I recently received a request from a representative of the Texas Nature Trackers to provide “accurate” location data for three of my iNat observations of Red-shouldered Hawks:
I had taken all three with my GPS-equipped camera, and all had been rated as Research Grade by iNat. Moreover, they were all taken in the Houston Arboretum or Buffalo Bayou Park Project areas. Needless to say, I was really confused why there was any question about the accuracy of the location data included with each.
Here is observation 19576954 from the Houston Arboretum:
What am I missing? How does one get the accuracy of one’s observations’ location accuracy recorded? Can it get any more accurate than the data provided by my camera’s GPS? Moreover, what does Community Curated – at the top of the right hand column – mean? Why would any group question the accuracy of iNat’s indication that it is Research Grade, which is never given, in my experience, when location data is not provided?
This is clearly not a big issue, but I’m really puzzled why it is an issue at all!
I belive in this context, community curated means “curated by the community.” These are named places that were created by iNat users rather than downloaded from an external authority, like “Texas” would be. I think the “Standard” (non-community) places come from Google Maps but I’m not 100% sure.
Location accuracy (which should more correctly be called “precision”) reflects how certain you are that the organism was present at the exact coordinates you uploaded. In observations that have an accuracy measurement (like this one), it shows up as a circular region around the pin. The “accuracy” is the radius of this circle: “I’m sure it was within 10 meters of these coordinates,” etc. I think some GPS’s record the accuracy (really, precision) of their geolocation data automatically while others don’t. You can also set the location accuracy manually.
The accuracy can be any size, so it’s possible to have a circle that encompasses a whole state if you want. That would mean, essentially, “I saw it in this in this state somewhere, but I’m not sure where.” In this case, the coordinates of the pin are not very meaningful as a statement of where the organism actually was. Sometimes when I photograph something while hiking on a trail, and my phone’s GPS didn’t catch the location, I’ll make the accuracy circle quite large to encompass a large portion of the trail, just to be safe.
The person who contacted you is probably asking for you to add location accuracy data to these observations, so they can know whether you saw the hawk at exactly that spot in the arboretum, somewhere in the arboretum generally, or somewhere vaguely in the vicinity of Houston.
I think what they are referring to is under details that states:
“(Accuracy: Not Recorded)”
This means the accuracy of the GPS unit. There are many factors which affect the accuracy. Buildings or tree cover can block the signal from some of the satellites. The position in the sky (if directly overhead or near the horizon the accuracy will not be as good), There are expensive receivers that can get down to sub centimeter accuracy. The accuracy of the unit can change over time because the satellites are not in a stationary orbit as well as proximity to buildings and other factors. You may be able to find documentation as to what accuracy your GPS unit is capable of.
It is probably safe to say that your receiver will have an accuracy of 10 meters or better. Some units will calculate the accuracy, otherwise you probably won’t know.
There is nothing wrong with not recording the accuracy if you don’t know. It has nothing to do with obtaining Research Grade. It is really not a big issue.
Sometimes people doing research will want to only use observations within a certain accuracy range.
If you edit your observation you can add the “Accuracy” in the location section.
Thanks for your explanation! I have naively been ignoring the fact that the location of the camera given by GPS is not the same as the location of the subject of the photo.
Unfortunately I’m a slow learner. Could you please tell me where I can find the instructions for how to ensure that the accuracy of the photo is properly documented?
i don’t think you really need to worry about the recording an accuracy value if your device isn’t already capturing it. i know some folks will come along and suggest that you need to add an accuracy value, but honestly, i would just ignore such folks. there are no instructions to “properly document” because there is no standard way to document.
if you’re still interested in the various ways to get an accuracy value, my understanding is that iPhones can capture a horizontal positioning error that gets stored in your photo metadata. or if you use the iNat app (either Android or iOS), the app can calculate an accuracy value when you make the observation on the app in the field. sometimes if you manually select a location based on a place name, you end up with an accuracy value that represents the radius of a circle that fits around what Google believes to be the boundaries of the location. beyond that, you’re probably entering the accuracy value yourself, and how you decide what the accuracy value should be is sort of just up to you at that point (a guess), unless you’re carrying an external GPS device that is measuring this, and you’re recording that value separately somewhere.
you’ll note that these methods for determining an accuracy value are very different. so simply adding a value doesn’t necessarily increase the scientific usefulness of your observations. in fact, it may make the quality of the data worse, if you just make up values. so, again, i would just ignore. chances are whoever is requesting the information can’t actually explain to you why they need the value or what kind of variation exists within the observations in the system.
standard places are continents, countries, states, and counties (or equivalent). iNat gets these – names and boundaries – from either GADM or the US Census Bureau, and may make small tweaks, as necessary. the last time these were updated was probably 5 years ago, and there are known issues in some of these places.
I think all pictures in iNat are by default community curated. There is an option to opt out of it, and that may exclude the photo from research grade status. I’m not sure on the last part. It is normal to have people look at pictures and ask questions about it.
You can give an assurance to the person you are communicating with that the coordinates are accurate. Birds fly around. It does not really matters if the data are extremely accurate. There are times when the locations of birds need to be veiled even, as due to nesting. Over here, hordes of photographers may appear when a rare bird arrives.
In the case of observations like this, you could click on Edit observation, zoom in on the map, and insert a value for “Acc (m)” that is large enough that you are sure the organism was within the circle shown on the map - see an example below of what will appear when you click Edit. Some devices will record this Acc value automatically with photos, but if not, I would not assume its value without confirming on the map using trees, buildings or other landmarks in the satellite imagery.
A general approach is to google your device name and “gps accuracy” or similar to see whether the device stores an accuracy value in the EXIF data of files.
I did this for a Nikon P900 (what it looks like your shooting with based on iNat’s display of exif data), and it doesn’t appear to record a value for GPS accuracy in the exif: https://www.dpreview.com/forums/thread/4212067
So if you want this, you’d need to enter it manually. I do this frequently and just “round up” (ie, err on the side of making the accuracy larger to hopefully be sure to encompass where I was when making the observation).
Adding my two cents: For those who use the iNat website bulk uploader, you can set multiple observations to a predefined accuracy level. Just select them all using Shift-click…
Afterwards you can edit the accuracy measurement for some you might be more or less confident about. I use my phone camera, so there’ll be the occasional stray observation with the coordinates way off that I have to correct. You can also go through and do it manually, but I find this can help speed up the process.
I agree that this can help speed things up, but if you are using a phone camera, it is probably possible to have it automatically record accuracy. Now, folks should probably check those values because they are sometimes way off as you mention, but having a starting accuracy value for observations without having to bulk edit will speed things up even more!
