Our pond is small; maybe a 70 foot by 50 foot oval, and only about 5 foot deep in the middle. Located about 100 feet from the house and close to the road, it is very useful for keeping the ducks and geese occupied and more comfortable throughout the year. They seem to love it. They forage in it, clean and preen their feathers in it, both cool off and keep warm in it, and do a whole lot of socializing in it. The water is sometimes a thick brown liquid, although it does contain frogs and minnows. During hot dry summers it shrinks to half its size. Over the last few years, as the number of our ducks and geese have gradually increased, the pressure they put on the pond increased. Periodically closing off the pond for a couple of days at a time has helped, but this summer it wasn’t enough. The long hot dry spell was pretty tough this year. I grew concerned, knowing I needed to keep an eye on the pond’s condition. Too many birds on warm, stagnant water is dangerous.
Cold moving water has the most oxygen and warm stagnant water the least. Bacteria feeding on the bird droppings, consume the remaining oxygen. This anoxic water, when carrying a high fecal load, can quickly lead to the development of dangerous anaerobic bacterial strains. Without oxygen, most benign bacteria die off in large numbers. Bacteria that can exist in low-levels of oxygen replace them, and they are capable of causing diseases in animals- fish and birds especially (people too). High oxygen levels are toxic to these anaerobes. Knowing that the microbial population in the pond was very high, monitoring temperature and oxygen levels would reveal the danger posed. Wanting to head this danger off, we looked for a good aerator online. Turns out there are a lot of options to choose from! Some types shoot up spray fountains with synchronized LED light shows (outdoor speakers to play your soundtrack of choice were optional.). Some can aerate very large ponds and cost a considerable amount. After hesitating on which size would be enough, we had to make our choice.
The long hot dry summer was grinding on. It’s the very busy season for us. One day I noticed the pond was full with seemingly every duck and goose that lives on the farm, swimming, cleaning, fighting for space and making a loud racket. Later in the day I noticed a white duck struggling to walk. Its legs weren’t cooperating. I got the birds off the pond and most seemed fine, except for a couple that were unable to leave the pond. Gathering them up, I closed the gate to the pond and put the sick ducks in an isolation pen. Two ducks didn’t survive and 2 were left with weakened legs. The pond stayed closed until the aerator arrived. luckily over the next couple of days the overall temperature dropped and some rain fell. After a week of being closed off, the pond was full of tadpoles, small frogs and minnows. Their numbers had increased tremendously. Ducks and geese enjoys a good tadpole snack!
Another plus for closing off the pond was that if forced the geese to graze grass in other areas of the farm, like the orchard, which is where they spend much of their time now during the winter. This kind of rotation takes pressure off the pond and allows its other community members to rebound. Managing resources like this small retention pond is an important part of our overall farm management.
Finally the aerator arrives. The 100 feet of extension cord to run the aerator extends from the house to the base of 3 big Osage-hedge trees on the raised southern bank of the pond. The aerator is a small motor that pumps air through a thick rubber house down to the aerator base in the pond. Positioning the aerator base in the pond was a fun stroll through 2 or 3 feet of thick gooey sediment. We plugged it in and away it bubbles. Cautiously we waited a couple of days before letting the birds back in to fully aerate the pond water, the oxygen levels rose quickly, making survival of the dangerous anaerobes not possible, as oxygen is very toxic to them. The pond health was restored very quickly, but the important test remained- letting the birds back in for a swim. The birds were let back in, and they enthusiastically plunged in and really celebrated with vigor. They formed a tight circle around the aerator bubble and dove in repeatedly in turns. Debris kicked up by the aerator floats to the surface and the omnivorous ducks are there to take full advantage. The aerator remains a big hit and the main attraction in the pond.
Besides the value of aeration to the pond water, there is the real benefit of keeping the pond unfrozen and open in the winter. During the recent very cold stretch, the circle of open water did close down dramatically, but a good sized opening remained. Watching the birds sliding around the ice and then dive into the open water can be amusing, especially in the rain. Local songbirds, herons and others also congregate here in some numbers. They could be seen on the edge of the ice getting drinks, and during the rest of the year the pond can be very loud, with all types of birds and insects carrying on there during the day, and various types of frogs and insects blasting out their incredibly .loud choruses all night.
This is a small retention pond, meaning it was made by machinery many years ago to catch surface rainwater runoff for cattle to drink from. The clay and rock semicircular bank is now embedded with some large hedge trees, a few wild persimmons, cedars, and some maple and thorn trees. The pond sits on a raised plateau and is not directly connected to the area’s watershed, which is the Pomme de Terre watershed. The family that built the pond has been gone for decades, and the Amish family before us did not actively use this pond for their cattle or poultry. Now it serves as an important resource for our poultry, and it needs to be actively managed to keep it healthy. This benefits the farm and the local wildlife. Farming needs to be economically sustainable as well as ecologically sustainable. The aerator helps with all of this.