6:20A PHYTOPLANKTON Spirogyra  The pelagic environment is the largest marine ecosystem. More food, oxygen and biota (life) are here than anywhere else. The dominant organism in the neritic zone and oceanic zone is plankton.Plankton are organisms that can not make a forward motion against a current.

Volvox  They produce 50-90% of all atmospheric oxygen, and are critical biomass.

Phytoplankton & Zooplankton.

Phytoplankton are photosyntheticautotrophs, who begin all marine food webs.

They are adapted to a floating life- style because of their:

1. small size - diffusion is quick, frictional drag from large surface area to low volume ratio helps slow sinking

2. structure - disks shaped or chains aid in floating

3. low density - light ions and lipid by-products of photosynthesis reduce density and aid floating

They are grouped by color. Different pigments allow them to take advantage of different light penetration at various depths.

6:20B Phytoplankton are found in 3 Kingdoms and 5 _ Phyla. 

Commercially, algae are used as emulsifiers to give a smooth texture to puddings, toothpaste, ice cream, and shoe polish. A "bloom" is an increase in population density of phytoplankton associated with high nutrient levels.

It can be the result of upwelling or excessive nutrients.

Upwelling is caused by winds and other atmospheric conditions that move surface water away from shore, pulling nutrient rich bottom water to the surface.

Normal upwelling

windocean

Happy fish

nutrients

Diatoms are dominants in cool water. Blooms are good for the food chain, fishing and trigger whale migrations.

6:20C

However, blooms of some plankton, especially in warm . water, may be harmful. When storms follow hot, dry weather, dormant cysts of toxic phytoplankton may be released.

As these toxic blooms enter the food chain, theygive off chemical neurotoxins that paralyzethe predator's nerves controlling breathing and heart rate.

Human consumption of these organisms result in paralytic shellfish poisoning due to biomagnification.

The dominant phytoplankton in warm water are Dinoflagellates. They cause a condition called red tide.

flagella is a tail-like structure

Red tides is a result of a wind pattern, Peruvian fishermen named EI Nino. The name refers to the Christ Child, because the condition was first observed during the warm, Christmas months of the southern hemisphere.

A change in winds direction blows surface water toward the land and prevents upwelling. Water is depleted of nutrients and fishing is poor. 

wind

ocean

No upwellingland

El Nino

6:21A 

ZOOPLANKTON

Zooplankton are the primary consumers,called heterotrophic herbivores, in food webs.

They are the smallest and most numerous marine animals. Their population density depends on the availability of phytoplankton upon which they graze.

There are two groups of zooplankton:

1. Meroplankton - planktonic larvae who will become adult forms of fish, worms, Mollusks, and Crustaceans

Crab zoe

The advantage of meroplanktonic lifestyle is reduced competition from adults for the same basic needs. However, predation is extremely high because of their size and lack of adaptability.

2. Holoplankton - will remain plankton throughout life. They remain visible, but tiny.

Adult Daphnia

6:21B VERTICAL MIGRATION

__Copepods (Phylum: Arthropoda) are 95 % ofall zooplankton. Others are krill, foraminiferaand members of Kingdom Protista, Phylum Protozoa.

copepodkrill

foraminifera

Zooplankton are grouped by the way they move - either by pseudopods like the amoeba (1), flagella like euglena (2) or by cilia as in paramecium (3). .

Amoeba Euglena Paramecium

Noctiluca

Nostoc

Stentor

Vertical migration is a daily pattern of phytoplankton _and zooplankton changing positions like a day and night shift. During the day phytoplankton produce lipids by photosynthesis.

Because oils are less dense than water, the products of photosynthesis increase their buoyancy.

6:21 C

As the sun goes down, the phytoplankton use lipids for energy which causes them to sink in the water column. In response to the "rain" of phytoplanktondescending, the zooplankton move up in the water column to graze on them.

As the sun comes up, photosynthesis again causes more production than the organisms need at that time, the phytoplankton become lighter and begin to float upward. 

The zooplankton begin their downward response to graze _ again and to take advantage of reduced visibility and heat at the surface.

 

These two periods of grazing 1. protect both populations, 2. reduces predation 3. distributes stress in the ecosystem.

Phytoplankton movedown

ZooplanktonMove up

Grazing

time

6:22A TAXONOMY

Taxonomy is a system of grouping organisms based on phy logeny (evolutionary relationships), biochemistry and mor phology (structure).

There are seven taxa: 1. Kingdom: The 5 Kingdoms are (1) Monera, (2) Fungi, (3) Protista, (4) Plantae, (5) Animalia 2. Phylum: major marine phyla from Kingdom Animalia: (1) Porifera, (2) Cnidaria, (3) Annelida, (4) Mollusca, (5) Arthropoda, (6) Echinodermata, (7) Chordata

. Class: major marine classes from Phylum Mollusca: (1) Gastropoda,

(2) Pelecypoda, (3) Cephalopoda

from Phylum Arthropoda: (1) Crustacea

from Phylum Chordata:

(1) Chondrichthyes,

(2) Osteichthyes,

(3) Amphibia,

(4) Reptilia,

(5) Aves

(6) Mammalia

4. Order: subgroups of a class; for birds and fish the suffix is "formes" 5. Family: subgroups of an order; suffix is "ae" ex: Hominidae 

6:22B

6. Genus: subgroups of families; first part of scientific name and always capitalized ex: Homo 7. Species: "specific" organisms that can produce an offspring; second part of the scientific name and always lower case ex: sapiens

 Carrolus Linneaus developed a system of naming organisms based on visible characteristics. The use of terms - genus and species - is called binomial nomenclature or the scientific name. A dichotomous key is used to identify the names of unfamilial organisms. The key is based on two choices for each pair of related characteristics. Only about 1 million of nearly 10 million organisms have been identified and namedso far.

_. Scientists use a revised system based on biochemistry to name all the discovered organisms.

6:23A ORDER CETACEA- WHALES, DOLPHINS, PORPOISES

Phylum Chordata; Class Mammalia

Cetaceans are grouped on the basis of their mouths:

a. Mysticeti - whales with baleens (strainers) for plankton; both nostrils have a blow hole

Humpback whale

b. Odontoceti - whales, dolphins and porpoises withteeth; carnivores; 2 nostrils but only

_ 1 blow hole; smaller in size

Killer whale

Marine Mammal Characteristics:1. hair (at birth)2. nurse young3. breathe air4. warm blooded5. placenta6. horizontal tail (ALL marine cetaceans)

1.2.3.4.5.6.

150 tons. The Narwhal has a tusk that is an 8 ft. left tooth, found only in males.

The Blue whale is the largest animal - 100 ft. long,

_Beluga whales are pure white, Arctic whales called "sea canaries" because they vocalize so much.

6:23B _Dolphins are the most' social and intelligent whale.

-body temperature of 97.7 0 F

-7 minutes between breaths

-25 miles per hour swimming speed –

- River dolphins of South America cannot swim in a straight line

Whales (and all marine mammals) are protected by the Marine Mammals Protection Act of 1972. It was passed in response to purse-seine killing of dolphins in _ huge 4,000 ft. long nets. However, many are still being hunted to extinction under the guise of scientific research or areby-catch of the tuna fishery. 

There are over 1 million reported deaths per year. Tuna caught on lines is "certified" as dolphin safe by company employees.

International Whaling Commission (I.W.C.) is a whaler's organization that sets quotes based on catch size. They are not a regulatory agency and compliance is voluntary.

6:23CCetacean adaptations to marine life: Swimming: result of powerful tail flukes. Fluke markings are used like fingerprints for identification. Sei whales are fastest at 40 m.p.h.

Digestion: multi-compartmentalized stomachs "chew" food, (even toothed whales don't chew). Teeth are conical and unspecialized.

Baleen whales feed by jumping through pockets of plankton (called breaching).

their stomachs can hold 2 tons of krill at one time.

Toothed whales hunt in packs and seek out individual fish, penguins, seals, sharks or other whales.  Circulation: High blood volume holds maximum oxygen and glucose levels. Their veins are large enough for a trout to swim through them.Blood can be shunted to brain, heart, lungs and muscles and away from stomach and kidneys to protect vital organs.

4-chambered heart can transfer arteriole heat to the veins as blood flows toward the tail - called counter-current heat exchange.

6:23D Blubber insulates against cold. Overheating is solved by sending blood to surface tissues (flukes and fins) and by passing the countercurrent vessels.Whales in captivity exercise less and often lose the ability to cool off by straightening the fins.

Senses: Vision is poor in most species. Vocalizations and echo-location compensate.Whales have no vocal chords but make songs, clicks and whines by vibrations in the blow hole. 

They may communicate to1. indicate territories, 2. attract mates3. or act as homing devices for the young._Families of whales have their own dialect.

Sounds are emitted and amplified in the head through an oil filled cavity called a melon. Incoming vibrations are focused through the jaw and melon to the inner ear and the brain.

melon

The sounds are extremely accurate andVERY loud - can be used to stun prey.When whales enter the thermocline, sounds can be heard 1/4 of the distance around the earth.

Diving: Lungs are completely filled and emptied quickly through the blow hole on top of the head.

6:23E

A trachea under the blow hole connects directly to lung They can not breathe through their mouth and candrown unless the top of the head is exposed to air.

trachea

The nasal passage closes when relaxed to prevent water from entering the lungs, and allows them to sleep for short periods withoutdrowning. Whales can accumulate sleep._Some whales go to depths of 13,000 ft. and only breathe every 90 minutes - smaller species have less range. 0xygen is stored in the muscles.Ribs are collapsible to reduceinternal air pockets.

Excretory: Specialized kidneys allow whales to drink salt water. The urine is very saline.

Mating usually occurs in early summer. Implantation of the egg is delayed 4 months. Gestation lasts 7 months, so babies are born in warm summer months.

Many whales only have one calf every 2-3 years. Babies weigh from 200 pounds to 1 ton.

Mama and Baby say tootles. But stay tuned for some very important pictures of their friends

Right whaleSperm whale

Pilot whale Blue whale