Fish Crow vs American Crow Distribution in FL (4 Viewers)

[SandhillCrane02]

After being asked many times how it is possible to differentiate Fish Crows and American Crows, I decided to make a distribution map for these very similar species. Though it is very difficult to visually distinguish them, it can be possible in some places to determine which species you have just based on the location.
I’m in a GIS class at my university so using what we’ve learned about ArcGIS and dating importing I used research grade observations on iNaturalist to create this map!
Note: the username neil712 is my name on iNat, so if you'd like to follow me there that's where you can find me

 

[Phaethon]

You could probably get better info on this on eBird species maps.

 

[jmepler]

A distribution map is only as good as the data used to create it. It appears that iNaturalist is lacking in bird data, at least as far as crows are concerned.

Based on your map, one would assume that a crow sighting near Gainesville would likely be an American Crow. The attached image is Fish Crow sightings from eBird in the Gainesville area. As you can see, there are a lot more sightings in the area than iNaturalist would lead you to believe. While American Crow is reported more often in the area, there is still a substantial number of Fish Crow reports. Too many sightings to confidently judge which species based solely on location.

 

[MiddleRiver]

Great effort and nice graphics Neil ;-)
It would be interesting - with your graphics and GIS skillzz, to see the eBird data taken to the next level...

 

[Jim M.]

It appears that iNaturalist is lacking in bird data, at least as far as crows are concerned.

Yes, I almost never submit bird data to iNaturalist. You generally need a photo for each record you submit (there are some exceptions), it doesn't allow you to record numbers of individuals observed, and you can't submit complete checklists which would indicate that a species was not observed. EBird is far better for bird data. But I use iNaturalist for all the other taxa.

 

[opisska]

Yeah iNat sadly can't be really used much for any bird-related research because it's not used much. I put my birds there, but I am not a "systematic birder" - so its setup suits me. I am not sure about the US, but here, iNat bird record distribution is heavily influenced by the presence of individual people putting birds there in an area, because there are so few.