DART PIT Tag Adult Sampling at Lower Granite Trap Methods

The Adult Estimation Program at Lower Granite Dam (and other locations)

Developing the tag list to use for upstream detections is complicated because of ladder operations and the sort-by-code PTAGIS uses to opportunistically capture fish for specific processes. The ladder trap operates 24 hours a day, opening and closing systematically 4 times per hour (controlled by a computer). All fish migrating past the trap (regardless if they have a PIT tag) are forced into the trap box during the sampling periods. Technicians then work up the fish 2-3 times per day, PIT tagging all wild fish that do not have an existing PIT tag. Any fish with a PIT tag is scanned, called a recapture and released. All fish that are systematically collected are part of the valid sample for upstream detection. However, the trap also has sort-by-code capabilities that allows researchers to request PTAGIS automatically collect a PIT tagged fish if detected swimming upstream by the trap. These fish can come into the trap during the sample collection period as well as when the trap is not "sampling". Any PIT tag that is collected outside the sample period is not a part of the "Valid Sample" and is not valid for use in the upstream tributary escapement calculation. Because crews are working up all the fish at once and include many species, rearing types, recaptures, SbyC fish, it is not know until later what fish is valid or not.

There are several sources of information needed from PTAGIS raw interrogation files and PTAGIS datasets to determine the valid sample list:

  • Tagging - From tagging files (tagging location LGRLDR)
  • Recapture - From tagging files (recapture location LGRLDR)
  • SbyC fish and period - From raw interrogation files for Lower Granite Adult Ladder
  • Sampling Period - From raw interrogation files for Lower Granite Adult Ladder

Sample Time and Rate Query includes the following information from the Multimon files for Lower Granite Adult Ladder:

  • Date: Calendar date of sample period, SbyC event, or fish detection.
  • Year: Year of sample period, SbyC event, or fish detection.
  • DOY: Day of year of sample period, SbyC event, or fish detection.
  • SampTime: Total seconds in day for sampling periods. Sample periods that span days are split and seconds are applied to the individual days.
  • SbyCTime: Total seconds in day for SbyC events. SbyC events that span days are split and seconds are applied to the individual days.
  • TotalTime: Total seconds in day trapping occurs (SampTime + SbyCTime).
  • SampTimeInclusive: Total seconds in day for sampling periods. Periods are inclusive of ending second (i.e., +1 for each period). Sample periods that span days are split and seconds are applied to the individual days.
  • SbyCTimeInclusive: Total seconds in day for SbyC events. SbyC events are inclusive of ending second (i.e., +1 for each event). SbyC events that span days are split and seconds are applied to the individual days.
  • TotalTimeInclusive: Total seconds in day trapping occurs based on inclusive method (SampTimeInclusive + SbyCTimeInclusive).
  • #Samples: Number of sample periods in day.
  • #SbyC: Number of SbyC events in day.
  • #Close: Number of actual gate closings in day. This can differ from #Samples+#SbyC if an SbyC event is contained within a Sample period.
  • SecondsInDay: Total possible seconds in day for sampling, 172800 (24 hours * 60 minutes * 60 seconds * 2 sample units).
  • Rate: Rate set in trap operations.
  • ActualRate: Actual rate based on TotalTime (sampling time and SbyC events) and SecondsInDay.
  • ActualRateInclusiveTime: Actual rate based on inclusive method TotalTimeInclusive (sampling time and SbyC events) and SecondsInDay.
  • TotFishTrap
  • TotFishSamp: Total pre-tagged fish in sample periods in day.
  • SampNotSbyc: Pre-tagged fish in sample periods in day that are not SbyC coded fish.
  • SampSbyc: Pre-tagged fish in sample periods in day that are SbyC coded fish.
  • TotSbyC: Total pre-tagged fish in SbyC events in day.
  • SbyC: Pre-tagged fish in SbyC events in day that are coded SbyC fish.
  • SbyCEntrained: Pre-tagged fish in SbyC events in day that are not coded SbyC fish. Fish are entrained in the trap by SbyC events triggered by other fish.
  • SampMaybe: Pre-tagged fish that may be part of sample period depending on gate open/closing speed.
  • SbyCMaybe: Pre-tagged fish that may be part of SbyC event depending on gate open/closing speed.
  • NOTSamp: Pre-tagged fish detected at coils 28, 26, 24, 22, 18, 16, 14, 12 that are not part of a sample period or SbyC event. Maybe fish are not included in this total.
  • ALLPit: All pre-tagged fish detected at coils 28, 26, 24, 22, 18, 16, 14, 12.

PTAGIS Resources