Can you get a closer photo, including the stem?
Do the stems still look okay?
How moist are you keeping them? Soggy soil isn't good for them, nor really dry.
What kind of mulch and soil are they in?
I think you'll have better luck next time if you start them in a container with good potting mix, like Duane suggested. I always start my Salvia seeds in containers. They are just too pricey or difficult to collect for me to take the chance of losing them to the elements and hungry birds.