The larger contour image seems to have two sources, one of which also feeds the smaller contour.
This is near the heart of a very rich cluster, at z ~0.315. The 'seagull' is, I think, a very wide-angle tail, a #wat; the outer (isolated) radio sources part of the same system. The source - the AGN responsible for the radio sources - is very likely (in) SDSS J162309.28+142149.4, whose SDSS spectrum looks very 'dead and red' (i.e. no ongoing star formation).
Here's the SDSS field, centered on SDSS J162309.28+142149.4, with a scale similar to that of the RGZ image (there are also rather a lot of foreground stars):