Spider nursery

I noticed some strange goings on today around the edge of my pond, but every time I went anywhere near they all disappeared. So I began to crept up very slowly and watch from a distance, what I saw was lots of spiders carrying a sac of spider eggs behind them sunbathing , presumably to warm the eggs up. This is just a small part of them including the close up, eventually they got used to me being there and didn't run off. Fascinating to watch.