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The Plant That Ate Bradford Beach

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It was a warm, muggy September morning. Summer, which had been missing in action, arrived for a while to welcome students back to school. So I decided to check out Bradford beach. I drove down to the parking lot on the lake with my windows up and the air conditioner on. I wasn’t prepared for what happened next, but when I opened the door it hit me, or more correctly, assaulted my nose. The unmistakable smell of rotting organic matter. With school open, there were few people there, just a number gulls and a couple of young women dragging large garbage bags across the sand to a pile near the parking lot. I was looking for evidence on the beach of a disagreeable visitor; this evidence was abundant, and those garbage bags were being loaded with algae. This story is about our great lake, its beach, what is going on in its waters. I had been at a conference on the Great Lakes at UW – Milwaukee in August, and while participating in a discussion on the future of Lake Michigan, it occurred to me that I used to love to swim at its beaches, especially at the end of summer when the water was warmer. For a number of reasons, I had not jumped in the lake for quite a few years. I grew up in Racine, which has a marvelous beach. I used to hang out with friends at the Zoo Beach for a good part of summer in grade school and high school. I remember lake level fluctuations and the dramatic change that occurred on the open sand. Some years the lifeguard stands at the Racine main beach were 20 yards or more away from the water. A year later the water would be lapping at the foot of the stands. One winter the ice went to the horizon, and the lake created a mental picture of an infinite constant. It seemed to go on forever. At the same time, however, this constant was continuously transforming. Over time I learned to look at what seemed to be a static part of my life as an ecosystem undergoing dynamic change, much of which seemed negative. The beaches became assaulted with environmental problems that were discouraging to swimmers. My beloved lake was under attack. I remember the first nuisance that fouled the beaches and made swimming unappealing the alewife, a native of the sea, had arrived in the lake from the St. Lawrence Seaway around 1949 and had grown to extreme numbers by the ’60s. In summer, the alewives come to the warmer water near the shore to spawn, and scientists theorize that a number of factors then cause them to die off in great numbers. Lake Michigan beaches were inundated with large quantities of dead fish that had washed up on the shore and rotted in the summer sun. This was not a pretty sight, and you can imagine the smell. Lake shore cities tried various methods to clean up this mess with limited success. The environmental dilemma even infiltrated the local culture when a local band named themselves the Dead Alewives. Eventually the crisis subsided, and although the alewives are still with us, large die- offs are not as common as they used to be. Maybe the alewives became food for larger game fish like trout and salmon that the Department of Natural Resources has been stocking in the lake. I was going to UWM and taking Botany courses in the late ’60s. I remember the professor giving a lecture on Cladophora, a branching algae common to the lake. I also remember that this plant became a major nuisance in the ’70s as it began to wash up on the beaches in vast quantities to rot. One causal factor was thought to be excess phosphorus, which used to be in most detergents. This fertilizer was causing the algae to “bloom.” During a bloom, algae grow rapidly, then die off and wash to shore, fouling the beaches. Environmentalists lobbied to get phosphorus removed from laundry detergents and other consumer products, eventually succeeding. It seemed the theory about over-fertilization was correct, because the algae blooms became less significant after removal of phosphorus, and the amount of Cladophora on the beaches diminished. Today, however, Cladophora is back on our beaches with a vengeance, and like so many questions involving our lake and water, the answers why are not readily apparent. Over the summer the DNR, the UWM Water Institute and the UW Sea-Grant Institute have been investigating the causes, and hope to find possible management options. Shaili Pfeiffer of the DNR states, Cladophora “is growing everywhere,” on the bottom of the western shore of Lake Michigan in our test area, from Door County to Kenosha. The algae grows on rocks near shore and it grows on zebra mussels, a relatively new invasive species, that are attached to the rocks. Zebra mussels, which are now tremendously abundant in the lake, filter the water as they eat. This makes the lake water clearer, allowing more sun to penetrate to the algae, a major suspected cause of its stimulated growth. It also seems to increase lake bottom area suitable for the algae to grow. Pfeiffer notes that the algae has been regularly recorded this summer growing at depths of 30 to 40 feet. “Water clarity is definitely an issue. The clarity is really good in Lake Michigan now,” she says. Clarity, a seemingly positive quality, is therefore producing a negative result. Pfeiffer hopes to have results on methods that people have tried to minimize the problem by the end of next summer. Phosphorus tests at the 16 test area sites are not indicating unusual levels of this nutrient so far. Fertilization, however, may be a factor, but not by the normal route of phosphorus and nitrogen levels in the open water. Harvey Bootsma of UWM WATER Institute reports on a study by his group on what effect zebra mussels have on the Cladophora attached to their shell. The mussels produce feces and other concentrated waste (or pseudo feces, they spit out packets of stuff they don’t want to eat), and studies have shown positive nutrient levels in algae sections growing closest to the mussels. Bootsma says the algae “biomass is greater in areas with zebra mussels than in areas without zebra mussels. But it is getting hard to find areas without zebra mussels.” These pests therefore may be doubly contributing to the algae problem by both clearing the water and feeding the algae. To make matters worse, when the mussels die and release from the rocks, they take a load of algae with them to the shore. Sewer overflows and beach closings have also been in the news lately, and although it certainly smells like it, there does not seem to be a direct relationship between sewer overflows and the Cladophora problem. The algae are not directly harmful to humans, but may harbor bacteria so one should wash after coming into contact with it. Official beach closings are related to high Coliform test results of water near the beach. Coliform is a bacteria found in human and animal intestines and is an indicator of possible disease causing organisms in the water. My visits to Bradford Beach showed no evidence of any human footprints running across the large beds of Cladophora on the beach. On purely olfactory and aesthetic grounds, when you have to squish through ten feet or more of rotting algae to reach the lake, most visitors seem to favor leaving the beach to the gulls, foregoing a splash in the lake. This is an effective unofficial beach closing for humans, because to kids, young and old, it matters little if the water 20 feet out is clean and clear if you cannot get to it. Rebecca and Cleopatra, the two young women at the beginning of this story, were working with Milwaukee Community Service Corp., a group making an effort to mitigate the Cladaphora problem by hand digging and hauling it away. Their valiant efforts had cleared a 20-foot section of the beach on the morning I visited. East Side State Representative Jon Richards notes that such efforts have cleared the beach of four tons of the smelly stuff which was then hauled away and composted. Richards thanks Metro Milwaukee Sewerage District, Milwaukee County and the MCSC for helping with this effort. Richards calls Cladophora “public enemy number one. It’s a disgusting mess. We need to find a way to clean it up. What we are seeing on the beach is the tip of the iceberg, the mat of algae goes out a half mile into the lake.” He is trying to get more funding for the “local guys at UWM, who are the experts.” I made another visit to the beach on September 25th. Several UWM Sierra club volunteers were there. They had decided to adopt this beach, and were there to pick up trash and do a little water testing. Favorable winds had brought wave action a few days prior, and the beach was swept mostly clean of the unwelcome piles of algae, at least for a while. These near shore currents play a big role in whether your visit will be pleasant, or smelly. Cladophora, a green, branching algae, is thriving in our Great Lake. The question for citizens, scientists and government officials is how to keep it off our beaches.
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