- No file added yet -
Understanding contributions of cohort effects to growth rates of fluctuating populations
journal contribution
posted on 2020-09-18, 00:47 authored by Heiko WittmerHeiko Wittmer, R Powell, C King1. Understanding contributions of cohort effects to variation in population growth of fluctuating populations is of great interest in evolutionary biology and may be critical in contributing towards wildlife and conservation management. Cohort-specific contributions to population growth can be evaluated using age-specific matrix models and associated elasticity analyses. 2. We developed age-specific matrix models for naturally fluctuating populations of stoats Mustela erminea in New Zealand beech forests. Dynamics and productivity of stoat populations in this environment are related to the 3-5 year masting cycle of beech trees and consequent effects on the abundance of rodents. 3. The finite rate of increase (λ) of stoat populations in New Zealand beech forests varied substantially, from 1.98 during seedfall years to 0.58 during post-seedfall years. Predicted mean growth rates for stoat populations in continuous 3-, 4- or 5-year cycles are 0.85, 1.00 and 1.13. The variation in population growth was a consequence of high reproductive success of females during seedfall years combined with low survival and fertility of females of the post-seedfall cohort. 4. Variation in population growth was consistently more sensitive to changes in survival rates both when each matrix was evaluated in isolation and when matrices were linked into cycles. Relative contributions to variation in population growth from survival and fertility, especially in 0-1-year-old stoats, also depend on the year of the cycle and the number of transitional years before a new cycle is initiated. 5. Consequently, management strategies aimed at reducing stoat populations that may be best during one phase of the beech seedfall cycle may not be the most efficient during other phases of the cycle. We suggest that management strategies based on elasticities of vital rates need to consider how population growth rates vary so as to meet appropriate economic and conservation targets. © 2007 The Authors.
History
Preferred citation
Wittmer, H., Powell, R. & King, C. (2007). Understanding contributions of cohort effects to growth rates of fluctuating populations. Journal of Animal Ecology, 76(5), 946-956. https://doi.org/10.1111/j.1365-2656.2007.01274.xPublisher DOI
Journal title
Journal of Animal EcologyVolume
76Issue
5Publication date
2007-01-01Pagination
946-956Publisher
WileyPublication status
PublishedContribution type
ArticleISSN
0021-8790eISSN
1365-2656Language
enUsage metrics
Keywords
elasticityenvironmental variationlife-history strategiesmatrix modelsvital ratesContraception/ReproductionAge FactorsAnimalsConservation of Natural ResourcesEnvironmentFemaleFertilityFood SupplyMaleModels, BiologicalMustelidaePeriodicityPopulation DynamicsPopulation GrowthReproductionSpecies SpecificitySurvival RateEcologyEnvironmental SciencesBiological SciencesAgricultural and Veterinary SciencesGeneticsEcology
Licence
Exports
RefWorksRefWorks
BibTeXBibTeX
Ref. managerRef. manager
EndnoteEndnote
DataCiteDataCite
NLMNLM
DCDC