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Duck, Duck, Turtle

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BY: MR. PAT SIMMSGEIGER, CLM, DIVERSIFIED WATERSCAPES

I remember my mother refusing to get a turtle for me as a pet. She understood that turtles transmitted salmonella, but she probably had no idea baby turtles also transmitted hepatitis-B. She told me not to touch the ducks in the neighborhood lake. She probably heard they hosted alpha-herpes virus, which caused high mortality rates in ducks, geese and swans. This disease first appeared in Long Island in 1967, transmitted from European flocks. In the last 50 years, these health threats have spread worldwide and normalized in the public mind. There is emerging evidence that turtles, ducks and geese, adapted to the diseases they carry, spread antibioticresistant bacteria. As an aquatic expert, what keeps me awake some nights is the possibility these bacterial strains could transfer their resistance to water algae.

Ducks and turtles are as ubiquitous to water environments as shells on a beach. These water species excrete waste with bacterium, which settles into soil already laced with antibiotic run-off from human activity. This long-term buildup becomes a habitat for new generations of bacteria. In a scientific study of a meat duck farm conducted in 2017, the data indicated that the deeper the excrement layers, and the longer these layers went without removal, the more numerous the antibiotic-resistant bacterial species, plus the greater number of antibiotics to which these species showed resistance. These bacteria also evolved resistance to zinc, copper and cadmium. Copper is the primary element used to control algae and cyanobacteria in water. A Harmful Algal Bloom(HAB) is the result of runaway algae and cyanobacteria growth when heat and nutrient loading are abundant, and eco-diversity is low. HABs can be extremely toxic.

Could algae learn antibiotic and copper resistance from bacteria? Algae are in every environment on the Earth, having emerged as a simpler species about 1.7 billion years ago. Bacteria existed a couple billion years before that. Cyanobacteria preceded these by about 1 billion years, being the first life on this planet. Clearly these species learned or stole abilities from each other, then continued to evolve to the present day. It would be very unlikely that this adaptive behavior has suddenly come to a stop. More likely, these microorganisms are reacting to human activity, feeding on modern waste, adapting to our chemicals, while they continue to compete and learn from one another. Microorganisms comprise the vast majority of biomass, which has always been true and will probably always be true; humans are a recent experiment.

Algae colonies cannot be completely eliminated, only limited in size and reproduction. Not only are there immense varieties of microorganisms adapted to every environment, but each cell has the capability to create a daughter with adapted characteristics. There are about one trillion species of microbes on Earth, and 99.99 % of them have yet to be classified. Clearly, microorganisms have no problem evolving, with the new species consuming abundant nutrients while resisting threats that limited the mother cell.

What is the possibility this new algae strain would move out of its home pond? Birds move from lake to lake, visiting all the water features in their territory. Turtles have a capacity to travel as well. The wind plays a large role in transporting microorganisms over long distances. The entire Earth is covered by microorganisms well-suited to each set of conditions. ‘Survival of the Fittest’ is the rule, so there is every reason to believe that once a species can resist local defenses, it will find a way to spread to every nutrient source available.

For aquatics, copper is the active control ingredient when other measures fail. Although antibiotic resistance is a problem all its own, it is algae’s resistance to copper that presents major concerns. But what can be done; is this inevitable? Human runoff into streams and lakes should be reduced, but this solution is beyond the scope of aquatic managers. Next is the cleaning of muck layers from lakes and ponds. This step is commonly delayed for decades for budget reasons. The last solution is the control of bird and turtle populations, which is socially and politically difficult to carry out.

Reducing animal populations runs into regulatory issues, having nothing to do with The Endangered Species Act of 1973, but rather from public opinion. A complicated permit process is the bane of property managers. Restrictions on turtle, bird and fish removal defeats even a permitted refurbishment plan. A San Francisco property requires humane fish euthanizing, beginning with a gentle capture, then freezing, and finally a chemical soft-wash. After many years they are still looking for a contractor. Most water features in the United States are decades beyond their life-span for refurbishment. This delay in cleaning exacerbates the biologic risks while limiting water health.

Recent events have demonstrated how quickly the status-quo can change. In 1967, Avian Infectious Bronchitis Virus was studied as a crossover vector for human bronchitis, the same year dead flocks were found in Long Island. Today, we may be ignoring signs of a larger problem, where algae could incorporate resistance from bacteria, vectored through birds and turtles which densely populate water features. Even recognizing the signs, our hands remain tied by sentiment for these adorable creatures, many of which we encourage to live in under-served lakes.

Pat Simmsgeiger is the President of DWI, a Certified Lake Management company and manufacturer of aquatic product. He is one of the fewindividuals in the industry that is an expert in all stages of aquatictreatment, from product development and manufacturing to application andtreatment with over 40 years of experience throughout California, theUS, and internationally.

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