Hi i don't have experience of the essex area but i live in the north devon area and fly the estuaries for time to time. the main species i target is bass

although there are usually good numbers of mullet (not the easiest to target with a fly!!!! beware!!!!!) and makarel (yet to catch on fly but go like rockets on very light gear

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Being in the estaury the majority are school bass although a keeper does turn up from time to time but i actually put them back. A couple of points first safety(sorry to sound like a jobs worth

) estauries can be dangerous places the water moves in very quick as ideally you want to be fishing either do to low tide and on the push. Estauries tend to have a habit of not filling up evenly and you can find yourself in knee deep water whilst a little way behind is waist deep fast running water. point 2 -Use barbless hooks, as the vast majority are schoolies try to unhook in the water and let them go asap watch out for the spinny dorsal fin and gill covers. I would suggest wearing chest waders although when warm enough i know people who wear shorts, a line tray is useful can easliy make your own to. take minimum kit and travel. the area i fish primarily in the estaury is around low tide rocks and muscle beds. There are often pools left filled which from time to time have fish in them

however these are often quite warie. Don't use big fancy flies most of the success i have had comes from using small patterns usuaully with a small head with various colour strands of silver, blues etc. some people using trout lures just try a few out, obviously they won't like the salt. I need to stop

check the area out at low tide look for holding areas signs of fish, other fisherman, i would like to think most would be friendly explain your new to it. all the best cheers jon