We certainly have never seen a fly pattern change the game the way the Chubby Chernobyl did. It would be hard to find a fly shop in the west that doesn't have multiple fly bins dedicated to these flies. Also it would be rare to find an angler in the trout states that isn't carrying a few in their box.
This super foamy pattern developed 90's by a group of Utah anglers experimenting with foam and polypropylene rope to mimic the black crickets in the canyons out there. Previous to this foam had not been a regular material fly tyers kept at their bench. The experimental material proved innovative when trout started exploading on them. The Chernobyl Ant was born when a dubbed body and rubber legs added and started crushing fish. The name "chernobyl" was born when a couple of Green River guides used a very popular 90's slang word and described the fly a "the f*****g" bomb."
When the chernobyl ant was entered and started winning the Jackson Hole One Fly Tournament the pattern popularity exploded. Will Dornan owner of Snake River Angler tweaked the pattern and added the large dubbed body and highly visible polypropylene wing and the modern day "Chubby" was born. The wing helped anglers be able to see the fly at distances but the real bonus was it made the fly land correctly on the water.
About 20 years ago the "chubby" made its way to Oregon through the once dominate Idylwilde Fles. Their rep at the time Eric Neufeld started fishing the samples on the Deschutes with Fly and Field owner Scott Cook. As the story goes they were out on the Deschutes early May when they struck gold. At the time the Deschutes Salmonfly hatch started a month later, with recent changes to the dam the season was changing. The perfect conditions arose with a stormy morning that warmed up and got muggy in the afternoon. The salmonflies were thick and were all over the water. Clearly the redbands had never seen the likes of chubby as they were throwing themselves at the foamy goodness.
After the day Scott brought as many chubby's into his shop as Idylwilde could get him. John and Amy Hazel owners of Deschutes Angler in Maupin got their hands on them and the secret was out.
Our number one selling fly here at Fly and Field Outfitters is easily the "Chubby." We stock it in several different sizes, colors, and variations. This pattern will be seen year round on Central Oregon waterways.
The Chubby is a great attracter pattern with such thick foam that it works perfectly with dry dropper set ups. The pattern has developed so much that some patterns are tied with double foam bodies so they can support the weight of really heavy tungsten jig nymphs. Turning over these large fluffy patterns is done best with short stout leaders. A 7.5' 2X tapered leader does the trick here or an Airflo 5' Poly Leader.