outreach programs
* Obama executive order to recognize as national treasure
* limit nutrient and sediment discharge

Inland seas characteristics

* marginal sea, semi-enclosed body of water, large
* restricted circulation

Mediterranean

* warm
* almost completely enclosed
* evaporation exceeds precip, relies on inputs from atlantic
* biodiversity of stable area
* current circulate to promote mixed settlement areas
* little seasonal change
* many species with higher biodiversity in coastal areas, cont shelves, decreases with depth
* intense human impact: pollution, tourism, overfishing, shipping, sea level change

Baltic Sea

* cold
* largest inland brackish area
* partially landlocked
* significant freshwater inflow
* long term ice coverage, decline with warming
* halocline: vertical stratification of water column, barrier to exchange of oxygen and nutrients, separate environments
* issues: eutrophication, overfishing, contaminants

Gulf of MX

* shape from plate tectonics
* very small tidal range from narrow connection to atlantic
* some areas very deep
* biota: shallow shoreline, cold seeps, supports important fisheries
* impacts: pollution, oil spills
* strong effect from Mississippi river, growing hypoxic zone

Coral sea

* many islands and reefs, GBR
* more open connections with surrounding ocean
* internal loop current can entrain larvae, could maintain diversity

commercial fisheries

* catching for sale
* part-time and full-time fishers
* part-time increasing in US

recreational fisheries

* not fishing for sale
* catch and release and personal consumption
* not as well reported
* can have equal or greater take than commercial in areas
* can have bycatch

fishery management

* agencies: control fishing times, locations, method, institute size limit and seasonal catch limit
* water quality and habitat protection measures
* limited entry
* commercial fishing and aquaculture zones
* education on practices
* no take zones

fishery national management

* national waters and autonomy
* international treaties
* vary per country
* outside nat economic exclusion zones: freedom to high seas, regional fisheries mngmt organization, UN organizations
* enforcement difficult

fishery management in NC

* many interacting agencies
* beyond 3 mile jurisdiction: federal fisheries management commission
* within state: division of marine fisheries,

fishery stressors

* overfishing: changes in food web structure, majority of fish on threshold

extra:

* destruction of critical habitat
* growing world population
* contaminant and sediment input
* climate change
* introduced species and diseases
* harmful algal blooms: shellfish poisoning