Endangered Species Tools A B ecosystem community of living things interacting with each other and with the phys. environment ecosystem examples rainforest, desert, pond, garden, ocen habitat physical place within an ecosystem where a plant or animal can find the specific things it needs to survive keystone species important to entire ecosystem's survival population group of animals that live in a certain area pups 0-6 months juveniles 6-12 months sub adults 1 year to 3 years adults 3 years and above species all plants and animals that share specific characteristics food web made up of food chains, all things that are inter-related kelp habitat requirements calm, salty water with mild temperature population model shows what happens to a population over time niche the part of an ecological system occupied by a endangered species may soon become extinct sea otter adaptation webbed back feet, thick fur, ability to use tools to eat death of juveniles caused by starvation migration and birth ways members can be added to population birth rate relationship between the number of births and the whole population sub-adults sea otter group that caused population to decline ways that pollution affects sea otters weaken immune system, oil on fur, reproductive failure from pcb death of pups caused by starvation death of sub-adults caused by drowning death of adults caused by shark attack overall cause of ocean edge population decline drowning in fish nets effect of prey species without predators population over-growth, less food, another species dies off adaptation physical or behaviour trait that helps a species survive in its natural habitat