In a statement issued by the company, Lisa Williams, PR and Marketing Manager, said:
"Train services nationally have been temporarily reduced to reflect reduced demand while continuing to cater for essential travel.
"Between Whitby and Middlesbrough from Monday January 18 there will be four trains each way on weekdays, at 06.36, 08.45, 16.00 and 19.44 from Whitby and at 04.58, 07.04, 14.04 and 18.00 from Middlesbrough.
"Sunday services are unaltered.
"In addition, the Esk Valley line will be closed entirely for nine days from Saturday 13 to Sunday 21st February for major engineering work, with replacement bus services."
For further details and for other revised services go to northernrailway.co.uk/travel/timetables.