ANNUAL REPORT. Avian Research Subsection Wildlife Research Section Fish and Wildlife Research Institute

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1 ANNUAL REPORT Avian Research Subsection Wildlife Research Section Fish and Wildlife Research Institute Project Number: Project Title: Project Investigator: Project Manager: American Oystercatcher Monitoring Janell M. Brush, Fish and Wildlife Research Institute, Wildlife Research Lab, 1105 SW Williston Road, Gainesville, FL Amy Schwarzer, Fish and Wildlife Research Institute, Wildlife Research Lab, 1105 SW Williston Road, Gainesville, FL Fiscal Year Covered: FY Research Assistants: Carolyn Enloe, Bobbi Carpenter, and Jeanne Baker, Fish and Wildlife Research Institute, Wildlife Research Lab, 1105 SW Williston Road, Gainesville, FL Raya Pruner, Marvin Friel, and Tyler Brown, Florida Park Service, District 1, Department of Environmental Protection, 4260 State Park Lane, Panama City, FL Doris & Pat Leary, 1291 S. 3 rd St, Fernandina Beach, FL Prepared By: Janell M. Brush, Amy Schwarzer Date Prepared: October 10, 2013

2 Banded American Oystercatcher chick with adults on the Tolomato River in Northeast Florida Abstract: The American Oystercatcher (Haematopus palliates) (AMOY) is listed as threatened in Florida, due to its small population size and restricted range. The breeding Florida AMOY population may make up to 24% of the entire breeding population. AMOY in Florida had low reproductive success this nesting season. Only 22% of AMOY nests that were monitored hatched. The majority of nests in the panhandle failed due to coyote predation, while nests in Northeast Florida and Big Bend regions mostly failed due to overwash. Of the nests monitored, productivity was 0.23 fledged chicks per breeding pair and 0.18 fledged chicks per active nest. Analysis of nesting habitat selection data and mark-recapture data is on-going. INTRODUCTION The American oystercatcher (Haematopus palliates, AMOY) is a species of high conservation concern due to its small population, its declining trend and widespread degradation of its coastal habitat (Brown et al. 2001). The species is listed as threatened in Florida (FWC 2011). The AMOY is one of the few birds that feed primarily on marine bivalves, and therefore reside in coastal areas that support intertidal shellfish beds. AMOY require extensive beaches and mudflats for their nesting, roosting, and feeding activities (Nol and Humphries 1994, Below 1996). Nesting substrates include undeveloped barrier beaches, sandbars, sand spits at inlets, shell rakes, salt marsh islands, and oyster reefs. However, AMOY have been observed using non-traditional nesting substrates such as spoil islands covered by Australian pine (Casuarina equisetifolia) (Toland 1992), salt marshes (Shields and Parnell 1990), and gravel-covered rooftops (Douglass et al. 2001). Hunter et al. (2006) identified the AMOY as a vulnerable species that will continue to decline without conservation measures to protect nesting habitat. AMOY productivity can be impacted by disturbance from recreational boaters and fishermen, adverse weather conditions, pressure wakes from large ships and boats, and predation. Entanglement in fishing gear and exposure of adults or breeding areas to oil spills are also concerns, as is the threat of global climate change and sea level rise (FWC 2011).

3 Cox et al. (1994) identified three population centers for AMOY along the Florida Gulf coast, and a sparse but continuous distribution along the Atlantic coastline. This statewide analysis concluded that the habitat base required for long-term stability of AMOY in Florida was insufficient (Cox et al. 1994). The Florida Fish and Wildlife Conservation Commission (FWC) conducted a statewide survey in 2001 of nesting AMOY (referred to as historical survey ). The goal of the survey was to determine the number of nesting pairs of AMOY in Florida. Key objectives were to determine appropriate survey methods, document nesting distribution and identify important nesting areas. The survey covered potential nesting habitats along the entire Florida coast. Three of the areas identified as important nesting areas were the Panhandle, Big Bend and Northeast Florida. AMOY are long lived and reproductive rates tend to be highly variable but generally low (Nol and Humphrey 1994, Davis et al. 2001). A species with low productivity and high adult survival avoids rapid population swings, but has limited ability to recover quickly from population declines (Schulte 2010). Revisiting some of these nesting areas will allow us to document if they are still occupied by nesting AMOY and measure nesting productivity. Results from this study will be useful in establishing future management objectives and priorities for nesting AMOY. Data resulting from our study will determine nesting site fidelity and habitat variables that contribute to a site being occupied. The AMOY nesting locations will be geo-referenced with physical beach/oyster bar characteristics and anthropogenic disturbance levels, and will be useful in coastal planning and management activities. Results will enable the FWC to collaborate with other state and federal agencies working on the conservation of AMOY to devise strategies for managing coastal habitats and associated shorebird species. OBJECTIVES 1. Identify current nesting locations within survey area. 2. Determine productivity of monitored nests. 3. Continue banding program for adult and juvenile AMOY 4. Monitor marked birds to determine breeding site fidelity, distribution and movement patterns of AMOY. METHODS Study Area The study area included four areas identified as having significant AMOY breeding populations: Cedar Key and the Florida Barge Canal in the Big Bend, and the Tolomato and Matanzas Rivers in the Northeast. In addition, Florida State Parks in the Central Panhandle were also monitored by DEP partners.

4 Figure 1. The study areas for nesting American oystercatchers. Nest Monitoring. Study areas were surveyed for nesting AMOY every 7-14 days. DEP State parks in the Central Panhandle were surveyed weekly by park staff. We used pre-established shorebird survey routes (FWC shorebird database). The FWC Beach Nesting Bird Protocol was followed ( Additional protocol included: Use pre-established survey routes for repeat surveys. Record the latitude/longitude for every nest found. Document potential sources of disturbance and disturbance events and document predator activity (via tracks and direct observation). Determine nest status: active, failed (record reason for failure if known), successful (producing at least one chick), abandoned. Determine chick survival (to fledgling stage). Record habitat use of precocial chicks (list options). When nesting has been completed, conduct habitat sampling. Banding. In other states, banded AMOY are used to verify high nesting site fidelity (Schulte et al. 2010). In order to document fidelity, movement during the breeding season, and juvenile dispersal we banded both adult and juvenile AMOY. We trapped at nesting locations that were monitored consistently throughout the season. We trapped adults using a box trap placed over the nest. In order to avoid damage to eggs during trapping activities, we temporarily removed eggs from the nest bowl and replaced them with decoy eggs. Eggs were kept in a cool, shaded location during trapping. We captured juvenile AMOY using a large hand net. Juveniles were trapped between days old. Birds were banded according to the cooperative banding protocol adopted by all researchers in the AMOY Working Group and approved by the Bird Banding Lab. Under this scheme, birds are marked with two identical color bands engraved with

5 unique 2-digit codes, as well as, a silver USFWS band. Birds in Florida are banded using red bands with engraved white numeric codes. Resighting. The mark-resight survey methodology followed a robust design protocol. A repeated-sampling survey protocol (Williams et al. 2001) involving 5 sampling periods was initiated following the completion of nesting. At each study area, we located concentrations of AMOY and recorded the following information: GPS location. The number of marked and unmarked individuals. 2-digit band code of banded individuals. Age of banded birds. Habitat type at the observation site. Potential sources of disturbance and disturbance events. Date and time. RESULTS Nest Monitoring FWC researchers located 51 pairs of territorial oystercatchers within the survey area. Nests at three sites were monitored more intensively in order to document breeding success and movement patterns: the Florida Barge Canal on the Nature Coast, and the Tolomato and Matanzas Rivers in the Northeast. Cedar Key was excluded from periodic monitoring due to logistical considerations. In these areas FWC researchers followed 39 pairs and 50 nests. Nesting success during the season was low (11 nests or 22% hatched). These pairs fledged a total of at least 9 chicks (productivity = 0.23 fledged chicks per pair or 0.18 fledged chicks per nest). Overwash from high spring tides, and possibly boat wakes in the case of the Tolomato and Matanzas Rivers, was responsible for the majority of lost nests. DEP staff followed an additional 20 nests and pairs in St. George and St. Joseph Peninsula State Parks. Nest success was also low (3 nests or 15% hatched). Nest loss was primarily due to predators, particularly coyote. No chicks fledged. Banding and Resighting FWC researchers and DEP partners in the Panhandle banded 7 adults and 10 chicks during the season as part of an effort to understand adult and juvenile movements. Two previously banded adults, one banded on Little Egg Island Georgia as an adult on October 25, 2010 and the second banded on the Amelia River, Florida as a chick on July 12, 2008, were found nesting on the Tolomato River. In addition, three previously banded birds, two banded at Cape Romain National Wildlife Refuge, South Carolina on July 16, 2011, and a third banded on the Amelia River, Florida as a chick on August 5, 2011, were seen paired, and in one case, copulating with other AMOY on the Matanzas River during the breeding season. Although these birds were present throughout the breeding season, nesting was not confirmed for any of these birds. During the nesting season FWC researchers resighted 38 individual banded birds a total 117 times. Nine of these individuals were likely non-breeding birds that were either migrating

6 through or residing in the study areas. Resighting results from DEP in the panhandle are not available at this time. Seven out of eight adults banded in Northeast Florida and the Big Bend during 2012 were seen during this breeding season. Five had confirmed nests and all were seen in the same locations as last year. Five out of eleven juveniles banded in Northeast Florida and the Big Bend during 2012 were also seen during winter and/or during the 2013 breeding season. DISCUSSION Nest Monitoring The AMOY had a 22% hatching success rate and produced 9 fledglings (productivity = 0.23). The documented reasons for nest failure varied. Overwash caused the majority of nest losses within the study areas covered by FWC researchers, while predation accounted for most nest losses in the Panhandle state parks. The most successful area in 2013 was the Tolomato River with productivity of 0.30, though this productivity was lower than productivity in 2012 (0.75). The Barge Canal had a productivity of 0.25, which was an increase over 2012 (0.18). The Matanzas River had no productivity, a decrease from 2012 (0.25). Disturbance was reported to be a problem at several nest locations on the Tolomato River and in the Panhandle. Management can increase nest protection measures by posting closed areas as nests are discovered or improving current posting in known nesting areas. For nest sites with documented mammalian predation, predator control programs may be critical to the success of nesting AMOY. To address overwash of nests, restoring nesting habitat through earthmoving activities and/or oyster reef restoration may be a feasible management strategy. Erosion of nesting islands and increased frequency and severity of storms is projected to increase due to climate change and sea level rise, making this an important issue to address. In addition to the AMOY nest monitoring within our study area, Florida Shorebird Alliance partners monitored other areas for nesting AMOY. A total of 198 AMOY nests were located and monitored at 46 locations statewide (Table 1). Results are preliminary and some nesting areas were covered but data have not been submitted or verified in the Florida Shorebird Database. The Tampa Bay area was completely surveyed, however a few of the most productive sites in the state such as Richard T. Paul Alafia Bank Sanctuary have not been reported for this nesting season. Next nesting season we will continue to opportunistically band breeding adults and fledglings and resight previously banded AMOY. This will allow for detailed and insightful nesting data to be obtained compared with what we can currently collect with unmarked AMOY. With marked AMOY we have more confidence in observations of nesting effort per pair of AMOY, movement patterns, site fidelity, and habitat use. We will continue banding juveniles to study juvenile dispersal and survival. Banding and Resighting Monitoring efforts by volunteers allowed FWC researchers to band two chicks on the Amelia River and one chick at Hugenot Memorial Park (HMP). The chick banded at HMP represents the first ever bird banded at this location, as well as the first chick fledged from this

7 location in many years. While banding efforts this breeding season were successful, data are currently not robust enough to conduct survival analyses. However, preliminary results suggest high site fidelity within adults. Resightings of last year s juveniles also suggest that there may be some broad scale dispersal of juveniles. FUTURE RESEARCH Banding AMOY and mark-resight surveys will continue. As we develop a long-term band resight data set we will be able to estimate apparent annual survival for adults and juveniles as well as nest site fidelity. Additional research needs include: Determine productivity on a 5-year running average. Areas with greater numbers of nesting AMOY should be monitored weekly during nesting season. Monitoring should be expanded to cover all nesting areas in order to produce more robust, statewide estimates of productivity. Identify acute population threats limiting populations (statewide and site-specific). While we currently have a qualitative understanding of the primary causes of nest loss, a systematic quantitative approach is necessary to prioritize threats and subsequently management activities. These data combined with demographic estimates derived from mark-recapture analyses as well as habitat loss models will allow us to identify critical threats. Assess impacts of various types of disturbance at different life stages (breeding, broodrearing, migration, wintering) and evaluate techniques to mitigate disturbance impacts. As the number of people living on the coast continues to grow, interactions between AMOY and humans will increase. Determining how disturbance affects AMOY will be critical for the management and conservation of AMOY. Model the impact of climate change (sea-level rise, temperature change, red tide events and change in rainfall) on the foraging habitat and nesting distribution of AMOY and model potential impacts and develop management protocols to mitigate effects of climate change. Modeling these effects will allow us to identify key areas where management activities can have the most positive impact on the AMOY population. ACKNOWLEDGMENTS We wish to thank the following groups: United States Fish and Wildlife Service (USFWS), Florida State Parks, Audubon of Florida, American Oystercatcher Working Group, Florida Shorebird Alliance, Manomet Center for Conservation Science, Lower Suwannee and Cedar Keys NWR, Ft. DeSoto County Park, and Georgia Department of Natural Resources. Funding was provided through the FWC Non-game Trust Fund. Thank you to the many individuals who continue to contribute to the success of this project, in particular thanks to: Jim Rodgers, Nancy Douglass, Alex Kropp, Julie Burford, Kristin Rogers, Patrick Leary, Doris Leary, Raya Pruner, Marvin Friel, Tyler Brown, David Hartgrove, Brad Winn, Stephen Brown, Shiloh Schulte, Ted Simon, Walt McCown, Erin Leone, Jessica Therriault, Kaitlin Deutsch, Justin Stapleton, Monique Borboen, Shelley Beville, Windy Wood, and Nicki Giordano.

8 LITERATURE CITED Baker, P., D. Bergquist and S. Baker Oyster Reef Assessment in the Suwannee River Estuary. Final Report to St. Johns River Water Management District. 35 pgs. Beck, M.B., R.D. Brumbaugh, L.Airoldi, A. Carranza, L.D. Coen, C. Crawford, O.Defeo, G.J. Edgar, B.Hancock, M. Kay, H. Lenihan, M.W. Luckenbach, C.L. Toropova, G. Zhang Shellfish Reefs at Risk: A Global Analysis of Problems and Solutions. The Nature Conservancy, Arlington VA. 52 pp. Bergquist, D.C., J. A. Hale, P. Baker and S. M. Baker Development of Ecosystem Indicators for the Suwannee River Estuary: Oyster Reef Habitat Quality along a Salinity Gradient. Estuaries and Coasts 29; Brown, S.C., B. Hickey, B. Harrington, R. Gill The U.S. Shorebird Conservation Plan, 2 nd ed. Manomet Center for Conservation Sciences, Manomet, MA. Brown, S.C., T. Simons, S. Schulte, F. Sanders, B. Winn, B. Truitt, A. Wilke, S. Johnston, S. Melvin and the American Oystercatcher Working Group A Business Plan for the American Oystercatcher: A Ten Year Plan to Secure a Keystone Coastal Species. Hand, C., Foraging Ecology of American Oystercatchers in the Cape Romain Region, South Carolina., M.S. Thesis, Clemson University, Clemson, SC, USA. Nol, E. and R. C. Humphrey American Oystercatcher (Haematopus palliatus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: doi: /bna.82 Thibault, J Breeding and Foraging Ecology of American Oystercatchers in the Cape Romain Region, South Carolina., M.S. Thesis, Clemson University, Clemson, SC, USA. Williams, B.K., Nichols, J.D., Conroy, M.J Analysis and Management of Animal Populations. 817 pp. Academic Press. Florida Fish and Wildlife Conservation Commission Florida s Wildlife Legacy Initiative. Florida s Comprehensive Wildlife Conservation Strategy. Tallahassee, FL, USA. Schulte, S., S. Brown, and the American Oystercatcher Working Group Version 1.0. American Oystercatcher Conservation Plan for the United States Atlantic and Gulf Coasts.

9 Table 1. Statewide AMOY nest site locations for 2013, number of nests monitored, nest site success (hatched at least one chick), minimum number of chicks hatched and minimum number of fledged birds. FWC researchers and DEP biologists monitored (gray). Some sites had more than one group monitoring them. The sites that are not highlighted were monitored by members of the Florida Shorebird Alliance. The data was reported in the Florida Shorebird Database and some sites have not been reported. Site Name Total # nests Successful Chicks Hatched # Fledged Amelia Island SP 0 NA Amelia River 2 Y 2 2 Anclote Key 2 U U U Apollo Beach 1 Y U U Bird Island (Apalachicola) 1 U U U Black Hammock 0 NA Caldesi Island 2 Y 1 1 Clearwater ICW 1 U U U Corrigan's Reef 1 U U U Derrick Key 2 U U U Dog Island (Cedar Key) 0 NA Dog Island (Panhandle) 5 N 0 0 Egmont Key 3 Y 2 2 Fantasy Island 2 U U U FL Barge Canal 16 Y 12 4 Flagg Island 7 Y 1 1 Ft DeSoto County Park 1 N 0 0 Gomez Key (Cedar Key) 3 U U U Honeymoon Island 3 Y 14 1 Hugenot Memorial Park 1 Y 1 1 Indian River 2 Y 3 U Lanark Reef 11 Y 1 1 Little Estero Island CWA 1 N 0 0 Little St. George Island 3 N 0 0 Little Talbot Island SP 3 N 0 0 Madeira Beach 1 U U U Martin County Spoil 1 U U U Matanzas River 2 N 0 0 McClamory Key 0 NA Old St. George Causeway 3 Y 4 2 Phipp's Preserve 3 U U U Rattlesnake Key 1 U U U Robert's Bay 1 U U U Rookery Island 1 N 0 0 Sand Keys (Clearwater) 3 Y 1 U Shell Key 1 U U U Snook Island 2 U U U St. George Island 19 Y 6 0 St. Joseph Peninsula SP 1 Y 3 0 Sunken Islands 4 Y 1 U Tampa Bay Spoil Island 2D 39 Y 2 U Tampa Bay Spoil Island 3D 5 Y 1 1 Teco Fish Hook Island 1 Y 1 1 Three Rooker Bar 1 Y 2 U Tolomato River 35 Y 9 6 Tyndall Air Force Base 1 N 0 0 TOTALS