Moth trappers and iNat! (UK-focused)

I’m an avid moth trapper and love going through people’s hauls on here to get as many verified, as well as honing my own ID skills. It’s a big moth summer and people are catching some great species.

But please! You don’t need to post everything on your photo reel, and each and every individual Large Yellow Underwing, Riband Wave etc from the same night as separate entries (unless you really need ID advice for individuals you’re not sure on). [edited for clarity]

And unless you genuinely don’t know the species, please add your ID when you post them!

There’s also some cryptic species which will almost always get verified to complex rather than species - I put together a guide here Cryptic Species of Macromoth

As much as I don’t want to put people off using iNat of course, it’s worth finding out your local recorder and if they take iNat records from iRecord or not, or if they’d like a separate spreadsheet, or you risk your records not going into national schemes - List of moth recorders

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I have to confess that I did post something like 68 observations for like 3 species some days ago. In my defense, they were Dun-bars and some Hoplodrina sp. (like the Uncertain!) which have a lot of variation in colour and pattern. So, A) I didn’t know a priori that they were the same species and B) I thought it would be helpful for the community to record all these variations. I haven’t uploaded any more since then (even though they’re the most abundant species in my moth trap every night)

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It’s tricky with some species when you’re starting out as they’re so variable and it takes time to realise the variance and the key ID features (I don’t think two LYUs ever look exactly the same for example), and I certainly wouldn’t want to deter anyone if they genuinely don’t know.

I also get the idea of showing some variety and logging aberrations and unusual ones.

Individual organisms observed at different times should always be separate observations, and should never be lumped together.
It’s a perfectly acceptable use of iNat to observe multiple of the same species (even so many that it seems unreasonable to others).

As an IDer (albeit neither of moths, nor specifically in the UK) I understand that it can be frustrating to see the same species over and over again, but that’s just the way it is. Some species are so common that they sometimes make up the majority of observations for a taxon.

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I think you’ve misunderstood me, I totally agree with you and meant posting 30 individual posts of LYU from the same trapping session. I’ll tidy up my language to avoid ambiguity, I realise I worded it clumsily.

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I believe there’s an inherent difficulty here given what constitutes an individual record differs slightly between iNaturalist and other platforms in the UK (e.g. iRecord). On iNat, each observation is meant to represent one single subject organism (i.e. one individual), whereas on iRecord as recorders we are encouraged to submit one record per species per time and place. So if you got seventeen Cosmia trapezina at your moth trap one night and wanted to record these, correct practice – technically speaking – would be seventeen separate records on iNaturalist but one record (with quantity = 17) on iRecord. Technical rules aside, I think in most cases few people would have a huge issue with you uploading multiple individuals of the same species as one observation on iNaturalist (this happens all the time with plants, for example: where is the ‘one individual’ with grasses?). Even if you were to upload 17 observations of the same species from the same time and place, there are statistical tools which should filter this out when end users come to use the data. The only risk in doing 17 observations is that you’ll irritate iRecord verifiers (and having spoken to many, some do find this very annoying).

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That’s an interesting way of looking at it Joss I hadn’t really considered, and all this is just my personal opinion and I’ll always bow to others. I’ve had nights with over 300 LYUs so that approach would be interesting!

I am starting to see more and more why many iRecord verifiers ignore iNat records, as you say the two methods are inherently incompatible.

If I have learned anything from being on iNat for 13½ years, it’s that everyone uses the platform in unexpectedly different ways, while at the same time there is a tendency for everyone to assume that everyone else uses it in a similar way that they do!

I do get that there is limited identifier time and there must come a point at which IDing thousands of observations of the same common species is no longer a wise use of that resource. However, I would not be so quick to assume that posting 17 riband waves from the same trapping session is undesirable.

For somebody interested in the simple geographical distribution of riband waves (to stick with that as an example), I agree there is indeed little benefit to having observations logged for individuals 2 to 17 from that trapping session. Similarly for somebody using iNat to log what species they have seen, the extra observations don’t add much. But for somebody interested in what time of year riband waves mostly appear (perhaps as part of a study on whether climate change is causing them to emerge earlier) it is important to know on which nights they were numerous and on which nights there were only a few. For somebody studying subtle differences in wing pattern between individuals found in two different regions (perhaps with a view ultimately to describing one as a new species or subspecies) then as many photographs as possible of different individuals are needed. There are doubtless ten thousand more different ways in which iNat data is being used that neither you nor I are aware of, so I think one has to be cautious in assuming that data points that may seem excessive to some users are not in fact very valuable to others.

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I absolutely agree two points there -

Not everyone is confident in the ID of a Riband Wave against confusion species may want confirmation on most/all and of course should post as many as they want.

That quantity data is hugely important as well as presence (although there is a very underused ‘quantity’ filed in iNat, and by that argument it’s important to log the numbers of the 30 that flew off before you got the camera out too).

But you also make some very good points about the variation of uses of iNat data (which I suppose also includes training the computer vision). Maybe I’m coming torwards this with too much of an ‘iRecord’-style viewpoint.

iNat needs to encourage mid-level identifiers - so the taxon specialists are relieved of the grunt / grudge work - and can focus their attention on the more interesting obs.

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I think I probably count as a mid-level identifier, and I’m happy beavering away on the LYUs, don’t get me wrong.

It’s been an educational discussion this, and it really shows the complexities of iNat and its data flow.

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