Anax papuensis

Australian Emperor at Fyshwick, ACT

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Identification history

	Anax papuensis	22 Sep 2020	HarveyPerkins
	Anax papuensis	22 Sep 2020	RodDeb

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User's notes

There were many in total around all the hides and water edges along with Wandering Perchers and probably others that could not identify or photograph successfully

6 comments

HarveyPerkins wrote:

22 Sep 2020

Hi - there's no doubt these two photos are Anax papuensis; but 20 is a large number for them, unless they were spread out over a fair area. There would almost certainly have been much larger numbers of Tau Emeralds based on what I've seen so far this season. Despite the size difference, they can be difficult to differentiate if not seen well, or seen only at a distance.

RodDeb wrote:

22 Sep 2020

Thanks Harvey, there was a huge amount of mainly dragonflies in front of 3 hides it was amazing but so difficult to get photos as they were flying around rarely stopping, they did hover for a bit. There were quite a few noticeably larger Dragonflies which we may have thought were these but as you say were probably a mixture with Tau Emeralds. Unfortunately none of our photos showed Tau Emeralds clearly so that is what our estimate was based on. They sure can be difficult to tell in distant photos though. The estimate is for all over the Wetlands where we saw them not just in this location.

HarveyPerkins wrote:

22 Sep 2020

If your count covers the whole of Kellys Swamp, I have no problem at all with an underestimate of 20!

RodDeb wrote:

22 Sep 2020

The count covers the whole area we did on that day. Apologies for any confusion. It is difficult when you have to put just one location for a photo and the count is for all you saw, especially when we only got one good photo. How do we do it in the future? As for some other listings when I put multiple photos they are of the same species of insect or birds and usually put the count for how many we saw on the day at that place/visit not just the one location. Is this the correct way of adding the counts? Appreciate your help and guidance.

HarveyPerkins wrote:

22 Sep 2020

I don't know that there is a "correct" way to account for these variables, and I know the question gets raised not infrequently. Personally, as the record is tagged by its geolocation, I'm usually very conservative, and would normally restrict my 'observed number' for the record to within close proximity of the photographed individual - for dragonflies, say no more than a 25 m radius. But I keep fully detailed records for my dragonflies, so any photos I add to the NatureMaps have a number relating to just that immediate spot, and my full records show the total number for whatever area I surveyed. If I'm putting in a record of, say, a certain plant that is growing over a wide area, I again usually give my number to mean just in the immediate vicinity of the photographed individual(s), sometimes to as little as a few metres radius. This can be just as misleading as the alternative approach. You can always record a number and add a comment as to what sort of area you're number relates to. No simple answer, I'm afraid. I'm not sure what distance is used when the system determines "nearby" records, but that might be a more meaningful way to try to determine the approach.

RodDeb wrote:

22 Sep 2020

Thanks Harvey, yep it is a tricky one. I like your suggestion of recording a number (probably in the immediate area) and adding a comment if there were more in additional areas visited on the day. Sometimes even then it is difficult to determine what number to put, but underestimating is probably best. Thank you very much for your time and help I will adjust this record as per your very helpful suggestion and try to remember doing future records a such. No promises though as my memory is really getting pretty bad :). thanks again.

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