Fishing a estuary for flats is a licence needed?

I've found a estuary that seems very fishy. It is about a half mile away from the mouth of the river. Where the tide pushes back the fresh water and fills. There is sea weed and sandy mud bottom. I'm wondering if I would be breaking the law by fishing here for flounder, ( or any flats) this estuary has got sea trout and maybe salmon running through it to the river. Also is it possible that the shore line can be private property ? I don't want to get in trouble over a few fish but I seen this mark and it would be fishable when all other marks are not. Also would the flounder wait in the estuary all year round.

Sounds like you could be describing the Slaney estuary. It is fishable for flats and sea fish right up to Killurin which is about 3 miles inland. As far as I know, if the water is mainly sea water and you are fishing for sea fish, you do not need any licence. I am using the Slaney purely as an example

Sounds like you could be describing the Slaney estuary. It is fishable for flats and sea fish right up to Killurin which is about 3 miles inland. As far as I know, if the water is mainly sea water and you are fishing for sea fish, you do not need any licence. I am using the Slaney purely as an example

Thanks very much for the feed back Kevin , its not the slaney I'm talking about but if you can get flat fish in winter up to 3miles inland I should be able to wangle one out . The mark is on the tide line but there is a lot of fresh water at the moment so I'm wondering if I should leave it till it drys up a bit. Also I'm planning to use lug for bait but is there any other bait that would be good in a river mouth/ estuary? And another question if its alive with crab is there any way to bet them

Most estuaries will hold a few Flounder, late Winter will probably be better, when the Bigger fish return from spawning out in deeper water. Try fishing on a really cold evening when the crabs will be less mobile.

Also I'm planning to use lug for bait but is there any other bait that would be good in a river mouth/ estuary? And another question if its alive with crab is there any way to bet them

a friend of mine has caught flounder outside cappoquin while fishing for trout with maggots and earthworms,they were no bigger than a coffee jar lid tho' and thats miles and miles from the river meeting sea in youghal...

Sounds like a good spot determined dan. Have wondered that myself about licence in one or two places near me. Must check it out with the local know alls