Using Ripley's L-Function to Examine Spatial Clustering in Duck Nests

• Activity Number: 195
• Type: Contributed
• Date/Time: Monday, August 5, 2013 : 10:30 AM to 12:20 PM
• Sponsor: Section on Statistics and the Environment
• Author(s): Nicholas Michaud*+ and Philip Dixon and William Clark and Daniel Fortin and David Howerter
• Companies: Iowa State University and Iowa State Univ and Iowa State University and Iowa State University and Ducks Unlimited Canada
• Keywords: Ecology ; Spatial ; Clustering

Abstract

Ripley's L-function can be used to test whether spatial processes exhibit clustering. We calculated L-functions to characterize the nesting location of duck nests on 219 160-acre sections spread across the Prairie Habitat Joint Venture sites in Canada. We studied the properties of grouping these L-functions according to the amount of clustering they indicate. These groups are examined along with landscape features to determine if certain environmental variables are associated with a high degree of duck nest clustering. Counter to previous studies regarding duck nesting patterns, variables such as wetland area and length of edge among habitat types were not related to the degree of clustering of nests within a quarter-section. Instead quarter-sections with lower numbers of nests exhibited a high degree of clustering, whereas those with greater numbers of nests exhibited less clustering.