[R] flagging glm models with warnings

I'm attempting to run 250 permutations of a negative binomial GLM model for data on fish counts. Many of the models are fit appropriately, but some issue warnings such as "convergence not reached" or "step size truncated due to divergence." I've attempted using glm.nb from the MASS package and the

[R] Defining the "random" term in function "negbin" of AOD package

I have tried glm.nb in the MASS package, but many models (I have 250 models with different combinations of predictors for fish counts data) either fail to converge or even diverge. I'm attempting to use the negbin function in the AOD package, but am unsure what to use for the "random" term, whi