Proceedings of the Workshop on the Creation of Channels and Ponds Within Cattail Marshes on the Bay of Quinte, and a Conceptual Plan
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PROCEEDINGS OF THE WORKSHOP ON THE CREATION OF CHANNELS AND PONDS WITHIN CATTAIL MARSHES ON THE BAY OF QUINTE, AND A CONCEPTUAL PLAN. PREPARED BY ANDY SMITH BAY OF QUINTE REMEDIAL ACTION PLAN JANUARY, 1995 PREFACE On August 17 and 18, 1994 a workshop was held to bring together scientists and members of , , the Bay of Quinte Implementation Advisory Committee (formally the Public Advisory Committee) to discuss enhancing Quinte wetlands by dredging channels and ponds in dense cattail stands. The goals for the workshop were to review the impacts of this technique, discuss its advantages and disadvantages, and design a new channel/pond system. This report is a summary of the workshop and a conceptual plan for a project based on recommendations from the workshop. If implemented this experimental/demonstration project will be studied to determine the effectiveness of creating open water areas within dense cattail stands for providing habitat for variety of species. TABLE OF CONTENTS 1.0 Workshop Introduction ...................................... 1 2.0 Summary of Workshop Presentations and Discussions:~,' ................. 3 2.1 A Literature Review of the Impacts to Wildlife of Channel Creation Through Monotypic Cattail Stands as Proposed at the Bay of Quinte Area of Concern 3 2.2 Studies Conducted on Wetlands in The Quinte Area, 1994 ........... 4 2.2.1 Review of Some Recent Wetland Enhancement Projects in the Quinte Area and Creation techniques. 4 2.2.2 Fisheries Assessment of Some Wetland Enhancement Projects in the Quinte Area . 5 2.2.3 List of Plants and Animals Observed During the Tour of Sawguin Creek Marsh, August 17, 1994 ........................... 6 2.2.4 Studies of Marsh- and Waterbirds on the Bay of Quinte, 1994 .... 7 2.3 Discussion on the Benefits and Drawbacks of Channel Creation as a Method of Enhancing a Wetland . .. 8 2.4 Discussion on the Design of a New Channel/Pond Project on the Bay of Quinte .. .. 10 3.0 A Plan for a New Channel/pond Project in a Cattail Marsh on the Bay of Quinte . 12 3.1 Background Information . .. .. 12 3.2 The Design. .. .. 14 3.3 Methods for Creating Openings in Emergent Marshes. .. 17 3.4 The Method Recommended for Construction .................. 18 3.5 Environmental Assessment and Permit Requirements ............. 19 3.6 Location. .. 21 4.0 Conclusion............................................. 22 5.0 Acknowledgements ....................................... 23 6.0 References............................................. 24 Appendix 1: Diagrams of a Conceptual Plan for a Channel/pond Creation Project. Appendix 2: List of Workshop Participants. Appendix 3: Common and Scientific Names of Species Mentioned in the Text. Appendix 4: Workshop Agenda. 1.0 WORKSHOP INTRODUCTION Alastair Mathers, Workshop Organizer, Ontario Ministry Of Natural Resources , ~ "" The Quinte RAP Habitat Working Group held this workshop to evafuate the approach of creating channels in large 'mono-typic' cattail mats as a method of increasing habitat diversity. The purpose of the workshop was to provide information on what is known about the technique. In addition, the working group hoped to gather input from people with a variety of backgrounds, not to seek approval of any agency or individual. Input was sought on two questions: 1) is channel creation or similar techniques worthwhile? 2) what features should be included in the design? Prior to implementation of any project of this nature the working group will have to consider a variety of environmental protection regulations including the Environmental Assessment Act, Environmental Assessment and Review Process, Area of Natural and Scientific Interest, and the Wetlands Policy, and seek approvals as necessary. In addition, partners will need to be identified to help with funding and implementation. Channel creation projects are being considered as one of the tools which could prove useful in the 'Bay of Quinte Wetland Management Plan'. The habitat working group will be developing the plan as described in the RAP. Other tools which are likely to contribute to the management plan would include protection of wetland habitats, and creation of new habitats. Channels have been created in Bay of Quinte wetlands recently, and the impact of these habitat modifications have been studied for the past two years. It is hoped that these studies will provide useful information for management on both the Bay of Quinte and other wetlands. There are two reasons why construction of channels should be considered. Construction of channels in mono-typic cattail stands will increase the diversity of wetland habitats by increasing the amount of habitat edge and the abundance of submergent aquatic plants. Increasing these habitats should encourage more diverse wildlife populations. For example, creating channels will provide spawning and nursery habitats for pike and largemouth bass, two fish species which are currently at low abundances in the Bay of Quinte. The understanding of which species will 1 benefit from channel creation is not perfect, however, a variety of community ecology studies have shown that more diverse habitats tend to have larger numbers of species and more 'balanced' ecosystems. , , An additional reason to consider channel creation as a management tool is that this technique should rehabilitate coastal wetlands to a more natural state. Quinte's wetlands were once more open, less dominated by cattails, and described as 'lush weed beds with very abundant wild rice'. The change towards wetlands which are dominated by cattails is in part due to the natural process of succession which has be observed in many plant communities. However, there is some evidence that human activities including regulating water levels, adding silt to wetlands through agricultural and forestry activities, and adding nutrients to the Quinte ecosystem may have encouraged the dominance of cattails. It can not be shown conclusively that human activities are at the root of the changes to Quinte's wetland, however, the ability of cattails to dominate large areas of wetland, and replace historic species has been documented elsewhere. 2 2.0 SUMMARY OF WORKSHOP PRESENTATIONS AND DISCUSSIONS 2.1 A Literature Review of the Impacts to Wildlife of Channel Creation , ~., '.' '.', Through Monotypic Cattail Stands as Proposed at the Bay of Quinte Area of Concern. Cynthia Pekarik, Consultant In marshy areas dominated by one plant species level ditching is believed to increase marsh productivity. Creating a series of openings leads to greater interspersion, thus creating niches for more species of animals (D. McLachlan, pers. comm.). A 50:50 ratio of vegetation to open water (hemi-marsh) has been found to be the one with most avian species diversity (Weller, 1975; Sodja and Solberg, 1993). Research to date presents us with evidence that level ditching can lead to an increase in the number of invertebrates, fish, mammals and birds utilizing a given area. Aquatic and benthic macroinvertebrates numbers from the herbivore-detrivore group increased subsequent to marsh manipulation. Mudminnows, pike and carp have been sighted in level ditches. Coots, red-winged blackbirds, black terns, pied-billed grebes, common gallinules, virginia rails, mallards, blue-winged teal, redheads, marsh wrens, pintails, lesser scaup, and northern shovelers were species who have exhibited increased breeding success in marshes where· the rate of interspersion between water and emergent vegetation has been manipulated to resemble a herni-marsh. American bittern, least bittern and long-billed marsh wren popUlations remained constant. great blue herons, green herons, great egrets, black ducks, common terns, and belted kingfishers seem to make use of interspersion for feeding. The breeding densities of swamp sparrows and ring-necked pheasants decreased. Muskrat popUlations should grow after opening up a marsh. Designs will vary according to individual conditions and the species meant to benefit, nonetheless the environment to aim for is one composed of islands of vegetation surrounded by water. Pools of water at least 30 feet in diameter are recommended. Ditches should be dredged 3 to a depth of 1.2 metres below the spring/summer water level and they should reach the inorganic substrate. The design of choice is a sinuous pattern varying in width from 3,7 to 6 metres. Care should be taken with spoils so as not to create a dyke or allow predator access to nests. , , References McLachlan, Dave. Ducks Unlimited (Canada), Barrie, Ontario. Sojda, R.S. and K.L. Soldberg. 1993. 13.4.13. Management And Control Of Cattails in Waterfowl Management Handbook. Fish and Wildlife leaflet 13. United States Dept. Inter. Fish and Wildl. Servo Washington D.C. 8 pp. Weller, M.W. 1975. Studies of Cattail in Relation to Management for Marsh Wildlife. Iowa State J. Res. 49:383-412. 2.2 Studies Conducted on Wetlands in the Quinte Area, 1994. 2.2.1 Review of Some Recent Wetland Enhancement Projects in the Quinte Area and Creation Techniques. Andy Smith, Ontario Ministry of Natural Resources Wetland enhancement was carried out at Saguin Creek Marsh, Little Cataraqui Marsh and Big Island Marsh by creating open water channels in dense homogeneous stands of cattail. The channels were dug using a floating backhoe. The compact size and its ability to "walk" through dense marsh allow the backhoe to access many sites and results in little disruption of non target areas. Dredged material (muck) is piled on the edge of the channel to weigh down the cattail mat and reduce the chance of it spreading into the channel. Channels are approximately 3 to 4 metres wide and 0.75 to 1 metre deep at high water. The cost for contracting the floating backhoe and operator is $85/hour (1993). He is able to construct 12-20 metres of channel 3-4 metres wide 4 and 0.75-1 metre deep per hour. Channels were dug in Pine Point Wetland in 1992 to provide boat access to the Bay of Quinte and to improve fish and wildlife habitat. The altered area CDnsisted of dense cattail marsh, willow and alder swamp, and upland.