Population decline assessment, historical baselines, and conservation
Timothy C. Bonebrake, Jon Christensen, Carol L. Boggs, Paul R. Ehrlich
Here us a good paper that discuses aspects of population decline assessment, historical baselines, and conservation
Scientific and historical knowledge of worldwide animal-population declines is not well documented. The data is very sparse. This knowledge however is absolute perquisite for the best efforts to preserve species.
In this paper the researchers reviewed the literature of long-term studies of population declines across a set of animal taxa and found that only 15% of the studies used data older than 100 years, and 58% of the studies lacked continuous data. The authors describe five general approaches to studying population declines: counting, correlative, evolutionary, geochemical, and historical. The most common method of population assessment was a census/counting approach (75% of studies). This was followed by a range mapping/correlative approach (17% of studies).
Evolutionary, geochemical, and historical approaches are used less often. The authors assert that in combination with traditional counting and correlative methods, they hold great potential as tools for conservation.
The authors signoff saying “The multidisciplinary approaches we identify and advocate here will be useful for understanding and potentially reversing population declines and ultimately stemming the tide of extinctions currently underway.”