Essay styles. Structured populations. Metapopulations. Classic metapopulation model. Classical metapopulation model

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1 Review paper Essay styles choose a topic, decide on a title after reading some more general papers, focus Make an outline Introduce the subject, explain your rationale, and state your central question, objective, or thesis. Focus discussion on your objectives Document your paper thoroughly Do not use direct quotes, if you can avoid them. End with a general discussion (and the annotated literature) Mainland Structured populations Island Stepping Stone model Metapopulation Opinion paper similar to review, but include opinion based on facts, why this opinion/alternatives Subpopulation Metapopulations Classic metapopulation model Metapopulation Subpopulation A population of local populations which are established by colonists, survive for a while, send out migrants and eventually disappear. Habitat patches are discrete All populations have a substantial (and equal) risk of extinction Equal dispersal among all patches Dispersal fairly rare Ignore population dynamics within a patch Extinction (E) and Colonization (C) Classical metapopulation model E probability that an occupied patch will go extinct. Rate C probability that an unoccupied patch will be recolonized Fraction of patches occupied

2 Classical metapopulation model Rate Colonization Extinction Equilibrium metapopulation size Fraction of patches occupied Classical metapopulation model Metapopulation size is the number of occupied patches! occupied patches are a function of balance of extinction and colonization E>C E=C E<C metapopulation declines metapopulation is stable metapopulation grows Metapopulation example Glanville Fritillary Melitaea cinxia Photograph by Alan Barnes Figure 1 Map of Åland in southwestern Finland showing the locations of the 42 local populations from which adult female butterflies were sampled in summer 1996 (large symbols). All known suitable meadows are shown as small circles, with meadows in which Glanville fritillary larvae were present in autumn 1995 indicated by black circles (and large symbols), and unoccupied meadows by white circles. Of the 42 local populations sampled, the 35 that survived to autumn 1996 (green circles) are distinguished from the seven that went extinct (red triangles). Classic metapopulation model Metapopulation ideas important for conservation Habitat patches are discrete All populations have a substantial (and equal) risk of extinction Equal dispersal among all patches Dispersal fairly rare Classic metapopulation not all that common, but some metapopulation ideas apply to many real systems Migration between patches can help species persistence Some species require multiple patches of habitat Multiple patches can spread the risk of stochastic extinction Empty patches are important

3 Source - sink metapopulations Source - sink metapopulations Habitat patches vary in quality Source has a high quality habitat Sink has a low quality habitat Rescue effect: sink population go extinct without immigration from sources. The source rescues the sink. Dispersal Dispersal λ 1 Source Sink λ < 1 λ 1 Source Sink λ < 1 Source - sink metapopulations Source-sink relationships are defined by growth rate, NOT population size N c = 50 λ 1 Source Dispersal Sink N c = 200 λ < 1 is management of whole ecosystems rather than individual species commodities clean water / flood control aesthetics...

4 Stake have a real or perceived interest in the resource, its use, its protection. are dependent on the resource have a believe that management decisions will directly or indirectly affect them are located in or near the area pay for the decision are in a position of authority to review the decisions

5 Adaptive management Use adaptive management Adaptive management treats management decisions as experiments. Change management if data show not getting desired result. Implement plan management ("Let's put the plan to action") Adaptive management Adaptive management treats management decisions as experiments. Change management if data show not getting desired result. Plan and design ("How can we accomplish our goals?") Assessment and monitoring ("Is the plan working?") Baseline data Experimental data Evaluation and decision making ("What are our goals? Do we need a new plan?") include comparison or/and control replicate! Adaptive management What is the effect grazing on a plant community in an open field?

6 We need a control! We need a control! What is the effect of grazing on the plant community in open fields? Diversity ungrazed

7 What is the effect of grazing on the plant community in open fields? What is the effect of grazing on the plant community in open fields? Diversity What is the point of reference/control? Replication? ungrazed grazed What is the effect of grazing on the plant community in open fields? What is the point of reference/control? Replication. YES for THIS field, but not for treatment (all fields in general)!"pseudoreplication Field 1 Field 4 What is the effect of grazing on the plant community in open fields? Field 2 Field 3 Diversity ungrazed grazed

8 Ecosystem and resilience Resilience is the magnitude of disturbance that can be absorbed or accommodated by an ecosystem before its structure is fundamentally changed to a different state. Example: Shrubland turns into grassland, grassland turns into desert. Adaptive management: Take 2 Adaptive management is a process that combines democratic principles, scientific analysis, education, and institutional learning to manage resources sustainably in an environment of uncertainty. [Lee 1993] Commitment to improve the outcomes of management over biological time scales. Awareness of the experimental nature of management. Willingness to accept the risk of perceived failures. A common understanding, with stake, of the goals, strategies, and uncertainties of management. Holling 1973 A mandate for action from the stake or other authorities Use of natural processes to manage ecosystems Fire regime for different ecosystem types Preservation of an ecosystem was often synonym with keeping the status quo, this resulted very often in damaging the ecosystem. Fire Forest and Woodland Types Understory fires 0 to 10 years Understory fires 0 to 34 years Mixed severity fires 0 to 34 years Mixed severity fires 35 to 200 years Mixed severity fires 201 to 500 years Mixed severity fires 500+ years Stand replacement fires 0 to 34 years Stand replacement fires 35 to 200 years Stand replacement fires 201 to 500 years Stand replacement fires 500+ years Grass and Shrub Types Mixed severity fires 0 to 34 years Stand replacement fires 0 to 10 years Stand replacement fires 0 to 34 years Stand replacement fires 35 to 100 years Stand replacement fires 101 to 500 years Other Water igure 1-2 Fire regime types based on Kuchler s Potential Natural Vegetation types (prepared by Jim Menakis). Prescribed fires Fire suppressed Adaptive management: Learning from errors. Burning of Long-leaved pine forests during growing (back) and non-growing season (front) Hardwood confined to understory Hardwood dominant

9 Use of natural processes to manage ecosystems Preservation of an ecosystem was often synonym with keeping the status quo, this resulted very often in damaging the ecosystem. Fire Water flow Use of natural processes to manage ecosystems Preservation of an ecosystem was often synonym with keeping the status quo, this resulted very often in damaging the ecosystem. Fire Water flow Herbivory Zonation management Exclusion area Managed area Core protection area

10 National Park Service U.S. Forest Service U.S. Fish and Wildlife Service TETON National Wilderness Preservation System Lands administered by the U.S. Bureau of Land Management and by states are not shown. BEAVERHEAD- DEERLODGE NF Yellowstone Kilometers Miles North LEE METCALF Madison Gallatin GALLATIN NF M O N T A N A CUSTER NF ABSAROKA-BEARTOOTH LEE METCALF YELLOWSTONE NP NORTH ABSAROKA RED ROCK LAKES NWR RED ROCK LAKES Yellowstone Lake TARGHEE NF I D A H O WINEGAR HOLE Y E L L O W S T O N E JOHN D. ROCKEFELLER, JR. MEMORIAL PARKWAY GRAND SHOSHONE NF JEDEDIAH TETON SMITH TETON NP WASHAKIE P L A T E A U TARGHEE NF Snake NATIONAL ELK REFUGE GROS VENTRE BRIDGER- TETON NF WIND RIVER INDIAN FITZ- RESERVATION PATRICK GRAYS LAKE NWR Green BRIDGER SHOSHONE NF Ecosystem modelling Spatially explicit (GIS) Incorporate as many details as possible (Geology, Climate,...) Incorporate human interactions/use/development Incorporate species compositions (diversity: species, genetics) (Complex and often not enough data) Use adaptive management