BUILDING ECOSYSTEMS – BIOTIC FACTORS AFFECTING SURVIVAL Other organisms can affect an individual’s chance of survival in many ways Effects of same species: 1. Cooperation – protect against predators, protect against elements, hunting, social organization 2. Competition – for limited resources, nesting sites, territory, mates - when resources are limited best competitors will survive and reproduce

BUILDING ECOSYSTEMS – BIOTIC FACTORS AFFECTING SURVIVAL Effects of different species: When competition is fierce, communities form symbiotic relationships to improve survival odds and build healthy ecosystems. Symbiosis – living together in close association of organisms from different species - exhibited by more than half of all marine animals

Parasitism (+ - ) one benefits the other is harmed ex: worms, bacteria 2. Mutualism (++) both organisms benefit ex. Wrasses set up “cleaning stations” where they are allowed to eat the parasites off larger reef fish. They get an easy meal and help reduce parasites on fish. ex. Coral is an animal that allows zooxanthellae (algae) to live inside the protection of its hard skeleton. The algae makes food for the sessile animal. NOAA

3. Commensalism (+ o) one benefits, the other not affected ex. The remora fish is allowed to attach itself to the chin of the shark, who is a very messy eater. The remora has someone to catch food for it. The shark is not affected. 4. Collaboration (++) different species benefiting each other, not necessarily continuous or even always between the same individuals ex. Birds and dolphins hunting bait fish together

5. Competition (+ -) between organisms for the same resources ex. different types of seaweed compete for space in a tidal pool 6. Consumer/Predator (+-) eat other organisms for food ex. sharks hunting seals

BUILDING ECOSYSTEMS – ABIOTIC FACTORS AFFECTING SURVIVAL An organism’s habitat is the place where it lives The environment is the set of conditions that exist within the habitat Non–living environmental factors: 7. Depth 1. Sunlight – latitude, depth 8. Oxygen availability 2. Temperature range- depth, lat 9. Stability – waves, wind, currents, tides 3. Substrate – rocky, sandy, silty 4. Salinity 10. Exposure – attachment to rocks 5. Pressure 11. Nutrients 6. Water availability 12. Geographical Terrain – shelter