Introduction
Wetlands habitats provide the world ecosystems with one of the richest biodiversity potentials, making them focal points of concerted conservation efforts the world over. The transitional role played by wetlands between aquatic and land habitats presents them as unchallenged options for wildlife and fish species (NOAA, 2013). Evidenced by the impeccable species abundance, diversity, and quality in health and fitness, wetlands remain a vital conservation highlight. This study focuses on the Great Lakes coastal wetlands habitat conservation status, against a backdrop of myriad challenges affecting conservation efforts of delicate habitats. Using biological indicators that point at the level of challenges at the Great Lakes coastal wetlands habitat, the conservation status characterization takes the form of a discussion backed by academic authority. Indicators relied upon in this conservation characterization include plants, microinvertebrates, fish, birds, amphibians, and covariates (Danz, Kelly, and Niemi, 2007).
The Great Lakes Coastal Wetlands Habitat
One of the most significant freshwater natural resources in America and indeed in the entire world, the Great Lakes spanning over 750 miles provide a home to thousands of species. Studying the Great Lakes ecosystems requires a clear delineation to define the scope of the study, which implies that the wetlands, in this case, will require a clear identification (Brown, Ciborowski, Hollenhorst, Host and Johnson, 2007, p13). Some of the threats include the invasion of aquatic life forms by destructive species as well as habitat loss. Such threats affect the fish species that the Great Lakes habitats have hosted for centuries.
Avian botulism poses a considerable threat to bird species around the Great Lakes and patterns of the threat in the habitat indicate that conservation efforts must step up to the challenge. The water levels of the Great Lakes over the years, coupled with other related challenges such as climate change, imply that the life of the habitat depends on the delicate water volume factors. Other related water factors of the conservation status of the Great Lakes around water diversions, which hinge on the shoreline management efforts also contribute to the status of habitats (NOAA, 2013). In addition, non-point source pollution and sewer overflows from the human activities around the habitats pose the challenge of nutrients and minerals inflow into the waters. An illustration of chemical interaction with the Great Lakes and how it affects conservation perhaps comes from a consideration of the impact that pharmaceuticals have in lake waters.
Plants
Plantlife as an indicator of habitat integrity around the Great Lakes coastal habitat illustrates a pattern of diminishing potential of the wetlands to accommodate thousands of different species. Plant varieties supporting various fishes and other herbivorous and omnivorous species appear to face survival challenges, thereby exposing the dependent species to risk. The approach adopted by prominent studies on the level of degradation of the Great Lakes concerning plants adopts a mechanism that accommodates missing information (Albert and Minc, 2004). The missing information on the plant life aspect of the habitats relates to the fact that the Index of Biotic Integrity (IBI). IBI refers to the classification and characterization of water pollution concerning life indicators, in this case, represented by plants. Attempts to construct reliable vegetation-based IBI for the whole habitat faced challenges including the vast area to cover and water level fluxes against a myriad of disturbances in the habitats.
In terms of the Great Lakes plant indicators, invasive plants observed in the wetlands illustrate the high magnitude of disturbance posed. This implies that risks posed to the species dependent on the traditional plant life equally rise. The presence of invasive plant species as an indication of disturbance highlights the level of integrity compromise for the habitat, exposing the ability of the wetlands to accommodate species richness expected from undisturbed wetlands to inadequacies (Brown et al, 2007). The presence of marsh zones emerging from such invasions degrades the quality of the vegetation to accommodate its traditional beneficiaries. Among the commonest disturbance factors, nutrients commonly relayed to the wetlands as animal waste sedimentation, as well as fertilizers, degrade plant life. Alternatively, sedimentation as a way of disturbance entry leads to drier and bare wetlands zones, which dramatically reduce plant cover (Albert, Wilcox, Ingram, and Thompson, 2006). Invasive plants, many of which reduce habitat’s ability to support other life forms, compete with the native varieties and expose the habitat to conservation dangers mentioned above.
Assessing the distribution of the emergent vegetation arising from invasive varieties in the Great Lakes illustrates a worrying challenge in need of urgent conservation effort. Equally, submerged vegetation assessments illustrate the presence of floating plants, which pose a risk to water quality and other life forms around the lakes. Equally, recent aerial images of the Great Lakes coastal wetlands in comparison with old similar images illustrate massive habitat loss, with receded plant cover observed in the analyses (Albert and Minc, 2001). Computation of the plant communities in the Great Lakes using the Floristic Quality Assessment (FQA) that determine the suitability of the habitat to different varieties of plants in the habitat also give useful information on the degradation status of the wetlands. Computer applications for FQA procedures facilitate easier characterization of conservation in different projects as presented by Brodowicz et al. (2011). The development of the conservatism indices of the plants in the wetlands habitats in the Great Lakes indicates invasive plants degrading the ability of the habitat to remain intact.
Fish
Over 80 species of fish find a home in the Great Lakes coastal wetlands, with over a half of them having a permanent home in the wetlands. The rest of the species find the wetlands as vital transitionary habitat at least once in their life cycles (Brazner, Burton, Ciborowski, and Uzarski, 2008). Fish-based indicators in the Great Lakes coastal wetlands perhaps provide the best assessment of the quality of aquatic life supported by the challenging habitat. Various studies conducted on the Great Lakes provide fish indices over time and the outcomes about fish communities against the backdrop of water quality. Given the changes, different zones have different challenges exposed to the fish communities and the pressure studied illustrates the diminishing capability of the Great Lakes coastal wetlands habitats to support fish species richness and diversity reduce with increased stress to the habitats (Seilheimer, 2006).
The loss of coastal wetlands as documented around the Great Lakes ranges between 50 percent and over 90 percent in the last century at different locations. For instance, documented loss at the west side of Lake Erie points at a possibility of over 95 percent loss. This implies that the loss makes the fish communities exposed to uninhabitable conditions as the ecological integrity of the lost wetlands ranks below the biotic expectations for the species (Brazner et al., 2008). Fish-based IBI considering biotic metrics illustrate that the Great Lakes exotic fishes continue to experience pressure from the challenges around the habitat. Water quality in the Great Lakes coastal wetlands facilitated the development of fish-based IBI, where records taken over the years illustrated certain trends explaining dwindling fish habitats.
Capturing fish from different sample habitat zones coupled with the water quality assessment provides explanations to anomalies of samples over the years (Corkum, LaPointe, and Mandrak, 2006). Abnormalities in the fish captured in the various wetlands habitat under threat indicate the magnitude of degradation pressure, usually in terms of the water quality. Samples over the years indicate that the fish captured had black spots, anchor worm, eroded fins, lesions, fungi infestation, blinded, tumors, emaciated, swirled scales, leeches infestation among other parasites infestations (Brazner et al., 2008).
Alternatively, the abundance of different fish species from several habitat locations over the years indicates the level of the threat posed to the Great Lakes and the characterization continues over several years. The authors observed that kind of fish capturing technique used also determines the success of the profiling. Fyke nets produced the best results in characterization procedures in the Great Lakes, as opposed to electrofishing or other techniques (Bhagat, 2005). Fish indicators from surveys conducted in recent years highlight the need for improved wetland management and conservation efforts to reduce habitat disturbance. Using techniques such as wetland Water Quality Index (WQI), fish-based indices provide useful explanations to the dwindling fish communities in the Great Lakes coastal wetlands habitats (Chow-Fraser, 2006).
Amphibians
The role of amphibians in a biotic indication of habitat integrity comes into perspective since their standard life relies on aquatic and intermediary conditions as perfectly provided in wetlands environments. Most amphibian species spend their entire history in wetland-like conditions, particularly anurans. The sensitive nature of amphibians to aquatic and other environmental conditions, for instance about interactions with pollutants, makes them uniquely valuable and reliable degradation yardsticks. The Great Lakes have recorded numerous anuran species due to the extensive wetland conditions over the years, but the degradation element experienced over the years compromises these habitats (Hanowski et al., 2007).
Among the most reliable reasons for the dwindling populations and diversity of anuran species in the Great Lakes coastal wetlands, habitat loss and entry of pollutants perhaps contribute the largest value (Corkum et al, 2006, p504). Comparing the population declines in the Great Lakes with the trends observed in the global scenes illustrates the extent of the dangers of climate change. In other parts of the world, the decline in amphibian populations and diversity projected from the biotic sensitivity showed massive threats exposed by several factors.
Climate change factors exposing amphibians to life-threatening challenges include emerging invasive species, skin conditions from solar radiation, and diminishing food sources among other factors. Sensitive skin enables amphibians to play a perfect role in an indication of dangerous toxic chemicals in the wetlands, as well as accumulation of minerals and sediments likely to affect reproduction and survival of the species (EPA, 2005). Perhaps habitat loss ranks top among these factors, against a host of human activity-intensive disturbances that expose the amphibians to sensitive stressors. Stressors effectively reduce the fitness of the anurans in a slight change as experienced with the shifting of temperatures over the centuries. With climate change dangers still looming in the current habitat factors, Great Lakes coastal wetlands still experience threatening times ahead unless conservation efforts mitigate the pressure.
Reduced water levels and related frequent fluctuations imply that the Great Lakes’ potential to provide a breeding ground for the species reduces accordingly. The presence of stable water levels in the wetlands provides amphibians with breeding habitats, which when compromised lead to the associated disturbances degrading the necessary conditions (Corkum et al, 2006). Among the applied metrics in the amphibian-based index includes species richness in the wetlands and the possibility of detecting woodland amphibians in the surveyed regions during the characterization. The different disturbance tolerance abilities of the various species facilitate the characterization of the species. In the data presented for different wetlands, reduced amphibian richness corresponded with the observation that habitat loss and disturbance increase in the Great Lakes coastal Wetlands directly contribute to population declines (Crewe, Grabas and Timmermans, 2008). Among the documented frogs and toads by the Marsh Monitoring Program (MMP) and Great Lakes National Program Office conservation management efforts, American toad, leopard frog, pickerel frog, cope’s grey tree frog, and spring peeper recorded the greatest declines. Significant declines also documented touched on chorus frogs previously distributed in vast regions, as well as the green frogs, wood frog, Blanchard’s cricket frog that showed massive population dip. Even though the period between 1995 and 2002 represented by the MMP would present scanty information under normal habitat conditions, the disparities witnessed in populations before and after the study indicate the nature of the threat posed to the habitat (EPA, 2005). Long-term trends might give different trends in terms of species adaptation to environmental stressors, but climate change poses the strongest danger to doubt the data.
Birds
A majority of threatened and endangered avian species in America inhabit the Great Lakes coastal wetlands, particularly in Ontario. The life cycle of the marsh-dependent birds deep into the wetlands has presented researchers with difficulties in profiling their entire life traits in terms of conservation demands. Highly secretive life deep in the marshes makes it difficult for studies to proceed with accurate projections (Estey, Higgins, Johnson, and Naugle, 2001). However, observable patterns of decline in populations attributable to obvious habitat degradation have emerged over the years. Possible causes of habitat degradation and loss include industrial activity around the Great Lakes as well as agricultural development. Disturbance of traditional breeding grounds for the birds could result in migration and reduced fitness affecting reproduction and survival (Danz, Hanowski, Howe, Niemi and Regal, 2007).
Marsh quality under stresses such as reduced water quality and receding water levels also imply that the populations lose standard conditions for their life processes to proceed. Marsh purposes in the various bird varieties life processes include nesting as well as foraging, which depend on various aerial and water qualities. Several stressors affecting aerial and water quality as mentioned above imply that the avian species find obstacles in their foraging and nesting needs, thereby affecting their fitness. Sampling the location for study over a specified period enables researchers to observe bird species in the profiling which enables learning of the population stresses (Danz et al., 2007, p245).
Macroinvertebrates and Covariates
Benthic macroinvertebrates attribute the level of organic nutrient recycling and the quality of lake water in terms of organic life depend on the use of these organisms as a fair indicator. The ability of macroinvertebrates to recycle nutrients and energy enables them to play a vital role in food webs at the decomposer’s level. Changes in populations of benthic macroinvertebrates in the Great Lakes with massive nutrient and contaminants inflows illustrate the high activity of these recyclers (Albert and Minc, 2001, p3414). An illustration of the amphipod Diporeia whose density in water samples collected at different offshore and nearshore waters could lead to the determination of benthic energy recycling activity.
As expected from a highly diversified ecosystem, several taxa of macroinvertebrates exist from samples picked at different sites in the Great Lakes including Oligochaeta, Hirudinea, Chironomidae, Sphaeriidae, among many more (Nalepa, 2013). The higher the mineral and energy recycling demands of the Great Lakes, the higher the population of macroinvertebrates, which also depend on the conditions of vegetation, supported. Different covariate stressors recorded in different sites range from dieldrin, phosphocarbonates to mercury as reported in Lake Superior (EPA, 2010). In Lake Ontario and the others, contaminants such as furans, phosphocarbonates, DDT, dieldrin, as well as mirex and mercury also exist, with conservation measures reducing some of the contaminants over the years (EPA, 2006).
As indicated by each of these indicators, the integrity of the Great Lakes experiences challenges from different stressors, which must meet efforts to sustain biodiversity in the Great Lakes coastal wetlands ecosystems. With increasing threats from climate change and emerging dangers in the contemporary environment, studies must provide information to bridge the gap in conservation techniques. Whereas natural processes must continue with little mitigating efforts, human activities must fall within bearable climatic deviations. Conservation of wetlands habitats remains one of the most critical efforts to protect remaining rich natural resources. The Great Lakes ecosystems must form part of the entire global attention in the protection of the greatest remaining ecological treasures.
References
Albert, D. A., & Minc, L. D. (2001). Abiotic and floristic characterization of Laurentian Great Lakes coastal wetlands. Very International Verein Limnology, 27, 3413-3419.
Albert, D. A., & Minc, L. D. (2004). Plants as regional indicators of Great Lakes coastal wetland health. Aquatic Ecosystem Health and Management, 7(2), 233-247.
Albert, D. A., Wilcox, D. A., Ingram, J. W., & Thompson, T. A. (2006). Hydrogeomorphic classification for Great Lakes coastal wetlands. J. Great Lakes Res 31(1):129-146.
Bhagat, Y. (2005). Fish indicators of anthropogenic stress at Great Lakes coastal margins: Multimetric and multivariate approaches. Web.
Brazner, J., Burton, T., Ciborowski, J. & Uzarski, D. (2008). Fish community indicators. Web.
Brodowicz, W. W., Herman, K. D., Masters, L. A., Penskar, M. R., Reznicek, A. A., & Wilhelm, G. S. (2011). Floristic quality assessment with wetland categories and computer application programs for the State of Michigan. Web.
Brown, T., Ciborowski, J., Hollenhorst, T., Host, G., & Johnson, L. (2007). Methods of generating multi-scale watershed delineations for indicator development in Great Lake coastal ecosystems. Journal of Great Lakes Research, 33(3), 13-26.
Chow-Fraser, P., (2006). Development of the wetland Water Quality Index (WQI) to assess effects of basin-wide land-use alteration on coastal marshes of the Laurentian Great Lakes. Bloomington: AuthorHouse.
Corkum, D., LaPointe, N. R. & Mandrak. N. E. (2006). A comparison of methods for sampling fish diversity in shallow offshore waters of large rivers. North American Journal of Fisheries Management 26, 503–513.
Crewe, Grabas and Timmermans, (2008). Amphibian community indicators. Web.
Danz, N., Hanowski, J., Howe, R., Niemi, G. & Regal, R. (2007). Considerations for monitoring breeding birds in Great Lakes coastal wetlands. Journal of Great Lakes Research, 33(3), 245-252.
Danz, N., Kelly, J. & Niemy, G. (2007). Environmental indicators of the coastal region of the North American Great Lakes: Introduction and prospectus. Journal of Great Lakes Research, 33(3), 1-12.
EPA, (2005). What is the state of Great Lakes Amphibians? Web.
EPA, (2006). What are the current pressures impacting Lake Ontario? Web.
EPA, (2010). What are the major stressors impacting Lake Superior? Web.
Estey, M. E., Higgins, K. F., Johnson, R. R. & Naugle, D. E., (2001). A landscape approach to conserving wetland bird habitat in the prairie pothole region of eastern South Dakota. Wetlands, 21, 1-17.
Hanowski, J., Howe, R., Niemi, G., Regal, R., Price, S. & Smith, C. (2007). Are anurans of Great Lakes coastal wetlands reliable indicators of ecological condition? Journal of Great Lakes Research, 33(3), 211-223.
Nalepa, T. (2013). Assessment of benthic macroinvertebrate communities in the Great Lakes. Web.
NOAA, (2013). Great Lakes region. Web.
Seilheimer, T. (2006). Development and use of fish-based indicators of wetland quality for Great Lakes coastal wetlands. Web.