Characterizing population vulnerability for 758 species

Abstract

We investigate relationships between life history traits and the character of population dynamics as revealed by time series data. Our classification of time series is according to ‘extinction category,’ where we identify three classes of populations: (i) weakly varying populations with such high growth rates that long‐term persistence is likely (unless some extreme catastrophe occurs); (ii) populations with such low growth rates that average population size must be large to buffer them against extinction in a variable environment; and (iii) highly variable populations that fluctuate so dramatically that dispersal or some other refuge mechanism is likely to be key to their avoidance of extinction. Using 1941 time series representing 758 species from the Global Population Dynamics Database, we find that, depending on the form of density dependence one assumes, between 46 and 90% of species exhibit dynamics that are so variable that even large carrying capacities could not buffer them against extinction on a 100‐year time horizon. The fact that such a large proportion of population dynamics are so locally variable vindicates the growing realization that dispersal, habitat connectedness, and large‐scale processes are key to local persistence. Furthermore, for mammals, simply by knowing body size, age at first reproduction, and average number of offspring we could correctly predict extinction categories for 83% of species (60 of 72).

Avian life‐history determinants of local extinction risk in a hyper‐fragmented neotropical forest landscape

“…Despite recent macroecological progress in our understanding of the relationship between sensitivity to anthropogenic disturbance and life-history traits on a global or continental scale (e.g. Purvis et al, 2000;Fagan et al, 2001;O'Grady et al, 2004), few studies have investigated these relationships at the level of local assemblages within a given landscape. Traits commonly linked to local extinction proneness include geographic range size, population size and variability, body mass and life-history specialization.…”

Environmental stochasticity in dispersal areas can explain the ‘mysterious’ disappearance of breeding populations

“…Owing to the current dramatic loss of biodiversity (Leakey & Lewin 1995;Pimm et al 1995), increasing attention is being devoted to rapid and efficient identification of species and populations at risk, to early warning signals and causes of decline, as well as to accurate models yielding reliable predictions of future species and population trends (Fagan et al 2001;Ferrer et al 2003;O'Grady et al 2004). For this reason, many aspects of species life histories and population dynamics have been increasingly explored.…”

Avifauna da Reserva Biológica Municipal Poço D'Anta, Juiz de Fora, MG

“…Os efeitos desta destruição são muitas vezes irreversíveis, afetando a sobrevivência dos organismos (Fagan et al 2001) e o funcionamento dos ecossistemas (Hooper et al 2005). Embora as aves sejam organismos altamente móveis, o grupo não se encontra livre de tal devastação, já que muitas espécies são especialistas de habitat e incapazes de se dispersar por áreas abertas (Lees & Peres 2008).…”