PDA

View Full Version : Backswimmer & diving beetles



Jonathan Ashton
11-24-2014, 12:18 PM
Small aquarium inside a polystyrene light box. Two flash guns, one either side pointing obliquely upwards.
Tripod Canon 1Dx Canon 180mm macro, ISO 100 1/125 sec f16. I made a quick mask of the subject area and applied a little discrete surface blur to the background to disguise the detritus.
Just had to post this I have never seen anything like it! The backswimmer came down to the beetle and stole about 50% of his air bubble and swam off! I saw where he punctured the bubble, then he went silver and disappeared.
Regards set up, this shot was taken in water taken from the surface of the garden pond but it becomes contaminated in no time- in fact as soon as you add anything, so lesson learned I will wash plants etc before adding. I have since put filtered pond water in. Trouble is now I am finding it very difficult to find anything in the pond, I suspect a lot of stuff will have gone down to the depths.
Not exactly a brilliant shot but nevertheless I thought it was interesting.
All C&C welcome.

John Robinson
11-24-2014, 12:55 PM
Thats amazing !
Corixids (boatmen) have the air layer below the body like this one but I,ve never heard of them pinching some from another beetle. Clever little so and so.
Backswimmwers are the bigger upsidy down ones - which can nip !!
Interesting shot
JohnR

Jonathan Ashton
11-24-2014, 03:55 PM
Glad you liked it John, and thanks for putting me right, in my ignorance I thought backswimmer was an American name for boatman... or do you mean that boatmen are just smaller backswimmers, I think I had better do a little reading:w3, not having a few good days with ID's!!

Jerry van Dijk
11-24-2014, 04:22 PM
Very interesting behaviour, John, and something I hadn't hear before. They are amazingly ingenious creatures. Last year I found out that they are agile flyers as well and can fly considerable distances in search of water. We had a big one in the pool of our summer holiday location. Every time we removed it from the pool it was back in no time flying through the air and taking a big plummet back into the water!

John Robinson
11-24-2014, 04:27 PM
John
Yes the Corixids-Water Boatmen swim the right way up. Notonecta the backswimmers are uside down and a lot bigger. There are only a few species of them but dozens of corixids. I oncetaught a class at Flatford Mill field centre and we did capture/ release excercises after marking them with nail varnish.
Cheers
John

Steve Maxson
11-25-2014, 05:09 PM
Yup to the Water Boatman. What a unique image from a behavioral standpoint! This was probably a once in a lifetime shot - too bad the other beetle was in the way, but nothing you could do about that. Good sharpness on your subjects and very cool reflections in the air bubble. The bright area in the lower right is rather distracting - you might try to tone that down. You might also try increasing contrast as the image has a rather foggy look. I wish I had an image like this in my files - but I doubt it's going to happen. :S3:

Jonathan Ashton
11-26-2014, 07:00 AM
Thanks for the feedback, the foggy look is of course due to cloudy water and just possibly I wasn't perpendicular to the glass. I have also notice that sometimes the glass can steam up a bit so I have been using a hair dryer to ensure it was clear. The other thing I have noticed is the variability when converting in DPP4 or in ACR. The contrast slider helps but ACR has a clarity slider and this greatly enhances the underwater detail
Here is a repost incorporating some of your suggestions, it is not the same image as previously (this is 2 frames later) but illustrates the same behaviour.
All C&C welcome.