Longevity Can Buffer Plant and Animal Populations Against Changing Climatic Variability

Abstract

Abstract. Both means and year-to-year variances of climate variables such as temperature and precipitation are predicted to change. However, the potential impact of changing climatic variability on the fate of populations has been largely unexamined. We analyzed multiyear demographic data for 36 plant and animal species with a broad range of life histories and types of environment to ask how sensitive their long-term stochastic population growth rates are likely to be to changes in the means and standard deviations of vital rates (survival, reproduction, growth) in response to changing climate. We quantified responsiveness using elasticities of the long-term population growth rate predicted by stochastic projection matrix models. Short-lived species (insects and annual plants and algae) are predicted to be more strongly (and negatively) affected by increasing vital rate variability relative to longer-lived species (perennial plants, birds, ungulates). Taxonomic affiliation has little power to explain sensitivity to increasing variability once longevity has been taken into account. Our results highlight the potential vulnerability of short-lived species to an increasingly variable climate, but also suggest that problems associated with short-lived undesirable species (agricultural pests, disease vectors, invasive weedy plants) may be exacerbated in regions where climate variability decreases.

A demographic approach to study effects of climate change in desert plants

“…Our study contributes two notable exceptions to the accepted view that short-lived species, regardless of habitat, are particularly vulnerable to climate change [26]. We argue that for both species, the potential for demographic buffering is high, in the light of the resulting higher stochastic population growth rates.…”

“…A meta-analysis using size-/stage-based demographic models concluded that species with short lifespans are more vulnerable to increased stochasticity than long-lived species [26]. Lewontin & Cohen [29] derived an approximation for the stochastic population growth rate (a ¼ log(l S )) that points to the negative effect of variation in the long run.…”

Effects of sheep grazing and temporal variability on population dynamics of the clonal herb Geranium sylvaticum in an alpine habitat

“…However, the long lifespan of individual plants, as well as life-history traits such as clonal reproduction, tend to enhance population persistence (Eriksson 1996), and long-lived plants generally show more stable population dynamics than short-lived plants (García et al 2008;Silvertown et al 1993). Thus, negative effects of sub-optimal environmental conditions could be expected to be delayed (Morris et al 2008). Previous studies have found a strong positive effect on biomass of G. sylvaticum after protecting it from grazers in alpine snow beds (Moen and Oksanen 1998), but that the magnitude of the effect depends on habitat productivity (Olofsson 2001).…”

The effects of phenological mismatches on demography

“…For instance, longevity can play a role in how quickly growth rate in a population responds to climate change (Morris et al 2008). In their metaanalysis of demographic data for 36 plant and animal species, Morris et al (2008) found that the population growth rates of long-lived species were buffered from changes in rates of reproduction and survival relative to short-lived species. Thus, long-lived species may be better equipped to persist in an environment in which phenological mismatches become increasingly common.…”