Ryanair is reducing its Shannon-based aircraft numbers from six to four this summer and cutting jobs there from 300 to 200.
The 100 staff affected will be transferred to some of the airline's other bases.
This will have the effect of reducing its route network at Shannon from 30 to 25 routes.
It will also cut its Shannon flights from 136 to 116.
As a result Ryanair's traffic at Shannon will fall from 1.9m passengers year to 1.2m.
The airline's CEO Michael O'Leary blames the introduction of the €10 travel tax for the reduction, saying it is already having a damaging impact on forward bookings from March.
