Enlisting earthworms to fight Great Lakes algae

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Cover crops have become a key ally in the Great Lakes region’s war against nutrient-enriched runoff that grows algae in the lakes and its tributaries.

But so have one of soil’s most ancient and mysterious creatures: earthworms.

The dynamics between earthworms and an important layer of soil just beneath the surface is one of nature’s most fascinating out-of-sight, out-of-mind stories of nesting behaviors that make near-shore land more fertile and productive while also providing more passageways for water to seep in. That helps reduce runoff.

To learn more about the beauty of earthworms, I yield to Frank Gibbs, a U.S. Department of Agriculture soil scientist from Findlay, Ohio. I have a hard time believing there are many people more passionate about earthworms.

Don’t let his skinny frame, shoulder-length hair, cowboy hat, handlebar mustache and sunglasses fool you.

Frank Gibbs likes to get dirty. Not many other guys would gladly encourage a group of journalists to join him at the bottom of a trench in the searing heat to examine the intricate

USDA soil scientist Frank Gibbs points to worm passageways in a lump of clay that help plant roots and water penetrate northwest Ohio soil. Image: Tom Henry

pathways that earthworms create in the soil, as he did one day this summer with a group of writers on a Maumee River watershed expedition organized by the Montana-based Institutes for Journalism and Natural Resources. Gibbs talks like he has a symbiotic relationship with night crawlers.

Scientists have long known that worms play an important role in carrying decayed organic matter on the surface down into the soil. That helps enrich it with nutrients.

More is being learned, though, about how worms also aid with no-till farming practices.

As Gibbs explained, plant roots follow earthworms down three feet or more below the surface. That activity also helps water penetrate more deeply. Even with this summer’s drought, undisturbed land where worms are plentiful in northwest Ohio retained a surprising amount of moisture.

One thing a lot of us probably have never considered is just how earthworms don’t like to wander off too far.

They prefer to nest in the same general vicinity, within a matter of feet of their comfort zone.
Yes, earthworms are real homebodies. If they have adequate cover on the surface and enough decayed organic matter to keep them happy, they’ll stay put.

They typically need three to five years to become established. Once that happens, their magic beneath the land’s surface pays dividends. Their work does more than just cover crops alone. The two work in tandem.

In other words, more cover crops and less plowing can lead to more earthworms which greatly enhance soil quality. And, together, the cover crops can keep more water on the land, thereby reducing runoff of phosphorus and other nutrients that cause large algae blooms.

This summer was relatively algae-free, but that is largely attributed to the drought. Several Great Lakes scientists said there was certainly enough heat to produce a third consecutive record-setting algae bloom if this year’s runoff had come close to what it was in 2010 and 2011.

Jeff Reutter, director of Ohio State University’s Stone Laboratory on Gibraltar Island, near Put-in-Bay, said this summer’s lack of algae should reinforce the need to control all sources of runoff, especially that which is produced by agriculture. Runoff from farms and other non-point sources are much harder to control that what comes out of sewage plants or factories.

The Maumee and Sandusky river watersheds in northwest Ohio are two of the Great Lakes region’s most important because of their role as western Lake Erie tributaries.

Reutter said those two rivers, as well as others across Ohio, need at least a two-thirds reduction in runoff to keep large algae blooms from forming in western Lake Erie.

Western Lake Erie is the Great Lakes region’s most algae-prone area because of its warmth, shallowness, and complex interactions with near-shore issues over population and land-use.

No area in the Great Lakes region faces as many dynamic and convergent challenges. What works and doesn’t work in western Lake Erie sets the pace for other parts of the Great Lakes region, especially on efforts to control runoff.

Lots of work lies ahead for agriculture, as well as sewage-treatment plants and other sources of algae-feeding nutrients.

Cover crops and earthworms will only go so far, but they complement more traditional efforts to keep soil on land, such as buffer strips and tree-lined windbreaks.

They won’t likely stop farmers from plowing their fields, but they can help promote conservation tillage and other lighter agricultural practices, as well as more no-till farming.
If embraced more widely, these practices could help farmers avoid regulations that would curtail their use of fertilizers.

Here’s hoping the benefits of cover crops, earthworms, and more selective plowing of fields — ideally years apart – are more than just anecdotes.
In this video Gibbs explains the value of earthworm activity:

This one shows how smoke blown into drainage tiles emerges from earthworm passageways:

33 thoughts on “Enlisting earthworms to fight Great Lakes algae

  1. Pingback: Little Wrigglers, Big Job | ZOO*3700's Blog

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  3. Good, Then please tell the DNR to ok our permits to stock Perch and Walleye, I meet with them Thursday.
    How much value chinook may or may not have is irrelevant. What is relevant Chinook require a special diet, and require the sacrifice of the entire natural ecosystem to exist. Chinook are king in Alaska, here there just another invasive species.

  4. Stock as many perch as you’d like. The salmon will still be there. The mussels won’t be impacted. We’re talking a very small percentage of water that would be used by perch (and a lot of fish and fishermen like to eat perch) vs. a very large percentage used by very prolific mussels. There are good numbers of big perch near the WI/IL border, targeted by many anglers each spring. There are also many more mussels in that area. 225 jobs for Asian carp? Not even comparable to the tens of thousands of jobs directly attributed to chinook salmon. That’s all from me on this thread.

  5. Dear Scoop,
    Coho recovery plan is no good read above quote: “Yellow perch are a real nemesis to salmon of ANY type” chinook was a salmon last I knew. Want it plainer? Find (Research into control methods for invasive yellow Perch)2011. Ok, now Do some people make money off salmon? Yep. Some people are making money off Asian Carp, one guy I met made $300,000 a couple years ago, currently my understanding 225 jobs are connected to asian Carp. So should we just quit trying to get rid of asian carp because of 225 jobs? Does 225 jobs make asian carp a good thing now? Just because some people make money off something, doesn’t automatically make it a good thing. (0 feet came form a Perch study, and people catch Perch 60-70 feet all the time when there. If the Perch reduce the mussels by half even a quarter that’s a good thing. The fact that 50% of salmon are wild spawn, tell us we don’t have enough native predators. According to the Perch task force, Perch switch to eating alewives at 8 inches, since the whole push here is too many predators, forgive me but, Ta Da! The native fish/predators have to be kept at low levels for the chinook fishery to even exist. Is it fun to catch a chinook? Yep! Never said it wasn’t. Is catching a chinook worth intentionally destroying the natural ecosystem to do it? Not one bit! If I’m wrong then you should have no problem with us stocking perch. We have yet to ask for any money, according to you there’s plenty of food “never get rid of the mussels” so why are you against it? Are you one of those that want to plant alewives? If the “balance” plan works it increases are invasive species problem, doesn’t balance anything. More alewives is the plan, isn’t that true? Simple switch to steelhead and browns keeps your big lake fishery, and we could restore the native Biotic-resistance of the lake/ecosystem. Chinook or nothin gets us nothin but invasive species because keeping the chinook is dependant on protecting an invasive species (alewives) Perch, walleyes are not! Pretty simple really.

  6. Except for Asian Carp, I saw one with 60 fry on the Illinois looking really hungry. I cranked the motor on my 13′ semi-V hull and left.

  7. Pingback: BLM Retiree, Wily Earthworms, Languishing Apples, Cleaning Up #1, and a Visit to The Duchess of Jellyfish | The Nooze

  8. Not reading the coho recovery plan because there is none for Lake Michigan. Put a link on here if you have a specific story to point out. Otherwise we’re talking chinooks, the real stars of the fishery most of the year, and it’s far from “billions wasted” … the economic impact of salmon and trout is multi-billions gained for not only port communities, but Great Lakes boat, electronics and tackle sales. Angler surveys have found that Lake Michigan is Wisconsin’s most popular destination lake, and there are more than 15,000 lakes in Wisconsin. Did you know that Wisconsin is second only to Florida in the number of non-resident angler licenses sold, or that a late July salmon tournament on the Kewaunee/Door County Peninsula sells more than 2,700 tickets a year to anglers who come from dozens of states? It’s a world-class salmon fishery. Perch? Sure I love them, but you can catch them inland, too, or in Green Bay and other Great Lakes bays (where salmon also roam, by the way. In fact, they catch far more salmon in Marinette’s annual brown trout derby than trout, and there’s good perch fishing in that area along with good numbers of alewives, bucking the trend in the main lake. Looks like they’re all able to get along fine there. Did I mention the water is far more murky in Green Bay? Hmm … maybe water clarity DOES have a lot to do with all these main lake changes).

    Alewives likely will never recover to ’68 levels, or even mid-80s. The ecosystem has been changed forever by the zebras first, and now the quaqqas. Even with you stretching perch depth to 90 feet (when commercial netters and sport anglers target them in 10-50), they won’t do a thing to lower quaqqas.

    Adult alewife trawls last fall were close to all-time lows. The plan is to balance prey/predator, thus states are cutting chinooks beginning in 2013, to the tune of 50 percent lakewide. Tom, do you realize that 50 percent or more of the salmon in the lake right now are naturally-reproduced?? Naturals, such as every fish in the Betsie River in Michigan.

    Perch are great. They are not, however, saviors of all things invasive. There are plenty of perch in the Mississippi River system, along with smallmouth bass and other predators that would target Asian carp fry. Obviously, they can’t target enough.

  9. Alright, the near shore areas, are where most off the zooplankton is generated, the spawning grounds etc… Perch depth range is 90 feet, about 4 miles out. So we could have a 4 mile deep living barrier, Perch also eat gobies, mud snails, spiny fleas, and controlling the spawning/nursery areas is the only way we can keep the asian carp from taking over the joint.

    Now some facts, The loss of the alewives will NOT crash the ecosystem, it will only crash the Chinook fishery. The ecosystem can only benefit from the loss of the alewives and any other invasive species. Can other fish eat alewives? Sure, but only chinook need alewives to survive, no other fish. The plan is to increase alewives,to be the dominant fish, not balance anything,basically go back to 1968.30 pound chinook. Managing the lake for one fish, sorry.
    The fact that Perch don’t go out in the middle of the lake is irrelevant, they need to take back control of thier part of the system. Perch are both predator and prey. Perch could feed on juvenile asian carp most of thier first year, starting with eggs, they do not grow too fast, fast but not too fast. The alewives with thier tiny mouth, have only 30-60 before Perch and Walleye “grow too big” and they have kept the native fish population down for over 60 years. So it is possible to do.
    Since either you refuse to read it, or can’t handle the facts, Coho Recovery plan is no good “Yellow Perch are a real nemesis to salmon of any type, by consuming thier eggs and fingerlings”
    Perch could be a real nemesis to all invasive species, but that would include the alewife/chinook plan, and we’re back to the save the alewives again. Until that changes, we’re wasting billions of dollars, and leaving the lakes wide open to the Asian Carp, that chinook wont eat, because they only eat alewives

  10. Tom, when we were youg, we used large circular hoop nets to catch eel in the lake close to tributaries. Sometimes we’d pull in a bullhead or two, but we’d throw the eels in a box about 1.5 feet deep then take them home. We quit doing this when wardens started “pulling us over” to see what we were doing with the hoop nets. They never harassed us, but we quit doing it anyway. I wish we hadn’t quit, since from what I understand, hoop nets are a good way to catch asian carp. And asian carp are already here in the form of grass carp. People stock grass carp for the aesthetics they create instead of worrying about their balance in the ecosystem. No one is interested in throwing them in a box and taking them home.

  11. A 6.5-acre inland lake vs. Lake Michigan’s 14-million-plus acres? Sorry you don’t understand Tom. More than a year ago we were told by researchers estimating the biomass that 950 trillion quaqqa mussels line the bottom of Lake Michigan. The vast majority of those, Tom, live at depths perch DON’T and WON’T EVER go. You will NEVER mitigate mussels with perch, even if you stocked 950 trillion perch! Why? Sea Grant fact sheet states: “In the Great Lakes, quagga mussels are commonly found in waters more than 90 feet deep, while zebra mussels are usually found at depths of 50 feet or shallower.” The Michigan DNR website states: “(Yellow perch) are rarely taken from waters more than 30 feet deep.” Commercial netters I know on Green Bay often target 20-40 feet, occasionally as deep as 50 feet. But quaqqa mussels blanket the lake bottom out to 500 feet or more.

    You want science? Check this out: http://www.glerl.noaa.gov/pubs/brochures/dipoflyer/dipo.pdf

    Give kids something to catch? How about panfish and bass, which are abundant in most inland waters.

    New report shows an 11 percent increase in anglers since 2006: http://asafishing.org/newsroom/news-releases/new-survey-shows-angling-and-hunting-participation-numbers-are-up/

    Good news!

  12. You can get any kid HOOKED on fishing, just give them something to catch. Did you even read the Coho recovery plan is no good? Bruce here just told you Perch eat snails, already proven they eat mussels. Lack of predators allows all this. We have predators for all these, but they also eat alewives and baby salmon, so officially we don’t, or it wont work, or they’re too deep blah blah blah….
    “Invasional Meltdown” in which invasion by one exotic species facilitates subsequent invasions by other species. Ecosystems become more easily invaded as the cumulative number of species introductions increases. Invasion and Predation in Aquatic systems, 6/16/2011 Judith Weis. Call her a liar, but since the facts say all this is occuring right now, including an eradication effort of invasive yellow Perch in the pacific northwest, I wouldn’t. I don’t care if we use 5 gallon buckets and only raise 10 2 inch Perch, that’s 10 that wern’t there yesterday, 10 with a better chance to survive, 10 that will live longer eat more invasive species than salmon. And everyone they eat is done spawning. We are supposed to be mitigating the impact of invasive species on the ecosystem. Bt no, we have to mitigate the impact on the salmon stakeholders by increasing an invasive species! Sorry, man blah blah don’t get it.

  13. Good point Joe, but can’t let misinformation go without posting the facts. Some folks might not know any better! Tom, nobody is sacrificing anything for one fish. You want perch? Go to the southern basin of Lake Michigan, Wisconsin or Illinois near the state line, in spring. Big perch! Deeper water than years ago (30-60 feet at times), again likely due to clarity, but still far shallower than mussels can go. Lots of folks fishing for perch down there in boats and on shore. In this changed forever lake (clarity), fish go where they want to go. As for the loss in anglers, certainly some shore anglers have left as the water clarity became an issue (far fewer fish hanging out that shallow any more, and the ones that are may be much tougher to catch outside low-light times). But the bigger picture is that loss of anglers has been nothing more than a sign of today’s “busyness” and “digital world” in which we’re losing anglers, hunters and other outdoor users. A sagging economy hasn’t helped. Gas isn’t cheap! (Neither are iPhones, iPads, Kindles and Internet access and cell phone coverage, but that’s another story). New report shows an 11 percent increase in anglers since 2006: http://asafishing.org/newsroom/news-releases/new-survey-shows-angling-and-hunting-participation-numbers-are-up/. A good site to learn more is http://www.takemefishing.org/. I took more than 50 people fishing for salmon and more than a dozen kids for panfish and bass this past summer, all for free (not a charter). A number of young anglers caught their first fish and are HOOKED. Are you doing everything you can to promote fishing?

  14. Stimulating Conversation! We have a small research lake here in Montana called Fish Fry Lake. It’s 6.5 acres. So far this year we’ve harvested, hook and line, over 4,700 fish, about 85% of which are northern yellow perch. Snails and other periphyton vectoring invertebrates are their primary feed source, although five pronged stickleback and fathead minnows are well represented.. We have a self imposed slot limit, just harvesting one and two year old fish…average weight of 3.7 ounces. Growth rates on the perch are 35% higher than the 95th percentile in a twenty state study tracking wild perch, like these, growth rates.
    The pond also has 6,400 square feet of BioHaven floating islands in place. Zooplankton factories. If you want to cycle nutrients, like phosphorus, quickly into a food web, take a lesson from nature. The wetland effect. That’s what the islands provide on a concentrated basis. Not sure there’s many other options relative to non point nutrient loading/agriculture. A compendium of peer reviewed scientific papers called “Periphyton, Ecology, Exploitation and Management, by M.E. Azim, CABI Publishing, provides detailed background around periphyton, base of the freshwater food chain. Starts off with biofilm, but diatoms figure prominently.

  15. Please find, Coho recovery plan no good. Perhaps you’ll see the problem. As far as Zebra mussels go, they are probably the worst at avoiding predators there is, so it’s just a matter of sufficient numbers of predators to control them. I don’t believe in nothing we can do.

  16. The alewives are responsible for decimating the Perch and walleye. Green bay has just started coming back, as with Saginaw/Huron. The mussels got a big head start. Asian Carp have a 35 year head start, and the best plan the DNR has is to increase alewives? Going public doesn’t change the fact that the DNR is increasing an invasive species, there is no “balance” they need a minimum of 123 pounds of alewives per Chinook to hit 17 pounds in 3 years. This means we sacrifice the entire natural ecosystem for one fish. Google “biotic-resistance” I agree with those experts, principle is the same for all invasive species. You people act like no one will come here without chinook. Fine don’t come, 1/2 million people quit buying fishing license since 1986, agree with you, they don’t want to fish salmon either. 30% drop in license sales last 12 years, right in the middle of the hot salmon fishing. I don’t care if chinook crap silver dollars when they get in the boat. Since being able to chinook fish requires the intentional destruction of the natural ecosystem to exist, it’s value is irrelevant!

  17. What came first, the chicken or the egg? Don’t argue for Tom, argue for 3 or 4 comments. There are brighter streams with fish out here… Maybe you haven’t heard of a clown fish… Scoop, I agree with you whole heartedly, but domoic acid is domoic acid. Ask the seals in California or the sleeping alligators who’ve eaten too many gizzard shad… Urea!! I’ve pestered a common fellow with a “40 IQ point” advantage more than enough, don’t you do the same.

  18. Tom M., Green Bay has a lot of perch and loads of mussels. Once again, you seem to be missing the fact that the lakes have been changed forever. The clarity in the main lakes alone will prevent perch from ever dominating. They are simply easy targets vs. the perch you remember as a youngster, when it would have to be dead calm for days on end just to see bottom off the end of a lakeshore pier! Today you can see bottom in 30 to 40 feet of water from the surface a mile off shore when it’s calm. No comparison. And again, perch don’t go DEEP. Mussels carpet the bottom of the lakes – even in hundreds of feet of water. There are NO perch out there. You will never have perch eat enough gobies or mussels to make a difference. Smallmouth bass love gobies. Walleyes eat ’em too. Even whitefish move in and dine on young gobies. There are still way more gobies than perch and other game fish. Salmon fishing draws tens of thousands of anglers to lakes Michigan and Ontario spring through fall. Without it, many ports would lose one business after another. Huron has many of its natives coming back, but the charter numbers (and some businesses that went down at the same time) have never recovered from the alewife/salmon crash. You want perch and other panfish? Head to inland lakes where the water isn’t so clear; they’re available in good numbers, yet fewer anglers are fishing for them. Why? Changing times. iPads, iPhones, Kindle Fires, the Internet, cable and satellite TV and so much more. Take a Kid Fishin’!

  19. Matt is correct there is a problem in our native forests with Night Crawlers (Lumbricus terrestris). In agricultural fields it is much harder to maintain night crawler populations, and they can be very beneficial. Earthworker earthworms (working the top 12-16in) of soil are easily killed with tillage, cover crops help stabilize the soil and make a better habitat for the earthworms- reduced and better yet No tillage in combination with cover crops is the best solution for building beneficial earthworm populations.

  20. If you read the studies, too many planktivores of any kind increases algae blooms, top down control is best. One study, alewives dumped more phosporus than external sources. If alewives can keep native fish populations knocked down for over 50 years, then Perch can do the same thing,to the mussels with abundant numbers. If Perch can never control them then, we should plant all we can, never run out of food, plus they eat gobies. Perch retain the least amount of PCB of any fish in the great lakes. People want Perch, not so much mussels and goby. Fremont Lake has both zebra mussels and carp (used to be overrun with carp) killed and restocked. You have to look hard to find a zebra mussel, anywhere in the open including shallows where the Perch can see them they get eaten, controlled healthy Perch population. Carp still there (they didn’t kill the upper lake) but very few same predator control. Keeping alewives dominant for one fish (chinook) is ridiculous, but that’s the plan. PS According to the fishery commission report there was a drastic drop in mussels they don’t know why, 2005 biggest Perch spawn ever 8 inch 2008. But 50 per day limit fished down mussels come back.

  21. With more phytopankton in the lakes, you’ll have less nutrients for algae blooms. With more alewives there’ll be less plankton for everyone (even alewives need a balanced diet). I may be wrong, but I think the goal is to try to get humans further away from the bottom of the food chain. When birds start dying from a botulism spread by mussels, you’re happy not to be in the direct line of the bottom of the food chain. When alewives eat the problem, birds don’t die, the problem is on your plate… Something is wrong with the water quality… Better it was the birds than me… or Tom.

  22. Good post Claire. Tom M., you couldn’t put enough perch in the lakes to take care of the mussels, which practically cover the bottom from one end to the other while perch for the most part are relatively shallow water feeders.

  23. Tom M., algae are not all created equal. Cladophora is an attached filamentous algae, therefore not phytoplankton eaten by zooplankton. The HABs in Lak Erie are also not generally consumed by most zooplankters – they’re cyanobacteria. The current status of the Lake Erie with respect to algae blooms has little to do with a decline in control by zooplankton grazing. Nutrient dynamics in the lake has changed emmensly since the invasion of zebra mussels, so older research won’t necessarily apply to the ‘new’ ecosystem.

  24. Scoop,
    Yes they do, but it seems not enough. The natural fishery is coming back in Huron, sans alewife but with mussels. Google alewife+algae, lots of stuff. From what I can find, protecting the lager zooplankton should be our main goal, shortly after alewives got in drastic change in zooplankton and according to Don Scavia Uof M (e-Mail) the 1950’s is when algae blooms started, which coincides with the peak in overfishing, and alewife dominate. According to Need for watershed approaches EPA, link from MDNR website concerning Harmful Algae Blooms. Multiple reasons but included is “Overharvesting of fish, and other organisms, introduction of exotic species.” The larger zooplankton is the buffer/immune system of the lakes sacrificed to the alewives intentionally, because chinook only eat alewives, one fish. Since the facts all jive, where alewives are removed/controlled restoration begins. Mussels can be controlled with predation as well, Perch eat them, but have to be abundant, they also eat alewives, reserved for chinook not allowed in high numbers. You might say Erie has lots of Perch and Walleyes, yep, but by who’s standards, ours or natures?

  25. Earth worms are also invasive and are causing major shifts in plant community dynamics in a forest by breaking down leaf litter too fast. Yet another pressure on our dwindling wildflower populations :(

  26. Wow–who would have thought that a former Lynyrd Skynryd band member would be into earthworms? But, earthworms are from the south…so I guess it makes sense.

  27. I attended a session with Mr. Gibbs, Julie Weatherington Rice and others some years back. At that time it was thought that the worms create migratory paths for pollutants in clay soils.
    Interesting how earthworms keep coming up in discussion on many fronts to help, or is some cases hurt, our waters.

  28. According to a study on Lake Champlain. 4/26/12 Risks associated with lake trout stocking….. Due to alewives wiping out the larger zooplankton. “In general this means that nothing is keeping the phytoplankton in balance” “High importance to keep alewives in check” Since this happens every where alewives go, why is the plan for Lake Michigan to have roughly 250 pounds of alewives PER chinook? (This is the amount that would be required to grow 30 pound salmon in 3 years) Radishes and worms, no till, all good stuff. But no matter how the phosporus gets in, nature control (Large zooplankton) is gone.
    We have to intentionally destroy the natural ecosystem, for one fish.
    Whatever value chinook fishing may or may not have, is irrelevant. To destroy the natural ecosystem, there ain’t that much money!

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