|Two ducks in still water|
When I saw a pair of ducks in the lake, I thought I knew what they were.
“Mallards,” I said to myself reflecting upon childhood memories.
When I was young, I often saw mallards swimming in the lake next to my Pennsylvania home. Male mallards have bright green iridescent plumage on their heads and necks in contrast to the plainer – some might say drab-colored females.
Each of the two ducks I saw swimming in my Florida lake resembled female mallards. Both were dappled shades of brown and tan, although one of the ducks seemed slightly darker and its bill was a bit more brightly colored.
|The two ducks look alike|
I considered the possibility that both birds were females but the way they were acting – one bird standing guard while the other bobbed for food – as well as the guard’s darker plumage and yellower bill, made me question their identity.
I was right to be doubtful.
It turns out the two birds were not mallards but a closely related species called Florida mottled duck that lives year-round (non-migratory) in Florida’s freshwater and brackish marshes. Like the mallard, it’s a ‘dabbling duck,’ because it trawls along shallow water skimming aquatic plants off the surface instead of diving for food and disappearing completely underwater as other ducks do. Periodically, the mottled duck bobs under, submerging just its head and neck to feed.
|While one watches, the other duck submerges its head underwater in search of food|
About 40 percent of the mottled duck’s diet consists of snails, insects, small fish and other aquatic animals. The rest of its food comes from the roots and stems of plants, seeds, reeds and even berries.
Mottled ducks aren’t ‘regulars’ on our lake like the heron, great egret, tricolored heron or ibises, but for the past week or so I’ve noticed them while rowing. They tend to swim close to the shoreline and do their best to stay as far away from me as possible. If my rowboat passes too close, they take flight.
It could be that I’m seeing them lately because they’re ready to have babies. Mottled ducks nest February through July in stands of tall rushes, reeds or palmettos close to shallow water lakes. They select a site close to a lake, hollow out a space amidst the dense vegetation then line it with soft down. The female lays 8 to 10 eggs that she incubates for just under a month. A day or two after the eggs hatch, the entire family leaves land and takes to the water where the parents show their offspring how to skim the surface for food and how to “duck” their heads underwater to find aquatic edibles.
I’m not surprised I initially misidentified them. The two species look so much alike, even mottled ducks get confused. Interspecies mating (hybridizing) between mallards and Florida mottled ducks has happened so often in recent years, pure-breed Florida mottled duck populations are in decline. The resulting offspring of hybridized pairs are fertile, which perpetuates the problem.
|Both sexes of mottled duck look similar to female mallards but not at all like the brightly colored male mallard (picture credit: http://www.adventuresofscatman.com)|
Mottled ducks and mallards haven’t always interbred. In the past, they didn’t crossbreed because mallards that migrated to Florida in the winter flew back north prior to mottled duck mating season. That changed when more and more Floridians began raising mallards and releasing them in local waterways.
|Feeding wild ducks contributes to changes in migration patterns (photo credit: http://www.thewoodlandseventblog.com)|
Instead of returning to northern climes, domesticated mallards stayed in Florida year round and bred with local populations of native mottled ducks. In Florida, the release of mallards is illegal but people still do it and interbreeding continues.
I had no idea when I spotted two rather ordinary looking ducks swimming in our lake I was gazing upon critters whose amorous activities can contribute to the extinction of an entire species.
That’s a hefty price to pay for a little wild(life) sex.