Updating the Global Population Dynamics Database

The Global Population Dynamics Database has been updated to include the data from Prof Richard Sibley’s recent paper “On the stability of populations of mammals, birds, fish and insects”

The Global Population Dynamics Database (GPDD) has been updated to include the data from Prof Richard Sibley’s recent paper “On the stability of populations of mammals, birds, fish and insects” (Sibley et al. (2007) Ecology Letters 10 (10) 970-976).

Carrying capacities and return rates of 634 populations from the GPDD were calculated.  They found that most can be expected to remain stable despite year-to-year fluctuations caused by environmental factors.  Mean return rates were generally around one but were higher in insects and declined with body size in mammals.  In general this is good news for conservation, as stable populations are less likely to go extinct.  However, the lower return rates of the large mammals may make them more vulnerable.  Their estimates of return rates were generally well below the threshold for chaos, which makes it unlikely that chaotic dynamics occur in natural populations.

The carrying capacities and return rates have been added to the distribution copy of the database, and are also shown on the web site.

Rob Anderson
IT Support Specialist
Silwood Park