Project Title: Avian Ecology of the Greater Everglades (Rosette Spoonbill and Limpkins)

Project Start Date: 2003 Project End Date: 2005

Web Sites: http://cars.er.usgs.gov/sofla/Spoonbills/spoonbills.html

Location (Subregions, Counties, Park or Refuge): Florida Bay (Monroe County)

Funding Source: USGS's Greater Everglades Science Initiative (PBS)

Principal Investigator(s): Jerome J. Lorenz, Robert E. Bennetts

Project Personnel: Jerome J. Lorenz, Robert E. Bennetts

Supporting Organizations: Audubon of Florida

Associated / Linked Projects:

Overview & Objective(s): This project is designed to evaluate the effect of hydrologic restoration on the nesting distribution and success of Roseate Spoonbills (Ajaia ajaia) in Florida Bay and surrounding mangrove estuarine habitats. This project is further designed to test hypotheses about the causal mechanisms of observed changes. The primary objectives are to (1) quantify the changes in spatial distribution and success of nesting spoonbills relative to hydrologic patterns, (2) use annual variation in hydrology in quasi-experimental context to test hypotheses about the causal mechanisms for observed changes, (3) establish a science-based criteria for nesting distribution and success to be used as a performance measure for hydrologic restoration, and (4) estimate demographic parameters.

Status: Funds were insufficient and arrived too late to conduct a full scale sampling effort during FY2003; thus we conducted a pilot investigation to refine our methods and to establish protocols. Preliminary surveys were conducted at all colonies in Florida Bay. A sample of nests (n=116) were monitored, and we banded a total of 25 chicks. An additional 162 chicks were banded at Tampa Bay for: (1) comparison to Florida Bay, (2) to establish whether linkages exist between Florida and Tampa Bay populations, and (3) to refine our marking protocols. Insufficient funds were available to conduct any work on Limpkins at this time.

Recent & Planned Products: 1st Annual Report (planned, 9/03); Presentation (USFWS, June 2003); Presentation (C-111, PDT Meeting, March 2003); Presentation (Geer Conference, April 2003); Avian Workshop Session (March 2003)

Relevance to Greater Everglades Restoration Information Needs: The re-establishment of healthy wading bird populations in the Everglades system has been at the forefront of restoration goals since its inception. As such the project elements listed below directly contribute to USGS Science Plan: Goal 1A, SO3, SO4; Goal; 2A - SG1 SG4; Goal 2B - SG1 SG3, SG4, SG5 and DOI Science Plan Chapter 3I, 4A.1, and 4C.

• The Roseate Spoonbill has been frequently identified as one of the key indicator species for restoration of the estuarine system.
• Annual variation in spoonbill response to hydrology will be to test hypotheses about the causal of observed changes
• The conceptual model developed on this project would be formalized and made available to management agencies through a collaborative effort with the ATLSS modeling
• This model could be used by management agencies as an exploratory tool to evaluate alternative management actions and scenarios.

Key Findings:

• Roseate Spoonbill nesting effort in Florida Bay during 2003 was the lowest recorded since 1970.
• The nesting effort in the Northeastern sub-region of Florida Bay (associated with the C-111 Basin) generally failed; whereas the other 3 active subregions were successful.
• In contrast to the low effort in Florida Bay, nesting effort in Tampa Bay was relatively high and successful. It is not known to what extent this represents a shift in distribution from Florida Bay. Our full scale efforts would be capable of assessing this hypothesis.
• Pilot efforts indicated a high probability of successfully being able to estimate numerical and behavioral responses (i.e., shifts in distribution and changes in nesting effort and success) to hydrologic conditions.