It is interesting, we had a cold snap with 20 degree nights and chilly days, rain, snow, only saw 1 egg ribbon and it was draped in around a thin group of tall grass/thin rush that was sticking out of the SE side of the pond. There are lots of sticks and only one little clump of this thin rush/tall grass. I have had all the sticks ignored and the ribbons either on the oak leaves in 6" of water or they have put them in my minnow nets and one draped in/around these slender rush spikes.
I get the sense that water temp is important, shallow water seems to be popular at least in my pond (never more than a foot), The South side was first and the rest went on the SE side (with that side not heavily wooded so not as shaded through the day) and they need protection more than they need branches to drape their egg strands over. I think the 'cavity' in the closely spaced branches are popular, but for some reason the cover offered by the hole leading into my minnow net was very popular too.
Loretta, you may want to experiment with with other types of cavities, try very thin spikes/branches sticking straight up like a natural clump of tall grass rather than trees laying horizontally into the deeper water. Didn't you say once your slope going into your pond is 3:1 or steeper? Perhaps they are looking for an area of more gradual slope?
