Margaret Good one of our Florida House Representatives recently released HB 737 a water quality bill based on Multimodal Biological Control. So what is Multimodal Biological Control and how does this impact homeowners?
Imagine you have a new development and a retention pond is dug behind your house, this is intended to store and filter stormwater and provide habitat to animals as a mitigation from environmental damage to the original property. These ponds are commonly known to be filled with invasive plants, nutrients, and algae that in order to look good require extensive herbicide use and maintenance. Herbicides kill the algae and often many of the invertebrates and beneficial plants present as well. The now decaying algae and nutrients then wash out into the bay where inshore nutrient pollution can make Red Tide worse. Not to mention recurring harmful freshwater algae blooms, herbicide resistant algae, lack of usable habitat, poor water quality, increased maintenance costs, poor property values, and numerous other flaws with current herbicide focused management.
So why wouldn’t we put something in these ponds and lakes to eat the algae? Well some people have tried using Tilapia, Plecostomus, and non-sterile Grass Carp to clean ponds but these are non-native species that can have disastrous effects on the ponds such as erosion, poor bass fishing, low water quality, vulnerability to weather and low oxygen, and overpopulation. So what about native species? Well most native species aren’t as effective as these monstrous herbivores and when using a single species they only remove the portion of algae where they live. For example brown bullhead catfish only eat algae on the bottom of a pond not the middle or top because they live, have adapted, and prefer benthic habitat. So what happens if you use a variety of fish, invertebrates, and plants to target algae everywhere it grows in the pond? This has been shown to be more effective than any single biological control as the fish target different areas and compete with one another. You can even extend beyond just controlling algae and target midge flies, floating weeds, and submersed vegetation.
Frequently Asked Questions
Wow this sounds great but if there are so many native species that can do this why aren’t they finding these ponds on their own? Well, roads, houses, and flood control structures do a great job of preventing fish from finding these retention ponds requiring human based stocking.
If it’s so simple why don’t we do it already? Many countries do habitat restoration including the USA! We plant seagrass, oysters, and stock fish in bays and estuaries to improve water quality and fishing. Multimodal Biological Control aims to do what we have been doing for years in other areas but now do it in freshwater where there are dozens of species that are prime candidates for targeted restoration.
So why wouldn’t we do the same habitat restoration for freshwater? In fact we do extensively use mosquitofish to help reduce mosquitos and it infinitely more cost effective and less laborious than pesticides. We can improve fishing, birding, and conservation. At the same time we save money on maintenance and herbicides, while increasing property values and sport fishing. It’s time to use herbicides as a last resort not a first resort, and simply use native species to preemptively tackle the problems growing in our own backyards.
Multimodal Biological Control is meant to be used as a preventative measure to help reduce herbicide and maintenance costs while restoring our lakes and waterways. Every plant, invertebrate, and fish is native to the region being stocked. Every site gets a few herbivores, filter feeders, and detritivores so that should disease or pollution claim one there will still be a functioning ecosystem. It is about using the way ecosystems work to our advantage and letting natural processes run rather than complete chemical control which has let to declining water quality. This is nothing new, it is simply expanding on the existing policies that work to reduce not eliminate the use of herbicides.
Sean Patton is a wetland biologist and environmental consultant serving Sarasota and Manatee counties. He has written and defended an Honors Thesis at New College of Florida, and continues to do independent research to better understand Florida's ecosystems and provide the most specialized consultations possible. He has presented at the Environmental Summit and many other locations on his research; Multimodal Biological Control which is the selective stocking of native organisms to target and control nuisance organisms.