Marine Habitats What is a marine habitat? Where do we find (different) marine habitats? Water quality parameters that effect life? Who lives there (marine organisms and their necessary adaptations)? Marine Ecology (intro.)

Ocean Habitats

The benthic environment is divided by depth into the: –intertidal (littoral) zone –subtidal (sublittoral) zone –Epi, Meso, Bathyal & Abyssal zone(s) –(other) hadal zone The pelagic environment is divided broadly into the: –neritic zone –oceanic zone More specifically into the: –Epipelagic zone –Mesopelagic zone –Bathypelagic zone –Abyssalpelagic zone –hadalpelagic zone There are two major marine provinces: –the benthic (bottom) –the pelagic (water column)

Figure Marine zones

PELAGIC ZONES: “water column” (1) Oceanic – beyond shelf break (2) Neritic – area that lies over shelf Then this is divided vertically by depth: (1) Epipelagic: shallowest (w/ lots of light) (2) Mesopelagic: below (minimal light, no primary production, “twilight zone”) (3) Bathypelagic, Abyssopelagic, Hadopelagic: at bottom (no light, “deep sea environment”) ORGANISMS THAT LIVE IN PELAGIC ZONE ARE IN WATER COLUMN ONLY = PLANKTON and NEKTON

Each zone is different Light Temperature Salinity Other: Turbidity/Water Clarity/Sedimentation, Dissolved Gases (such as Carbon Dioxide), pH (ocean acidification), Pressure etc. These are considered “Water Quality” parameters (as they effect the quality of the seawater that serves as “home” for so many marine organisms)

What does this mean to MARINE LIFE? Light effects WHERE plants and animals can live. Temperature effects WHERE plants and animals can live. Salinity effects WHERE plants and animals can live. …WATER QUALITY PARAMETERS determine the “health” of the environment marine organisms live in.

Light Differences

The ocean can also be divided into zones based upon depth of light penetration. –The photic zone is the depth where light is sufficient for photosynthesis. –The dysphotic zone is where illumination is too weak for photosynthesis. –The aphotic zone receives no light from the surface because it is all absorbed by the water above.

In the dysphotic zone, seasonal effects are minimal – conditions tend to be uniform most of the year. The aphotic zone is permanently dark and cold. –It contains many unique midwater fishes. Fnft: Midwater Fishes

Fig , p. 285

Fnft: A spatial classification of marine organisms

Figure 3.11

Light penetration is different, based on: –Levels of photosynthesis/primary production. –Water quality/sedimentation/turbidity –Location: proximity to shoreline.

In turbid coastal waters light rarely penetrates deeper than 20m. –The water appears yellow to green because particles reflect these wavelengths. Fnft: Yangtze River

Light Penetration Dictates how a species can grow Picture 1 is “shallow” subtidal coral – notice “raised” edges Picture 2, much deeper down, shows a coral that is FLATTENED (like a solar panel!) to “catch” as much light as possible in deeper waters This is SPECIES ADAPTATION!

Figure 10.1a

Figure 10.1b

Temperature Differences (these are certainly associated with light)

Properties of Seawater Light and Temperature in the Sea The range of biologically important temperatures at the Earth’s surface.

Temperature relationships in different ocean environments

Water temperatures (surface) worldwide

Fnft: Earth's sea surface temperatures obtained from two weeks of satellite infrared observations July Temperatures are color coded, with red being warmest and decreasing through oranges, yellows, greens, blues, and black. Properties of Seawater Light and Temperature in the Sea Image courtesy MODIS Ocean Group, NASA GSFC, and the University of Miami

Temperature can control aspects of an organism’s life: –distribution –degree of activity –Reproduction Barnacles

…Combined… Light Temperature = Global Climate Change

Properties of Seawater Light and Temperature in the Sea: Our Planetary Greenhouse Pattern of atmospheric CO 2 increase over five decades. The slight annual variations are due to seasonal CO 2 uptake and release by land plants. Reproduced from Robert A. Rohde.

Other water quality parameters (these are certainly associated with light and temperature) -- Salinity -- Dissolved Gases (pH/ocean acidification, carbon dioxide etc.) + Summary of all together included

Properties of Seawater Geographic variations of surface ocean salinities, expressed in parts per thousand (‰). Ocean Salinity

Properties of Seawater Dissolved Gases and Acid-Base Buffering The pH scale, showing the concentration of H + ions at each pH value. Note that the concentration scale is exponential.

The CO 2 System Gases in Seawater

Pressure Water is heavier than air Pressure changes ( a lot!) w/ increased water depth 1 atm. of pressure = sea level (on land) but in ocean each 10 m of depth (33’) you add another atm. of pressure

Figure 3.13

Combined… These give us a “3 layered” (stratified) ocean (based on depth) and specific areas for our unique marine habitats to exist. Coral Reefs don’t grow in the Arctic (why?) and Mangrove Forests aren’t found in the Arctic (why?) Everything has a “place!”

Fig. 3.22

Figure 3.17

Ocean Conveyor “Belt”

What grows where? Image courtesy MODIS Ocean Group, NASA GSFC, and the University of Miami Temperate vs. Tropical vs. Arctic Marine Habitats; examples include: Coral Reefs, Kelp Forests, Polar Seas, SAV Beds, Estuaries, Mangrove Forests etc.

Who lives in these zones?

The Domains of Life

Marine organisms can also be classified by lifestyle Plankton float in the water and have no ability to propel themselves against a current. –They can be divided into: phytoplankton (plants) zooplankton (animals) Nekton are active swimmers and include: –fish, –Reptiles –mammals –birds Plankton - Larvae

Figure Plankton (sorted by Size)

Nekton have the ability to swim against currents. –They can actively search for a hospitable environment. –Many fish school, which is another form of patchiness. School of Fish

Figure 10.11

Major pelagic sediments in the ocean are red clay and biogenic oozes. “Marine Snow” Foraminifera Diatoms

Plankton vs. nekton AND Benthic vs. Pelagic

Benthic organisms live: –on the bottom (epifauna) –within the bottom sediments (infauna) Some organisms cross from one lifestyle to another during their life, for example being planktonic early in life and benthic later. Flounder, a bottom fish

A Benthic Community

The water column is shallow in the sublittoral zone. Bottom energy is a function of: –wave energy –tidal current Bottom energy at the sea bed diminishes as distance from shore increases. Benthic zone properties/sedimentation

The sea floor can be divided into high energy environments and low energy environments. Figure 13-5a Bottom energy affects organisms by: –moving sediment around –creating an unstable substrate –controlling sediment size

Shelf Sedimentation

Physical factors regulate the number, type and distribution of benthic organisms. –The two major benthic communities based upon substrate are: Soft-bottom communities are typified by unconsolidated sand and mud substrates. Sandy areas harbor filter feeders whereas deposit feeders dwell in muddy regions (e.g. estuaries/beaches). Hard-bottom communities are typified by rock and gravel substrates. Seaweeds occur here and the animals tend to be filter feeders, grazers, and predators (e.g. Coral Reefs and Kelp Forests). ©Ablestock.com

If you’re not benthic you’re… PELAGIC! A “Pelagic community” is a community of organisms that live suspended in the water column…they either float (plankton) or swim (nekton). This is different than those that live on shore, on the bottom (etc.)

Pelagic Communitiy, Plankton And nekton

Bony fish (pelagic species) examples

Marine Mammals that live in the pelagic zone (Baleen)

Marine Mammals that live in the pelagic zone (Toothed)

Other examples… PELAGIC vs. BENTHIC ORGANISMS in some of the habitats we’ll study this semester

Top predators in the open ocean are: –Mackerel –Squid –Jellyfish –Tuna –Porpoise –Shark –Humans Squid Tuna Shark Jellyfish Pelagic

Pelagic: Dinoflagellate (A unicellular planktonic algae)

And who eats it…a Whale Shark (pelagic)

Pelagic

pelagic

Pelagic: Hawksbill Turtle

pelagic

…benthic

Kelp (an algae) Giant Kelp Community

Sea Urchins in a Kelp Forest Understory

Hermit Crab

Benthic (cone snail eats Goby)

Benthic: barnacle and Littorina (snail)

Blue Ringed Octopus on coral

“Combo” examples and those that fly…

BOTH! (but benthic right now)

pelagic

Pelagic (w/ benthic attached!)

Important seabirds include: Puffin Albatross Little Blue Penguin

Many birds, such as wading shore birds, have bill shapes that have evolved due to their foraging style (in the BENTHIC habitat).