Chapter 38 conservation biology

What are ecosystem services?

benefits provided to humans by natural ecosystems

Include: filtering water and air, decomposition and nutrient recycling, maintaining soil fertility, mitigation of floods landslides and hurricanes

What is conservation biology?

the study and protection of biological diversity

What is the single greatest threat to biodiversity?

human alteration of habitats causing habitat loss

What are endemic species?

those that are only found in a single geographic area, at the greatest risk to their habitat becoming altered with

What is over harvesting?

harvesting at rates that exceed a populations ability to rebound

Harvesting can be maximized at what population level in relation to carrying capacity?

½ K

What is extinction?

disappearance of all populations of a species

what is extirpation?

disappearance of one population of a species

Why is habitat loss the #1 threat to biodiversity?

estimated that ~50% of the earth’s surface has been altered by humans

example: deforestation

forests are often cleared to make way for homes, farms, or to harvest wood

this lowers CO2 absorption, reduces available habitat, and fragments habitat patches (reducing connectivity)

Why is population connectivity critical for biodiversity?

genetic diversity within population decreases if isolated

connections between diverse habitats needed to fulfill life cycle (migrators)

movement corridors are a management tool

How is rapid warming changing the global climate?

global temperatures are increasing as a result of rising concentrations of greenhouse gases produced by human activities

greenhouse gases include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O)

What are climate change effects on species distrubution?

Range shifts: change species composition in communities

some species experience range expansion

other ranges diminish, and some nowhere to go (ex. species near poles, or high altitude)

How does climate change affect the timing of events?

timing mismatches, conditions are right for all migrations, food availability window does not line up

(different environmental factors don’t allow the birds to have peak abundance in resources to fulfill the birds needs)

A species with which life history strategy could more rapidly adapt to match timing changes?

r-selected

How are protected areas preserving biodiversity hotspots?

marine protected area (mpa): restrict human activities to protect habitat and individuals within them

within mpa’s/terrestrial reserves: more diverse communities, more fit individuals

there is often a “spillover effect” of high abundance in proximity to mpa’s

ecotourism benefits (jobs, $)

What is an umbrella species?

a species with large area requirements for which protection of the species offers protection to other species that share the same habitat

What is long-term monitoring?

(pre) informs what historical community structure was; (post) informs the status of the recovery