Interim Report IR - 02 - 56 Influence of Coloured Noise on the Extinction Risk in Structured Population Models
نویسنده
چکیده
Interim Reports on work of the International Institute for Applied Systems Analysis receive only limited review. Views or opinions ex pressed herein do not necessarily represent those o f the Institute, its National Member Organizations, or ot her organizations supporting the work. Abstract We use simple models too compare extinctionn riskk among basic life history types when environmental noise is either uncorrelatedd (" white ") or positively a utocorrelatedd (" red "). The metric of extinction is probability of extinctionn inn 500 years; variability of noise is scaledd suchh that its expectedd variance is independent of colour at this time scale.. We compare annual,, semelparous biennial,, iteroparous biennial andd perennial l ife histories.. Givenn ann identical equilibrium populationn size andd basic reproductive number ,, annual life histories confer a muchh higher extinctionn riskk thann semelparous biennial life histories.. Iteroparous biennial andd perennial life histories have evenn l ower extinctionn risks.. Autocorrelatedd noise influences the life histories differe ntly: the extinctionn riskk of the annuals decreases withh reddening noise,, whereas the other life hi stories show ann opposite response.. We show that inn a previously developedd stage-structuredd populationn model for the Florida scrubb jay Aphelocomaa coerulescens ignoring the possibility of red environmental noise might result inn a muchh tooo optimistic assessme nt of populationn viability. Inn conclusion,, simplifications of populationn structure and ig noring red environmental noise inn populationn viability analyses cann result inn se rious biases.. Acknowledgments We thankk Tim Bentonn andd Esa Ranta for very helpful comments onn the manuscript.. We acknowledge funding by the Academy of Finlandd (Project 45928)..
منابع مشابه
Extinction risk, coloured noise and the scaling of variance.
The impact of temporally correlated fluctuating environments (coloured noise) on the extinction risk of populations has become a main focus in theoretical population ecology. In this study we particularly focus on the extinction risk in strongly correlated environments. Here, we found that, in contrast to moderate auto-correlation, the extinction risk was highly dependent on the process of nois...
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