The main aims of the conservation are 1) to avoid extinction of local populations and even entire species, and 2) to support the recovery of populations and species that have declined owing to, for example, environmental changes, habitat destruction or harvesting. Typically only limited amount of information is available, often because more close population monitoring is only started at the time the population has already declined dramatically. Nonetheless, conservation decisions and actions are required promptly, so decisions often need to be based on limited amount of data available. On the other hand, detecting populations and species at an elevated risk is a precautionary way to avoid declines and extinctions of natural populations. To these ends, some ‘rules of thumb’ are needed for estimating extinction risk and recovery ability.
The study by Hutchings et al. (in press) responds to this need by indentifying life-history correlates of maximum per capita population growth rate (rmax) across taxa. This rate is directly related to recovery ability of a population and inversely related to its extinction risk. The findings of the study show that age at maturity is the primary correlate of rmax, so that higher age at maturity is linked to lower rmax. Interestingly, the study also showed that rmax does not differ between fishes and terrestrial mammals, even though the high fecundity of fishes is often suggested to imply that their recovery ability is be better.
Hutchings JA, Myers RA, Garcia VB, Lucifora LO, Kuparinen A. Life-history correlates of extinction risk and recovery potential. Ecological Applications (in press)