Case in point: I was recently reading a short article about the hatches that can found on one of my local streams. Well, it didn't take me reading too long before I was asking, "which stream is this supposed to be?" Hardly any of the info in the article was correct. Now, they did manage to mention a few of the hatches that occur on my stream, so it wasn't completely false information. However, they listed at least a half dozen hatches that DON'T occur on this stream at all.
In addition to adding hatches to my stream, some of the info about the hatches that actually do occur was wrong. For example, it mentioned that the Brown Drakes hatch only at night. They do hatch at night, but they also hatch in the late afternoon & you can fish this hatch while the sun is still out. They mention that the Brown Drake is a minor hatch but, in truth, it is one of the major hatches of this stream & by far the largest, physically, which brings out the bigger fish into the light of day.
This article was heavy on mayfly info, but on this stream, caddis are more important for most of the year. There are numerous different caddis hatches throughout the season on this stream. This article listed only two caddis hatches!!!
The article (surprise, surprise) appeared on a website that sells flies. The company is located far away from my stream, too. Plus the article wasn't credited to any author. All this should send up red flags when you read stuff like that.
Well, you can see what's happening here: they're listing too many hatches in the article in an attempt to sell more flies. They're hoping you'll buy a dozen of each fly listed for your trip to this stream. Is that right? At best it's irresponsible. At worst it's a scam.
As I always say - nothing trumps local knowledge. So if you're planning a trip to a new stream do your research. Find a fly shop local to that area. Read the fly shop's website for info. Call ahead to them & explain that you'll be in the area & ask for their advice. When you do go to that new stream, stop in at that fly shop to thank them for their help & buy something from them - maybe those flies you thought about buying online. It's always best to go to the source for info, rather than believing anything you read online. Not everyone is trying to take advantage of you, but there are some bad eggs out there. When in doubt, or if something just doesn't sound right about a new stream, ask a local. I've found that most local anglers want you to have success & enjoy the streams they call home.