Read about Kathy Biggs

 A Four-Part Series on Building Ponds for Wildlife

Part 3
Maintaining a Wildlife Pond

by Kathy Biggs, California USA
Click images to enlarge

In Part 1 of this four-part series, the philosophy and mindset for building ponds for wildlife is covered. How to Design the Pond, Part 2 in the series, describes how to design a wildlife pond. Revisit Part 1 | Part 2.
     

Pond Maintenance

Maintaining a wildlife pond differs from maintaining a tropical or koi pond because a wildlife pond doesn’t need to be cared for as fastidiously. Fallen leaves will need to be skimmed off at times and plants will need to be thinned, but the critters that are part of the wildlife cycle that the pond supports are living among the debris and plantings. Therefore, when doing any maintenance, it is important to always check any material removed from the pond for critters! Think of it as a treasure hunt. A dragonfly nymph may be clinging to the underside of a fallen leaf. Or frog eggs may be attached to underwater plant stems. 


Often the best time of day to do pond maintenance is in the early morning hours. At that time of day, the warmest water in your pond will be at a deeper level than at the surface, and critters will have “migrated” there overnight for the warmth.  

Two techniques that work well for protecting pond inhabitants are to (1) always look into your skimming net before removing the contents, and (2) put your skimmed leaves into a bucket or tub of water and place it in the sun. If you’re willing to do both steps, you’ll save more of the pond critters clinging to the plant debris. When you look into the tub later in the day, you’ll find that all the critters will have moved to the sunny side (rather than the shaded side) of the container and can be scooped out and returned to the pond. 

Because you are providing their ideal habitat, native pond plants will flourish in your pond and may need periodic thinning during the summer and fall months. This is another perfect way to spend a hot summer day! If you must enter the pond, use the steps that you’ve provided. I choose to wear tight-fitting bicycling shorts because they prevent any critters from getting inside my clothing! They also are usually made of material that is fast drying. It is best to enter the pond when it is cool and in the shade, as sunblock on your legs or arms would pollute the pond. 

 


In the fall you may need to skim off fallen leaves. If your pond is under or near several large trees, I suggest that you suspend bird netting over the pond to catch the leaves before they hit the surface. A photo in Part 2 of this series shows the pond with netting suspended over it. To prevent birds from getting stuck in the net, be sure to use a single layer and not allow folds to form in the netting. Not all leaves need to be removed as some litter in the bottom of a wildlife pond provides habitat for pond critters.

Winter pond cleaning can be a challenge, but proper apparel makes all the difference. For cold weather, nothing beats fisherman’s waders! Long johns under a wading suit and a warm cap will keep the pond-cleaner comfortable in inclement weather.

When you go into your pond, it’s handy to have a partner nearby so that if you forget anything, or need assistance, you don’t have to leave and reenter the pond. When you enter your pond, you stir things up, and you want to keep this to a minimum. That’s why a “go-fer” helper is a good idea. If I take a tub (or even a garbage can lid) into the pond with me, I can float my tools in it as well as the plant clippings I remove.  

 


Don’t be hasty about throwing your pond clippings onto your compost pile. They may be full of critters! What works well is to put down a screen mesh (1/2” mesh or chicken wire works) over some rocks and water just inside the pond edge. Put your clippings on the screen and gently hose it down. This will help any critters fall back into the pond. Within a half hour everything, except any eggs that were laid inside plant stems (darner dragonflies and damselflies do this), will have had a chance to return to the pond. You can’t save eggs but you’ll save many of the already hatched inhabitants.

It is helpful to know what the underwater critters in your pond look like. Below left is a scan of a skimmer dragonfly nymph. It is squat in appearance and looks like a six-legged spider. A damselfly nymph, below in the middle, is thinner and much smaller than a dragonfly nymph and it has three feathery gills at the end. A darner dragonfly nymph, below right, is long and narrow, and looks like a miniature dragon. A diving beetle nymph has big jaws and a mayfly nymph has feathery gills alongside its abdomen.

     


Skimmer dragonfly nymph


Damselfly nymph


Darner dragonfly nymph

Koi ponds are usually cleaned every winter, but a wildlife pond should only need to be cleaned every third year – if necessary. Some wildlife ponds can go six years or more before they need to be cleaned. Pond cleaning is best done during your pond’s dormant time. For certain, it should not be done in the spring when frog eggs (see photo at the left) are in the pond. If you live where your pond doesn’t freeze over, January and February in the nothern hemisphere or July and August in the southern hemisphere can be good pond cleaning months.
     

When you are ready to clean your pond, you can easily remove the water by turning your pond pump so that it is pumping the water out of your pond instead of recirculating it. If you’re not using a recirculating pump, you can siphon off the water. Depending on where you live, this water can flow into your yard or be shunted off towards a drain, but at least some of the pond water should be collected for reuse in the pond.

Try to preserve as many of the critters that live in the debris at the bottom of the pond as you can. Here’s a good technique: Pump or siphon the water into a holding tank. A child’s wading pool makes a good holding area. 


The pump can remove the water from your pond to a level that is only several inches (1"=2.5cm) of water above the muck. After that you’ll need either to siphon it off and/or use buckets. Then you can hose down the sides, pick out debris, and remove accumulated muck with a bucket. Be certain to look for squirming critters such as beetle and dragonfly nymph and put them in the holding tank.

If there are native fish in your pond, stop pumping the water from the pond when there are only a couple of inches of clear water left and remove the fish before taking the pond completely down to muck only. 

Chlorine removal:

If your water is chlorinated, refilling your pond can be a challenge. A large volume of chlorinated water at once could harm aquatic life and plants. Before refilling your pond, be sure to leave the water in uncovered containers overnight to allow the chlorine to dissipate. Some city water contains a form of chlorine that doesn’t dissipate overnight, and you may need to consult your local tropical fish store or pond and garden shop for ways to remove it.

When you refill your pond, remember to add any pond water you’ve saved; it contains beneficial microorganisms that inoculate the newly cleaned pond.

Conclusion:

Maintaining a wildlife pond demands that you pay attention to the critters that live in it. Because of this, the least disturbance possible is usually best. Maintenance differs so much from pond to pond; you may not need to clean summer, fall, and winter. Some wildlife pond owners do heavy maintenance less often – they skim off some leaves every other week or so, but clip out excess plants only once or twice a year. If your pond is built to the size recommended in part 2 of this series (not wider than you can reach into with a net), you can avoid entering and stirring up the pond.



Click here to learn more about Bigsnest Wildlife Pond, 15 years old in 2010 and Dragonfly Roost Pond, five years old in 2010.

Part 1: Why Build a Pond for Wildlife? (WGI Online Journal, November 2009)
Part 2: How to Design a Pond for Wildlife (WGI Online Journal, February 2010
Part 4: Tie in with the Rest of Your Yard (WGI Online Journal, August 2010


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