EditCatch

EditCatchStateType = {
    // Pretty much the same as what you have for EditCatchContextType now
}


export EditCatch = ({navigation, route} : EditCatchProps) => {

  const [editCatchState, setEditCatchState] = useState<EditCatchStateType>(/* initial state value */);
  
  const handleLengthChange = useCallback((length: number) => {
     setEditCatchState((prev) => {
        prev.length = length
        return prev;
     });
  }, []);
  
  const handleSpeciesChange = useCallback((species: Species) => {
     setEditCatchState((prev) => {
        prev.species = species
        return prev
     })
  }, [])
  
  const handleDateChange = useCallback((datetime: Date) => {
     setEditCatchState((prev) => { 
        prev.createdAt = datetime
        return prev
     })
  }, [])
  
  const handleLocationChange = useCallback((location: Location) => {
     setEditCatchState((prev) => {
        prev.location = location
        return prev
     });
  }, [])
  
  const handleAdditionalDataChange = useCallback((additionalData: AdditionalDataType) => {
     setEditCatchState((prev) => {
        prev.additionalData = additionalData
        return prev
     }
  }, [])
  
  renderScene {
      switch (route.key) {
         case 'speciesSize': {
            return (
              <EditSpeciesSize 
                onFishLengthChanged={handleLengthChange}
                length={updatedCatch.length}
                onSpeciesChange={handleSpeciesChange}
                species={updatedCatch.species}
              />);
         }
         case 'dateTimeLocation': {
             return (
                <EditDateTimeLocation
                  catchDate={updatedCatch.createdAt}
                  onDateChanged={handleDateChange}
                  location={updatedCatch.location}
                  onCatchLocationChanged={handleLocationChange}
                />);
             );
         }
         case 'additionalData': {
            return (
               <EditAdditionalData
                  additionalData={updatedCatch.additionalData}
                  onAdditionalDataChange={handleAdditionalDataChange}
               />
            )
         }
      }
  }
}

Obviously not fully working code, but you get the "gist" of it. EditCatch maintains all of the state for the catch being edited, and the three child components only receive the pieces of the catch state they need, plus callbacks to update those pieces of state.