A couple of good snapshots for size and forgotten there. I don't mean for the deliberate use of that word to be in any way a criticism, just as they stand they come across to me as a viewer as "nice snap, well taken" rather than "wow, look at that".
I think in the circumstances, you've done well with both, but a couple of thoughts about what could be tweaked...
Size: I'd ask what the story/image is here... I don't mean a detailed backstory, but what are you trying to convey? That they are the same size or one is larger than the other? Or that both are very large? For me, this image would work better with a clearer sense of scale - either against one another, which would require the larger one to be closer to camera to get perspective working for you - or against their food, which is cut into large chunks (no control over that presumably!) and therefore doesn't really show how big these things are. The other option would be a closer crop of the nearest as it has interesting, almost "human" looking hands rather than mousey paws and getting closer in to that, its face and its food might yield a more "wow" shot...
I think you've gone and found some really interesting subjects there, but to make the shot stand out I think your subject matter is worth you trying to imagine what the viewer might think as they look at the shot and aim for something other than "cute animals"... all meant in a very constructive way and I hope you take it that way!
Forgotten: no envy for you tackling those lighting conditions. There's some interesting light coming in from what looks like the top and a white balance correction to remove a bit of the golden glow (but not all) may help pick other shades out a touch? I also think it would be one for a very shallow depth of field - partly to allow more light into the camera and partly so you can focus just on a narrow strip of the shells and use DOF fall-off to add extra interest to the image. I also wonder if getting right up against the "corner" of the floor and wall might allow you to use that curve as a leading line? Even putting your camera on live view and placing it into the corner, using the LCD to compose the shot? An interest subject that just needs a bit of contrast (not in terms of light levels, more "differences" in general) across the frame?
In both cases you've done the hard work of finding interesting subjects, so your photographic eye is definitely working well!!