Survival and Diversity Life in the Tidal Zone Survival and Diversity

High levels of primary (food) production: driven by phytoplankton Tidal Habitats Great places to live: High levels of primary (food) production: driven by phytoplankton Nutrient rich waters created from river drainage into the sea, and upwelling: the replacement of deep, cold water for surface water driven away by winds.

Tidal Zone Adaptation Tidal habitats change daily with the tides, so organisms adapt, or adjust to changing environmental conditions with special features to: Avoid drying out Anchor themselves to resist waves Limpets shape their shells to fit a specific rock: effective seal against water loss Tube feet of sea star used for locomotion and suction/anchorage Protect themselves from predators Hermit crab hiding in it’s scavenged shell Pipefish well camouflaged in eelgrass bed

Types of Tidal Habitats Different tidal habitats require different adaptations Sandy Beaches and Mud Flats Rocky Shores Little protection from strong waves: animals must anchor Complex tide pools possible Seaweeds offer protection from drying Substrate offers lots of nutrients, but little structure for attachment Animals bury themselves in mud Can also attach to plants

Tidal Zones Intertidal Zone Tidal habitats are divided into zones based on relative beach location and how often they are covered by water Splash Zone Intertidal Zone High, Mid and Low High Tide Zone Zones affected daily by changing tides Most adaptation required Middle Tide Zone Low Tide Zone Subtidal Zone

Splash Zone High on beach Out of water most of the time Species must tolerate salt, heat, cold, and extended dry periods Low diversity

Splash Zone Life Lichen Blue-Green Algae Isopods Amphipods Periwinkles

High Tide Zone Increased wave action Species must survive exposure to drying Tide pools provide some protection Higher diversity: includes some animals from splash zone and middle zone (in tide pools)

High Tide Zone Life Barnacles Limpets Shore Crab Rockweed

Middle Tide Zone Most active region Covered and uncovered twice a day Life must tolerate BOTH submersion and exposure to air Animals move in and out of adjacent zones to feed

Purple and Ochre Sea Stars Middle Tide Zone Life Wrinkled Whelks Purple and Ochre Sea Stars Aggregate Anemones Green Algae Blue Mussels

Low Tide Zone Most diverse zone: more plants and animals in low tide zone than in all other zones combined Most food and shelter Less exposure to air and heat Animals unable to exist in other zones

Opalescent Nudibranch Orange Sea Cucumber Low Tide Zone Life Eelgrass Black Katy Chiton Purple Sea Urchin Opalescent Nudibranch Brittle Star Calcareous Tube Worm Giant Green Anemone

Subtidal Zone Just below Intertidal Zone Almost never exposed Many consumer animals: prey on animals in low tide zone Life forms less tolerant to changes: do not have adaptations to allow them to survive without water

Subtidal Zone Life Wolf Eels Pipefish Jellyfish Octopus Salmon

Each zone requires unique adaptations for survival Summary Exposure to Water Diversity Splash Zone High Tide Zone Middle Tide Zone Low Tide Zone Subtidal Zone Most Diverse Most time Each zone requires unique adaptations for survival