Q & A with Tammy J. Newcomb, Ph.D., Lake Huron Basin Coordinator for the Michigan Department of Natural Resources
By Chris Grubb, National Wildlife Federation
What is unique about Lake Huron compared with the other Great Lakes?Lake Huron is less productive than Lake Michigan, and until recently, more productive than Lake Superior. Productivity is a measure of the lakes nutrient availability that can transfer up a food web and eventually be measured as fish biomass in the lake. Recent findings show that Lake Huron is now more similar to Lake Superior than Lake Michigan in its overall productivity for zooplankton -the tiny organisms used as food by small fish.
How has Lake Huron’s food web historically been characterized? Formerly, Lake Huron had a thriving “pelagic” food web,meaning an open water environment supporting species like bloater chub, lake herring and exotic or invasive species like alewife or smelt. These pelagic fish in turn provided forage for pelagic predators such as lake trout or Chinook salmon. In the mid 1980s, the fish forage base was dominated by smelt. Later in the 1990s, the forage base became dominated by alewife.
How has that been changing and why? The pelagic environment has seemingly become less productive and through a series of events, both alewife and smelt populations became suppressed. There are few alewife found in Lake Huron presently. In spite of the absence of these species, other forage fish do not appear to be filling the vacant niche,leading some experts to believe that a “benthic shunt” is occurring as a result of invasive species such as zebramussels and round gobies in the nearshore areas. This “benthic shunt” hypothesis suggests that nutrients that were formerly available offshore are now entrained (kept) in the nearshore environment.
What do you consider the biggest threats to the Lake Huron ecosystem?Zebra mussels, quagga mussels, round gobies, bloody red shrimp, spiny water flea, asian carp and all the other invasive species that aren’t here yet, but their introduction remains a risk. The Great Lakes research and management communities collectively spend millions of dollars a year investing inmonitoring and collection of Great Lakes data over time to understand the ecosystem for better management and policy decision making. However, this investment is marginalized by new species continuing to enter the environment and shift dynamics in areas such as the food web. In essence, our knowledge becomes “reset” each time an invasive species becomes a significant component in the food web of the Great Lakes.
Is there anything positive occurring in Lake Huron? Yes, there are some tremendous things that are occurring. In the absence of alewives, we are seeing record numbers of sport fish such as young walleye and perch. Lake trout are showing evidence of natural reproduction throughout the lake. Lake Herring, a native forage species that also provides fishing opportunity, also appears to be expanding in its range and abundance throughout Lake Huron.
How long have you been working on Lake Huron and what keeps you coming to work everyday? I’ve worked as the Lake Huron Basin Coordinator for five years and it’s a tremendous privilege to coordinate fisheries management for the World’s fourth largest lake. The Great Lakes Fishery management and aquatic scientific community is an exceptional group of professionals dedicated to protecting and rehabilitating our amazing freshwater resources. The synergy of working with these professionals combined with the stakeholders who are passionate about this resource is what keeps me coming to work every day.
What can people do to protect Lake Huron? I strongly encourage citizens to make known to their state/province and federal legislators what is important to them about the Great Lakes and what they value. Individual letters are meaningful to our elected representatives. Furthermore, support efforts for habitat rehabilitation and aquatic ecosystem management. In Michigan, fisheries managers are supported 100% by license dollars and yet our primary role is protecting the habitat upon which the aquatic community depends. Even if you don’t fish, the purchase of a fishing license is one way to contribute financially to the effort. Finally, figure out which watershed you live in and how you can contribute to efforts to rehabilitate or protect water quality or habitat in your area. All inland efforts eventually benefit the Great Lakes!
Contact Tammy Newcomb, Michigan Department of Natural Resources for more info: (517) 373-3960 or firstname.lastname@example.org