[R] using stepAIC with negative binomial regression - error message

Ben, I tried playing with the "na.action" but that didn't seem to help.  I didn't know of the na.omit function.  It made it much easier to get rid of all the missing values in the file, and now the regression model is running. I hadn't put interactions in the model yet since it wasn't even runn

[R] using stepAIC with negative binomial regression - error message help

Dear List, I am having problems running stepAIC with a negative binomial regression model.  I am working with data on manta ray abundance, using 20 predictor variables.  Predictors include variables for location (site), time (year, cos and sin of calendar day, length of day, percent lunar illumi