Article

Life history predicts risk of species decline in a stochastic world.

Department of Ecology and Evolutionary Biology, Rice University, Houston, TX 77005, USA.
Proceedings of the Royal Society B: Biological Sciences (Impact Factor: 5.29). 03/2012; 279(1738):2691-7. DOI: 10.1098/rspb.2012.0185
Source: PubMed

ABSTRACT Understanding what traits determine the extinction risk of species has been a long-standing challenge. Natural populations increasingly experience reductions in habitat and population size concurrent with increasing novel environmental variation owing to anthropogenic disturbance and climate change. Recent studies show that a species risk of decline towards extinction is often non-random across species with different life histories. We propose that species with life histories in which all stage-specific vital rates are more evenly important to population growth rate may be less likely to decline towards extinction under these pressures. To test our prediction, we modelled declines in population growth rates under simulated stochastic disturbance to the vital rates of 105 species taken from the literature. Populations with more equally important vital rates, determined using elasticity analysis, declined more slowly across a gradient of increasing simulated environmental variation. Furthermore, higher evenness of elasticity was significantly correlated with a reduced chance of listing as Threatened on the International Union for Conservation of Nature Red List. The relative importance of life-history traits of diverse species can help us infer how natural assemblages will be affected by novel anthropogenic and climatic disturbances.

2 Bookmarks
 · 
129 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Assessing species vulnerability to environmental changes is a major challenge for conservation. Combinations of biological attributes have already been successfully used for this purpose, allowing large-scale prediction of inter-specific differences in demographic parameters (e.g. abundance) or endangered status. However, studies investigating whether biological attributes could be used to predict the temporal demographic responses of species in a changing environment are still scarce. In this work, we tackled this issue by taking advantage of a multi-decadal survey of concomitant changes in fish communities and environmental conditions within the Terminos lagoon (Mexico). Based on this rare dataset, we first characterized changes in abiotic parameters that occurred in this ecosystem since the 80s. Then, we adapted a multivariate index accounting for changes in both species abundance and occurrence to assess concomitant demographic changes for the 25 dominant fish species in the lagoon, classifying them into five various types of trajectories (“Increasing”, “Decreasing”, “Constant”, “Hump-shape” and “U-shape”). Finally, we assessed the accuracy in prediction of these temporal responses for all possible combinations of 15 biological attributes including taxonomy, ecological and life-history traits. Our results showed that fish specific demographic changes over the last 30 years could be accurately predicted (72% accuracy) using a combination of five biological attributes (spawning season, order, maximum salinity, width of salinity range, oocyte size) among which three could be related to the increase in average salinity occurred in the lagoon over this period. Appropriate sets of complementary biological attributes could similarly allow prediction of inter-specific differences in demographic changes in other areas, thereby offering an additional pragmatic tool for ecosystem managers to identify vulnerable species at the local scale.
    Ecological Indicators 01/2015; 48:147–156. · 3.23 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Life cycles can limit the abilities of species to track changing climatic conditions. We combined age or stage structure and a moving-habitat model to explore the effects of life history on the persistence of populations in the presence of climate change. We studied four dissimilar plant species in moving patches and found that (1) population growth rates, (2) elasticities with respect to the survival (stasis and shrinkage) components of the projection matrix, and (3) the evenness of the elasticities with respect to the components of the projection matrix all decreased as we increased the translational speeds of the patches. In addition, the value of long-distance dispersal increased with patch speed for three of the four species. Our analyses confirm that rapid growth, high fecundity, and long-distance dispersal can benefit species in moving patches. Thus, species with long generation times and limited dispersal ability are especially vulnerable to habitat movement. Stage-structured moving-habitat models can easily incorporate spatial complexity and can help us predict the effects of shifting climatic conditions.
    The American Naturalist 07/2014; 184(1):25-37. · 4.45 Impact Factor

Full-text (7 Sources)

Download
181 Downloads
Available from
May 31, 2014