Water temperatures permitting, the spawning season for course fish, i.e. fresh water fish other than salmon and trout, runs from March through June.

Having been an enthusiastic fish watcher since I was knee-high to a tiddler, the title “course” infers “inferior” but whereas salmon and trout are justifiably king and crown prince of fish, there are many course fish worthy of respect.

When very young, I fished with a net for sticklebacks (pictured). Another method involved tying a small worm onto a piece of cotton and lowering the bait slowly into the pond margin.

Before long, a stickleback would seize the worm at which point a gentle raising of the cotton would ensure the fish didn’t let go and was easy to transfer to a jam jar.

In early March, I liked to sit in a low tree overhanging the water and watch fascinated as sizable female pike cruised among marginal water plants, shadowed by smaller males or “jacks”.

Transparent, pale yellow, caviar sized eggs were laid on the plants and I would collect a few to raise in an aquarium.

Upon hatching, the defenceless fry hid on the bottom for a few days until their bulky yolk sac was absorbed and they became free swimming, feeding on small invertebrates.

So greedy were they that I recorded finding an inch long pike with the tale of another poking out of its mouth. He had swallowed his twin whole.

By July, a stroll along the Thames reveals shoals of billions of tiny fry of assorted sizes hugging the bank for mile after mile.

Most of them fall prey to predatory fish, grebes and herons long before reaching maturity.