The data collected from this study would be published in peer-reviewed scientific journals; thus, would provide a scientifically credible basis for supporting decisions made by management agencies. Further, our collaborative efforts with a concurrent apple snail study (Darby et al) will help ensure that the results of this study fit within a broader context of understanding habitat characteristics and associations of a suite of species using wet prairie and slough habitats.

Collaborators: Dr. Dana C. Bryan, Chief, Division of Recreation & Parks, Bureau of Natural & Cultural Resources, Department of Environmental Protection, Florida

Clients: U. S. Geological Survey, South Florida Ecosystem Initiative scientists, U.S. Army Corps of Engineers, South Florida Water Management District will use results of this research. It is expected that the information provided by this project will be used by management agencies in South Florida to implement and refine hydrologic restoration strategies.

B. WORK PLAN

Title of Task 1: Habitat associations
Task Funding: PBS
Task Leaders: Robert Bennetts, Phil Darby, Deborah Jansen
Phone: 352-378-8181
FAX: 352-378-4956
Task Status (proposed or active): proposed
Task priority: high
Budget and Time Frame for Task 1:
Task Personnel: 1 graduate student, 1 field tech

Task Summary and Objectives: The objective of this task is to determine the characteristics of habitats used by the limpkins in the Everglades. We would use three methods to evaluate habitat associations, which would be complimentary at different scales of resolution. Understanding these associations would assist in interpretation of any performance measure based on abundance of limpkins. However, it is our contention that a habitat-based performance measure(s) might be more effective in the long term, both in feasibility and cost of sampling and because habitat is the component of life history to which management can be applied.

1. Use distance sampling along airboat transects, stratified by major plant communities to establish association with these communities.
2. Equip 20 birds in each of two years with VHS radio transmitters and determine their location relative to habitat features at regular intervals.
3. Use a systematic grid-point sampling concurrent with the radio telemetry. This sampling would be used to estimate percentage of the area occupied (see below), but would also to provide a basis of habitat availability for analysis of the radio-telemetry data. Thus, at each point we would record the vegetation characteristics and water depth in addition to any detection of limpkins.
4. Collaborate with apple snail project to determine relationships between vegetation characteristics, apple snails densities, hydrology of habitats selected by limpkins within the wet prairie/slough habitat types.

Title of Task 2: Performance measure feasibility
Task Funding: PBS
Task Leaders: Robert Bennetts
Phone: 352-378-8181
FAX: 352-378-4956
Task Status (proposed or active): proposed
Task priority: high
Budget and Time Frame for Task 2:
Task Personnel: 1 graduate student, 1 field tech

Task Summary and Objectives: There are several potential performance measures that could be derived from monitoring limpkins, none of which have been attempted for this species. In this study, we would attempt and evaluate potential performance measures for feasibility, practicality, effectiveness, and cost. Based on these assessments, we would compare and contrast the strengths and weaknesses of potential performance measures as indicators of restoration success.

Work to be undertaken during the proposal year and a description of the methods and procedures:

FY 03:

1. Conduct a preliminary evaluation of the feasibility of estimating density of limpkins using distance sampling
2. Conduct a preliminary evaluation of the feasibility of estimating the proportion of area occupied and/or proportion of territories occupied from systematic point counts.
3. Evaluate habitat data for candidate habitat-based performance measures that could be applied to a suite of fauna, including apple snails, snail kites, limpkins.
4. Compare and contrast context-specific methodologies and potential performance measures.

Title of Task 3: Life history
Task Funding: PBS
Task Leaders: Robert Bennetts, Phil Darby, Deborah Jansen
Phone: 352-378-8181
FAX: 352-378-4956
Task Status (proposed or active): proposed
Task priority: high
Budget and Time Frame for Task 3:
Task Personnel: 1 graduate student, 1 field tech

Task Summary and Objectives: There are at least two life history traits that are essential to reliably evaluate the potential for using abundance estimates of limpkins as an indicator of restoration success: (1) the migratory status of the population, and (2) the tenacity of territorial males. Without understanding the migratory status of the population any estimates of annual variation in numbers would be confounded with seasonal variation in migration. Similarly, the proportion of area and/or territories occupied could be a misleading indicator if males do not maintain territories throughout the year, or if migrant individuals exhibit courtship behavior prior to returning to northern breeding areas.

Work to be undertaken during the proposal year and a description of the methods and procedures: FY03:

1. Using radio telemetry, determine whether males hold year-round territories within the Everglades, as they do in the northern parts of their range.
2. Using radio telemetry, determine whether there is a migratory segment of the population wintering in the Everglades (particularly females, which are known to leave their breeding sites during winter). This will require a series of flights over their known northern range during the breeding season. However, determination of whether there is a migratory component of the wintering population will not require locating all birds that have left their wintering areas, only some of them. This would also be done in collaboration with other studies using radio telemetry to increase our coverage. Satellite transmitters might be much more effective for assessing migration status of all radio-tagged birds, but are much more costly, and would be less effective for achieving our habitat assessment objectives. Given that our objective is only to determine if there is a migratory segment, we believe that VHS radios will suffice.