Pennsylvania ducks benefit from housing assistance
Though it’s only February, spring sunshine isn’t all that far away, which means migrating duck species will begin returning to the area and pairing up for courtship and mating throughout the coming weeks.
Pennsylvania’s agricultural hub offers an abundance of feed and open waterways for this “re-burgeoning of the flock,” so mallards and wood ducks will most assuredly take up temporary residency in the prime habitat our area has to offer.
According to Pennsylvania Game Commission Wildlife Notes, mallards — the most common of Pennsylvania puddle ducks — prefer to nest within 100 yards of water, on the ground in a depression lined with vegetation and soft down. Hens conceal their nest with tall grass, dead reeds and leaves, and will lay one egg per day until they have a full clutch of 8 to 12 eggs. At that point, incubation will occur and last for 23 to 29 days.
During this process, the hen and her eggs face a host of challenges, including predation from skunks, crows, raccoons, opossums, and even the threat of accidental nest destruction by motorized equipment.
In areas protected from intrusion, mallards can benefit from man-made nesting structures known as mallard tubes, which can be a fun winter project to make from a roll of wire fencing for shape, rubber roofing for weather-proofing, and loose straw for cushion and insulation.
These tubes can be placed a few feet above the high waterline, and they will often be utilized by breeding pairs if surrounding habitat is appropriate.
Our second most common species in this area is the wood duck, although they seem to be more finicky and reclusive than mallards.
As their name implies, wood ducks are closely associated with habitats containing wooded areas near water. Ideally, the trees in those wooded areas should be big enough to have developed cavities of suitable size for wood ducks to nest in. When natural nesting cavities are lacking, manmade nest boxes can substitute for the lack of cavities.
According to Lancaster-based Ducks Unlimited biologist, Jim Feaga, wood ducks are one of several duck species that nest in tree cavities. Bufflehead, hooded merganser, and common goldeneye also nest in tree cavities and can benefit from nest boxes.
“In Pennsylvania, wood ducks and hooded mergansers are the primary beneficiaries of duck boxes,” Feaga explained. “Nest boxes were first erected for wood ducks in Illinois in the late 1930s. Since then, many designs and modifications to nest boxes have taught biologists what works best for wood ducks.”
Feaga recommended placing boxes in obscure places on trees well within the woods. Boxes that are in plain sight (on poles in the middle of a wetland) often are invaded by many wood ducks and used as dump nests. These boxes rarely have good hatch success because the female cannot incubate all the eggs and most will go addle, or rotten.
“Make sure to put the box up somewhere it is easy to maintain,” Feaga said. “You will need to monitor boxes for the first weeks to make sure starlings or wasps have not taken them over. Do not over-visit once wood ducks begin using or the hen may abandon the nest. There is no set distance that two boxes should be from one another; however, it is a good idea to place boxes in locations that are visually isolated from each other.”
Feaga said a good wetland site for woodies should have three characteristics.
First, approximately half the wetland should be open water, with the remainder in green plant cover. Second, a supply of animal foods, such as insects and other invertebrates, needs to be present (critical for ducklings less than four weeks old). And lastly, water must remain until the ducklings are able to fly at around eight to ten weeks old.
“Don’t be disappointed if ducks do not use your nest box the first year,” Feaga said. “It may take a year or two for them to do so. If the box still has not been used after two or three years, try moving it to another location.”
“But remember, once you put a box out, you have made a commitment to maintain it annually. If you fail to do this, you will have just wasted your time and done nothing for the cavity-nesters in your area,”