Much of the sand at Ontario Beach is currently covered in grey and white shells. They’re everywhere; it’s like walking on a carpet of walnuts.
The shells are from dead zebra mussels, an invasive species that first appeared in Lake Ontario in the late 1980’s. (Some are also, more than likely, shells from the similar quagga mussel.)
They aren’t just a Rochester problem; similar piles of shells have washed up on the lake’s beaches in other parts of the state.
Rob Williams, invasive species program coordinator of The Nature Conservancy of Central and Western New York, recalls visiting a beach adjacent to his organization’s El Dorado preserve, which is located near the mouth of the Thousand Islands, and finding a layer of shells at least a foot deep.
The shell carpets should serve as a reminder that the mussels, which can disrupt fragile food webs, are a serious threat to the lake and that people shouldn’t be complacent, Williams says.
Zebra mussels are established in Lake Ontario and several other freshwater systems across the state, but they haven’t made their way into all water bodies. The best way to protect those waters is prevention — a fact that government agencies and environmental agencies have stressed for many years.
For example, boat owners should inspect their vessels and trailers when they pull them out of the water, clean them off, and let them dry for a week or more before using them in a different water body.
Once an invasive species gets established, it’s tough to eliminate them and the focus generally turns to preventing the spread of that species.
This article appears in Jan 25-31, 2017.
Back in the day, before the Zebra Mussels invaded our local lakes, we knew they were coming and thought they were inevitable. Of course, the Zebra Mussels invasion wasnt inevitable when you think about it.
However prolific and numerous, Zebra Mussels cannot fly. These kind of very invasive species, unlike the Asian Carp, dont eventually swim into our lakes; they are brought to our lakes somehow. Probably boat owners who take their boats from one body of water to anotherwithout inspecting and cleaning them.
Humanity is spreading Invasive Species like crazy because we travel around so much. If we take the attitude that Invasive Species are inevitable and we cannot do anything about them, our ecosystemsour lakes, forests, wetlands, and all those organs of our environment that keep us alive and thrivingwill be at risk.
Environmental collapse doesnt have to be inevitable; but it will be if we collectively dont change our attitudes. Soon.
“they are brought to our lakes somehow.” Somehow??????
But what is being “distressed”– the zebra muscles or the entire lake ecosystem? And what is causing the distress — just the zebra muscles?
Alas, it’s not clear from this article…
There are zillions of zebra mussels at times, but their population seems to rise and fall. They have effected the ecosystem because their food source is the microscopic life forms. They have actually helped to clean up the lake. The lake is very clear now, but that leads to the algae problem. Not sure if they have eliminated a food source for the bottom of the food chain, but it doesn’t appear that anything was eating it before.
The source, BTW Frank, is that they come in the bilge of foreign ships. Their population seemed to wain a few years ago but then they came back, so they either ate all the food, or couldn’t adapt. There also are many other foreign species in the lake like the Alewives and goubies. (not sure how to spell).
The shells you see on the beach mean they are dead, BTW.
Just as a clarification, when I said, “Back in the day, before the Zebra Mussels invaded our local lakes, we knew they were coming and thought they were inevitable,” I was referring to some of our Finger Lakes. Yes, the Zebra Mussels came into the Great Lakes by foreign ships. Back in the 1980s, we knew that Honeoye Lake, for example, was probably going to be infested with the Zebra Mussels because of people were boating in the Great Lakes and the Finger Lakes and we worked with the DEC to try and get boaters at the boat launch to clean their boat and trailers.
To the best of my knowledge, the zebra mussels couldn’t have made it to (most/some?) of the Finger Lakes from the Great Lakes because they aren’t connected at their source. We didn’t try very hard, just some signs and literature and some local articles.
One of the reasons why we thought the Zebra Mussels invasion was inevitable was because Honeoye Lake is surrounded by hundreds of private homes, where there was little control over what private homeowners did with their boats. Meaning, you cannot set up check points at every shoreline property owners place to find out where they were boating.
The fear of the Zebra Mussels was that they would clog water intakes, which they did. They filter the water, but in the process they allow light to travel deeper into the water causing more weed growth eventually. The dead shells, of course, are an indication that this invasive species is still alive in great numbers.
Shells spell distress. Too bad the article doesn’t explain the headline.
The shells are a good thing. Those zebra mussels are dead, showing that they aren’t adapting well to our lakes.
Zebra mussels have a lifespan of 3 to 7 years, and a female can produce 1 million eggs each year.
Say there’s an average lifespan of 5 years. If there is a sustained population over time, you’d expect 20% of the mussels to die each year.
Do we assume that the shells on the beach represent the entire population all dying at once, or do we take the more conservative assumption and regard it as 20% of a very large vibrant population in the lake? (Or rather, the small fraction of the dead shells on the lake that are destined to wash up on this particular beach.)
Since there is other evidence that the zebra mussel population is thriving (e.g. improved water clarity, from 6″ to 3′ over the past decade, according to one study), seeing a large number of shells is far more likely to be bad news, not good.