But, what right does someone have merely adding text to an image to claim copyright of an image?
The location of the watermark at least, implies the image is yours - I'm certain I've seen the image used by Associated Press, or at least in articles. Although, they could have been from another photographer nearby?
Personally, if I couldn't contact the image owner I'd not use the image. I've done a few 'meme's for anti-poaching and always contact the original image holders for permission. And I'd not place my own copyright mark unless I knew the original licensing for that image and had permission. Just my opinion. I'm hardly a pro-meme creator ;)