I am always wary about adding titles to a picture, particularly if they do not quite fit the bill.
You might see this as tranquility, but beneath the water that duck is probably kicking hard to move away from the camera (the concentric circles off the duck imply some movement) and the ripples on the pond suggest other movement, likely from the wind. On the whole it is a nice enough portrait of the duck but I am not hearing tranquil.
One thing that is always worth remembering in photography, is the light is often key to creating a good image. In this photograph the light was made during the middle of the day, and it has a bland feel. As a suggestion, go to this same location in early morning and chances are you will discover a totally different scene. Chances are there will be no wind to unsettle the water, the ducks might be still, and the light might create a totally different look to an otherwise grey/green pond.
As another option though, convert this image to black and white for the sake of emphasising the concentric circles about the duck. Do not, I repeat, do not add cross hairs to the circles!
This seems like a nice location for making photos, so keep exploring the idea.