I am so happy to see these amazing insects back in the garden. We have at least two species, the most noticeable difference is the size. The one in the picture is the bigger one. When the sun is setting and the garden gets slightly shady, you can just stand there and watch them hover in the air. It is quite amazing to see them.
Being very important pollinators and also on decline, I am glad that they are here again. Last year there were some larvae in our barrel of nettle fertiliser and I am hoping that this year we will see some as well (no success so far though).