Evaluation Sourcebook (.pdf) - School of Natural Resources and ...

INTRODUCTION OBJECTIVES THREATS ASSETS STRATEGIESAge class distribution (proportion of juveniles, fledglings, saplings vs. adults)Percent of forest that qualifies as old growthX What is the population size likely to be next year?Are populations of rare species growing more or less rapidly than previous years? Birth rates; frequency of reproductive events; litter sizeNumber of new recruits per year (recruitment rate; fledgling success)Death or mortality ratesGrowth rate 7Frequency of immigration and emigrationSex ratioData sources• North American Amphibian Monitoring Program:http://www.pwrc.usgs.gov/naamp/• North American breeding Bird Survey: http://www.pwrc.usgs.gov/bbs/• South Atlantic Migratory Bird Initiative: http://samigbird.fws.gov/• Natural Heritage, Audubon or other organization or university surveys• Harvesting records (USFS, timber companies, State hunting/fishing records)• Roadside sightings, point counts or estimatesExampleBobwhite quails in Georgia have declined by more than 70 percent since the 1960s. In orderto address this decline, Georgia’s Department of Natural Resources implemented theBobwhite Quail Initiative (BQI) – a landowner program that improves quail nesting andbrood rearing habitats (two factors limiting quails) across Georgia's landscape. BQI workswith farmland owners and helps landowners make habitat changes to their farmland so thatit is beneficial to Bobwhite quails. To measure the effect of the habitat changes theycompared quail population numbers on BQI farms to farms that did not make any habitatchanges (control farms). The number of calling quails (covey-call-counts) served as anindirect measure of the number of quails at a site. After two years, BQI found that quailpopulations were increasing on BQI farms and declining on control farms. This informationprovides concrete feedback on the effectiveness of their habitat change program.For more information see:http://georgiawildlife.dnr.state.ga.us/content/displaycontent.asp?txtDocument=1087 A population does not have to be growing to be viable. Many natural populations fluctuate at around zeronet growth. A decline in growth rate indicates the need to look at possible threats to the population.Evaluation Sourcebook 37