Manipulate the BBS route shapefiles

This function is meant to intake two shapefiles, one per cws and usgs munges them such that they conform to the USGS data release for BBS observations and route metadata.

make_bbs_spatial(
  df,
  grid,
  cws.routes.dir,
  usgs.routes.dir,
  cws.layer = "ALL_ROUTES",
  usgs.layer = "US_BBS_Route-Paths-Snapshot_Taken-Feb-2020",
  crs.target = 4326,
  ncores = parallel::detectCores() - 1,
  keep.empty.cells = TRUE,
  overwrite = FALSE,
  dir.out = NULL,
  save.route.lines = TRUE
)

Arguments

df

A data frame with columns c(latitude, longitude) and optional attributes (columns).

grid

a spatial grid over which the eBird data will be overlaid.

cws.routes.dir

Directory for where the CWS (Canadian BBS) shapefiles are stored.

usgs.routes.dir

Directory for where the USGS (USA BBS) shapefiles are stored.

cws.layer

Name of the layer to import. Defaults to "ALL_ROUTES"

usgs.layer

Name of the layer to import.

crs.target

the integer representing the target CRS.

ncores

max number of cores to engage for parallel data processing. Defaults to one fewer CPUs than the machine has. Parallel processing is used only when a high number of routes and/or grid cells are in the data.

keep.empty.cells

logical if FALSE will remove any grid cells with which BBS data do not align. Do not recommend doing this.

overwrite

logical if TRUE will overwrite any existing file named "ebird_spatial.rds" in path dir.out

dir.out

path to where the resulting spatial data frame will be saved. If NULL will not save to file.

save.route.lines

logical. If TRUE (default) will save the BBS routes segments as .RDS to dir.out