diff --git a/DESCRIPTION b/DESCRIPTION
index 1fad99af..8247f945 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -2,8 +2,8 @@ Package: glatos
 Type: Package
 Title: A package for the Great Lakes Acoustic Telemetry Observation System
 Description: Functions useful to members of the Great Lakes Acoustic Telemetry Observation System https://glatos.glos.us; many more broadly relevant to simulating, processing, analysing, and visualizing acoustic telemetry data.
-Version: 0.8.0.9000
-Date: 2024-01-04
+Version: 0.8.0.9001
+Date: 2024-01-13
 Depends: R (>= 3.5.0)
 Imports:
 		av,
diff --git a/NEWS.md b/NEWS.md
index 1300a864..5393bdbd 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -4,6 +4,10 @@
 
 ### Bug fixes
 
+- Omit data.table from class of object returned by `read_glatos_detections()`  
+  and `read_glatos_receivers()`. 
+    - fixes [issue #200](https://github.com/ocean-tracking-network/glatos/issues/200)
+
 - Fix typo in Description to Suggest 'gifski' (not 'gifsky'). 
     - fixes [issue #185](https://github.com/ocean-tracking-network/glatos/issues/185)
 
diff --git a/R/load-read_glatos_detections.r b/R/load-read_glatos_detections.r
index 7ca5151e..3ec9fbcb 100644
--- a/R/load-read_glatos_detections.r
+++ b/R/load-read_glatos_detections.r
@@ -1,135 +1,137 @@
-#' @title Read data from a GLATOS detection file
-#'
-#' @description Read data from a standard GLATOS detection (csv) file and return
-#'   a data.frame of class `glatos_detections`.
-#'
-#' @param det_file A character string with path and name of detection file in
-#'   standard GLATOS format (*.csv). If only file name is given, then the file
-#'   must be located in the working directory. File must be a standard GLATOS
-#'   file (e.g., *xxxxx_detectionsWithLocs_yyyymmdd_hhmmss.csv*) submitted via
-#'   GLATOSWeb Data Portal <https://glatos.glos.us>.
-#'
-#' @param version An optional character string with the glatos file version
-#'   number. If NULL (default value) then version will be determined by
-#'   evaluating file structure. The only allowed values currently are `NULL`,
-#'   `"1.3"`, and `"1.4"`. Any other values will trigger an error. Users should
-#'   never need to set this argument (`NULL` should work).
-#'
-#' @details Data are loaded using [fread][data.table::fread] and timestamps are
-#' coerced to POSIXct using [fastPOSIXct][fasttime::fastPOSIXct]. All times must
-#' be in UTC timezone per GLATOS standard.
-#'
-#' @details Column `animal_id` is considered a required column by many other
-#'   functions in this package, so it will be created if any records are `NULL`.
-#'   When created, it will be constructed from `transmitter_codespace` and
-#'   `transmitter_id`, separated by '-'.
-#'
-#' @return A data.frame of class `glatos_detections`.
-#'
-#' @author C. Holbrook \email{cholbrook@@usgs.gov}
-#'
-#' @examples
-#' # get path to example detection file
-#' det_file <- system.file("extdata", "walleye_detections.csv",
-#'   package = "glatos"
-#' )
-#'
-#' # note that code above is needed to find the example file
-#' # for real glatos data, use something like below
-#' # det_file <- "c:/path_to_file/HECWL_detectionsWithLocs_20150321_132242.csv"
-#'
-#' det <- read_glatos_detections(det_file)
-#'
-#' @importFrom lubridate parse_date_time
-#'
-#' @export
-read_glatos_detections <- function(det_file, version = NULL) {
-  # Read detection file-------------------------------------------------------
-
-  # see version-specific file specifications
-  # internal data object; i.e., in R/sysdata.r
-
-
-  # Identify detection file version
-  id_det_version <- function(det_file) {
-    det_col_names <- names(data.table::fread(det_file, nrows = 0))
-    if (all(glatos:::glatos_detection_schema$v1.4$name %in% det_col_names)) {
-      return("1.4")
-    } else if (all(glatos:::glatos_detection_schema$v1.3$name %in% det_col_names)) {
-      return("1.3")
-    } else {
-      stop("Detection file version could not be identified.")
-    }
-  }
-
-  if (is.null(version)) {
-    version <- id_det_version(det_file)
-  } else if (!(paste0("v", version) %in%
-    names(glatos:::glatos_detection_schema))) {
-    stop(paste0("Detection file version ", version, " is not supported."))
-  }
-
-  #-Detections v1.3 or v1.4-----------------------------------------------------
-  if (version %in% c("1.3", "1.4")) {
-    vversion <- paste0("v", version)
-
-    col_classes <- glatos:::glatos_detection_schema[[vversion]]$type
-    timestamp_cols <- which(col_classes == "POSIXct")
-    date_cols <- which(col_classes == "Date")
-    col_classes[c(timestamp_cols, date_cols)] <- "character"
-
-    # read data
-    dtc <- data.table::fread(det_file,
-      sep = ",", colClasses = col_classes,
-      na.strings = c("", "NA")
-    )
-
-    # coerce timestamps to POSIXct; note that with fastPOSIXct raw
-    #  timestamp must be in UTC; and tz argument sets the tzone attr only
-    options(lubridate.fasttime = TRUE)
-    for (j in timestamp_cols) {
-      data.table::set(dtc,
-        j = glatos:::glatos_detection_schema[[vversion]]$name[j],
-        value = lubridate::parse_date_time(
-          dtc[[glatos:::glatos_detection_schema[[vversion]]$name[j]]],
-          orders = "ymd HMS",
-          tz = "UTC"
-        )
-      )
-    }
-    # coerce dates to date
-    for (j in date_cols) {
-      data.table::set(dtc,
-        j = glatos:::glatos_detection_schema[[vversion]]$name[j],
-        value = ifelse(dtc[[glatos:::glatos_detection_schema[[vversion]]$name[j]]] == "",
-          NA,
-          dtc[[glatos:::glatos_detection_schema[[vversion]]$name[j]]]
-        )
-      )
-      data.table::set(dtc,
-        j = glatos:::glatos_detection_schema[[vversion]]$name[j],
-        value = as.Date(dtc[[glatos:::glatos_detection_schema[[vversion]]$name[j]]])
-      )
-    }
-  }
-  #-end v1.3 or v1.4------------------------------------------------------------
-
-  # create animal_id if missing
-  anid_na <- is.na(dtc$animal_id)
-  if (any(anid_na)) {
-    dtc$animal_id[anid_na] <- with(
-      dtc,
-      paste0(transmitter_codespace[anid_na], "-", transmitter_id[anid_na])
-    )
-    warning(paste0(
-      "Some or all values of required column 'animal_id' were ",
-      "missing so they were created from 'transmitter_codespace' and ",
-      "'transmitter_id'.)"
-    ))
-  }
-
-  # assign class
-  dtc <- as_glatos_detections(dtc)
-
-  return(dtc)
-}
+#' @title Read data from a GLATOS detection file
+#'
+#' @description Read data from a standard GLATOS detection (csv) file and return
+#'   a data.frame of class `glatos_detections`.
+#'
+#' @param det_file A character string with path and name of detection file in
+#'   standard GLATOS format (*.csv). If only file name is given, then the file
+#'   must be located in the working directory. File must be a standard GLATOS
+#'   file (e.g., *xxxxx_detectionsWithLocs_yyyymmdd_hhmmss.csv*) submitted via
+#'   GLATOSWeb Data Portal <https://glatos.glos.us>.
+#'
+#' @param version An optional character string with the glatos file version
+#'   number. If NULL (default value) then version will be determined by
+#'   evaluating file structure. The only allowed values currently are `NULL`,
+#'   `"1.3"`, and `"1.4"`. Any other values will trigger an error. Users should
+#'   never need to set this argument (`NULL` should work).
+#'
+#' @details Data are loaded using [fread][data.table::fread] and timestamps are
+#' coerced to POSIXct using [fastPOSIXct][fasttime::fastPOSIXct]. All times must
+#' be in UTC timezone per GLATOS standard.
+#'
+#' @details Column `animal_id` is considered a required column by many other
+#'   functions in this package, so it will be created if any records are `NULL`.
+#'   When created, it will be constructed from `transmitter_codespace` and
+#'   `transmitter_id`, separated by '-'.
+#'
+#' @return A data.frame of class `glatos_detections`.
+#'
+#' @author C. Holbrook \email{cholbrook@@usgs.gov}
+#'
+#' @examples
+#' # get path to example detection file
+#' det_file <- system.file("extdata", "walleye_detections.csv",
+#'   package = "glatos"
+#' )
+#'
+#' # note that code above is needed to find the example file
+#' # for real glatos data, use something like below
+#' # det_file <- "c:/path_to_file/HECWL_detectionsWithLocs_20150321_132242.csv"
+#'
+#' det <- read_glatos_detections(det_file)
+#'
+#' @importFrom lubridate parse_date_time
+#'
+#' @export
+read_glatos_detections <- function(det_file, version = NULL) {
+  # Read detection file-------------------------------------------------------
+
+  # see version-specific file specifications
+  # internal data object; i.e., in R/sysdata.r
+
+
+  # Identify detection file version
+  id_det_version <- function(det_file) {
+    det_col_names <- names(data.table::fread(det_file, nrows = 0))
+    if (all(glatos:::glatos_detection_schema$v1.4$name %in% det_col_names)) {
+      return("1.4")
+    } else if (all(glatos:::glatos_detection_schema$v1.3$name %in% det_col_names)) {
+      return("1.3")
+    } else {
+      stop("Detection file version could not be identified.")
+    }
+  }
+
+  if (is.null(version)) {
+    version <- id_det_version(det_file)
+  } else if (!(paste0("v", version) %in%
+    names(glatos:::glatos_detection_schema))) {
+    stop(paste0("Detection file version ", version, " is not supported."))
+  }
+
+  #-Detections v1.3 or v1.4-----------------------------------------------------
+  if (version %in% c("1.3", "1.4")) {
+    vversion <- paste0("v", version)
+
+    col_classes <- glatos:::glatos_detection_schema[[vversion]]$type
+    timestamp_cols <- which(col_classes == "POSIXct")
+    date_cols <- which(col_classes == "Date")
+    col_classes[c(timestamp_cols, date_cols)] <- "character"
+
+    # read data
+    dtc <- data.table::fread(det_file,
+      sep = ",", colClasses = col_classes,
+      na.strings = c("", "NA")
+    )
+
+    # coerce timestamps to POSIXct; note that with fastPOSIXct raw
+    #  timestamp must be in UTC; and tz argument sets the tzone attr only
+    options(lubridate.fasttime = TRUE)
+    for (j in timestamp_cols) {
+      data.table::set(dtc,
+        j = glatos:::glatos_detection_schema[[vversion]]$name[j],
+        value = lubridate::parse_date_time(
+          dtc[[glatos:::glatos_detection_schema[[vversion]]$name[j]]],
+          orders = "ymd HMS",
+          tz = "UTC"
+        )
+      )
+    }
+    # coerce dates to date
+    for (j in date_cols) {
+      data.table::set(dtc,
+        j = glatos:::glatos_detection_schema[[vversion]]$name[j],
+        value = ifelse(dtc[[glatos:::glatos_detection_schema[[vversion]]$name[j]]] == "",
+          NA,
+          dtc[[glatos:::glatos_detection_schema[[vversion]]$name[j]]]
+        )
+      )
+      data.table::set(dtc,
+        j = glatos:::glatos_detection_schema[[vversion]]$name[j],
+        value = as.Date(dtc[[glatos:::glatos_detection_schema[[vversion]]$name[j]]])
+      )
+    }
+  }
+  #-end v1.3 or v1.4------------------------------------------------------------
+
+  # create animal_id if missing
+  anid_na <- is.na(dtc$animal_id)
+  if (any(anid_na)) {
+    dtc$animal_id[anid_na] <- with(
+      dtc,
+      paste0(transmitter_codespace[anid_na], "-", transmitter_id[anid_na])
+    )
+    warning(paste0(
+      "Some or all values of required column 'animal_id' were ",
+      "missing so they were created from 'transmitter_codespace' and ",
+      "'transmitter_id'.)"
+    ))
+  }
+
+  # strip data.table and assign glatos_detections class
+  data.table::setDF(dtc)
+  
+  dtc <- as_glatos_detections(dtc)
+
+  return(dtc)
+}
diff --git a/R/load-read_glatos_receivers.r b/R/load-read_glatos_receivers.r
index 1a184aaa..c373c3a4 100644
--- a/R/load-read_glatos_receivers.r
+++ b/R/load-read_glatos_receivers.r
@@ -1,116 +1,118 @@
-#' Read data from a GLATOS receiver location file
-#'
-#' Read data from a standard GLATOS receiver location (csv) file and return a
-#' data.frame of class `glatos_receivers`.
-#'
-#' @param rec_file A character string with path and name of receiver location
-#'   file in standard GLATOS format (*.csv). If only file name is given, then
-#'   the file must be located in the working directory. File must be a standard
-#'   GLATOS file (e.g., *GLATOS_receiverLocations_yyyymmdd_xxxxxx.csv*) obtained
-#'   from GLATOSWeb Data Portal <http://glatos.glos.us>.
-#'
-#' @param version An optional character string with the GLATOS file version
-#'   number. If NULL (default value) then version will be determined by
-#'   evaluating file structure. The only allowed values currently are `NULL` and
-#'   `"1.0"`. Any other values will trigger an error.
-#'
-#' @details Data are loaded using [fread][data.table::fread] and timestamps are
-#'   coerced to POSIXct using [fastPOSIXct][fasttime::fastPOSIXct]. All
-#'   timestamps must be 'YYYY-MM-DD HH:MM' format and in UTC timezone per GLATOS
-#'   standard.
-#'
-#' @return A data.frame of class `glatos_receivers`.
-#'
-#' @author C. Holbrook (cholbrook@usgs.gov)
-#'
-#' @examples
-#' # get path to example receiver_locations file
-#' rec_file <- system.file("extdata",
-#'   "sample_receivers.csv",
-#'   package = "glatos"
-#' )
-#'
-#' # note that code above is needed to find the example file
-#' # for real glatos data, use something like below
-#' # rec_file <- "c:/path_to_file/GLATOS_receiverLocations_20150321_132242.csv"
-#'
-#' rcv <- read_glatos_receivers(rec_file)
-#'
-#' @importFrom lubridate parse_date_time
-#'
-#' @export
-read_glatos_receivers <- function(rec_file, version = NULL) {
-  # Read source file-------------------------------------------------------
-
-  # see version-specific file specifications
-  # internal data object; i.e., in R/sysdata.r
-
-
-  # Identify file version
-  id_file_version <- function(rec_file) {
-    col_names <- names(data.table::fread(rec_file, nrows = 0))
-    if (all(glatos:::glatos_receivers_schema$v1.1$name %in% col_names)) {
-      return("1.1")
-    } else if (all(glatos:::glatos_receivers_schema$v1.0$name %in% col_names)) {
-      return("1.0")
-    } else {
-      stop("Receiver location file version could not be identified.")
-    }
-  }
-
-  if (is.null(version)) {
-    version <- id_file_version(rec_file)
-  } else if (!(paste0("v", version) %in%
-    names(glatos:::glatos_receivers_schema))) {
-    stop(paste0(
-      "Receiver locations file version ", version,
-      " is not supported."
-    ))
-  }
-
-  #-v1.x----------------------------------------------------------------
-  if (version %in% c("1.0", "1.1")) {
-    ver_txt <- paste0("v", version)
-
-    col_classes <- glatos:::glatos_receivers_schema[[ver_txt]]$type
-    timestamp_cols <- which(col_classes == "POSIXct")
-    date_cols <- which(col_classes == "Date")
-    col_classes[c(timestamp_cols, date_cols)] <- "character"
-
-    # read data
-    rec <- data.table::fread(rec_file, sep = ",", colClasses = col_classes)
-
-    # coerce timestamps to POSIXct; note that with fastPOSIXct raw
-    #  timestamp must be in UTC; and tz argument sets the tzone attr only
-    options(lubridate.fasttime = TRUE)
-    for (j in timestamp_cols) {
-      data.table::set(rec,
-        j = glatos_receivers_schema[[ver_txt]]$name[j],
-        value = lubridate::parse_date_time(
-          rec[[glatos_receivers_schema[[ver_txt]]$name[j]]],
-          orders = "ymd HMS",
-          tz = "UTC"
-        )
-      )
-    }
-    # coerce dates to date
-    for (j in date_cols) {
-      data.table::set(rec,
-        j = glatos_receivers_schema[[ver_txt]]$name[j],
-        value = ifelse(rec[[glatos_receivers_schema[[ver_txt]]$name[j]]] == "",
-          NA, rec[[glatos_receivers_schema[[ver_txt]]$name[j]]]
-        )
-      )
-      data.table::set(rec,
-        j = glatos_receivers_schema[[ver_txt]]$name[j],
-        value = as.Date(rec[[glatos_receivers_schema[[ver_txt]]$name[j]]])
-      )
-    }
-  }
-  #-end v1.x----------------------------------------------------------------
-
-  # assign class
-  rec <- as_glatos_receivers(rec)
-
-  return(rec)
-}
+#' Read data from a GLATOS receiver location file
+#'
+#' Read data from a standard GLATOS receiver location (csv) file and return a
+#' data.frame of class `glatos_receivers`.
+#'
+#' @param rec_file A character string with path and name of receiver location
+#'   file in standard GLATOS format (*.csv). If only file name is given, then
+#'   the file must be located in the working directory. File must be a standard
+#'   GLATOS file (e.g., *GLATOS_receiverLocations_yyyymmdd_xxxxxx.csv*) obtained
+#'   from GLATOSWeb Data Portal <http://glatos.glos.us>.
+#'
+#' @param version An optional character string with the GLATOS file version
+#'   number. If NULL (default value) then version will be determined by
+#'   evaluating file structure. The only allowed values currently are `NULL` and
+#'   `"1.0"`. Any other values will trigger an error.
+#'
+#' @details Data are loaded using [fread][data.table::fread] and timestamps are
+#'   coerced to POSIXct using [fastPOSIXct][fasttime::fastPOSIXct]. All
+#'   timestamps must be 'YYYY-MM-DD HH:MM' format and in UTC timezone per GLATOS
+#'   standard.
+#'
+#' @return A data.frame of class `glatos_receivers`.
+#'
+#' @author C. Holbrook (cholbrook@usgs.gov)
+#'
+#' @examples
+#' # get path to example receiver_locations file
+#' rec_file <- system.file("extdata",
+#'   "sample_receivers.csv",
+#'   package = "glatos"
+#' )
+#'
+#' # note that code above is needed to find the example file
+#' # for real glatos data, use something like below
+#' # rec_file <- "c:/path_to_file/GLATOS_receiverLocations_20150321_132242.csv"
+#'
+#' rcv <- read_glatos_receivers(rec_file)
+#'
+#' @importFrom lubridate parse_date_time
+#'
+#' @export
+read_glatos_receivers <- function(rec_file, version = NULL) {
+  # Read source file-------------------------------------------------------
+
+  # see version-specific file specifications
+  # internal data object; i.e., in R/sysdata.r
+
+
+  # Identify file version
+  id_file_version <- function(rec_file) {
+    col_names <- names(data.table::fread(rec_file, nrows = 0))
+    if (all(glatos:::glatos_receivers_schema$v1.1$name %in% col_names)) {
+      return("1.1")
+    } else if (all(glatos:::glatos_receivers_schema$v1.0$name %in% col_names)) {
+      return("1.0")
+    } else {
+      stop("Receiver location file version could not be identified.")
+    }
+  }
+
+  if (is.null(version)) {
+    version <- id_file_version(rec_file)
+  } else if (!(paste0("v", version) %in%
+    names(glatos:::glatos_receivers_schema))) {
+    stop(paste0(
+      "Receiver locations file version ", version,
+      " is not supported."
+    ))
+  }
+
+  #-v1.x----------------------------------------------------------------
+  if (version %in% c("1.0", "1.1")) {
+    ver_txt <- paste0("v", version)
+
+    col_classes <- glatos:::glatos_receivers_schema[[ver_txt]]$type
+    timestamp_cols <- which(col_classes == "POSIXct")
+    date_cols <- which(col_classes == "Date")
+    col_classes[c(timestamp_cols, date_cols)] <- "character"
+
+    # read data
+    rec <- data.table::fread(rec_file, sep = ",", colClasses = col_classes)
+
+    # coerce timestamps to POSIXct; note that with fastPOSIXct raw
+    #  timestamp must be in UTC; and tz argument sets the tzone attr only
+    options(lubridate.fasttime = TRUE)
+    for (j in timestamp_cols) {
+      data.table::set(rec,
+        j = glatos_receivers_schema[[ver_txt]]$name[j],
+        value = lubridate::parse_date_time(
+          rec[[glatos_receivers_schema[[ver_txt]]$name[j]]],
+          orders = "ymd HMS",
+          tz = "UTC"
+        )
+      )
+    }
+    # coerce dates to date
+    for (j in date_cols) {
+      data.table::set(rec,
+        j = glatos_receivers_schema[[ver_txt]]$name[j],
+        value = ifelse(rec[[glatos_receivers_schema[[ver_txt]]$name[j]]] == "",
+          NA, rec[[glatos_receivers_schema[[ver_txt]]$name[j]]]
+        )
+      )
+      data.table::set(rec,
+        j = glatos_receivers_schema[[ver_txt]]$name[j],
+        value = as.Date(rec[[glatos_receivers_schema[[ver_txt]]$name[j]]])
+      )
+    }
+  }
+  #-end v1.x----------------------------------------------------------------
+
+  # strip data.table and assign glatos_receivers class
+  data.table::setDF(rec)
+  
+  rec <- as_glatos_receivers(rec)
+
+  return(rec)
+}