A brief visitation at midday by around 80 BHG's over the boardwalk pond (which quickly re-located to Maes Llyn pond) was coincidental with my receiving a copy of the Cors Caron birdlist for 1979 prepared by P.E. Davis. In those days he saw c300 pairs breed with occasionally up to 1200 pairs! Also breeding then were up to 30- 40 pairs of Curlew and 20-40 pairs of Snipe with 12 pairs of Redshank ( one currently on the flash in front of the Waiting room).
But the herons in those days were not resident breeders as they are now and Goshawks were a rarity so win a few, lose a lot …tale of our times.