PENNSYLVANIA GAME COMMISSION BUREAU OF WILDLIFE MANAGEMENT PROJECT ANNUAL JOB REPORT PROJECT CODE NO.: 06750 TITLE: Wildlife Diversity Research/Management JOB CODE NO.: 70004 TITLE: Colonial Nesting Bird Study PERIOD COVERED: 1 January 2012 to 31 December 2012 COOPERATING AGENCIES AND ORGANIZATIONS: Pennsylvania Department of Conservation and Natural Resources; East Stroudsburg University; U.S. Department of Agriculture, Federation of Sportsmen's Clubs in York; Powdermill Avian Research Center, Audubon Pennsylvania and associated chapters, Pennsylvania Society for Ornithology; Three Rivers Birding Club, Pittsburgh; York City Parks Department; Bird Refuge of York County, York. WORK LOCATION(S): Statewide PREPARED BY: Don Detwiler IV and Patricia Barber DATE: 30 January 2013 ABSTRACT This project inventories and monitors colonial waterbird populations in Pennsylvania, while reporting on conservation initiatives. Great egret, black-crowned night- heron, and yellow-crowned night-heron are endangered in Pennsylvania. Colonial wading birds are particularly vulnerable because their nests are clustered, putting a large part of the nesting population at risk from natural and human disturbances. The annual Wade Island survey identified 185 great egret, 67 black-crowned night-heron, and 188 double-crested cormorant nests. The 5-year comprehensive state wide survey was conducted confirming 77 active colonies of great blue heron in 33 counties. It is recommended that (1) additional 2013 effort supplement the comprehensive survey, visiting sites missed in 2012; (2) support continue for conservation measures at Wade Island, Ephrata, and Kiwanis Lake colonies; and (3) efforts continue to identify and conserve yellow-crown night-herons nesting in and near Harrisburg. OBJECTIVES 1. Inventory all colonial water bird populations by monitoring breeding sites, every 5 years. 2. Survey all great egret, black-crowned night-heron, and yellow-crowned night-heron colonies and several of the largest great blue heron colonies annually. 70004 2 METHODS Volunteers, cooperators, and Pennsylvania Game Commission (PGC) biologists counted as many of the great egret, black-crowned night-heron, yellow-crowned night-heron, and great blue heron nests as possible during the 2012 breeding season. Volunteers were recruited through press releases, the PABIRDS listserve, and the PGC website; and used a standard protocol and datasheet. Counts were conducted from the ground at previously and newly identified locations. Nests were counted if they appeared to be active during the 2012 breeding season. RESULTS The Wade Island survey was conducted on 2 May 2012. Leaf out was nearly complete, making nests difficult to find and assign to species. One hundred eighty-five great egret, 67 black-crowned night-heron, and 188 double-crested cormorant nests were found during the survey (Fig. 1). Many of the black-crowned night-heron nests were either under construction or recently completed, suggesting the nesting population is larger than the nests counted. The cormorant nest count will be used to evaluate the effectiveness of the 2012 cormorant cull in June and July. Great Egret (Ardea alba; Pennsylvania [PA] Status - Endangered)— Great egrets were recorded nesting at 2 locations, Wade Island in Dauphin County and Kiwanis Lake in York County. There were 185 nests found at Wade Island and 8 found at Kiwanis Lake representing an above average year (10-year average of 160 nests). The Wade Island population increased substantially from 103 nests in 2011. The Kiwanis Lake population remained stable. Black-crowned Night-heron (Nycticorax nycticorax; PA Status – Endangered)— The black-crowned night-heron population in Pennsylvania continues to decrease. All 5 active colonies in 2012 were in urban or suburban locations in southeast counties, particularly vulnerable to human disturbances. Black-crowned night-heron nests decreased across surveyed sites by 17% in 2012 from 214 nests to 178 nests. This decline is largely a substantial decrease at the Kiwanis Lake colony, which dropped from 96 nests to 23. Coupled with the growth of the Ephrata Hospital colony (30 nests in 2011 to 83 in 2012) the state’s population distribution has seen a drastic reorganization. The majority of birds are nesting in three locations Kiwanis Lake 13%, Wade Island 37.6%, and Ephrata Hospital 46.6% (Table 1). Any disturbance, human or natural, at these sites would jeopardize the species’ persistence in the state. At Kiwanis Lake black-crowned night- heron nests decreased precipitously. This may be due to the cutting of low branches off the pine trees where the birds previously nested; this was done in the past though not for several years. The Wade Island population decreased by 25%, but last year’s late survey date confounds these results; the number of nests counted underestimated nesting pairs. The Ephrata Hospital colony is up 276% from last year (30 nests in 2011 to 83 in 2012). The Wyomissing Hills site was reestablished and hosted 8 to 12 nests in a diffuse colony. Yellow-crowned Night-heron (Nyctanassa violacea; PA Status – Endangered) 70004 3 The yellow-crowned night-heron is critically endangered in Pennsylvania with only 10 nests reported in 2012. Yellow-crowned night-herons are fairly tolerant of some human activities and readily nests in wooded settings close to human habitation, including backyards, near streams and in town near the Susquehanna River. Foraging near dusk and at night helps it co- exist with people. All of the nests found this year were in downtown Harrisburg in large sycamores that either overhang streets or backyards. The nesting sites in the historic wooded urban neighborhood in Belleview Harrisburg, Dauphin County were inactive, but should be monitored in case the herons return. There were no reports of nesting activity along Conodoquinet Creek or West Fairview, Cumberland County. Double-crested Cormorant (Phalacorax auritus; PA Status – Secure) This colonial waterbird has increased in population and nesting range throughout Northeastern United States, including Pennsylvania, in recent years (Hatch 1995, Hatch and Weseloh 1999, McWilliams and Brauning 2000, Wires and Cuthbert 2006). The first nesting during the current expansion was found at Wade Island in July 1996 (McConaughy 1996); it was not identified in the first Pennsylvania Breeding Bird Atlas or previously (Brauning 1992, McWilliams and Brauning 2000). This species has steadily increased in the region since the 19th century except for the pesticide era from which it continues to recover and gain ground as a nesting species and passage migrant. In 2012, the number of double-crested cormorant nests at Wade Island increased by 61, to 188 (Table 1). Cormorants may displace great egrets and black-crowned night-herons in the Wade Island colony. This substantial increase raises concern for the overall colony health. Consequently, 432 cormorants were culled during June and July by U.S. Department of Agriculture Wildlife Services personnel. Great Blue Heron Colonies Great blue heron is not listed as a Species of Greatest Conservation Need, but it is especially vulnerable to disturbance like other colonially nesting waterbirds. Because of their conservation value, larger colonies are tracked annually. A comprehensive statewide survey of great blue heron colonies was conducted in 2012; 1,312 nests were found in 60 colonies in 33 counties (Table 1). Additional locations missed in 2012 will be visited in 2013 to complete the survey. The Barrows colony, a Pennsylvania Audubon Important Bird Area, continues to be the largest great blue heron nesting site in Pennsylvania. In 2011 there were 298 nests, an 11.6% increase. In 2012 the population decreased slightly to 276 nests, however it still constitutes 24.4% of the state population. The Barrows colony reached a peak of 441 nests in 1999, declining and leveling out in 2009 and 2010 to the present level. Web pages for colonial birds are hosted on the PGC’s website and include species specific pages for great egret, black-crowned night-heron and yellow-crowned night-heron, as well as general information on herons and wade island. Between 1 May and 31 December 2012 these pages were viewed over 5,000 times. The target audience for these pages is educators, school children and adults interested in wildlife and conservation. 70004 4 RECOMMENDATIONS 1. Monitor Wade Island colony and improve protection with additional restricted area signs. Limit annual survey to less than 2 hours to minimizing disturbance; and continue an adaptive management approach for endangered species protection. 2. In 2013 survey all colonies of black-crowned night-heron, yellow-crowned night- heron, great egret and those great blue heron colonies not covered in 2012. Continue engaging volunteers in the surveys. For colonies that are easily accessible and with most nests in conifers, additional nest counts in early to mid June could be useful. 3. Educate private landowners hosting colonial waterbird colonies of the values of the birds and provide them with guidelines for colony protection. Proactively involve the Regional Wildlife Diversity Biologists with these colonies and the landowners when possible. More information should be provided in PGC educational materials, including website pages, to educate the public about colonial waterbird colony protection. 4. Maximize protection of nesting black-crowned night-herons at Kiwanis Lake, by working with Audubon Pennsylvania and the York City Parks Department, and obtain