Article by Stan Gray, Ogeechee Audubon
Photo by Pam Smith, Ogeechee Audubon
The Rusty Blackbird (Euphagus carolinus) has been undergoing one of the most profound chronic long-term and acute short-term declines of any North American bird species. This is the conclusion of the International Rusty Blackbird Working Group, a group of biologists, conservationists, and other professionals, formed in 2005 and dedicated to researching and reversing this decline. Estimates based on community science projects place the total population loss since the 1960’s at 85 to 95 percent. Despite extensive recent studies, the causes of this decline are still somewhat speculative, and point to no one factor. However, one of the key contributors appears to be the dramatic loss of wooded wetlands on southeastern wintering grounds.
The area just north and west of Savannah still contains numerous patches of intact wooded freshwater wetlands, although in many cases under increasing pressures from population growth. One such location is the 254-acre campus of the Savannah Christian Preparatory School (SCPS). Apart from the school buildings and athletic facilities, the campus is composed of and surrounded by an expansive wetlands complex.
In 2011, returning to SCPS for a mid-afternoon Great Backyard Bird Count after having been introduced to the location on the most recent Christmas Bird Count, Ogeechee Audubon Society (OAS) member Stan Gray encountered a sizable flock of Rusty Blackbirds, larger than from any other recent local reports. Several subsequent visits gave indication that this was indeed a special wintering spot for the blackbirds. Alerting other OAS birders about the phenomenon, visits and recorded observations grew over the next several years. A high count of 395 birds was recorded in December 2015. Birders visited at various times of the day, but one interesting pattern became apparent: the highest counts were being recorded in late afternoon, and that coincided with the birds emerging from the wetlands to congregate on the school grounds proper, in large lawn areas, or in and around an old grove of pecan trees.
Armed with a growing body of observational data, Gray uncovered a doctoral dissertation written in 2013 by University of Georgia graduate student Patricia Newell (see http://rustyblackbird.org/wp-content/uploads/Newell2013RUBLDissertation.pdf.) The dissertation focused on the winter ecology of the Rusty Blackbird. In it, Newell summarized that a suburban landscape composed of a patchwork mosaic of forested wetlands, grassy expanses, and pecan groves seemed to provide the blackbirds with the best resources for wintering. She had independently noted many of the same behavioral observations that the birders of Ogeechee Audubon were seeing at SCPS. OAS birders were observing Rusty Blackbirds at other nearby wetlands, but never in numbers approaching the sizable flocks encountered regularly at SCPS. When observations were made in early-mid mornings (the typical period when birders take to the field), counts in single digits, often just one or two birds, were recorded. Even at SCPS, morning counts yielded low numbers. Other than a “sentinel” bird perched high above the wetland floor, the remainder of the flock foraged deep within the forested wetland, barely if at all detectable as they rummaged through leaf litter for aquatic invertebrates. Access to these wetland foraging areas is often poor at best, the dark rusty blackish birds disguise quite well, and counts have probably been seriously underestimated.
In 2019, SCPS received funding to install a new main entrance gate, which would enhance the physical security of this private school. Although it has always been private, access to the campus had not been tightly controlled, especially on weekends. OAS members had come to be recognized by school officials, and birders frequented the campus. The new gate changed the issue of accessibility, and with it a fear that birders would no longer be able to monitor the status of the Rusties (and the multitude of other bird species inhabiting the diverse natural landscape of the campus).
A meeting ensued in the summer of 2019 between school officials and a committee from OAS led by President Leslie Weichsel, the importance of the campus as a vital wintering habitat for Rusty Blackbirds was explained, and a cooperative agreement was reached allowing OAS to field a dedicated team of birders having access (otherwise restricted) to the campus at regularly scheduled, pre-announced times. In addition to Rusty Blackbird surveys, the team was also granted permission to perform comprehensive surveys of the entire 250+ acre campus periodically throughout the year. The data resulting from all this survey work would be shared with SCPS officials (and posted on eBird) in support of future funding initiatives leading towards enhancement of the natural resources of the property.
Monitoring the 2019 fall migration of Rusties and their impending approach, the first OAS team survey was conducted November 3. No blackbirds were sighted that day, but the next survey on November 10 yielded 28, the first recorded seasonal eBird sighting within the surrounding 200+ miles. From then through March 22, 2020, a total of 18 surveys were conducted (all on Sunday afternoons when the campus is least active), essentially one per week. Consistent with previous years, the highest count occurred in mid-December, 138 birds. Numbers varied somewhat from week to week, but typically 60-90 birds frequented the grounds. Significant movement out of the area, presumably back towards the breeding grounds in northern Canada and Alaska began the week of March 2, and the last four birds were spotted March 22; one week later none remained.
The OAS survey team consists of a core group of five birders, joined frequently by several other Society members. Many photos were taken throughout this first survey period for documentation and posting on eBird (several of which are included herein). Over the course of the period, skills in identification improved immensely for all through intense observations, especially when mixed foraging flocks of Rusties, Common Grackles, Brown-headed Cowbirds, and Red-winged Blackbirds would commingle. Team member and author Diana Churchill published a full-page article in the November 26, 2019 issue of the Savannah Morning News informing the public of the OAS survey initiative at SCPS. Key school officials have become increasingly engaged and supportive of the effort, and much potential exists to use it in student environmental education programs or projects in the future. Surveys will re-commence in early November, and although the schedule or frequency has not been finalized, OAS plans to take advantage of the extensive baseline data created this past winter to do monitor changes in population dynamics annually. Short- and long-term survey results at this site will hopefully help inform the extensive research being conducted to reverse the decline of this intriguing, yet highly vulnerable blackbird species.
[Note: the survey team has recorded detailed observational data via eBird on each sighting of Rusty Blackbirds at SCPS. To view a discussion of these observed behavioral patterns, the reader is invited to explore the eBird Species Map for Rusty Blackbird, then enter Savannah Christian Preparatory School for location. By clicking on the point designator for “hotspot,” all reports since 2011 can be accessed. Additionally, the aerial photography demonstrates the patchwork mosaic of wetlands and other supporting manmade features, ie. grassy expanses and pecan groves, on site.]