Wye Marsh Trumpeter Swan Population: A Database Analysis

Please download to get full document.

View again

of 44
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Information Report
Category:

Poems

Published:

Views: 0 | Pages: 44

Extension: PDF | Download: 0

Share
Related documents
Description
Wye Marsh Trumpeter Swan Population: A Database Analysis ERS 490B Final Report Submitted by: Nick Bartok RR#2 Fraserburg Road Bracebridge, Ontario P1L 1W9 Submitted to: Greg Michalenko
Transcript
Wye Marsh Trumpeter Swan Population: A Database Analysis ERS 490B Final Report Submitted by: Nick Bartok RR#2 Fraserburg Road Bracebridge, Ontario P1L 1W9 Submitted to: Greg Michalenko May 2003 Table of Contents 1.0 Lists List of Figures List of Tables List of Appendices Acknowledgements Abstract Introduction Purpose Background Wye Marsh Wye Marsh Wildlife Centre The Trumpeter Swan Historical Populations Wye Marsh Population Ontario Population North American Population Scope and Objectives Study Area/Scope Objectives Methods Statement about the Database Database Creation Tagging and Banding Monitoring / Data Collection Health Monitoring - Lead Poisoning Detection Results from the Database Wye Marsh Population and Sex Ratio Age Dynamics (Productivity) Nesting Productivity Causes of Death Lead Poisoning Number of Deaths and Number Treated Age Class Affected Discussion Quality and Quantity of Data Population Projections (growth) Nesting Dynamics Nesting Results Nesting Results Comparison Comparison between Wild and Captive Nesting Productivity Lead Poisoning History of Lead Poisoning at Wye Marsh Age Classes Affected by Lead Poisoning Conclusion Recommendations and Future Study References...39 1.0 Lists 1.1 List of Figures Figure 1 - Canadian Wildlife Service/Ontario Ministry of Natural Resources Property in Wye Valley Figure 2 - Aerial Photograph of the Wye Marsh Wildlife Centre Figure 3 - North American Swan Comparison Figure 4 - Trumpeter Swan Distribution Figure Distribution of the Trumpeter Swan Figure 6 - Trumpeter Swan Being Tagged Figure 7 - Readable Tag After Tagging Figure 8 - Trumpeter Swan Population Trend for Wye Marsh and Ontario Figure 9 - Population Trends: Fledglings Figure 10 - Number of Swans by Age Class and Sex Figure 11 - Average Age by Sex Figure 12 - Life Span by Sex Figure 13 - Causes of Death Figure 14 - Lead Poisoning Deaths and Treatment by Year Figure 15 - Treatment of Lead Poisoning by Sex Figure 16 - Lead Poisoning deaths by Age Class 1.2 List of Tables Table 1 - Number of Swans Treated by Type of Treatment Table results for Trumpeter swan pairs known to nest within the Wye Marsh Table results for Trumpeter swan pairs known to nest outside the Wye Marsh Table 4 - Nesting comparison of known nests in the Wye Marsh and surrounding area, List of Appendices Appendix A - Satellite Image of the Wye Valley Appendix B - A Partial Copy of the Microsoft Access Database Appendix C - Daily Monitoring Form Appendix D - Known Nesting Pairs Since 1988 and Their Success 2.0 Acknowledgements Special thanks go out to many people involved in the Trumpeter Swan Reintroduction program in Ontario. I would like to thank the Wye Marsh Wildlife Centre and staff for their continued support, especially executive director Laurie Schutt. I am grateful to Harry Lumsden for providing me with some of the information found within the database and I look forward to continuing my research with him in the future. Thanks to Greg Michalenko for direction and support over the last eight months in preparing this thesis. I especially would like to thank April Mathes, the current Trumpeter Swan Reintroduction Program Coordinator at the Wye Marsh Wildlife Centre, for putting up with my constant questions. Without her help, finding and compiling data for this project would have been much harder and taken longer. Thanks to everyone. 3.0 Abstract Wye Marsh, located on the southeastern shore of Georgian Bay on the boundary of Midland, Ontario, contains about 500 hectares of provincially significant wetland. The Wye Marsh Wildlife Centre, managed by the Friends of Wye Marsh Inc., has been a main co-operator since 1988 in the Trumpeter Swan reintroduction program in Ontario, cocoordinated by Harry G. Lumsden. In 2002, 115 individual Trumpeters visited the Wye Marsh; 86 of these are tagged and/or banded. This represents nearly one-third of the total Ontario population, estimated to number 406 swans in 2002 (Lumsden, 2003). The creation of a Microsoft Access database now holds all of the available information on every Trumpeter Swan that has visited the Wye Marsh in the last 15 years, since the Friends of Wye Marsh Inc. became a co-operator. With 191 entries or individual swans, much has been learned about the general population characteristics. The Wye Marsh population has now reached 89 marked swans, since starting with a captive breeding pair in As of December 31, 2002, the average age of presently living swans is 4.40 years for males and 4.77 for female. For swans that have died, the average lifespan for males is 3.07 years and 3.45 years for females. The total number of pairs nesting is 29 (27 wild, 2 captive) with 24 pairs producing offspring that have fledged. Lead poisoning is the major known cause of death with 30 confirmed cases; 33 cases have been treated for lead poisoning, resulting in 14 deaths during treatment and 19 released after treatment. The juvenile age class appears to be the class most affected by lead poisoning, with 16 of the 30 deaths; this should be studied further in the future. 4.0 Introduction 4.1 Purpose The purpose of this thesis is to create and analyze a Microsoft Access Database that contains information on every Trumpeter Swan that has visited the Wye Marsh. Analysis of this database will provide a greater understanding of the Trumpeter Swan population visiting the Wye Marsh throughout each year since 1988 when the Wye Marsh Wildlife Centre became the main co-operator in the Trumpeter Swan Re-introduction Program in Ontario. 4.2 Background 4.2.1Wye Marsh Becoming recognized as a Provincially Significant wetland in 1987, the 500 ha Wye Marsh is nestled on the southeastern shore of Georgian Bay in the Wye Valley. Located just outside the town of Midland, Ontario (a two hour drive northwest of Toronto), the Wye Valley (See Figure 1) includes the 920-hectare provincially owned Wildlife Area and 60 hectares of federally owned property (Bowles 2002). (Figure 1 - Canadian Wildlife Service/Ontario Ministry of Natural Resources Property in Wye Valley) (Severn Sound Environmental Association, 2001) The Wye Marsh can be considered outstanding in that three different types of wetland exist there: marsh, fen and swamp, each adding to the complexity and natural beauty of the marsh. Mud Lake, found within the Wye Marsh, is slowly being filled by floating mats of cattails, the dominant vegetation found in the marsh, but also provides prime habitat for many nesting bird species. The Wye Marsh is also recognized as an Important Bird Area because several Species at Risk, as designated by the Ontario Ministry of Natural Resources, use the Wye Marsh for nesting and staging. These bird species include: the Trumpeter Swan (Cygnus buccinator, indeterminate), the Black Tern (Chlidonias niger, vulnerable), the Least Bittern (Ixobrychus exilis, vulnerable), the King Rail (Rallus elegans, endangered), and the Yellow Rail (Coturnicops noveboracensis, vulnerable) (OMNR 2002) Wye Marsh Wildlife Centre The Wye Marsh Wildlife Centre is situated on the federally owned property, in the northeastern portion of the Wye Valley (See Appendix A), and hosts many environmental education programs and events. Opened in 1970 by the honourable Jean Chretien who at the time was the Minister of Indian and Northern Affairs, the centre became an international tourist attraction along side with Ste. Marie Among the Hurons, a historical Jesuit Missionary site and Martyr s Shine, a Catholic church in honour of the many historical martyrs in the Midland area. These three attractions see hundreds of thousands of tourists and visitors each year, with the Wye Marsh Wildlife Centre receiving about 30,000. In 1987, management was passed from the federal government of Canada to the non-profit organization, Friends of Wye Marsh Inc. In 1988 the Friends of Wye Marsh became a co-operator in the Ontario Trumpeter Swan Re-introduction program by purchasing a captive breeding pair of swans. (Figure 2 - Aerial Photograph of the Wye Marsh Wildlife Centre) The Trumpeter Swan A former native breeding species in Ontario, the Trumpeter Swan was extirpated by the end of the 1800 s (Coxon, 2002a). Populations remaining on the west coast of Canada and the United States were severely affected by over-hunting with the population thought to be extinct by 1900; however, it is now known that a population of several thousand Trumpeters survived in remote parts of Alaska and Canada (State of Wisconsin, 2003). Populations across North America have since rebounded with tens of thousands in the largest population on the West Coast. The beautiful and intriguing Trumpeter Swan is one of two swan species native to Canada, the other being the Tundra Swan (Cygnus columbianus) that also suffered extreme population losses due to over hunting. The European Mute Swan (Cygnus olor) is now established in Ontario and the northern U.S (See Figure 3). The Tundra Swan migrates over Ontario by the tens of thousands in early spring and late fall. Figure 3 outlines some of the distinguishing features of the two native species of swan, including the introduced Mute Swan. The Trumpeter Swan is North America s largest waterfowl, reaching a length of metres and a wingspan of nearly 2.4 metres, while the Tundra Swan only reaches a length of metres and a wingspan of 2.0 metres (Bezener, 2000). Male Trumpeters or cobs typically reach 30 pounds while the female pens can be 25 pounds; baby swans are called cygnets, coming from the Latin word Cygnus, meaning swan. Each species of swan also has a distinctive call: a loud honking sound is made by the Trumpeter and a high pitched quivering or whistling sound by the Tundra Swan, historically named the Whistling Swan. The Tundra Swan has a characteristic yellow patch between the eye and the nostril, which the Trumpeter does not regularly exhibit. However, two Trumpeters seen at the Wye Marsh Wildlife Centre do exhibit these yellow patches; no connection has ever been made to the possibility of crossbreeding between the two species. The Trumpeter Swan is entirely white, with black feet, black bill and characteristic red mandibles (upper and lower). At hatching the cygnets weigh about 8 ounces and are grey with pinkish beaks, legs and feet. By the time cygnets become juveniles, the pinkish colours have almost entirely become black, but they still retain their grey feather colour. Trumpeter Swans become mature at three years of age, at which time their feathers are entirely white (Wye Marsh Wildlife Centre, 2003). (Figure 3 - North American Swan Comparison) (WDNR, 2003) Historical Populations The Trumpeter Swans range once stretched across much of North America (Figure 4), with many explorers and fur traders reporting abundant numbers of swans on the St. Lawrence, lake St. Clair and Hudson Bay Lowlands of Manitoba, Ontario and Quebec. Figure 4 outlines the 1998 of the Trumpeter Swan, which has returned to some of its original range. Some earlier maps omit populations in Eastern Canada; however, archaeological sites in Newfoundland at Port au Choix and the Jesuit mission site at Ste. Marie-among-the-Hurons in Midland, Ontario, have found Trumpeter Swan bones, indicating a historical presence. It was unlikely, outside of the flightless moulting period, that aboriginals could kill large numbers of Trumpeter Swans with bow and arrow, but once firearms arrived from Europe, populations were reduced and extirpated in many areas (Lumsden, 1984). The large populations of Trumpeters then began to decline due to market hunting and the millinery trade; skins were used for ladies powder puffs and feathers were used to adorn fashionable hats in Europe. By 1900, Trumpeter Swans were thought to be extinct; however, two nests were found in Yellowstone National Park in 1919, and in 1932, 69 Trumpeters were documented in the Yellowstone region. We now know that a population of several thousand Trumpeters also survived in remote parts of Alaska and northwestern Canada (WDNR, 2003). (Figure 4 - Trumpeter Swan Distribution) (TTSS, 1998) 4.2.5 Wye Marsh Population In 1982 biologist Harry Lumsden initiated the Ontario Trumpeter Swan Reintroduction Program. The first captive pair was purchased by the Friends of Wye Marsh and arrived at the Wye Marsh Wildlife Centre in The female unfortunately died of natural causes in early 1989, but another pen was found and brought to the centre. This new pair was nicknamed Big Guy and Lady Girl (or Wye and Marie to some). In 1990, Wye Marsh staff witnessed the hatching of two eggs, the first Trumpeter Swan cygnets known to hatch in the Wye Marsh in over 200 years. A snapping turtle predated one of the cygnets shortly after hatching, while the other, a female, survived to become known affectionately as Pig Pen (Swan #100), who in 1993 raised the first known wild family of Trumpeter Swans in Ontario in over 200 years (Coxon, 2002a). The wild population of Trumpeter Swans visiting the Wye Marsh on a yearly basis is now estimated to be 115, 89 of which are either wing tagged, leg banded or both; the remaining 26 are unmarked birds. Figure 8 outlines the wild growth trend of marked swans from 5 in 1990 to 89 in Ontario Population Originally native to Ontario, the Trumpeter Swans extirpation from eastern Canada was primarily due to hunting pressure (Coxon, 2002a). Populations remaining in the western prairies were also severely affected by over-hunting and were eventually greatly reduced. These populations have since rebounded to the tens of thousands, while the Ontario population numbered 400 swans at the end of 2002 (Lumsden, 2002). The total Ontario population is now estimated at 406 after six additional cygnets were reported late in 2002 (Lumsden, 2003). In June 1993, 50 eggs were taken from wild nests on the Minto Flats west of Fairbanks, Alaska. The eggs were artificially incubated and 42 cygnets were raised and pairs were moved to co-operators around Ontario for rearing purposes (Lumsden, no date). Co-operators have been responsible for raising captive stock for release into the wild Ontario population. Offspring are then moved to a holding facility at Fair Lake near Cambridge, Ontario, where they are held, tagged and released into the wild at two years of age. Releases occur across Ontario. Figure 8 outlines the Ontario population growth trend of all wild Trumpeter Swans. The main goal of the re-introduction program is to achieve a self-sustaining population in Ontario. The number of swans needed to achieve this is estimated to be and, according to the data analysis, the trendline estimates this number to be reached in the year 2005 (Lumsden, 2003) North American Population Figure 5 outlines the 1992 North American distribution of the Trumpeter Swans. Their distribution is broken down into three main populations: the Pacific Coast population (~15,000 individuals), the Rocky Mountain population (~2500 individuals), and the interior population, including Ontario (~900 individuals) (Matteson et al, 1995). These three populations compromise roughly 18,500 swans, significantly more than the total population size at the beginning of the 20 th century. The rebound in the total population is mainly due to re-introduction and protection programs across North America, with most populations still growing. (Figure Distribution of the Trumpeter Swan) (McKelvey, 1992) 5.0 Scope and Objectives 5.1 Study Area/Scope The study area for this project is the 500 hectare, provincially significant wetland known as the Wye Marsh. 5.2 Objectives This project has one main objective, to create a database holding all available information of Trumpeter Swans visiting the Wye Marsh, and thus gain a better understanding of this population. A secondary objective is to shed some light on the issue of lead poisoning and specifically determine the age class (cygnet, juvenile, adult) that has been affected the most by lead poisoning. This report is also intended to educate many people about Trumpeter Swans at the Wye Marsh and the difficulties of reintroducing a species back to its former range. 6.0 Methods 6.1 Statement about the Database The creation of the database was a very tedious task, with many hours of labour. For the sake of quality assurance within the database, only those swans that are marked in some way, either tagged, banded or both tagged and banded, are included in the database. Not every swan visiting the Wye Marsh on a yearly basis is marked, as there were only 89 marked birds by December 31 st, It is estimated that a further 26 swans visit the marsh and are unmarked. These unmarked swans still represent a large portion of the Wye Marsh population but cannot be included in the database because of the ambiguity and lack of information on these particular swans. The database does include captive pairs, but to improve quality within the results these captive pairs are not included, except in the nesting productivity section. Therefore the results from the database do not completely represent the total population of Trumpeter Swans visiting the Wye Marsh. For example, if a tagged swan is caught for treatment of lead poisoning and dies during this treatment, this swan is included in the database because there is sufficient information about the swan. If an unmarked swan is similarly caught for lead poisoning treatment and dies it cannot be included in the database because we do not know where the swan came from, how old it is and so on. 6.2 Database Creation The creation of the database is the major task of the project. This Microsoft Access Database is intended to hold all available information or every Trumpeter Swan that has been documented at the Wye Marsh at least once. The database will allow users to obtain and compile data much easier and faster and is to be used as an alternative to paper records. Because there will constantly be additional new data, there is a need to maintain the database to keep information up to date and accurate. Appendix B contains a partial copy of the database to outline the organization and provide an example. The headings of the database are as follows: Tag number, the wing(s) tagged, previous tag number Status (alive or dead), cause of death Wye Marsh bird (yes or no) Band number, the leg the band is on Name of the bird Sex Year born, year died, life span Location of birth Mother, father, sibling(s), mate Total eggs laid, total eggs hatched, total cygnets fledged Territory Medical attention/treatment (yes or no), location of treatment, type of treatment, cost of treatment Comments 6.3 Tagging and Banding An important tool in the reintroduction program is a tagging and banding program. Every effort is taken by those involved in the reintroduction program to tag and band as many swans as possible for easier monitoring of individual swans. Feed is used to lure swans into a large trap with a closing mechanism for capture. Licensed banders then catch the swans and attach two yellow wing tags, one on each wing, and a leg band (Figure 6). In addition males receive a band on the right leg and females on the left. The tagging process generally takes place in the fall after the cygnets have fledged and family groups can be caught together. The three black digits on the wing tag correspond to the last three digits on the leg band, as wing tags are occasionally lost and the leg band can identify the bird. These yellow wing tags (Figure 7) are large enough to be read by the human eye if the swan is within about 10 metres. If the swan is further away, binoculars or viewing scopes can be used to identify them. Photographs by: Marg Killing (left) and Nick Bartok (right) (Figures 6 and 7 - Tagging and Result) 6.4 Monitoring / Data Collection Collection and monitoring of data have been time consuming and difficult. Information was kept on paper and filed away since It was not until 1998 that limited information was stored in a Microsoft Excel file and now al
Recommended
View more...
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks
SAVE OUR EARTH

We need your sign to support Project to invent "SMART AND CONTROLLABLE REFLECTIVE BALLOONS" to cover the Sun and Save Our Earth.

More details...

Sign Now!

We are very appreciated for your Prompt Action!

x