Huron-Erie Corridor Initiative

Research Themes of the HEC Initiative

The broad interrelated biological management-driven research themes of the HEC Initiative include:

1. Restoration ecology of native species and their habitats
Lake Sturgeon Restoration in the Detroit River
2. Effects of aquatic invasive species on native aquatic species
3. Conservation biology of native species

1) Restoration ecology of native species and their habitats,
Sixteen species of fish classified as threatened or endangered inhabit the HEC. Habitat loss and alteration of habitat are major factors that have contributed to the decline of many of these species. Native fish populations have been greatly affected by habitat alterations in the HEC. Millions of tons of cobble and gravel were removed from the St. Clair and Detroit Rivers to build the cities of Detroit and Windsor and create navigation channels (Larson 1981). These gravel substrates provide spawning and nursery habitat for walleye, lake sturgeon, darters, and other native fish species. Substrate removal has contributed to fish population declines.

Changes in water velocity and temperature have also affected native aquatic species in the HEC. Creation of a deep-draft (27 ft) shipping channel (Larson 1981) reduced water velocity over spawning substrates at 13 historic reputed fish spawning sites in the St. Clair and Detroit Rivers (Goodyear et al. 1982). Large-volume discharges of heated water from numerous industries, power plants, and municipal sewage treatment plants on both sides of the river may have affected the thermal “window” for spawning fish. Lake sturgeon, for example, spawn at water temperatures between 11-15°C. Due to the higher water temperatures, sturgeon may be spawning prior to production of suitable food resources in their nursery habitat downstream, reducing their survival and successful recruitment. In addition, successful restoration/rehabilitation of native aquatic species and habitats in the HEC also requires knowledge of the hydrology of the system. For example, low velocity, vegetated habitat, important in the life history of many aquatic organisms, is largely lacking in many parts of the HEC.

2) Effects of aquatic invasive species on native aquatic species
Non-native aquatic organisms were first discovered in the Great Lakes in the early 1800’s, with the total number of established species now estimated at 162 (Ricciardi, 2001). More than one-third of these organisms have been introduced in the past 30 years, coinciding with the opening of the St. Lawrence Seaway (GLC 1992) and resulting in both biologic and economic consequences to the Great Lakes region. The most problematic invasive species include alewife, common carp, Eurasian ruffe, quagga mussel, rainbow smelt, round goby, sea lamprey, spiny waterflea, and zebra mussel. These species alone have contributed to massive extinctions of native fauna and severe alterations of food webs in the Great Lakes. Negative effects of invasive species include competition with native species for food, habitat, and spawning sites, and predation on native species.

Invasive species have had major economic impacts in the Great Lakes region as well. For example, zebra mussels have caused millions of dollars of damage to municipal and industrial water intake pipes. Sea lamprey have greatly reduced populations of commercial and sport fishes, such as lake trout and lake whitefish, resulting in lost income for commercial and recreational fisheries. Round gobies prey on lake sturgeon eggs contributing to the decline of sturgeon populations (Nichols et al. 2003).

Great Lakes managers and resource users presently need information on all aspects of potential and existing invasive species, including basic biology, geographic distribution, and potential impact on existing biota. Working together and using a proactive research approach we will develop strategies that can help managers respond effectively to current and potential invasive species issues in the HEC.

3) Conservation biology of native species.
Conserving the aquatic biological diversity of the HEC is an essential component of this Initiative. Maintaining healthy and productive aquatic ecosystems throughout the Corridor benefits the human population as well as the organisms inhabiting these waters. Over 500,000 boats are registered in Michigan and use the HEC waters for sport and commercial fishing and other recreational activities. HEC waters are also a source of drinking water and process water for industry. Changing land use, invasive species, coastline development, and many other factors have impacted native species and their habitats within the HEC. The Restoration Ecology and Invasive Species research themes already discussed interrelate well with the Conservation Biology theme because research results should ultimately contribute to the maintenance of biological diversity and ecosystem resiliency.

The development of research strategies and relevant new science are key objectives of the HEC Initiative. Our partners believe that habitat restoration should be a primary research focus in the HEC. Initial research needs and priorities were determined through discussions with the HEC Initiative steering committee at annual meetings in February of 2005 and 2006. It was decided, by consensus, that initial research should focus on:

Compiling historic HEC habitat and data resources
Current habitat function