My 2 yr old Barred Rock rooster had almost 2 inch long spurs at the start of winter. Every few weeks now I see they look a bit shorter. Sometimes they are black on the end like dried blood, other times they are the same color as his legs. His comb and wattles are fine, as are his toes, so I don't think it can be due to the cold. He is going up/down a different ladder into the winter-time run than during the summer. It's a wooden ladder with 1 inch dowels pretty close together that none of them seem to have trouble using, but it's the only difference I can think of. Any thoughts? Is the spur breaking off part of a natural process?