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What are the major currents of North America
Gulf stream; Straits of Yucatan; loop current; straits of Florida; West Gulf.
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What is the Gulf Stream?
Current that flows from south to north along east coast; when it reaches cape cod Mass., it tend to veer east toward Europe
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What intersects the Gulf stream?
A cold current coming from the north and the Straits of Florida from the south
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What are the Straits of Florida?
Current that flows from out of the Gulf of Mexico between Florida and Cuba to the major current. It is fast and strong
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What is the loop?
Current within the gulf of Mexico
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Gulf of Mexico
Mississippi river, Rio grand yucatan penninsula, cuba and florida
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What is the STRAITS of YUCATAN
Between yucatan penninsula and cuba-strong(black)
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West Gulf(blue dotted)
usually current going S--> N can rejoin loop current, but in winter it can reverse-depends on weather and miss. River
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What is the name of the area where the West Gulf Current splits?
big shell and little shell-its unpredictable
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What are Gyres?
LARE SCALE GYRES-big scale patterns ex If follow Gulf stream-to europe, down africa then back on up
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Smaller Eddies
Loop current is notorious for forming them; it is what kept oil more concentrated instead of spreading down to cuba ; can also trap trash and garbage
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California current
- runs from N=> S
- Water quite cold
- So fauna is different than in warm water of gulf-DUH!
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Ekman spiral:
- Caused by Coriolis force causes current to reverse at depth
- N hemi=East coast S->N; W coast N->S
- At equator, things reverse-at places can sea water in bucket spiraling in opposite directions b/c coriolis forces
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UP WELLING
- If wind blows from sea to land, can cause a vacuum=> deep cold water moving up
- Occurs in California-especially in August
- Typically occurs on west coasts
- Have it in place where currents meant
- GOOD FOR FIHSING-brings up nutrients=>little fish=>BIG fish
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Carolinean fauna
- N. Gulf, temperate waters; discontinuous: N. Carolina to N. Florida, Gulf of Mexico from NW Florida to NE mexico
- See: blue crab, oysters, white shimp, whelks
- Typically default fauna of TX, b/c can survive cold and mud etc
- Due to sea way over Florida in past
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Caribbean Fauna
- To south, coral reefs, mangroove swamps
- Confined to areas that are warm, clear and nice
- Cribbean coral reef fauna has genera and families in common with other tropical areas that are seperated from it now
- Corals, some fishes( angel fishes, damsel fishes), cone shells, etc
- Ex. May see different species, same families in florida, red sea etc
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Tethyan distribution
- World-wide tropical distribution with fossils to early mesozoic era-200 mill years ago now divided up
- BIODIVERSITY HIGH
- Part of Caribbean fauna???
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NORTH PACIFIC FAUNA
probably invaded N. Atlantic across the arctic-North pacific cold water has tons of things that are only found there
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Plankton
Organisms in the H2O, cannot swim against current from Greek: to wander/move around
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Plankton sizes
Nano-; micro-; macro-; megaplankton
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Nannoplankton:
microns, bacteria etc-COMMON in poluted water
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Microplankton:
.1 mm or so, tiny algae
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Macroplankton:
1-10 mm [size usually sampled]
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Megaplankton:
- bigger (medusae(jelly fish) etc)
- when collecting Need to know:
- what size you want to collect=> avoid clogging
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Some sampling methods
Water pump; water bottle; net; continuous plankton recorder
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H2O bottle
-one time sample, wont get megaplankton, may get lots or very little
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Net:
mesh size (2mm)=> catch macro or mega plankton
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Continuous plankton recorder
- Collects and preserves plankton on mesh and keeps roll of mesh in preservative but Have to choose mesh size & it squishes the things it collects then Later Count organisms
- Computer program recognizes certain shape=> you only have to count orgs with weird shape
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Phytoplankton:
- photosynthesis: take up CO2
- Bases of oceanic food chain in many areas
- Trophic level
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Remember, metabolic isn't perfect-10% energy transfer
Ex 1,000,000 lbs of phyto plankton: Primary producers (1o)=> 100,000 lbs of Primary consumers (copepods)=> 10000lbs of secondary consumers (2o)[small fish]=> 1000 lbs of thrird degree (mackerel)=> 100 lbs of fourth degree consumers(tuna)=> 10 lbs of 5o consumers=> 6th degree consumer(killer whale or great white)
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Types of plankton
- Diatoms-case(frustule) of silicon dioxide (SiO2)
- Shaped live petri dish-upper and lower lid
- 2 general shape: centric=round pennate=elongate
- Can have asexual reproduction produce resting stage, sexually reproduction seasonally
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DINOFLAGELLATES
- Have flagella, spin, can have small plates or naked; Can be toxic: RED TIDE =>Get massive fish kills
- Reason why can't eat shellfish in different times in CA Shapes:
- Many different
- Ceratium-having horns
- Noctiluca-night light
- Some have bioluminescence
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Primary Productivity
- Incorporation of CO2 into useable carbon compounds
- Seasonal according to light, temperature and sufficient nutrients
- In poles, only get bloom in summer cue to temperature
- Others=peaks at may and october
- Tropics-no rain season=frequently
- Photo plankton believed to produce about 1/2 net 1o production world wide
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Measuring 1o
Count cells; satellite; C14 method; chlorophyll reflects lightl light-dark bottle
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Satellite measurements
- Only measures at surface so if clear day, may miss lot of plankton bellow
- Chlorophyll reflects light
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C14 method
incorporation rate of C into cells in lab
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Light-dark bottle technique
- 2 bottles of same volume with plankton sample: 1 clear and 1 dark
- Measure oxygen in each
- Photosynthesis in light bottle=> oxygen produced
- Respiration in dark bottle=> uses oxygen
- Light bottle measurement at end-dark bottle=net primary production
- Allows counting of chlorophyll
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SUPERSATURATION-
causes O2 bubble
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Zooplankton
Primary consumers, eat phytoplankton=>lag time after phyto bloom b4 their bloom
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Alternate food loop
- Dead phyto, zooplankton, fishes etc sink & decompose by action of bacteria
- bacteria eaten by one-celled organisms(protozoan)
- Zooplankton eat protozoans
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Types of protozoans
Ciliates radiolarians and foraminiferans
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Ciliates, radiolarians
(shells of SiO2); Radiolarians look like Christmas bells; fragile and difficult to preserve for viewing-have Pseudopods
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foraminiferans(forams)
- Shells of CaCO3; picky about environment: salinity etc
- Feed like venus fly trap etc
- Only about 1 mm across
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Zooplankton Types;
Holoplankton; Meroplankton; copepods; Trocophore; barnacle nauplius; meroplankton
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Holoplankton
- Entire life cycle in water column-most phytoplankton and copepods aka always plankton and only plankton
- Arrow worm (phylum Chaetognatha-{keytonath})-Eat copepod by detecting vibration caused by copepod movement
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Meroplankton
- Larval stages or juveniles in water but adults on sea floor or actively swim
- Adult to corresponding larvae isn't known all the time-may find larvae but not know what adult looks like
- Most zooplankton, except copepods are these
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Copepods
- Most common zooplankton; Has only one eye, antennae ; Many eat diatoms(most common photoplankton); Everything is eating them
- Sensitive to oil pollution
- Larval stage: nauplius
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Trochophore
- Larva of worm or some mollusles ie slipper shell
- Resemble ciliated”tops”
- Most are meroplanktonic with non-planktonic adult stage
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Barnacle nauplius
Looks like copepod but has horns
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Nauplius
Exclusive to arthropods-represent first larval stage of barnaclas, crabs, shrimp, copepods etc
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Meroplankton
- Veliger of clam or snail
- Will eventually settle on sea floor
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HOW to stay AFLOAT
- Very small animals or cells don't sink much
- Larger animals: avoid sinking by:
- Being flat; Containing gasses or oils ;Few hard parts; Large surface area; Gelatinous
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OCEAN SURFACE organisms
Called NEUSTON-Man of War; Sea penny, by wind sailor; anthina; Sargassum organisms
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Anthina
- Snail that eats man of war and wind sailor
- Purple tint due to eating them
- Lays egg inbubbles
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Sargassum seaweed
- Has Floats, reproduces asexually
- Will find small organisms that grow on seaweed-look like frosting eaten by: sargassum shrimp, nutibranch, crab
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sargassum crab (Portunus)
Fingerlength, mean
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Sargassum fish (histrio)-cannabilistic
- Mouth opens to width of body
- GLOMPS
- Lives among seaweed
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Nekton:
- actively swimming animals in water column
- All vertebrated and cordated
- Tail; gills; Usually have eyes; Seperated by amphioxis b/c fish have definite head and brain
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3 classes of Nekton
agnatha, chondrichtlyes; Osteichthyes
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Agnatha
Many fossils, but few living species-no jaws, simplified brains; look like eel/snake
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Hagfish:
Agnatha class; scavenger, extremely slime 500-600m
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Lampreys
Agnatha class =Eel like; Sucking mouth disk with teeth and rasp flesh from larger fishes and marine mammals
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Chondrichtlyes
- Fish class containing Cartilaginous fishes-sharks and rays [Only place with CaCO3 is the teeth=>not much fossils]
- Many gill opening, tough skin
- Side/lateral fins are fixed=> move like jet plane-no small adjustments
- Sexually diamorphic-Male has claspers
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Predators Chondrichtlyes
- great white shark, eats fishes, marine animals-migratory
- TIGER &bull Sharks-Do come closer to shore; eatSea turtles etc
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Bottom feeder Chondrichtlyes
Horn shark, rays-crush prey-Do the shuffle!
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Plankton feeders Chondrichtlyes
- Whale and basking sharks-Harmless to people-they're 25+ feet and really don't care
- Whale are spoted
- Basking sharks just open their mouths-they have raking system in their mouths
- Bonnet head-Caught in Port A frequently
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Osteichthyes
- Bony fishes; CaCO3 bone, 1 gil opening; can have scales
- New species found all the time
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Open water species Osteichthyes=pelagic
- Streamline: fast and tend to be torpedo shaped; Lunate (cresent moon) tail; narrow body and fins; effient physiology Retain body heat-transferred in gills; Have myoglobin in flesh; Swim bladder can have fats and oils EXAMPLES-Tunas, jacks, wahoos, marlins. Mahi-mahi
- Planktonic fish larvae
- Ocean sunfish(Mola)
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Reef fishes Osteichthys
- Any fish fear rocks, corals, shipwrecks; Often can hide, dart into holes
- Fins are paddle-shaped;Body not as narrow or streamlined
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Damsel fish
Territorial -Male guards eggs;Crate nests;Often brightly colored;Male funs female off after female lays eggs
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Sergeant major in TX
Will beat up other fish
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Sea bass or grouper family
- Gulp prey whole
- Eels can have lateral fins
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Demersal fishes
- Move on and off sea floor-flat bentral surfac
- Flat fishes start as upright larva, 1 eye migrates to side; lie outside
- Halibut-largest get to be 8 ft long
- PLAICE-type of fish that can blend-able to change color and do poka dots but no checkerboards
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Cat fishes
Have sensory whiskers
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Compensation depth
- -where photosynthesis=respiration;Varies in different area due to murkiness ex some prt of Galv:6 inches and parts of open ocean 6K ft
- Below this depth, there may be faint light Vs NO detectable light at aphotic zone-also varies
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Temperature and depth
Generally water is warmer at surface especially at Gulf(22C)]; Thermocline usually present-In Gulf of Mexico-usually has BIG one 1000m
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Oxygen
- Mixing between water is minimal=> OXYGEN minimum zone
- Usually more oxygen above and below O2 minimum zone b/c Above-waves; below-coreolus effect and currents
- Mixing=> NO stratification Port A is too shallow for Stratification
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Stratifcation
No mixing across thermocline=>layering of water "Stratification"
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Effect of DISTANCE from LAND
- Farther from land=> less nutrients=>less diatoms; Also matters how big land is
- Primary production from photosynthesis is much less at distance=>Microbial loop is more important
- b/c bacteria have proteins-some may be toxic but lots that decompose things are covered in protein and thus become energy rich food snack for small organisms
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what happens Below compensation depth/above if minimal primary productivity
Dinoflagellates can be heterotrophs-They can be photosynthetic, then glomp onto bacteria when not enough light then go back again when light
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Adaptations to midwater life
- Few or weak hard parts-almost gelatinous;If swim, tend to do so in pulses exJelly fish: flap, glide, flap, glide
- Can have myoglobin in tissues exJelly fish-myoglobin retains O2 and makes sturdier
- Eyes present or not-If present, can be peculiar; Big bug eyes, eyes on stalk; disproportionate eye size; Some may have no eye lid
- May use fats in body for buoyancy or secrete gasses
- Can have extensive sense organs-Lateral line in fish is capable o sensing changes in pressure
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Catching & keeping food midwater zone
- Sharp teeth ;Big mouth&large stomach exPELICAN EEL aka GULPER eel;
- Lures-Angler fish
- Fishes and some fish have photospores-light organs:If animal at bottom end of photozone-camifloage; Breaks up outline of critter=>think 1 fish is many
- Bioluminescence also used forCourtship; Lure; Luminous cloud ex Shirmp-expell bacteria=> act like somke screen of color
- Lighted body(not due to photospores) rather caused by Ca reaction
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Under water fish concentrations
- Dense concentration of fishes, shrimp and jellies at O@ minimum zone;May reflected by gas
- Sonar learned to distinguish between things and hard object;
- Soft and squishy=> not a good food source for humans despite dreamers ideas
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Vertical migration
- Move up at night, down by day
- Most animals stay within certain depth
- Ladder of migration
- Passive sinking of food
- Diatom at surface dies,sinks and is decomposed by bacteria deeper
- This sinks and eaten by small creature; sinks; lag time at O2 minimum zone
- Always a lag time there due to density etc
- Passes through minimum zone and later re-eaten; deficated and eventually hits sea floor
- Spend time mostly in midlevel-possible that juvenile are higher, but don't know b/c can't always match
- Eventually sink to sea floor
- Some species of deep sea are only known due to stomachs of other animals
- Prince of montico would go to commercial whalers and have his servants take out stomachs and look at squids that have never been seen by humans
- Don't really know parasites
- Salinity of normal SW
- 35ppt
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Salinity of hypersaline
40ppt
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Salinity of hyposaline
23ppt
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Composition of Sea Water
- Has NaCl, Mg, P and other compounds
- Nutrients(salts)needed for algal and plant growth
- Nitrates(NO3-) can be limiting b/c low concetrations far from shore
- Occurs most on land b/c nitrogen fixation provides it
- Phosphates(PO42-)-limiint
- Silicates-diatoms-food
- Carbonates-shells and bones
- ~Essential for coral growth
- ~Affected by acids and low temperature
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Thermocline
Abrupt change in temperature
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Dangers for humans-depth
Coming up gas pressure lessens=> air breather must decompress 2ft/sec or else gas will bubble in tissue=BAD
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Selective absorption of wavelengths
red light lost first blue last
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How is energy used?
basic metabolism, growth, reproduction
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BIG ENERGY USERS
locomotion, care of young& advanced/complicated nervous system(brain/spinal cord); active transport
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Open Sea environment
- Stable environment-Areas without large rivers or bays =>Most organisms here either can't deal with change or only able to adjust to gradual change-ie seasonal migration
- Many animals rely on diffusion for metabolic process: respiration, excretion
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Living in water
- Organism must have high surface area to volume ratio=THIN&FLAT
- Rely on H2O for body support; some have "hydrostatic skeleton"
- Can be gelatinous-water keeps it up-JELLY FISH(medusae)
- Usually sufficeint free O2: use gills, diffusion, Aerobic respiration
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Low or anoxic situations:
anaerobic respiration, lactic acid cycleBacteria often times, water can be crystal clear b/c nothing can really survive in anoxic water
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Sessile
- Attached to surface;Body is highly reduced-internal organs don't consist of much
- Has complex feeding apparatus but that’s pretty much it
- Ex Tunicates-Sea squirt
- In larval state-has fish like appearance before it looses vetebral column etc when they settle down
- Have to look very carefully to learn they are animals vs plant
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Reproduction
Many SW plants and Animals rely on SW for reproduction
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External fertilization:
- release gametes in H2OOther animals eat the caviar-if see them spawning, expect to see larger animals swimming above and eating
- Embryo forms, larval stage-free in water or in egg case
- Can gave intiferrt but release juveniles or larvae
- Larval stages or other stages carried by currents deisperse the spawn
- Lots of interdependence
- Land has more species due to insects
- Oceans have more phial taxis etc-much older even if less diverse
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