ZooplanktonFall 2006

PlanktonPlankton Classification

PlanktonPicoplankton (0.2 2 m)Nanoplankton (2-20 m)Microplankton (20-200 m)Mesoplankton (200-2000 m)Macroplankton (>2000 m)Net-planktonPlankton Classification

PlanktonHerbivoreCarnivoreOmnivoreDetritus Producers

PlanktonBacteriaPhytoplanktonZooplankton

PlanktonVirusesBacteriaPhytoplanktonProtozoaZooplankton

ZooplanktonDrifting animals, organisms that eat other plankton

ZOOPLANKTONAnimals that can swim and pursue prey.Radiolarians, ForaminiferansCrustaceanCopepodsGelatinousSalps, larvaceans, ctenophores, jellyfish, pteropodshttp://pandora.ucsd.edu/jaffelab/people/celeste/Intro/

Why study them?Most abundant animal on earthSecondary producers in marine systemsFound in nearly every imaginable habitatCritical step in marine food chainsEarly life-stages of important commercial fish, shellfishImportant in nutrient cycling

Important Zooplankton GroupsSubclass CopepodaCalanoideHarpacticoidsCyclopoidsSub-Phylum TunicataLarvacea (pelagic appendicularians)Thaliacea (salps, doliolids, pyrosomas)

CopepodsPhylum ArthropodaClass Crustacea

Hard exoskeleton (chitin)MoltJointed appendages1 simple eyeSmall (0.2 mm - >1 cm)Fecal pellets with a peritrophic membrane

TunicatesSubclass AppendicularianSubclass SalpSubclass Doliolids

Gelatinous, soft bodies carbohydratePelagicPump water through filter netsChordates (simple nervous system)Feed on a large size range of particles

Copepod-Images

Copepod-images

Gelatinous-images

Gelatinous-images

Gelatinous-images

Gelatinous-images

Other Zooplankton-images

Biological Carbon PumpEuphotic DepthDOC

GrazingClearance Rate = Grazing Rate: volume of water from which particles are completely removedEfficiency: percent of particles remove (usually based on food quality or size)Filtration Rate: total volume of water passing the filter apparatus per unit time1 copepod filters 1 l of water per h and that water has in it; 5 50 um particles/l100% efficiency - 10-20 um particles/l100%50-2 um particles/l 10% Clearance rate = 300 ml /copepod / h

Grazing (continued)Ingestion Rate: amount of food passing through the gut per unit timeUnits of chl, C or N

Filtration rates are related to food concentrationFilterrateFood Conc.

Filtration Currents

Retention SizeDetermined by the distance between the setae on maxillae of copepodsCarnivores >> herbivores /omnivoresDetermined by the net spacing in tunicates

Efficiency Example

Grazing TypesFiltration: nonselective feeding, based on water currentsRaptorial: may or may not be selective: grab a food itemMechanical receptionChemosensory

Limitations / Preferences for GrazingSizeNutritional contentTasteConcentrationSpeed

Diel Copepods: increased feeding at nightTunicates: may or may not be diel

SeasonalMaximum in the springTemperate areas (spring, fall, summer, winter)Polar areas (spring, summer, fall, winter)Food supply (concentration and type)Life cycle of the zooplankter

Seasonal GrazingSpringSummer

Methods for GrazingClearance ExperimentsChange in the number of cells during an incubationGut PigmentGrazing on phytoplankton (depends on pigment destruction)TracersFluorescent-labelsMicrocapsulesC-14, H-3 thymidine

Examples of Grazing Methods

ZooplanktonCOPEPODSProtozoaPhytoplanktonDetritus GELATINOUSDOMColloidsBacteriaProtozoaPhytoplanktondetritus

Particles for Export and FoodWhat types of particles?Feeding AppendagesWebs, housesGelatinous ZooplanktonFecal Pellets

ExcretionRelease of soluble materialAmmonia (Urea, free amino acids, DOC)Younger stages excrete more per unit weight (Not total volume)Decreases with temperatureRelated to grazing

Egestion: Fecal pellet productionRelease of solid materialHigh 7-17 C:NCopepods: surrounded by peritrophic membraneDepends on food concentration to a pointLinear relationship between ingestion rate and pellet production rateTemperature dependentFPPR /PelletVolumeFood Conc

Comparison between Copepods and Tunicates

Major Avenues of Focus TodayControls on toxic bloomsGrazed or not?Carbon cycle Global warmingGrazing and flux of fecal pelletsBiodiversityGenetic studiesExtreme environmentsHuman Health

Major Programs AroundEurapp (European Appendicularians)JGOFS (Joint Global Ocean Flux Study)TASC (Trans-Atlantic Study of Calanus finmarchicus)GLOBEC (Global ocean Ecosystem Dynamics)

MethodsNets1-sizeMultiple size meshMultiple net framesAcousticsCamerasIn situVideoLaserDivingSubmersiblesFluorescence

Methods-ExperimentsElectrodesChemical AnalysisMolecular techniquesComputersInternet

Zooplankton EcologyWho is there?What are they doing?How are they doing it?

Before we start: take out a piece of paper and take 2 minutes to write down what you would like to learn and get from this class.

Id like to take a few minutes to describe the course as I see it and what my goals are.The first is by life cycles. Holoplankton live their whole life in the water while Meroplankton live only a portion of their life in the water.Holoplankton is the focus of this courseThe first is by size or more the functional role of the organisms. This type of classification cuts across all groups. The largest group here the macroplankton is on the boarder line of the classical definition of plankton as many of these organisms can swim against water currents. It is with these larger size categories that definitions can get fuzzy..The second is by the functional role of the organisms. This type of classification cuts across all groups. The largest group here the macroplankton is on the boarder line of the classical definition of plankton as many of these organisms can swim against water currents. It is with these larger size categories that definitions can get fuzzy..The third approach is to group organisms according to morphology/taxonomy (kingdom/phyllum)Initially there were three divisions (bacteria, phytoplankton, zooplankton)prokaryotic cells that did not have their DNA in a nucleusphytoplankton:plantszooplankton:animalsToday: we have added a few more groups (protozoa and viruses)

This course is focusing on these four groups, primarily though viruses will be discussed.Included in this group are larvae of larger animals Copepods are raptorial filter feeders munch and break their foodImportant in carbon cycling?Food for whales and fishMany Gelantinous are filter feeders (pico to micro sized food) can be very important in vertical flux.Important food source for many commercial fishHard to work with so relatively little is knownAim of this class is to give you the basic building blocks to understand these questions and to address them. I cant cover everything and there are whole topics not being covered but hopefully this class will provide you with the basics to step off into the wider and exciting field of zooplankton ecology.