Gaussian blur in PS causing weird lines ?

Lately on some of my BIF shots I've been using gaussian blur in PS to blur the sky to give it a bit smoother feel and make the bird pop a little more.

I have noticed that on some of my shots where I used this more liberally there are faint lines that can be seen on the blue part of the sky.
Is this normal using this tool or am I being too heavy handed with it? Here are a few examples at full rez .

https://www.flickr.com/photos/117211217@N08/25138470434/in/photostream/

https://www.flickr.com/photos/117211217@N08/25128928694/in/photostream/

I think I found my answer.

Eliminating Image Banding in Photoshop | Graphics.com

Banding when applying Gaussian Blur

Interesting discussion about banding at the Luminous landscape forums.

Ignore it; it is a screen artifact only, and does not actually exist in the image, You're seeing a limitation in your monitor's ability to smoothly display color gradients.

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I could only see the problem in the 2nd one.

Don Kuykendall said:

I could only see the problem in the 2nd one.

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It is present in the first one as well but not as pronounced.

Have you tried lens blur,i find its better for some than Gaussian

mikew said:

Have you tried lens blur,i find its better for some than Gaussian

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I have not, but I'll give it a shot.

I use Google's NIK Viveza and select the area and turn down the Structure. It does a great job and I can limit it to whatever area I want. I use it on grass many times to get a softer look.