There a couple of reasons that one cygnet might be gray and one white. The runt (youngest smallest cygnet) has not yet turned white, but will in the very near future.

Second, there is a color variation between Mute Swans. Although, Mute Swans are scientifically known only as Mute Swans, many swan keepers designate them as Royal Mutes or Polish Mutes.

Mute Swans known as "Royals", are the tradition color with the cygnets being taupe/grey in color at hatching with black legs and feet. As adults they have reddish orange bills.

Mute Swans known as "Polish" are a leucistic (genetic) coloration that began centuries ago when someone in Eastern Europe tried to produce an albino Mute Swan by interbreeding the swans. This did not work, but what they got was a leucistic coloration in which the cygnets are white at hatching, have taupe/grey feet which continue the coloration into adulthood. The adult also have orange (duller) colored bills.

Now, a caution about feeding the swans in your area. Michigan DNR officials have a plan to kill all Mute Swans by 2030. The officials are trying to introduce the larger Trumpeter Swans for Trophy Waterfowl hunting purposes. The officials and their volunteers along with federal wildlife officials misrepresent the Mute Swans as aggressive, non-native, invasive and other poor attributes to get taxpayers to buy into the killing programs. They will sneak into the nests at night, decapitate the adults and stomp the cygnets to death so that the taxpayer does not know how they were killed, no gunshots or other attention getting killing methods. This has been occurring since the late 90's at taxpayer expense. The introduction of the Trumpeter Swans has also been conducted at taxpayer expense and the wildlife officials have admitted that the price is hefty and that is not a sustainable program even after all of the money has been wasted.

Additionally, the true fact about the Mute Swans that officials are ignoring is that Mute Swans are a Sentinel species which alert to problems in the habitat such as the presence of heavy metals (lead, copper, mercury) and harmful microorganisms. Had the Michigan DNR not been so adamant about killing the Mute Swans for future trophy hunting revenue, the swans may have indicated to the problems in the Flint River prior to the poisoning and deaths attributed to the water. So, again be careful that the Michigan DNR does not find out about your family of swans or they may disappear in the night. The Regal Swan