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I am looking for some guidance on producing density and population estimates from a point count dataset for about a dozen grassland bird species while linking relationships to a suite of habitat data. I had intended to use package 'detect', adapting previously used code, but in light of a recent paper by Solymos et al. 2018, it does not seem appropriate for these data, as all species have fewer than the 1000 detection sample size suggested by Solymos. So I have been struggling to determine whether using a function in the package 'unmarked' is appropriate or if I should be looking to program Distance. The purpose of my project is practical grassland bird habitat management and conservation. With unmarked, I am unsure which functions should be utilized and how to get the process going. I have reviewed various literature on the package, but would greatly appreciate any help here. Here is the structure for my data: 37 sites, 521 points, 2 survey visits in one year, 3 distance bands (0-50m, 50-100m, >100m), 5 - 1min time intervals-singing & non-singing detections recorded separately survey covariates: site_name, survey_yr, time since local sunrise, sky, wind, temp, surveyor habitat covariates: 29 variables: 12 different grassland community types (proportion), 10 disturbance types (proportion), cover: herb, shrub, bare (integer), height: herb, bare, shrub (integer) Thank you in advance for any help you can provide! David