intertidal zone

low tidal range: 2ft due to Wind effect

Between highest tide level and lowest

Distance between highest and lowest tide levels

long, narrow bays have most extreme tidal range ex East Canada- Bay of Fundy-25ft tidal range

list high and low tides etc

• Field trip-low tide
• Boat/scuba-high tide

Zero mark

Its set by observation-they keep record of highest and lowest tide for year; avg measurement=> ?

Area with tidal effects

Area below intertidal to deepest wave effects

• earth rotates around sun, moon rotates around earth; Moon pulls at water on earth on same side of it=>high tide
• Opposite side of earth has low tide

• When tide seems to "spring" up: Higher highs and lower lows
• Occurs was EATH->moon-> sun in that order=>higher tidal range

• Lesser tidal range
• Occurs when sun and mood are perpendicular

Gradually move as earth rotates

• 1 high and 1 low tide per day
• Tropics

• 2 highs and 2 lows per day at 6 hour interval
• Pacific coast of USA
• Higher High(HHT) 6ft
• Lower low (LLT) -2ft
• Lower high(LHT) 4ft
• Higher low(HLT) 2ft

• Waves of tidal flow tends to raise water level on 1 side of basin
• Occurs in semi enclosed areas
• Ex Gulf of Mexico

• Respiration-low water levels or water retreats
• Desiccation: drying out
• Exposure to wind and rain
• Exposure to land-based predators: birds are major danger, mammals(coyotes/racoons)
• Trampling &crushing and sand compaction
• When little rain=> higher salt=> when dry out -salt formation= BAD
• Especially at extreme high tide

• Surf-wave banging on tiny organisms can crush or rip away from perch
• Cope by hide, rubbery body, flexible; hang on tight
• Sand abrasion-act like sand paper
• Exposure to Sea water predators-fishes, morays, crabs, octuopus, starfishes
• Ex baracuda into shallow water in search of food

• Leave-fish will swim offshore or go into deeper pools
• Dig in-burrow into sediment
• Cause problems b/c less oxygen
• Store water
• Stay in a shady place
• Body color: light ,pale or camouflaged
• Helps against predators and heat
• Seasonal cycles
• Some species are strictly intertidal
• Ghost crab: ocypode-only live in intertidal b/c they can't compete

• Can be refuges
• Rock jetties with overhang
• May form microhabitats
• At low tide may go under and will see things only seen when diving normally
• Can also have BAD microhabitats-hypersaline, or dead, rotted seaweed or human caused

• Moisture and salt-causes problems with rooted plant
• Salt gets on leaves=>desiccation of leaves
• Some things can handle that