February 5th, 2015 by iisg_superadmin
Fisheries managers have long known that the population of rainbow smelt in the Great Lakes is on the decline. Once so abundant that they could be fished out with a pot or strainer, this important prey fish survives today in numbers hovering near historic lows. Numerous causes for the falling population have been proposed, but new research suggests that the population patterns and the forces driving them are more complicated than previously believed.
The 2014 study reveals that number of smelt that survive their first few months has actually been on the rise since 2000. But this increase in hatchlings isn’t translating into more adults, and it is unclear when and why that breakdown is happening. Whatever the cause, the loss of adult rainbow smelt is enough keep the population trending down even as offspring survival improves.
Researchers from USGS, IISG, Purdue University, and the U.S. EPA Great Lakes National Program Office, discovered the unexpected increase in offspring after analyzing roughly 40 years of fisheries data using a novel modeling technique.
Fish populations are typically analyzed using a statistical model that that assumes the relationships between different variables—things like number of offspring, number of adults, degree of predatory pressure, and amount of rainfall—remain the same over time. For this study, researchers used statistical tools rarely used by fishery scientists that better reflect the ever-changing nature of the Great Lakes and make it possible to detect more subtle population patterns.
Perhaps most surprising is that offspring survival is on the rise in Lake Michigan despite the fact that their parents are up to 70 mm shorter now than they were in the 1970s.
“We were expecting to see a decrease in productivity because the adults are maturing at smaller sizes, which should mean fewer eggs and less healthy hatchlings,” said Zach Feiner, a PhD student at Purdue University and lead author of the study. “This raises a lot of questions about how well we understand rainbow smelt fisheries.”
Researchers speculate that the drop in the number of adult smelt may actually be allowing hatchlings to thrive. Adult rainbow smelt frequently supplement their diet of zooplankton by dining on their offspring. Fewer adults means fewer predators for juvenile smelt. The need to find food in a lake infested with millions of quagga and zebra mussels that filter out plankton may also be driving adults further out into the lake and away from spawning grounds.
***Photo courtesy of Crystal Lake Mixing Project.
January 27th, 2015 by iisg_superadmin
Managing aquatic invasive species is no easy—or cheap—task. Plants and animals spread to new regions through a variety of routes, many of which involve human activities like fishing, boating, and gardening. Coupled with the fact that there are hundreds of new species poised to thrive in Midwestern environments, it is very difficult for natural resource managers to get a jump on these invaders.
But all that may be changing in Illinois due to a new database cataloging the presence of non-native species across the state. Created at Loyola University Chicago by then-graduate student Abigail Jacobs and ecologist Reuben Keller, the database brings together animal and plant sightings collected by the U.S. Geological Survey, Field Museum, Illinois Natural History Survey, and many other organizations and researchers. Its more than 20,000 records makes it one of the most comprehensive AIS databases in country.
The size and detail of the database reveals previously-unknown patterns in the movement of invasive species that will help natural resource managers better focus their control and monitoring efforts.
“We now have maps showing the number of AIS in each county and showing where species tend to be first recorded,” said Keller. “These are really useful for determining where managers should focus on controlling existing invaders and where efforts should go into monitoring for new invaders.”
These maps and other analysis results are expected to be included in the updated Illinois State Comprehensive Management Plan for Aquatic Nuisance Species. First written in 1999, in part by IISG’s Pat Charlebois, the plan identifies invasive species that pose the greatest threat to the state and provides guidance for organizations working to halt their spread.
“The database will make it easier to connect with audiences by talking about how the specific waterways and habitats they care about are being affected by invasive species,” said Pat.
***Photo: Purple loosestrife is one of many invasive plants cataloged in the database.
October 16th, 2014 by iisg_superadmin
Even before zebra and quagga mussels arrived in the Great Lakes in the 1980s, the future looked a little bleak for native mussels. The invaders came close to wiping them out entirely. But small populations in Lake Erie appear to not only be surviving the invasion, but thriving.
Average density of native mussels before the arrival of zebra mussels was two per square meter in Lake St. Clair. By 1990, zebra mussel density was at 1,600 per square meter.
“By 1992, native mussel populations are almost gone from the southeastern portion of the lake and declining rapidly in the northwestern portion of the lake,” said [Dave] Zanatta, [a biologist at Central Michigan University].
By 1994, there were almost no native mussels left in the lake, with zebra now at 3,000+ per square meter.
“But there was reason for hope,” said Zanatta. “Remnant populations of native mussels were beginning to be found in coastal wetlands in western Lake Erie in the late 1990s.”
More recent research funded through the Great Lakes Restoration Initiative also reveals that native mussels have maintained genetic diversity, a key to any species’ long-term survival.
Again from The Voice:
Zanatta’s research adds further evidence that progress continues to be made on one of the impairments of the St. Clair River – the degradation of fish and wildlife habitat – that led to its classification as an environmental Area of Concern in 1985.
His work also sheds light on the complex ecological impacts of invasive species generally.
With some environmental observers predicting a doomsday scenario for native game fish if Asian carp are able to establish themselves in the Great Lakes, for example, Zanatta’s mussel research suggests that the outlook for native fish might be significantly more positive than forecasts suggest.
To read the full article, click on the link above.
**Photo of zebra mussels courtesy of Michigan Sea Grant.
October 8th, 2014 by iisg_superadmin
Today we take a break from discussing the latest Great Lakes research to recognize one of the scientists who laid the foundation for modern water science.
From the U.S. Geological Survey’s Science Features:
Luna B. Leopold, son of famed conservationist Aldo Leopold, arrived at the USGS in 1950. For the next two decades, Leopold revolutionized hydrologic sciences within and outside the USGS. He is best known for his work in the field of geomorphology, the study of land features and the processes that create and change them. His work is often cited today by leading scientists in water research, both at the USGS and around the world.
Leopold had a lasting impact on the field of water science. He knew the broader importance of our water resources and that humans can have great impact on whether water is available, now and in the future. Our society depends on safe and reliable water supplies, as do the Earth’s diverse and valuable ecosystems. Today, our nation is faced with the challenge of balancing a finite freshwater supply between competing needs, such as agriculture, drinking water, energy production, and ecosystems.
Leopold recognized the fundamental value of science in making smart decisions about water resources and laid the groundwork for modern water science. During his tenure he transformed USGS water research into a professionally-recognized provider of water quality and availability information.
For six years, he served as a hydraulic engineer before becoming the first Chief Hydrologist in the history of the USGS, a position he held until 1966 when he stepped down to pursue his research. While at the USGS, he led the effort to restructure the water science programs to focus on viewing water as a single resource. For example, USGS continues to research the interactions between surface water and groundwater, because use of either of these resources affects the quantity and quality of the other.
***Leopold writes down his reflections during a 1966 research expedition in Idaho. Photo courtesy of USGS.
October 7th, 2014 by iisg_superadmin
Scientists from Central Michigan University’s Institute for Great Lakes Research (IGLR) are expanding their basin-wide Great Lakes coastal wetlands monitoring program with help from grant funding from the U.S. Fish and Wildlife Service and the Wisconsin and Illinois-Indiana Sea Grant programs. The program is one part of a collaborative project that brings together researchers from IGLR, Notre Dame, and the University of Wisconsin-Green Bay. The results will help natural resource managers better target protection and restoration efforts.
From the Midland Daily News:
They also will be able to help assess the importance of coastal wetlands as they relate to the food web of the Great Lakes ecosystem by studying otoliths, or fish ear bones, to determine where fish are obtaining energy for growth.
Otoliths grow daily, similar to rings found in the trunk of a tree. With the use of a precise laser beam, IGLR researchers can sample the chemical composition of targeted areas of the otoliths and relate this “chemical fingerprint” to specific coastal wetlands, even when fish are caught in the open water of the Great Lakes, far from any wetlands.
It is hoped that this research will result in a long-term, sustainable monitoring program aimed at restoring and protecting Great Lakes coastal wetlands, which provide a critical habitat for many species of birds, mammals, reptiles and amphibians, and an essential spawning and nursery habitat for many fish species of ecological and economical importance to Michigan’s $7.5 billion commercial and sports fishing industry.
The research project is one of three awarded a combined total of $380,000 from IISG earlier this year. Additional projects seek to uncover the connections between sediment removal projects and a community’s ability to weather environmental hazards and identify why people adopt stormwater management practices.
And IISG continues to fund strong research projects like these. In fact, last month we announced a new funding opportunity for research addressing key economic planning questions facing the Great Lakes region. Researchers may request up to $96,000 for 18 months. Proposals are due by 5 pm CST on Nov. 17, 2014. Read the full RFP for information on project and application requirements.
September 2nd, 2014 by iisg_superadmin
Researchers at the Chicago Botanic Garden are asking wetland managers across the country to join PhragNet, a collaborative network that brings scientists and managers together to improve Phragmites control strategies. From the latest issue of IISG’s The Helm:
The idea behind PhragNet is simple. Managers provide soil and plant samples and share information about their management strategies and goals. In return, researchers use that data to better understand Phragmites invasions and help managers hone in on the most effective control and restoration strategies.
The IISG-funded network is still in its early stages, but PhragNet co-founders Dan Larkin, Jeremie Fant, Vicky Hunt, and others have already collected data from roughly 50 participants in 15 states and Ontario.
“There is so much we can learn by ‘crowd-sourcing’ information about how to effectively manage Phragmites-impacted wetlands,” said Larkin. “The value will increase over time as we see how sites respond to management.”
For more information on how to join, visit the Great Lakes Phragmites Collaborative’s PhragNet page.
July 10th, 2014 by iisg_superadmin
It’s day four of the Shipboard and Shoreline Science Workshop, and teachers from across the Great Lakes region are hard at work conducting field experiments alongside researchers aboard the EPA R/V Lake Guardian. The group was in Lake Erie’s Presque Isle Bay yesterday collecting water samples and hunting for invasive species. Their work, along with some of the researchers and participants, was featured on WICU 12 Erie.
“I’m going to bring this back to my classroom,” Chad Solomon, a teacher at Chicago’s Whitney M. Young Magnet High School told WICU. “We live in Chicago, but very rarely do kids actually get to the lake. I am going to be bringing this experience back to them.”
Joining the teachers at this shoreline stop and throughout the research cruise is IISG’s Kristin TePas. Kristin coordinates the annual teacher workshop, held each year on a different lake, for the Center for Great Lakes Literacy and the EPA Great Lakes National Program Office.
Sea Grant-funded researchers Sam Mason and Steve Mauro were also on board sampling for emerging pollutants like plastic and pharmaceuticals. You can learn more about Mason’s research in Lake Erie and across the Great Lakes in the latest issue of UpClose. And watch for the next edition later this month to hear from Mauro directly about his work on the Lake Guardian.
*Photo taken during the 2010 cruise on Lake Michigan
June 6th, 2014 by iisg_superadmin
The Michigan City buoy returned to the nearshore waters of Lake Michigan on June 5—this time with an upgrade that boaters, anglers, and researchers have been eagerly awaiting. In addition to broadcasting real-time data on wave height and direction, wind speed, and air and surface water temperatures, the improved buoy now relays water temperatures at different depths.
The sensor chain, which measures water temperatures approximately every 3 ft. from the surface to the bottom of the lake, will help kayakers know when the water is warm enough to paddle out and make it easier for anglers to find and catch their favorite fish. A more comprehensive picture of nearshore water temperatures is also vital for research on fisheries and nearshore hydrodynamics.
“We’ve been getting a lot of positive feedback asking us when the buoy will be in the water again,” said Carolyn Foley, IISG assistant research coordinator. “And they’re all excited to hear that we’ve added a temperature chain to our setup. The nearest buoy with a similar chain is about 30 miles away.”
Real-time data will be available on IISG’s website until the buoy is pulled out for the winter in mid-October. The site currently shows snapshots of lake conditions—updated every 10 minutes—as well as trends over 24-hour and 5-day periods. Buoy-watchers can also download raw historical data at NOAA’s National Data Buoy Center.
Later this summer, IISG will be hosting a workshop designed to help educators develop science, math, and stewardship projects using the real-time buoy data. The workshop is scheduled for August 6 at Purdue University North Central.
May 21st, 2014 by iisg_superadmin
It has been nearly one year since IISG set sail on Lake Michigan to sample for plastic pollution. Since then, Sam Mason, a chemist from State University of New York Fredonia, and her research team have been hard at work analyzing those water samples. The initial results are revealed in the latest edition of IISG’s interview series UpClose.
In this issue, Mason talks about her ongoing work to quantify plastic pollution in the Great Lakes for the first time. In addition to the Lake Michigan results, Mason discusses plastic levels in the other four lakes, explains how plastics could impact aquatic wildlife, and suggests additional research needed to understand this emerging contaminant.
This is the sixth edition of UpClose, which takes readers behind the scenes of the latest research on pharmaceuticals and personal care products. Each interview targets a different component of PPCP research—everything from what happens to pharmaceuticals when water is treated to what bacterial resistance could mean for other aquatic wildlife living in urban rivers. Readers also get an insider’s view of the complex, and sometimes tricky, process of conducting field studies, and the potential implications of research on industries and regulations.
Read previous issues of UpClose at unwantedmeds.org. For print copies, contact Pollution Prevention Program Specialist Laura Kammin.
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