What is the species filter threshold?

[ceperman]

The current species list mentions that the species filter threshold is 0.03. What does this mean and should I be interested in adjusting it?

[Mattk70]

When you're using the location list, this threshold represents the cut-off frequency, below which species are excluded. In BirdNET Analyzer, this is the --sf_thresh option:

--sf_thresh, Minimum species occurrence frequency threshold for location filter. Values in [0.01, 0.99]. Defaults to 0.03.

Should you adjust it? Well, if you lower it, you'll see more birds on the list, and vice versa. The accuracy of the filter is questionable (you get surprising seabirds on it, but Owls are apparently extremely rare!). See here for more details: kahst/BirdNET-Analyzer#296

In my opinion the main uses of the location list are:

1. It's a good quickstart, so BirdNET doesn't hit you with a swathe of global species
2. In Chirpity, it's a good way to generate a boilerplate for your custom list. It's far easier to refine a list with 300 or so species, than to start with the 6500+ that BirdNET knows about.