Rainbow trout

Identification

The rainbow trout is a powerfully built salmonid with a torpedo-shaped body. Its signature feature is the broad pink-purple stripe along the flanks — the 'rainbow' that gives this fish its name. The back is olive-green to blue-grey, dotted with small black spots that also extend onto the tail fin. The belly is silvery white. An adipose fin behind the dorsal fin reveals its kinship with salmon and brown trout. In the Netherlands, they are typically caught at 30-50 cm, though stocked specimens can exceed 60 cm.

Behavior & ecology

Rainbow trout originate from western North America and in the Netherlands are found almost exclusively as stocked fish in commercial trout ponds and put-and-take waters. Wild populations are extremely rare because the species barely reproduces in Dutch waters — the water is too warm and lacks suitable gravel beds for spawning. Rainbow trout are active predators feeding on insects, crustaceans, and small fish. They are most active at water temperatures between 10 and 16°C and seek deeper, cooler layers during warm summers.

Fishing techniques

In the Netherlands, rainbow trout are almost exclusively caught in commercial trout ponds. Popular methods include:

• Fly fishing — the classic trout method. Dry flies work well in spring and autumn during insect hatches, wet flies and nymphs year-round
• Spinning — small spinners (size 0-2), mini crankbaits and trout spoons are effective, especially on freshly stocked fish
• Bombarda/sbirolino — a weighted float that lets you present light lures or powerbait at distance
• Powerbait/dough — fished on the bottom or suspended with a buoyant bait; popular with beginners and very effective in put-and-take ponds

Use light tackle: a 2-6 gram rod with 0.18-0.22 mm line. Trout are wary and line-shy.

In the Netherlands

Rainbow trout are not native to the Netherlands but have been stocked in commercial fishing ponds for decades across the country. They are a popular sport fish due to their spectacular fight on the rod. There is no closed season or minimum size because the species is not considered native, and populations are entirely dependent on stocking. The species is not on the Red List and has no protected status in the Netherlands. Trout ponds are often open year-round, allowing fishing for rainbow trout even in winter.