tag:blogger.com,1999:blog-4819377074550717188.post5935617974038486636..comments2023-12-24T02:53:29.472-08:00Comments on Syrphing Time: A rationale for caution in photographic identificationRoger Morrishttp://www.blogger.com/profile/18319989613630200252noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-4819377074550717188.post-12275033902011426932015-09-05T03:59:59.464-07:002015-09-05T03:59:59.464-07:00A very thoughtful and considered post. I would con...A very thoughtful and considered post. I would consider myself probably in category two of the biological recorders (observing for pleasure but wanting the names to be accurate), but also with elements of category three (once I am satisfied that I have accurately identified something then I want to contribute that record). I also have a local area that I put more effort into actively recording than I do if simply out in a new area.<br /><br />What I mainly wanted to say was how useful I have found the Introduction to British Hoverflies WildGuide. In particular the categorisation of species into identifiable in the field/require a closer look or specific features to be observed/requires microscopic examination have been very helpful. It has allowed me to have more confidence in identifying distinctive species and prevented me from assigning trickier ones to species level with false confidence. Also by researching key features at home, I have been able to take photographs from the right angle or of the essential areas to split species pairs.<br /><br />If observers (and scheme administrators) have a clear idea of what can and cannot be identified solely from photographs, then that will go some way to helping with the integrity of the data. I hope that the approach used in the WildGuide can be adopted by authors of guides to other taxa in place of the disheartening phrase "many similar species"!<br /><br />Regards,<br /><br />JamesJames Emersonhttps://www.blogger.com/profile/04895693455349558444noreply@blogger.comtag:blogger.com,1999:blog-4819377074550717188.post-18772462684496257992015-09-04T03:13:41.462-07:002015-09-04T03:13:41.462-07:00A nice exposition of the groups and issues involve...A nice exposition of the groups and issues involved. One idea that could help is to be able to add confidence level to records. None of the software I've used or the schemes, surveys and organisations to which I submit data, allow this.<br /><br />I've added a status code of U-Uncertain to my Wildlife Recorder databases (these don't cover hoverflies, but apply to birds, dragonflies, mammals, butterflies and moths, dragonflies, reptiles/amphibia and plants). Even such a binary flag is useful - but only to me if the destinations of the data don't use it.<br /><br />So in many cases, I make up my own rules. I'll illustrate with birds, which I have recorded since the 1970s. Don't tell the BTO, but when you conduct a Breeding Bird Survey, sometime you hear only a very brief call, or get only a glimpse of a bird. I generally record it on the survey if I am 80% sure or more, and the species is found on the survey site. (eg The flap of a wood pigeon's wings on take off from a tree is pretty distinctive, but if not seen it could just possibly be something else). If I am less sure or it is unusual on the site, I simply keep it in my own records, usually with an appropriate comment as they will reach local and national records.. But that's just me - every recorder must make some such judgements some of the time.<br /><br />The only two times I reported birds regarded as locally rare, my reports were rejected although in both cases I was absolutely sure as they were very distinctive species, and in one case had corroboration in a nearby county later that day. The regional rarities committees didn't approve my descriptions, or maybe trust me, so those records are basically lost. If they had included them as 'Likely but unproven' they could be telling us something.<br /><br />As Roger says, the 'strict' recorders will omit anything uncertain altogether. But it can be useful indication of something changing or previously unobserved. If systems, over time, could be adjusted to allow the degree of confidence - or just Certain or Uncertain - to be recorded, particular analyses can choose whether to include less than 100% or not. In reality, many inexperienced recorders in a particular group will record sightings, which therefore appear 'certain, many things which are incorrect - it would be better to allow openness.<br /><br />A similar idea is to allow more recording at family level e.g. Syrphus sp. This is not helpful for individual species - of course - but can give better indications of overall numbers and distribution of such groups.<br /><br />There are many challenges in non-professional biological recording, which I regard as being still in its infancy in many ways; this is just one.Paul Seligmanhttps://www.blogger.com/profile/18370438884642104930noreply@blogger.com