458 Meta-population models and movement Fish 458; Lecture 18.

Slides:



Advertisements
Similar presentations
Population Numbers.
Advertisements

Population Ecology. Population Demographics Demographics are the various characteristics of a population including, Population Size, Age Structure, Density,
WHAT HAPPENS TO THOSE LARVAE ANYWAY?
Population Dynamics Focus on births (B) & deaths (D)
10 Population Dynamics. 10 Population Dynamics Case Study: A Sea in Trouble Patterns of Population Growth Delayed Density Dependence Population Extinction.
458 Generation-Generation Models (Stock-Recruitment Models) Fish 458, Lecture 20.
Habitat Reserves 1.What are they? 2.Why do we need them? 3.How do we design them?
458 Meta-population models and movement (Continued) Fish 458; Lecture 19.
Populations: Variation in time and space Ruesink Lecture 6 Biology 356.
Announcements Added a README file re: VORTEX HW3 due Wednesday First draft due April 16 (Changed from April 13)!
458 Lumped population dynamics models Fish 458; Lecture 2.
Life Table Problem In a population of field mice, 50% of an original cohort of females survive long enough to breed as one year olds. At that time they.
Population Dynamics in a Stirred, not Mixed, Ocean Bruce Kendall, David Siegel, Christopher Costello, Stephen Gaines, Ray Hilborn, Robert Warner, Kraig.
458 Age-structured models Fish 458, Lecture Why age-structured models? Advantages: Populations have age-structure! More realistic - many basic.
Salit Kark The Biodiversity Research Group Department of Evolution, Systematics and Ecology The Silberman Institute of Life Sciences The Hebrew University.
POPULATION ECOLOGY.
Population Viability Analysis. Conservation Planning U.S. Endangered Species Act mandates two processes –Habitat Conservation Plans –Recovery Plans Quantitative.
Population Ecology Population: A group of organisms that belong to the same species that live in the same place at the same time.
Announcements September 8, Population Biology Lecture Objectives: 1.Learn the population characteristics that determine population growth rate 2.Understand.
CHAPTER 1 / SECTION 2 STUDYING POPULATIONS.
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings PowerPoint Lectures for Biology, Seventh Edition Neil Campbell and Jane Reece.
Population Growth and Regulation
Chapter 4 Populations. Properties of Populations Population: a group of organisms of 1 species in the same area 1) Population Size (usually estimated)
Understanding Populations The Human Population From 1900 to 2003, the population tripled in size to reach 6.3 billion people Today, the human population.
Population Growth Chapter 14, sections 3, 4, and 5.
Population Biology: Demographic Models Wed. Mar. 2.
Chapter 42: Scope of Ecology Ecology: the study of interactions of organisms with other organisms and with the physical environment (word means "study.
Populations Ecology Unit Newark Academy Summer Session 2014.
Ecology: Lectures 4 & 5 Properties of Populations.
Population A population consists of all the members of a particular species that live within an ecosystem and can potentially interbreed.
Competition ESE I. Population size A. Population density- # of individuals that live in a given area B. Growth Rate 1. exponential growth curve.
Measuring and Modeling Population Change SBI4U. Demography The statistical study of the processes that change the size and density of a population through.
Lecture – Populations Properties Estimation of Size Population Growth.
Spatial ecology I: metapopulations Bio 415/615. Questions 1. How can spatially isolated populations be ‘connected’? 2. What question does the Levins metapopulation.
Chapter 3: Ecological and Evolutionary Principles of Populations and communities.
Population Ecology- Continued
Ecology An Introduction and Population Growth. Ecology Ecology – is the science that deals with the interrelationships among living things and their environment.
Populations Ch.19. (19-1) Understanding Populations Population: group of 1 species living in the same place at 1 time 3 characteristics: –Size –Density.
Population Dynamics Focus on births (B) & deaths (D) B = bN t, where b = per capita rate (births per individual per time) D = dN t  N = bN t – dN t =
Chapter Fitty-Two Population Ecology Chuck and Metzler and Baldwin’s Little Sister.
Sources of Fish Decline Habitat disruption Breeding areas Larval development areas Bottom structure.
Chapter 5 How Populations Grow. Characteristics of Populations  Population density  The number of individuals per unit area.  Varies depending on the.
POPULATION. What is a population? All the members of the same species that live in the same area. 3 Characteristics of any population: 1. Population Density.
Population Numbers AG-WL-6. Population Dynamics  Short and long term changes in the size and age composition of populations, and the biological and environmental.
Population density - number of individuals that live in a defined area.
Population Ecology. What is a Population? Population - A group of individuals of the same species that live together and interbreed Populations: o Share.
4.3 Population Growth.
Populations Characteristics and Issues. Population Characteristics A population is a group of individuals of the same species inhabiting the same area.
Populations. Remember a population is… A group of the same species in the same area at the same time. A group of the same species in the same area at.
Understanding Colonial Wading Bird Metapopulation Dynamics in the NJ Meadowlands and NY Harbor Mentor: Prof. Gareth J. Russell UBM Student: Abraham Rosales.
Chapter 6: Population and Community Ecology. Key Ideas There are clear patterns in the distribution and abundance of species across the globe. Understanding.
Populations Chapter 19. Understanding Populations Section 19.1.
The form of the growth curve sketched by a population increasing from low numbers is determined by the relationship between the population and the dynamics.
Populations are described by density, spatial distribution, and growth rate. Population Ecology.
Closures. 2 Seasons –Can fish only at certain times. Areas –Fishing restricted in specific locations. Fisheries –Fishing is completely prohibited.
10-5 POPULATION PATTERNS. 1. POPULATION PROPERTIES Size (often hard to measure) Density– amount of population per unit of area (population crowding) #
Delay-difference models. Readings Ecological Detective, p. 244–246 Hilborn and Walters Chapter 9.
Spatial models (meta-population models). Readings Hilborn R et al. (2004) When can marine reserves improve fisheries management? Ocean and Coastal Management.
Populations Chapter 19. Understanding Populations Section 19.1.
Chapter 4 Population Biology
FW364 Ecological Problem Solving Class 18: Spatial Structure
Population and Community Ecology
Characteristics of a Population
History and meaning of the word “Ecology”
The concept of population and unit stock
Lecture 12 Populations.
Chapter 53 – Population Ecology
Chapter 5.1 How Populations Grow.
Ecosystem Connectivity
Another Paradigm Shift (Hanski and Simberloff 1997)
Presentation transcript:

458 Meta-population models and movement Fish 458; Lecture 18

458 What is a Meta-population? A set of populations of the same species, usually more or less isolated from one another in discrete patches of spatially separate habitat, that may exchange individuals through migration.

458 Examples of Meta-populations Abalone, rock lobster, coral reef fishes – linked by larval dispersal. Seals and sea lions – linked by juvenile and adult migration. Mountain sheep, spotted owl ….. Meta-population structure is less recognized for highly mobile fish species.

458 A General Model The number in population i at the start of time-period t+1 depends on the number in population i at the start of time- period t less the number of emigrants plus the number of immigrants. Note that we may wish to complicate this model with environmental impacts, deaths after migration, etc. As always, one needs to list the assumptions before building the model.

458 Region 1 Region 2 Region 3 Each connection implies more parameters! Harvest

458 Isolation by Distance Model (discrete logistic case) Notes: The boundary is “reflective” – we could have developed a model where animals die if they try to migrate somewhere other than to another patch (an “absorptive” boundary). mmmm

458 An Example of the Discrete Logistic Model The meta-population consists of seven populations (sites) linked through migration. For all sites K=1000 and r=0.4 The movement rate m is constant Only site 7 is harvested Low movement leads to collapse

458 An Example of the Discrete Logistic Model Harvest rate The impact of movement is to prevent extirpation of site 7

458 Specifying a Meta-Population Model (some of the key specifications) Site-specific birth / death / growth processes? Density-dependence – at the site or population level / on what population component? Migration: density-dependent, age-related, distance-related? Environmental variation (correlated among sites – how?) Harvesting, when?

458 Extending the Logistic Model Include harvesting at all sites. Allow different sites to have different K and r. Allow movement among non-adjacent sites. What about density-dependent migration? What about a reserve – can this increase yield?

458 Adding Density-Dependent Migration-I Lets assume that movement only occurs when the population is close to its carrying capacity, i.e.: We could restrict movement to sites that are not close to their carrying capacities (but we won’t this time).

458 Adding Density-Dependent Migration-II Note the change at high exploitation rates Whoops, the discrete approximation seems to lead to oscillations – why?

458 Adding Density-Dependent Migration-III We can attack this problem assuming a continuous model: The Runga-Kutta method was used to do the integration.

458 Adding Density-Dependent Migration-IV These results are qualitatively different from those based on the discrete model!

458 Some Meta-Population Structures (baleen whales) Panmixia Common Breeding ground Complicated!

458 Modeling dispersal-I Dispersal may be a function of: Density on the “source” site. Density on the “target” site. Distance between sites. Homing: Do dispersers join the population to which they disperse? Do they return to their original site?

458 Modeling Dispersal - II Dispersal proportional to density on the “source” site: Dispersal rate increases linearly (or non-linearly) with density on the “source” site:

458 Modeling Dispersal – III (Homing) Lack of homing is a common assumption when dealing with larval movement / settlement of juveniles but may not be appropriate for adults. Example: Northern bluefin tuna Movement between the east and west Atlantic shown through tagging. Age at maturity is 4 in the eastern Atlantic but 8 in the western Atlantic!

458 Protected Areas: Objectives We can use meta-population models to examine the extent to which alternative protected area definitions satisfy the need for: Biodiversity conservation. Protection of spawning aggregations. Reduction of fishing mortality. Habitat protection. (Unfished) controls for scientific study. (Unfished) reserves to “generate” large / old animals for trophy exploitation. Increased yield outside of the reserve.

458 Readings Burgman et al. (1993); Chapter 5. Quinn and Deriso (1999); Chapter 10.