The clues....

ACROSS

1 Frog in the making (7) 5 It causes the sea to flow back from the coastline (3,4) 10 Stotz has generally replaced this weight ... found in Swinsty lake (4) 11 Low, flat land area by a river at risk of being underwater after heavy rain (10) 12 Remove too large a proportion of catches, leaving a lake etc. depleted of stock (8) 13 Northants market town on the Nene (anag. of ‘nodule’) (6) 14 Famous angling location on the Avon, near New Forest (anag. of ‘rod owing’) (8) 16 e.g. a twist in a line (4) 18 Devices for casting groundbait (abbrev.) (4) 19 Reservoir near Tring, Hertfordshire (anag. of ‘towlines’) (8) 22 A line’s strength is its breaking ___ (6) 24 A raised road across water, which might be cut off at high tide (8) 25 Angler’s aid in the dark (5,5) 26 Dad’s Army character’s fish! (4) 27 Small fin between the tail and dorsal fins (anag. of ‘is a dope’) (7) 28 Secured by means of e.g. a grinner (7)

DOWN

2 e.g. moving around and feeding (anag. of ‘I’ve cat’) (6) 3 Glare-reducing glasses (9) 4 (of a biting fish) raising the line and shot of the bottom (7) 6 ___ on Avon, village between Stratford and Evesham (7) 7 Very sweet bait additive (anag. of ‘Latin’) (5) 8 Making a hole e.g. in boilie (8) 9 Term for a long narrow inlet of sea in Scotland (4) 15 Viscous liquid ... seen in boilies (3) 16 Type of small pole cup (anag. of ‘rod kept in’) (6,3) 17 It might bring cold weather from Siberia to Britain (4,4) 19 Small, edible marine snails (7) 20 Somerset town on River Tone (anag. of ‘not tuna’) (7) 21 Angling gear made by footballer? (6) 23 It flows from the west into Ladybower Reservoir (anag. of ‘posh A’) (5) 24 Open-ended mesh swimfeeder (4)