Interactions

• cooperation vs. competition for resources
• different trophic levels incorporated:
  • producers, decomposers, and nutrients
  • consumers
    • herbivores are primary consumers
    • predators are secondary and above
    • parasites and scavengers
• predator-prey relationship: one organism captures/ingests the other organism
  • food chains are strands of food webs which involve several predator-prey relationships
  • food webs are complexes of predator-prey relationships

Predation

• Protists: Paramecium and amoeba, paramecium and yeast
  • sweeping food to engulf, phagocytosis
• Fungi: Arthrobotrys fungus and nematode worms; constricting, capturing, and digesting prey through infecting hyphae
• Carnivorous plants: Venus flytrap, Sundew, Darlingtonia pitcher plant
  • seeking nitrogen in nitrogen-poor environments
  • digestive enzymes to break down insects
  • triggers and sticky substances to capture insects
• Animals: Hydra and Daphnia
  • Cnidaria and Crustacea
  • Nematocysts, poison dart-like, neurotoxins and capture

Avoiding Predation

Camouflage

• Concealing/Disruptive Coloration
• With regard to environment
• Biston betularia and bark; light/dark morphs

Warning Camouflage

• Warning/Aposomatic Coloration
• Poison dart frogs, tomato frogs; high toxicity/gummy toxicity

Mimicry

• Can be through appearance, behavior, sound, or scent
• Batesian: a palatable, harmless creature mimics a harmful/noxious species
  • Parasitic mimicry
  • Coral Snake (Venomous) vs. King Snake (Batesian); Monarch and Viceroy butterflies
• Müllerian: various animals which are noxious/harmful share characteristic appearances for protection and mutual benefits
• Defensive Mimicry:
  • Caligo martia verso, butterfly; eyespots resemble owls
  • Hemeroplanes triptolemus, caterpillar; rear eyespots resemble snakes

Symbiosis

Mutualism

• Both partners benefit
  • Lichens
    • Fungi provide moisture and nutrients, protection, anchorage
    • Photobiont produces sugars and photosynthesizes
  • Sharks and remora
    • Remora consume shark parasites, sharks protect and transport remora
  • Termites and protists
    • Termite guts digest cellulose; Bacteria, Archae, Eukarya Trichonympha
  • Rhizobium and Fabaceae
    • Pea plant nodules shelter bacteria
    • Rhizobium is nitrogen-fixating

Commensalism

• One organism benefits, the other is unaffected
  • Innkeeper worms and pea crabs
    • Urechis sp. creates a tunneling system and pumps water through burrow
    • Pea crabs, Polychaetes, Arrow goby
  • Barnacles and whales
    • Filter-feeding plankton predative arthropods
  • Oak galls and cynipid wasps
    • Cynipidae wasps create oak galls that shelter from parasites and environment

Parasitism

• One organism benefits, the other is harmed
  • Tapeworms and vertebrates: Parasites that don’t kill host
    • Parasitic cestoda
    • Underdone/raw pork
    • The oncosphere or hexacanth was not designed for frolic, his part may be described perhaps as coldly diabolic….
  • Spider hawks and spiders: Parasitoids that kill host
  • Dodder plants
    • Parasitic; takes/shares minerals/nutrients
  • Mistletoe
    • Partial parasites: able to photosynthesize
    • Absorbs water/nutrients from a host plant
  • Tarantula hawk: Pepsis, Hemipepsis
    • Stings and paralyzes tarantula, captures, lays egg in abdomen and larvae emerge after maturing to adults
    • Parasitoids
    • Large stinger
    • Aposematic coloration, open behavior

Co-evolution

• Two or more species are linked in a way that genetic changes in one species influence the other’s in evolution
  • Predator-prey, Host-parasite, Flower-pollinator
• Angraecum sesquipedale and thin proboscis of Xanthopan morgani
  • Darwin’s Orchid Book, 1862; Fertilization of Orchids
  • 12” long spur with waxy setae
  • Darwin’s Hawk Moth

Allelopathy

• Organisms producing chemical toxins (allelochemicals) that reduces germination of competing species
• Manzanita, chamise, eucalyptus compounds; menthol

Freshwater Aquatic Communities

• Limnology: the study of freshwater aquatic communities: lakes, ponds, wetlands, rivers, streams
  • limne: Greek, marsh
• Mono Lake is high salinity (2x Pacific Ocean); few species

Various Trophic Levels

Producers

Bacteria and cyanobacteria

• Anabaena spp. : photosynthesis, nitrogen fixation, neurotoxins
  • Nitrogen gas makes up about 78% of atmosphere and dissolves in water
  • Anabaena can cause taste/odor problems in lakes used in recreation and drinking water; Anabaena blooms

Protists

Algae

• Spirogyra spp.
  • “Pond scum”
• Closterium
  • Crescent-shaped algae
  • Desmid
  • Mucilage secreted to perform a somersaulting motion in transportation

Diatoms

• Bilateral symmetry
• Pelagic, benthic
• Biofilm
• Used in filtration, as abrasive, and as drying agent

Dinoflagellates

• Reproductive cysts
• Neurotoxins; red tides
  • Paralytic Shellfish Poisoning
  • Seasonal shellfish bans
  • Gonyaulax releases saxitoxin (STX)
    • Mussels and oyster predators are affected
    • PSP → humans, dogs, marine predators
      • Dizziness, numb lips and neck, fatigue, difficulty breathing, asphyxiation
    • STX is 1000x more toxic than sarin nerve gas
    • Used in 1950s CIA suicide pills; destroyed in Nixon presidency with UN Agreement on Biological Weapons
    • STX is one of 2 natural toxins on Schedule Chemical Warfare Agents list
• Peridinium and Ceratium spp.
  • Peridinium: peridinin thick armor plates
  • Ceratium: armor with horns
• Glenodinium, Gymnodinium, Gonyaulax
• “Whirling whip”

Plants

• May be emergent, rooted floating, non-rooted floating, or submerged vegetation
• Growth is limited by various key factors:
  • Availability of nutrients
    • Roots grow in murky bottom for nutrients
  • Availability of light for photosynthesis
    • Shoots grow aerial
    • Sunlight cannot fully penetrate deep water; some is reflected by the surface, some absorbed by algae, some reflected by the suspended sediment (soil)
• Used as shelter for small fish and invertebrates; fish prey on invertebrates sheltered in plants
• Wading birds such as Great Blue Herons stab at moving vegetation to obtain small fish and crayfish
• Gut content analysis and SCUBA observation data: larger fish move into open water

Streamside/Riparian

• Equisetum spp.
  • Horsetail
  • SVP
  • Sandy river banks and levees in Sacramento
  • Stiff, jointed stems reinforced with silica that can be pulled apart
  • “Scouring rush”; dish cleaning
• Carex spp. and Cyperus spp.
  • May also be emergent
  • “Sedges have edges and rushes are round”
  • Triangular
  • Sedges
  • Streams and wet areas
  • Perennials
  • Spreading rhizomes
  • Roots used for native basketmaking
• Populus fremontii
  • Fremont cottonwood
  • 40-90’ tall
  • Streams and rivers on Sacramento Valley and foothills
  • Younger trees: smooth bark
  • Older trees: cracked white bark
  • Heart-shape leaves with long tips and flat leaf stalks
    • Flutter easily from wind
  • Wind-dispersed seeds; cotton appearance while flying and accumulating
• Salix spp.
  • Willows
  • 40+ species/variants
  • Long, narrow, pointed leaves
  • Found along streams or pond banks
  • Spring-blooming flowers; bloom before leaves
  • Dioecious
  • Bark contains salicin: salicyclic acid (aspirin)
  • Stems eaten by deer, elk, beaver, etc.
  • Leafy branches used as shelter and food for birds
• Rosa californica
  • Wild rose
  • Moist soil, including riparian areas
  • Dense shrub; 3-9’ tall
  • Compound leaves with toothed leaflets and stiff hair on undersides
  • Bloom from May–November
  • Rose hip fruits: bright red or orange, round
    • Vitamin C
    • Tea, jam, jelly, food
• Rubus ursinus
  • California blackberry
  • Common but not exclusive to riparian
  • Native
    • Seen alongside Himalaya blackberry
      • Himalaya has darker, wider, thick-thorned stems
      • R. ursinus has green, thin-thorn stems; trailing or climbing stems, dense thickets
  • Compound leaves with small thorns on undersides
  • Five white petal flowers
  • Shelter and prey for mammals, birds
  • Ripe fruits are black; unripe red
• Vitis californica
  • Climbing vine
  • Stream and river banks
  • Vines climb trees: oaks and cottonwoods common
  • 60’+ long, 5”+ wide
  • Late summer-early fall food
  • Small white flowers pollinated

Emergent

• Roots in mud substrate, but shoots grow aerially
• Bur-reed, water plantain
• Typha latifolia
  • Broad-leaved cattail
  • Perennial
  • Pithy stems
  • 7’ tall
  • Ornamental; leaves used for weaving mats and chair seats
  • Female flowers are brown, male are yellow; female found under male flowers
  • Edible underground rhizomes
  • Predated by muskrats, beavers; used for nesting by red-winged blackbirds
  • Wetlands
• Schoenoplectus acutus
  • Common tule/bulrush
  • Perennial
  • 6’ tall
  • Wetlands
  • Stems grown leafless; grown from creeping rootstocks
  • Scaly flowers bloom in summer
  • Predated by waterfowl and used as shelter/nesting for various wildlife
  • Used by Miwok for boats, mats and roof thatching, cooked and/or dried
• Juncus spp.
  • Rushes
  • Wet and moist areas
  • ~2-4’ tall
  • Clumped growth
  • Round, unjointed stems; may be hollow or pithy
  • Clustered small green or brown flowers on tops and sides of stems
  • Predated

Floating

• Leaves float on water surface, hydrophytic
• Rooted: Water lilies
• Non-rooted: Duckweed
• Lemna spp.
  • Small, non-rooted, floating
  • 0.5” stems hang down in water
  • “World’s smallest flowering plant”, “Floating green carpet”
  • May be intermixed with mosquito fern
  • Predated by ducks
• Azolla spp.
  • Aquatic ferns; seven species
  • Highly specialized for hydrophytic life
  • Mixed with duckweed
  • Mosquito fern
  • Symbiotic relationship with Anabaena
  • Can ideally double biomass every two days

Submerged

• All parts are underwater
• Requires water clarity; clarity determines depth due to amount of penetrating sunlight
• Elodea: waterweed/pondweed
  • submerged/open zone
  • flowers on surface
  • habitat for smaller prey and predated by primary consumers
  • Six species in genus
  • Aquarium plants
  • Native to Americas, invasive in UK
  • Multi-branched perennial that can grow in separated fragments
    • Flowering; Three white petals with a waxy hydrophobic coating
  • Used as habitation and decomposing food

1* Consumers

• Arthropoda phylum
  • Plankton
  • Phytoplankton
  • Zooplankton (2*)
    • In open water and rock/mud surfaces of freshwater
    • Predates unicellular diatoms and algae, separate filamentous algae

Crustacea

Cladocera

• Water fleas
• Downward angled head with a beak
• Two pairs of antennae
• Daphnia
  • May undergo chemical changes in response to predator cues in water: longer spines, enlarged “helmet”
  • Prominent spine
  • Stores eggs in a belly shape
• Simocephalus, Scaphloebris, Ceriodaphnia, Bosmina, Alona

Ostracods

• “Seed shrimp”
• Protected by a bisected hinged carapace
• Diverse; 8000+ species in freshwater and marine environments, planktonic or benthic
• 485mya old

Coleoptera

• Insecta
• Water scavenger beetles
• Fully aquatic lifecycle
• Good fliers
• Dark colors; smooth elytra
• Heavy bristles on hind legs
• Mostly herbivorous; benthic detritivores

2* Consumers

Crustacea

Crayfish

• Feather-like gills
• Two pairs of antennae
• Five pairs of legs
• Omnivores, scavengers, detritivores
• Streams, ponds, lakes
• Burrows in mud when water dries
• Native CA species: Shasta crawdad
  • Others are introduced
• Predated by largemouth and smallmouth bass, river otter, raccoon, large wading bird, some ducks

Copepoda

• Cylindrical body
• Single median compound eye
• Two pairs of antennae
• Zooplankton
• Lerneae parasites infect copepods
• Calanoid, cyclopoid, harpacticoid forms

Branchipoda

• Fairy shrimp and tadpole shrimp
• Vernal pools: small seasonal wetlands
  • Typically found in winter rain seasons
  • Hummock topography with underlying soil layers that prevent depth infiltration
  • Rich soil seed outline remains from vernal pool plant species
    • Small plants that leave a carpet of bright flowers in spring
  • More than 85% California pools destroyed via urban/agricultural expansion
• Small; 1’ or less
• Short lifespan in adulthood; 2 months
• Swims on back
• Eleven pairs of legs
• Drought-resistant, rehydratable eggs; can last for decades without water
• Algae, bacteria, protozoa, detritus

Insects

• Larvae: Stonefly larvae, mosquito larvae
  • Mosquito larvae are wrigglers, pelagic; respiratory tubes and skin diffusion of oxygen
• Usable for water quality; indicator species
• Plays roles as scrapers/grazers, shredders, collectors
  • Scraper/grazer: feeds on substrate algae; fly midges, mayflies, beetles, caddisflies
  • Shredder: desynthesizes detritus into fine particles; stoneflies and caddisflies
  • Collectors: feeds on fine particles in water columns; fan-like filaments; chironomoid midges and mayflies
• River continuum concept: Parts of a river at different elevations of land have different frequencies/dominance of aquatic insect functional groups/roles
  • High elevation, small headwaters: Collectors dominate > Shredders >> Predators > Grazers
    • High amounts of CPOM (Course particulate organic matter: leaves and twigs)
    • P/R < 1
  • Low elevation, wide rivers: Collectors dominate >>> Predators
    • High amounts of imported FPOM
    • P/R > 1
  • In between: Collectors dominate > Grazers >> Predators > Shredders
    • High amounts of CPOM, some imported FPOM (fine particulate organic matter)
    • P/R < 1
  • DOM: dissolved organic matter

Odonata

• Naiads: Dragonfly naiads, mayfly naiads, damselflies
  • Gills, not spiracles
• Benthic silt on streams
• Carnivorous; may feed on tadpoles and small fish
• Dragonflies and damselflies feed shooting out a labium: double-hinged lower lip
  • Folded against ventral side of head and thorax
  • Has movable teeth, sharp bristles, hooks
  • Impales and pins prey for mandibles

Trichoptera

• Caddisfly
• Larvae
  • Aquatic
• Silk protective cases glued by materials from local stream
• Some are collectors: silk net filtering food
• Some are scraper/grazers
• Caddisfly jewelry commissions by placing materials in aquariums

Diptera

• Mosquitoes
• Larvae
• “Wigglers”
• “Egg raft” laying
• Surface breathing with siphon tubes
• Filters unicellular algae, bacteria, and microscopic organisms in water column
• Instar development → molt into aquatic pupae; “tumblers”
  • Pupae does not feed

Hemiptera

• “Backswimmers”
• Water striders, water boatmen, backswimmers
• Water striders:
  • Slow-moving or standing water in ponds, lakes, streams
  • Brown top with silvery hydrophobic waterproof hairs on bottom
    • Increase surface area
  • Shorter front legs than back; modified to grasp
  • Middle and hind are stilt-like
  • Piercing mouthparts
    • Predate aquatic insects that resurface
• Water boatmen
  • Oar-like, long hind legs
  • Underwater swimmer
  • Fully aquatic lifecycle
  • Benthic predator: algae, protozoa, microorganisms
  • Captures a bubble of air under abdomen for oxygen; stays underwater for over 30 minutes
• Backswimmers
  • Similar to water boatmen
  • Swim on backs
  • Eat larger insect prey than boatmen

Chordata

Osteichthyes

• Eating snails and aquatic invertebrates
• Lepomis macrochirus
  • Bluegill sunfish in lakes
  • Introduced
  • 8”
  • Green body with dark vertical stripes
  • Low elevation ponds, lakes, reservoirs
  • Resource partitioning
    • Young sunfish found in lake margins eating small aquatic invertebrates and hiding in vegetation
    • Adults forage on benthic or eat open water zooplankton
  • Opportunistic feeders
  • Prefers aquatic insects; diet depends on geography
• Green sunfish in streams and lakes

3. Higher-Order Consumers

Chordata

Osteichthyes

• Bony fishes
• Larger fish reside offshore; smaller fish try to take shelter near shore under vegetation

Anadromy

• Anadromous
• Born in freshwater
• Spends lifetime in ocean
• Spawns in freshwater
• Examples: Central Valley Steelhead, Chinook Salmon, Lamprey
• Chinook Salmon
  • Migrates up American River between October–December; water temperature decreases
  • Female diggs redd nest in clean gravel
  • Male sprays milt sperm over eggs and female recovers with gravel
    • Gravel allows waterflow with dissolved oxygen
  • Eggs hatch in 2 months, spend 2-5 years in ocean, then return to spawn
  • Salmon cycle
    • Spawning
    • Gravel eggs
    • Alevin
    • Fry
    • Parr
    • Smolt
    • Adult king salmon
• Steelhead trout
  • Adults do not always die after spawning; may spawn multiple times
  • Rainbow trout migratory subspecies
  • Coastal streams, American River, Sacramento River
  • Folsom Dam and Nimbus afterbay dam collection

Catadromy

• Catadromous
• Born in ocean
• Spends lifetime in freshwater
• Spawns in ocean
• Eels; no native catadromous Californian fish

Warm-Water Fish

• Carp, suckers, catfish
  • Carp obtain algae, dead organic matter, small invertebrates on floor
• Gambusia affinis
  • Mosquitofish
  • Introduced
    • Native to central United States
  • 2” long
  • Control mosquito and midge larvae populations; Clear Lake (Lake County) vs. Clear Lake Gnat
    • Eats up to 100 larvae per day
  • Can tolerate wide ranges of environmental conditions
  • Upward mouth; surface feeder
  • Females are larger than males; live birth
• Sacramento Tule Perch
• Catostomus occidentalis
  • Sacramento Sucker
  • Native “sucker”: suctioning mouth and lips
  • 2’ long, 5lb heavy
  • Most California rivers
  • Bottom feeder: algae, worms, eggs, larvae, detritus
  • Sometimes found in cold-water; research shows faster growth/maturation in warm water
• Sacramento Blackfish
• Sacramento Hitch
• River Lamprey
• Ictalurus catus
  • White Catfish
  • Most abundant catfish in California
  • Introduced
  • Warm-water lakes, streams, ponds, delta
    • Dark, murky waters
  • Tough skin; no scales
  • Barbels with olfactory receptors
  • Bottom feeders and scavengers; nocturnal
• Ptychochelius grandis
  • Sacramento pikeminnow (“sq*wfish”)
  • Native
  • 3’ long
  • Toothless, protrusible minnow jaw with bladelike pharyngeal teeth deeper in mouth
  • Young feed on aquatic insects; adults feed on fish, crustacean, small shore rodents
• Micropertus spp.
  • M. salmoides: Largemouth Bass
  • M. dolomieui: Smallmouth Bass
  • Introduced sport fish (1859 or earlier in Southern California)
  • LM: Warm, shallow waters with abundant aquatic vegetation
  • SM: Clear, cool lakes and streams with large amounts of cover
  • Both found in Folsom Lake
  • Both eat aquatic insects in youth and fish/crayfish/ducklings/etc. in adulthood
• Cyprinus carpio
  • Carp
  • Introduced in 1870s
    • Invasive: Muddies waters, destroys vegetation, competes with game and native fish species
  • Slow-moving lakes, ponds, sloughs
  • Favors areas with silt/sand sediment and abundant aquatic vegetation
  • Omnivorous bottom feeders: worms, algae, insects, mollusks, crustaceans
  • Large boys

Cold-Water Fish

• Onchorhynchus mykiss
  • Rainbow trout
  • Spends entire time in freshwater
  • Only native trout to Sacramento
    • Brown trout is introduced
  • Prized sport fish
  • Planted by DFW
  • Feedback loops and factors cause differentiation between rainbow and steelhead

Actinopterygii

• Acipenser transmontanus
  • White sturgeon
  • Cold-water fish
  • Largest freshwater fish in North America (20’+ long, 1700+ lbs heavy)
  • May live upwards of 100y
  • Adults live in bays, deltas, estuaries, nearshore coasts
    • Southernmost spawning species of Sacramento–San Joaquin Delta
  • Bony plates: scutes; not scales
    • Cartilaginous
  • Barbels for locating food
  • Siphonous mouth that sucks in food
  • Young fish are benthic feeders of invertebrates; larger feed mainly on fish

Amphibia

• “Living in two ways”
• Moist, scaleless skin
• Loses water rapidly when drying
  • Skin glands to secrete substances to keep moisture
  • Noxious protective substances
• Human disturbance in Sacramento area
  • Insecticides
  • Wetland draining
  • Pollution of streams

Frogs

• Pseudacris regilla
  • Pacific Chorus Frog
  • 2” long in maturation
  • Tan, brown, green colors; may be spotted
    • Distinct eye-stripe
  • Ponds and wetlands in California
    • May also be found away from water
  • Suction discs
  • Loud spring calls; heard in parks
  • Feed on insects
  • Eaten by fish, snakes, wading birds
    • Tadpoles are eaten by aquatic insects
• Lithobates catesbeiana
  • American Bullfrog
  • Invasive to California
    • Native to eastern and central California
  • Largest frog in North America
    • Opportunistic feeder
    • High reproductive rate; up to 20,000 eggs
  • Rarely found away from water
  • Chytridiomycota vector
  • Tadpoles feed on algae and vegetation
  • Eaten by fish, wading birds, snakes, predators

Salamanders

• Ambystoma californiense
  • California Tiger Salamander
  • Near vernal pools in California
    • Impacted
  • Glossy black adults with creamy white-yellow spots
  • Breed in spring; eggs laid in vernal pools and standing water
  • Aquatic larvae with external gills
  • Largely terrestrial in adulthood; shelter in burrows (California Ground Squirrel burrows)
  • Hatchlings eat zooplankton
  • Larvae eat invertebrates and tadpoles
  • Adults eat insects and invertebrates
  • Eaten by aquatic fish, frogs, birds, and terrestrial snakes, birds, skunks

Toads

• Various characteristics vs. frogs
  • Less tied to water than frogs, but need it for reproduction
  • Better adapted to dryness
  • Walk more than hop
• Anaxyrus boreus
  • Western Toad
  • Breeds in spring-summer in small ponds and temporary standing water
  • 300-500 eggs laid in long strands on aquatic vegetation
  • Tadpoles eat algae and detritus
  • Adults eat arthropods mainly
  • Eaten by snakes, coyotes, some birds

Reptilia

Clemmys marmorata

• Western Pond Turtle
• Found in rivers more than ponds
• Only native turtle of west coast
• “Species of special concern”, endangered
  • Habitat loss
  • Competition via introduced red-eared slider
• Omnivorous: Tule and cattail roots, aquatic invertebrates
• Predated by raccoons, river otters, ospreys, coyotes
• Eggs laid away from water

Trachemys scripta

• Red-eared slider
• Introduced
  • Native to central and eastern United States
• Popular pets; introduced into waterways via dumping
• Competitive for food, basking space, nesting

Aves

Megaceryle alcyon

• Belted Kingfishers
• Robin-size birds
• Large heads, notable crest, short tail
• Female chestnut-color band on belly and flanks
• Perching observing food, then dive into water to catch fish and crayfish
• Horizontal burrow nests in water banks
• Rattling call
• Eaten by mammals, snakes, hawks

Ardea herodias

• Great Blue Heron
• 4’+ tall, 6’ wingspan
• Blue-grey back and wings
• White head with a black plume
• Heron pulls in neck and trails feet to fly
• Sacramento area year-round; wetlands and rivers
• Spear-like beak: opportunistic feeders
  • Fish, snakes, small mammals, amphibians, crustaceans
• Predated by crows and raccoons in egg
• Large platform stick nest colonies

Ardea alba

• Great Egret
• 3’+ tall, 4’+ wingspan
• Spear-like yellow bill
  • Stalking and diving
  • Diverse diet: fish, amphibians, invertebrates, reptiles, small mammals
• White feathers
• Black legs and feet
• Sacramento wetlands, open fields, streams and rivers
• Eggs and young birds predated by raccoons, owls, hawks
• Egret feather plumes in breeding season prized for antique womens’ hats

Mammalia

Carnivora

• Lutra canadensis
  • River otter
  • Wetland and rivers in Sacramento
    • Suisun Marsh, Vacaville
  • Skillful, playful
  • 4’ long including tail, 25lb
  • Otters born in burrows or hollows in trees
  • Otters in family groups
  • Crayfish, waterfowl, muskrats, mice, lizards
  • Land predators: coyotes, bobcats, mountain lions

Rodentia

• Castor canadensis
  • Beaver
  • Largest California rodent
    • 100lbs (30-40 more common)
  • Large, flat, hairless tail
    • Slap water when disturbed
  • Orange incisors
    • Strip bark, clip twigs, cut trees
  • Former extirpation from local area due to beaver fur trade; now mostly recolonized
  • Eat bark, twigs, tules, plants
  • Predated by coyotes, foxes, mountain lions
• Ondatra zibethicus
  • Muskrat
  • Introduced
    • Introduced for fur
    • Escapees from fur farms → introduction
  • Half-grown housecat size
  • Partially webbed hind feet
  • Two glands secrete musky substance in breeding season
  • Herbivorous: Aquatic vegetation; cattail, tule, waterweed, rushes
    • Also freshwater clams and crayfish
  • Predated by mink, coyotes, bobcats, eagles, large hawks, owls
  • Nests in burrows in soft banks or reed-stick shelters above water level

Decomposers and Detritivores

• Decomposers occur adjacent to all trophic levels

Aquatic Plant Zonation

Emergent Zone

• Emerges from water
• Shoreline or close to shore

Floating-Leaved Zone

Submergent Zone

• Plants and algae submerged and rooted to substrate; in water column

Deep Water/Open Zone

Marine Ecology

Physical Features

• Oceans cover ~70% earth surface
• Continuous physiology, without geographical boundaries
• Continuous air circulation from winds and currents
  • Temperature range of pole and equator
  • Earth rotation
• Coriolis Effect
  • Currents run CW in northern hemisphere
  • Currents run CCW in southern hemisphere
• Coastline of CA has abundant sea life and biodiversity
  • Indentations on coastline: surface area is ⅓ of NA
  • Different temperature variations
  • Interdependent ecosystems
  • North Coast, SF Bay, Central C., South C.
  • Upwelling is caused by the North Pacific Gyre current
• Primary Productivity
  • Photosynthesis
  • Almost all photosynthesis is performed by algae, bacteria, and archaea

Subtidal Environment

• Beyond lowest tides; ~200m deep
• Influenced by wave surges
• Upwelling; most productive environments

Continental Margin

• Continental terrace, slope, and rise; not abyssal plain
• Causes deep channels
  • Monterey Bay, Cordell Banks

Marine Zonation

• Photic zone is at 200m or lesser below sea level; aphotic is above 200m; longitudinal zones
• Littoral: Non-pelagic lateral zone; High tides, continental terrace
• Pelagic: Encompasses neritic and oceanic territory (all marine territory), lateral to surface
  • Neritic: continental slope downwards, before abyssal plain
    • Sublittoral lateral zone
  • Oceanic: abyssal plain, deeply submerged substrate
    • Bathyal, abyssal, hadal lateral depth zones
      • Hadal: deep-sea trenches
• Various longitudinal zones based on depth
  • Epipelagic: photic
  • Mesopelagic: 200-1000
  • Bathypelagic: 1000-4000
  • Abyssalpelagic: 4000-10000m

Sandy Beaches

• Soft bottom substrates
  • Gravel, sand, shells
  • Little permanent surface to attach
  • Most burrow into sand; affected by wave action
    • Buffer zones for coastline, cliffs, and dunes
• Ice-free coastlines
• Lower diversity than rocky shores

Estuaries

• Freshwater from rivers intermixed with saltwater from ocean
  • Major influence is ebb and flow of tides
    • Constant change in salinity
• Protected from wave action

Salt Marsh

• Salt-tolerant growth: pickleweed, eel grass, cord grass
• Algae, diatoms
  • Enteromorpha, Gracilaria
• Salt marsh harvest mice

Mud Flat

• Non-vegetative area
• Underground/burrowed growth
  • Food particles are pumped through burrows or siphoned from surface

Rocky Intertidal

• Hard substrate, attachment
• Blown out sand, rooting; holdfast/foot attachment instead
• Four main zones based on exposure to wave shock and desiccation
  • Wave action countered by sheltering, holdfasts, low growth, muscular feet, byssal threads, suctions, thicker shells, flexibility
  • Dessication countered by sheltering, “clamming up”, careful anchorage in moist/shaded environments, thick shells, clamping, operculums, high desiccation tolerance
• Additional stress from heat, high-intensity light, UV light, hypersalinity, freshwater hyposalinity, wind

Splash Zone

• Limpets and periwinkles, rock louse, gulls and shorebirds (wandering tattlers, surfbirds)
• Above high-tide line
• Water sprays

High-Tide Zone

• Part of intertidal; mid-intertidal zone
• Covered in high tides
• Barnacles, limpets, spiral wrack, bladder wrack

Mid-Tide Zone

• Part of intertidal; low-intertidal zone
  • Mostly covered
  • High wave action
• Anemone, mussel, hermit crab, saw wrack, bladder wrack, limpets, sea stars, sea palms

Low-Tide Zone

• Subtidal
  • Exposure at lowest tides
• Faunal turf, kelp forest, benthic invertebrates; surf grass, seaweeds, sea urchin, anemone

Subtidal Zone

• No exposure
• Nudibranchs in low tide

Kelp Forests

• Algae
  • Protists
  • Colonial growth
  • Pneumatocysts (Air bladders), Holdfasts, Stipes, Fronds, Blades
  • Similar reproduction to mosses and ferns; alternation of generations
  • Three phyla
    • Phaeophyta (Brown algae) — Shallow, temperate or arctic water
      • Postelsia palmaeformis (Sea palm)
      • Egregia menziesii (Feather boa kelp)
      • Desmarestia ligulate (Flat acid kelp)
        • Sulfuric acid
    • Rhodophyta
      • Corallina sp.
      • Porphyra sp.
    • Chlorophyta — Shallow seas, tidepools
      • Ulva sp.
      • Codium fragile (Dead man’s fingers)
  • Examples in CA
    • Giant kelp; Macrocystis pyrifera
      • Macrocystis genus also present in other coldwater coasts; Chile, South Africa, Tasmania, Australia, New Zealand, islands on Southern hemisphere near Antarctica
    • Bull kelp; Nereocystis luetkeana
• Conditions to produce kelp forests
  • Cold water with high nutrient content (Nitrogen, Phosphorus)
  • Shallow; near shore-water; photic zone reaches sea floor
  • Hard, rocky substrate

Faunal Communities

Cyanobacteria

• Chemical fossils; microfossils; breakdown pigment products
• Precambrian rock
• caused Proterozoic oil deposits, pisolite structures, stromatolites
• oxygen atmosphere generated by cyanobacterial photosynthesis

Phytoplankton

• Protists
• Unicellular eukaryotic cells; microscopic algae
  • Photosynthetic cyanobacteria included in phytoplankton
• Phyto: plant; plankt-; wandering
• Planktonic; propelled by wave currents
• Dinoflagellates, diatoms

Invertebrates

Sea Stars

• Water vascular system
• Pentaradial symmetry
• Pisaster ochraceus (Ochre star)
• Patiria miniata (Bat star)
• Sea Star Wasting Disease/Syndrome
  • Tumorous lesions

Sea Urchins

• Low intertidal zone
  • Created sanctuaries for lowest tides
• Aristotle’s lantern
• Strongylocentrotus franciscanus (Red sea urchin)
  • Uni
• Strongylocentrotus purpuratus (Purple sea urchin)
  • Tidepools

Barnacles

• Upper limit of intertidal
  • High stress factors
• Operculums
• Hermaphroditism, cypris
• Balanus sp. (Acorn Barnacles)
  • Balanus glandula

Sea Anemones

• Nematocysts
• Sessile polyp growth
• Anthopleura elegantisima (Aggregating anemone)
  • Lonngitudinal Fission
  • Preyed by Dermasterias imbricata (leather star)
• Anthopleura xanthogrammica (Giant green anemone)
  • Zooxanthellae
• Epiactis prolifera (Brooding anemone)
  • Hermaphroditic

Mole Crabs

• Emerita analoga
• Sand crabs
• Streamlined for burrowing; backwards and down movement to move with waves
• Filtering particles with long antennae

Sand Dollars

• Dendraster excentricus
• Pedicellariae; pinchers that clear debris on surfaace
• Bleached sand dollars
• Large sand dollar beds; upright filtering on sand

Innkeeper Worm

• Urechis caupo
• U-shape burrows
• Filter feeding with a fine mesh mucous net on edges of burrow
  • Peristaltic pumps of water through burrow to ingest food particles
• Commensalist relationships

Moon Snail

• Euspira lewisii
• Largest species on eastern Pacific coast
  • Large mantle
• Active carnivore
  • Radula and enzyme drill and dissolve prey shells
  • Plow through mud and eel grass
• Sand collar case for eggs

Shore Birds

• Short-billed dowitcher, red phalarope, marbled godwit, whimbrel, greater yellowlegs, semipalmated plower, killdeer, baird’s sandpiper, least sandpiper
• Resource partitioning via variations in beak size/length/shape, leg length, toe type
  • Tactile, sensitive beaks
  • Adapted for wading and stable walking on soft mud or wet sand

Fishes

California Grunion

• Leuresthes tenuis
• Terrestrial spawning behavior
  • Females lay eggs on beach sand
  • Males wrap around female and fertilize eggs
  • Fish return to sea in next wave

Marine Mammals

• Terrestrial ancestors
• Present synapomorphies
  • Streamlining
  • Flukes and flippers
  • Thick fur or blubber (Insulative synapomorphies)
  • Baleen whales vs. toothed whales
• California sea otter, California sea lion, harbor seal, northern elephant seal
• California grey whale

CA Sea Otter

• Enhydra lutris nereis
• Southern sea otter
• Thick, water-resistant fur
  • No blubber
  • Fur grooming
  • Specialized oil secretion
  • Sensitive to soiling
• Webbed hind feet
  • Propulsion
• Tool use (rock use) for abalone/shelling
• Eat 30% body weight to stay warm
• Just over 3,000 individuals
  • Low diversity; 16,000 killed nearly to extinction, Oregon to Baja CA
• Keystone species
  • Kelp beds and sea grass; eat urchins and crabs
• Indicator species
  • Sensitive to contamination
  • Fatal toxoplasmosis; house cat feces
• Umbrella species
  • Protections on sea otters shelter/benefit other species, habitats, ecosystems

CA Sea Lion

• Zalphus californianus
• Arf arf
• Long neck
• Pinnae
• Large front flippers
• Rotatable hind flippers
• Heavy, sexual dimorphism
  • Males: 1000lb, 7-8 ft, dark brown sagittal crest
  • Females: 600lb, 6 ft, light brown s.c.
• ~ 60,000 individuals remaining

Harbor Seal

• Phoca vitulina
• Short neck
• No ear pinnae
• Small front flippers with toes and nails
• 250-300 lbs
• Spotted coat
• Large eyes
• ~200,000 total, only ~2,000 in CA

Northern Elephant Seal

• Mirounga angustirostris
• Sexual dimorphism
  • Males: ~5000lbs, 16ft, bulbous snout
  • Females: ~1700lbs, 11ft
• Brown
• Genetic bottleneck; ~150,000 individuals

CA Gray Whale

• Eschrichtius robustus
• 40 tons, ~50ft
• Filter-feeding; baleen
  • Short baleen plates
• 2 blowholes; V-shape snout
• Gray-white coat
• No dorsal fin; dorsally raised bumps/ridges
• Wide, notched flukes
• Previously critically endangered; ~26,000 individuals
• Longest migration period of any mammal; 10-12 thousand miles annually
  • Feeding grounds: Arctic
  • Mating and calving grounds: Baja CA
  • Gray Whale Observation Posts

Orcas

• Orcinus orca
• Cold coastal waters
• Diverse diets
  • Resident pods: fish
  • Transient: marine mammals
• Communicative, cooperative hunting pods
• Birth rate every 3-10 years; gestation 17 months, nursing up to 2 years
• Issues in captivity