CHAPTER 9 COMMUNITY ECOLOGY WHAT THE STORK SAYS A bird species in the Everglades reveals the intricacies of a threatened ecosystem

9 WHAT THE STORK SAYS A bird species in the Everglades reveals the intricacies of a threatened ecosystem At the end of this chapter you will know: Understanding the interconnectedness between the pieces of an ecological community may allow us to better protect and help restore damaged ecosystems.. Learning Outcomes

9 WHAT THE STORK SAYS A bird species in the Everglades reveals the intricacies of a threatened ecosystem At the end of this unit you will know: Knowledge of ecological succession can help ecosystem restoration. Species interactions contribute to the overall viability of an ecosystem. Both biotic and abiotic features of a system can be negatively impacted by human activity Main Concept Wood storks in Florida

9 WHAT THE STORK SAYS A bird species in the Everglades reveals the intricacies of a threatened ecosystem Case study: Nesting pairs of wood storks in the Florida Everglades experienced a rapid and serious decrease in population. In their efforts to restore the wood stork population to viable levels, scientists found that the entire ecosystem was at risk.

9 The well-being of a species depends on the health of its ecosystem How does a system function the way it does? What are the characteristics that allow some species to thrive, and how do the organisms interact with each other and with the environment? These are questions asked within the field of community ecology. Community ecology also includes understanding how species contribute to ecosystems services like pollination, water purification, and trapping contaminants. TERMS TO KNOW: Community ecology Indicator species Ecosystems

9 The well-being of a species depends on the health of its ecosystem Humans have interrupted the balance of the community and changed the way the Everglades functions. The wood stork case study has shown how minor changes in an environment can have major changes in the overall health of the ecosystem. Ecosystem services Carbon processing Climate control Contaminant capture Economic resources through raw materials Energy conversion Flood control Food production Nutrient storage Photosynthesis Pollination Seed banking Soil fertility Storm protection Waste elimination Water purification Water storage Wind buffer

9 Human alterations have changed the face of the Everglades Former uninterrupted web of natural ecosystems—marshes, prairies, swamps, and forests. Human alterations to the Everglades have included resorts, sugar plantations, and urban centers. South Florida today Wood storks in the 1930s numbered 15,000−20,000 nesting pairs throughout South Florida; now there are fewer than 4500 pairs. Draining and development of the Everglades was the norm throughout the middle of the nineteenth and into the twentieth century.

9 Matter and energy move through a community via the food web TERMS TO KNOW: Food chain Food webs Producer Consumer Trophic levels Loss of a single species can disrupt species health, movement of nutrients, and energy flow through the ecosystem.

9 Matter and energy move through a community via the food web TERMS TO KNOW: Food chain Food webs Producer Consumer Trophic levels Loss of a single species can disrupt species health, movement of nutrients, and energy flow through the ecosystem.

9 Matter and energy move through a community via the food web TERMS TO KNOW: Food chain Food webs Producer Consumer Trophic levels 9 Loss of a single species can disrupt species health, movement of nutrients, and energy flow through the ecosystem. Seemingly small losses lead to large impact.

9 Matter and energy move through a community via the food web TERMS TO KNOW: Food chain Food webs Producer Consumer Trophic levels 9 Loss of a single species can disrupt species health, movement of nutrients, and energy flow through the ecosystem. Seemingly small losses lead to large impact.

9 Matter and energy move through a community via the food web TERMS TO KNOW: Food chain Food webs Producer Consumer Trophic levels 9 Loss of a single species can disrupt species health, movement of nutrients, and energy flow through the ecosystem. Seemingly small losses lead to large impact.

9 Matter and energy move through a community via the food web TERMS TO KNOW: Food chain Food webs Producer Consumer Trophic levels Energy is the basis of the food web with photosynthetic organisms capturing light energy from the sun and storing it as sugars. Primary consumers—herbivores—eat these plants for energy. Most energy is released as heat, but the remainder supports metabolism and can become biomass of the consumer at the next level.

8 Matter and energy move through a community via the food web TERMS TO KNOW: Food chain Food webs Producer Consumer Trophic levels Energy is the basis of the food web with photosynthetic organisms capturing light energy from the sun and storing it as sugars. Primary consumers—herbivores—eat these plants for energy. Most energy is released as heat, but the remainder supports metabolism and can become biomass of the consumer at the next level.

9 Matter and energy move through a community via the food web Consumers are organized into trophic levels based on what they eat. Some organisms feed at more than one trophic level.

9 Matter and energy move through a community via the food web Producers set the budget for the food in a system through their ability to convert light energy into chemical energy. Nutrients cycle and energy flows

9 Matter and energy move through a community via the food web Primary consumers eat primary producers. Most of the energy is released as heat—the rest is used to support metabolism and a small amount becomes biomass. Nutrients cycle and energy flows

9 Matter and energy move through a community via the food web Secondary consumers eat primary consumers. Nutrients cycle and energy flows

9 Matter and energy move through a community via the food web Quaternary consumers eat tertiary consumers. Because such a small percentage of energy becomes biomass at each successive level, most terrestrial food webs don’t go higher than TL5. Nutrients cycle and energy flows

9 Matter and energy move through a community via the food web Wood storks are near the top of a food chain that begins with sawgrass, cypress and mangrove trees, and phytoplankton. Nutrients cycle and energy flows

9 The Everglades are shaped by biotic and abiotic factors TERMS TO KNOW: Detritivores Decomposers Gross primary productivity Net primary productivity (NPP) Biotic (living) and abiotic (non-living) components of an ecosystem are key to the ecosystem’s entire function. In the Everglades, flooding from the rainy season allows fish to reproduce and grow over thousands of acres. As dry-down begins and the waters recede, foraging storks follow the concentration of fish. Connectedness between landscape and life is common in the Everglades.

9 The Everglades are shaped by biotic and abiotic factors TERMS TO KNOW: Niche Habitat Resilience Species diversity Species richness Species evenness Ecotones Edge effects Edge species Core species Ecosystem complexity increases as more interactions exist and become part of stable functioning. With more complexity come more niches and greater survival potential for many species. Along with more possible niches, a complex community is generally more resilient to change. Diversity is qualified by richness—the variety of species—and by evenness—relative abundance of each species.

9 The Everglades are shaped by biotic and abiotic factors To measure richness and diversity, the state is divided into blocks. For each block, the number of species present and the representation (abundance) of each species is compared. With greater evenness, survival of each species and of the community is more stable. In the example, each block has 423 species, but the relative abundance of each species is closer in the east coast example than in the west coast. Species of low abundance - more likely to die out.

9 The Everglades are shaped by biotic and abiotic factors To measure richness and diversity, the state is divided into blocks. For each block, the number of species present and the representation (abundance) of each species is compared. With greater evenness, survival of each species and of the community is more stable. In the example, each block has 423 species, but the relative abundance of each species is closer in the east coast example than in the west coast. East coast – greater diversity due to more even abundance

9 The Everglades are shaped by biotic and abiotic factors Ecotomes occur when two distinctive ecosystems meet. The physical differences between the two areas create edge effects, which either attract or repel some species. Some species use a part of each community. The mangrove trees and seagrass beds provide an example of an ecotome and its use by snapper.

9 The Everglades are shaped by biotic and abiotic factors Ecotomes occur when two distinctive ecosystems meet. The physical differences between the two areas create edge effects, which either attract or repel some species. Some species use a part of each community. The mangrove trees and seagrass beds provide an example of an ecotome and its use by snapper.

9 The Everglades are shaped by biotic and abiotic factors Ecotones occur when two distinctive ecosystems meet. The physical differences between the two areas create edge effects, which either attract or repel some species. Some species use a part of each community. The mangrove trees and seagrass beds provide an example of an ecotone and its use by snapper.

9 Changing community structure changes community composition Mangrove trees were a keystone species that development and other changes to land use eliminated. Change to keystones has a greater impact on the ecosystem than might be predicted.

9 Changing community structure changes community composition Mangrove trees were a keystone species that development and other changes to land use eliminated. Change to keystones has a greater impact on the ecosystem than might be predicted.

9 Species interactions are extremely important for community viability TERMS TO KNOW: Keystone species Competition Intraspecific competition Interspecific competition Adaptations may bind one species to another through competition for resources. Other strategies also keep ecosystems working. The interdependencies include various levels of benefit to one or more members of the community. Successful communities are those where a certain balance has evolved between all the organisms living there. Purposes of interactions include population and controls to maintain carrying capacity. More diversity means more potential relationships.

9 Species interactions are extremely important for community viability TERMS TO KNOW: Keystone species Competition Intraspecific competition Interspecific competition Adaptations may bind one species to another through competition for resources. Other strategies also keep ecosystems working. The interdependencies include various levels of benefit to one or more members of the community. Successful communities are those where a certain balance has evolved between all the organisms living there. Purposes of interactions include population and controls to maintain carrying capacity. More diversity means more potential relationships.

9 Species interactions are extremely important for community viability TERMS TO KNOW: Resource partitioning Symbiosis Mutualism Commensalism Parasitism Restoration ecology

9 Species interactions are extremely important for community viability TERMS TO KNOW: Resource partitioning Symbiosis Mutualism Commensalism Parasitism Restoration ecology

9 Species interactions are extremely important for community viability TERMS TO KNOW: Resource partitioning Symbiosis Mutualism Commensalism Parasitism Restoration ecology

9 Species interactions are extremely important for community viability TERMS TO KNOW: Resource partitioning Symbiosis Mutualism Commensalism Parasitism Restoration ecology

9 Ecologists and engineers help repair ecosystems 1992 – The Water Resources Development Act enlisted the Army Corps of Engineers to investigate damage to the Everglades. Canals and levees had dramatically altered water levels, ecosystems were being starved, affected by hypersalinity, excessive nutrients, and non-native species. 2000 – The Comprehensive Everglades Restoration Plan (CERP) began a 30-year plan for Everglades restoration through 60 construction projects.

9 Ecologists and engineers help repair ecosystems Disruption and drainage with negative ecosystem results CERP goal to restore flow to historic wetland areas 4000 square miles in historic Everglades

9 Community composition changes over time as the physical features of the ecosystem itself change New species move into an area where they hadn’t been before and become established. These pioneer species set off a series of additional changes as the plant community grows and impacts abiotic conditions such as shade and nutrient levels. As one ecological community replaces another, the changes are largely predictable. Change continues over time as plants and animals progressively replace their predecessors.

9 Community composition changes over time as the physical features of the ecosystem itself change New species move into an area where they hadn’t been before and become established. These pioneer species set off a series of additional changes as the plant community grows and impacts abiotic conditions such as shade and nutrient levels. As one ecological community replaces another, the changes are largely predictable. Change continues over time as plants and animals progressively replace their predecessors.

9 Community composition changes over time as the physical features of the ecosystem itself change TERMS TO KNOW: Ecological succession Primary succession Pioneer species Secondary succession Climax species Climax community

9 Community composition changes over time as the physical features of the ecosystem itself change

9 Community composition changes over time as the physical features of the ecosystem itself change

9 Community composition changes over time as the physical features of the ecosystem itself change

9 Community composition changes over time as the physical features of the ecosystem itself change

9 Community composition changes over time as the physical features of the ecosystem itself change

9 Community composition changes over time as the physical features of the ecosystem itself change

9 U.S. Fish and Wildlife Service: http://fws.gov/news/blog PERSONAL CHOICES THAT HELP U.S. Fish and Wildlife Service: http://fws.gov/news/blog

UNDERSTANDING THE ISSUE 9

UNDERSTANDING THE ISSUE 9

9 ANALYZING THE SCIENCE

EVALUATING NEW INFORMATION 9

MAKING CONNECTIONS 9