1. Pinnepeds ("feather-footed") –Seals, Sea Lions, Walruses –Habitat: polar, midlatitudes –Require shore and/or sea-ice areas OTHER MARINE MAMMALS

2. Sea cows -- Manatees, Dugongs: tropical herbivores OTHER MARINE MAMMALS

3. Sea otters Habitat: cold, coastal waters Nutrition: carnivores of benthos OTHER MARINE MAMMALS

Few species, but successful Representatives: TurtlesTurtles CrocodilesCrocodiles SnakesSnakes Marine IguanasMarine Iguanas MARINE REPTILES

WHY MIGRATION? Migration links regions appropriate for reproduction... regions of feeding for adults And... Food resources change seasonally Examples: California Grey Whales- Mexico to Alaska MIGRATION OF NEKTONIC SPECIES -- SOME NOTABLE EXAMPLES -- SOME NOTABLE EXAMPLES

More Examples: Pacific Salmon- fresh water spawning Atlantic Eels- salt water spawning- opposite Atlantic Green Turtles- nesting sites vs. foraging

Class 37 BENTHIC COMMUNITIES Intro: Great Diversity Intertidal (rocky coasts) Mud and sand bottoms Deep-sea Hot-spring vents

Diversity related to wide range of conditions: 1.Availability of food varies 2.Nature of seafloor (sediments, rocks, etc.) varies 3.T, S, turbulence, exposure to air vary Vast majority of animal species in the oceans are benthic- Why?

Some places very rich....

Undisturbed deep sea bottom at approx m water depth in the Peru Basin. The picture shows a sea cucumber (Psychronaetes hanseni) and a stalked sponge (genus Hyalonema) among manganese nodules. OFOS photograph taken during cruise SO 61 in 1989.

HabitatNutrition Epifaunalfilter-feeders, predators Infaunaldeposit feeders, filter-feeders Few predators

Highly variable physical conditionsHighly variable physical conditions Diverse and productive communitiesDiverse and productive communities Different species in different depth zonesDifferent species in different depth zones –Reflects differing environmental stresses COMMUNITIES ON ROCKY SHORES

Rocky shore zonation

Typical inhabitants –Lichens + small (green) algae (few) –Herbivorous snails, clams, limpets –Filter-feeding barnacles All adapted to rough, occasionally dry conditions Most have shellsMost have shells Supratidal

Supratidal

Intertidal inhabitants Attached brown algae Herbivorous limpets and chitons Filter-feeding clams and other molluscs

Intertidal

Subtidal inhabitants Variety of attached, large algae Good environment- sunlight! No roots- holdfasts Herbivorous sea urchins Molluscs Predatory sea anemones and starfish

Subtidal

Kelp Forest Ecosystem Kelp => Sea Urchins=> Sea Otters

Sediment bottom is unstable --> Few large, attached plants --> Few grazing animals Organic matter comes from: Other environments Other environments Planktonic algae Planktonic algae Sand beaches -- sparse organic matter in sediments SEDIMENT-COVERED (MUD AND SAND) BOTTOMS

Soft-sediment Zonation

Soft-sediment organisms (most are infauna- protection, esp. at low tide)

less turbulent water than sandy beachesless turbulent water than sandy beaches finer sediment grain sizefiner sediment grain size greater accumulation of organic mattergreater accumulation of organic matter -- O 2 -free conditions at depth Mud flats - - more protected environments

Animals that utilize degraded plant material (in water or sediment) are dominant -- Deposit/detritus-feeders But also filter feeders predators Mud flats - - more protected environments

Polonices = Moon snail Shell driller

Environmental characteristics: –Uniform water conditions (cold!) –Fine-grained sediments –Limited food- not many animals Deposit-feeding infauna are dominant: –worms, burrowing crustaceans, sea cucumbers -- This jumbles the record in the sediments Suspension feeders and epifaunal scavenger- predators- much less abundant (fish, starfish, crustaceans) DEEP-SEA COMMUNITIES

Undisturbed deep sea bottom at approx m water depth in the Peru Basin. The picture shows a sea cucumber (Psychronaetes hanseni) and a stalked sponge (genus Hyalonema) among manganese nodules.

HYDROTHERMAL VENT COMMUNITIES SEEP COMMUNITIES Food-producers: chemosynthetic bacteriaFood-producers: chemosynthetic bacteria Diverse and exotic benthic communities:Diverse and exotic benthic communities: - crustaceans - clams - molluscs - fish - enormous tube worms with red flesh

DescriptionDescription Corals and symbiosisCorals and symbiosis Coral Reef architectureCoral Reef architecture ThreatsThreats Class 38 CORAL REEF COMMUNITIES

Coral Reefs Diverse and productiveDiverse and productive Thousands of invertebrate and vertebrate speciesThousands of invertebrate and vertebrate species “Rainforests” of the marine world“Rainforests” of the marine world

Coral Reef

Related to Jellyfish and Sea AnenomesRelated to Jellyfish and Sea Anenomes Colonies; individual polyps with tentaclesColonies; individual polyps with tentacles -predators and filter feeders. Coral animal -- dominant reef-builder

Individuals secrete supporting "cup" of CaCO 3 (grow up to 10 cm per year!) Variety of growth forms --Variety of growth forms -- massive, columnar, branching, etc. Coral animal -- dominant reef-builder

T: >18˚C… ˚ is best --> mostly low latitude, mostly low latitude, < 30˚ N or S S: cannot be low (e.g., near rivers) Depth: Photic zone, cannot grow deeper than m Clear water (little suspended sediment, phytoplankton) Environmental requirements of growing coral reefs: growing coral reefs:

Symbiotic algae provide much food Tentacles capture additional food Coral Nutrition