2001 Monitoring Reports 
Section II. Bird Survey
Introduction
Bird surveys conducted over many years help researchers monitor trends in bird populations. These intensive, long-term studies lend insight about different species' behavior and their preferred habitats. Changes in the environment, either natural or human induced may be reflected in changes of population or species numbers.
Survey Methods
Ten stations were selected to survey the breeding birds (Figure 1). The stations are approximately 900 feet apart, within the Coffee Creek Watershed Preserve between the railroad grade (now Rail Road) on the north and the Indiana Toll Road on the south. Six of the ten stations (1, 2, 3, 4, 9 and 10) are located in wooded portions of the corridor. The stations were selected (1) to avoid overlap in potential territories and thus avoid censusing the same birds more than once and (2) to allow sampling at each of the various habitat types present within the corridor. All individuals seen and/or heard at a station within a 5-minute sampling period were recorded, except for the survey in 1997, when 10-minute intervals per station were used.
Station Descriptions
Surveys were conducted on June 10, June 16 and August 15, 2001 (on August 4, 1997, June 21,1998, June 27, 1999, and August 3, 2000 in previous years). The average temperature ranged between 70 and 80 degrees. The range of time, average temperature, weather, number of minutes spent at each station, and the number of birds and species found each year are detailed in Table 1 and illustrated in Figure 13 under Results and Discussion. Descriptions of sampling stations and the bird species recorded at each station are presented in Appendices 18-20.
| Date | Time | Avg. Temp. | Weather | Min. per Station | # Birds (# species), per Station |
| 8/4/97 | 6:00-10:40 am | N/A | N/A | 10 min. | 98 (29) |
| 6/21/98 | 5:10-8:15 am | 75˚ F | Winds calm, sky clear/partly cloudy | 5 min. | 194 (36) |
| 6/27/99 | 6:00-8:30 am | 75 ˚ F | Winds calm, sky partly cloudy/overcast | 5 min. | 264 (38) |
| 8/3/00 | 7:30-9:40 am | 72 ˚ F | Winds moderate, sky mostly sunny | 5 min | 162 (37) |
| 6/10/01 | 7:57-10:30 am | 75-80º F | Winds light, sky mostly clear | 5 min | 115 (23) |
| 6/16/01 | 5:35-8:15 am | 70-75º F | Winds light, sky mostly clear | 5 min | 151 (26) |
| 8/15/01 | 6:10-8:30 am | 70-75º F | Winds light, sky mostly clear | 5 min | 218 (32) |
Table 1. Amount of time spent, weather conditions, and number of birds found at each sampling station during the 1997, 1998, 1999, 2000, and 2001 bird sampling events.
Station 1
Station 1 is the southern-most station, located within a mature beach-maple forest on a steep ridge adjacent to the floodplain on the north side of Coffee Creek. Minimal understory is present at this station as compared to elsewhere in the woodland. On June 10, 2001, four species were observed with seven individuals and two individuals of one species were observed flying over. On June 16, 2001, 13 individuals of five species were observed at this station. On August 15, 2001, six species and 11 individuals were observed.
Station 2
Station 2 is located in a floodplain east of the creek. Vegetation in this open, wooded area includes tulip tree and walnut trees with an understory of wild ginger, beggar’s ticks, violets, wild onion, and rue anemone. On June 10, 2001, a total of five species and 16 individuals were observed and ten individuals of one species were observed flying over. On June 16, 2001, three species and five individuals were observed. On August 15, 2001, five species and five individuals were observed.
Station 3
Station 3 is adjacent to the east side of the creek at the location of the gas pipeline crossing. An approximately 200 foot wide area at the pipeline crossing was cleared of all woody vegetation. Both north and south of the pipeline crossing is wooded. On June 10, 2001, six species and 11 individuals were observed as well as one individual of one species flying over. On June 16, 2001, six species and six individuals were observed. On August 15, 2001, seven species and 10 individuals were observed.
Station 4
Station 4 is in a wooded area on the east side of the creek near an old meander of Coffee Creek. Vegetation includes maple, basswood, and beech trees, with an understory of wild geranium, false solomon seal, trillium, mayapple and blue cohosh. On June 10, 2001, five species and six individuals were observed. On June 16, 2001, five species and six individuals were observed. On August 15, 2001, four species and five individuals were seen.
Station 5
Station 5 is in a clearing in the floodplain on the east side of the creek. Vegetation includes cottonwood, elm, and willow trees. The understory is vegetated with jewelweed, blackberry, ragweed, bidens, smartweed, and goldenrod. On June 10, 2001, seven species and 13 individuals were noted. On June 16, 2001, seven species and nine individuals were observed. On August 15, 2001, 10 species and 21 individuals were seen.
Station 6
Station 6 is next to the "Tuning Fork" area on the west side of the western-most bend of Coffee Creek. The creek banks are vegetated with various trees and shrubs. Old-field species and early pioneer woody species dominated the area in 1997, prior to prairie planting and included ash, black walnut, grape, poison ivy and smooth brome. On June 10, 2001, five species and nine individuals were observed. On June 16, 2001, 12 species and 17 individuals were seen. On August 15, 2001, 12 species and 18 individuals were observed.
Station 7
Station 7 is located in an open field on the west side of Coffee Creek adjacent to Phillip’s Pond, which is currently surrounded by some cattails and emergent vegetation. In 1997, previous to the hydrologic dredging, this pond was a cattail marsh, filled in with sediment over the years. The surrounding fields were seeded to prairie in 1998, and previously were old-field. A small grove of trees, including hickory (Carya sp.) and oak, border the south and east side of this pond. On June 10, 2001, five species and 15 individuals were observed and five individuals of one species were seen flying over. On June 16, 2001, nine species and 25 individuals were observed. On August 15, 2001, 10 species and 109 individuals were observed and 50 individuals of one species were observed flying over.
Station 8
Station 8 is located adjacent to a walnut grove in an old field on the west side of Coffee Creek. Two old barns were near this station, until 2000, when one barn was razed due to its condition. On June 10, 2001, 13 species and 24 individuals were observed. Additionally, one individual of one species and six individuals of a second species were observed flying over. On June 16, 2001, 11 species and 36 individuals were observed and 18 individuals of one species were observed flying over. On August 15, 2001, six species and 12 individuals were observed.
Station 9
Station 9 is located on the east side of Coffee Creek, north of County Road 1050 North, at the forest edge. The dense understory includes nettles, ragweed, and bidens. On June 10, 2001, three species and 15 individuals were observed and 12 individuals of one species were observed flying over. On June 16, 2001, nine species and 13 individuals were observed. Additionally, three individuals of one species and two individuals of a second species were observed flying over. On August 15, 2001, five species and 25 individuals were observed. Fifteen individuals of one species and 7 individuals of a second species were observed flying over.
Station 10
Station 10 is located on the east side of Coffee Creek, at the northern property boundary. This area is vegetated with ragweed and thistle. Access along the abandoned railroad grade has been constructed via an extension of County Road 125 East, which is now called Rail Rd. On June 10, 2001, two species and four individuals were observed. On June 16, 2001, five species and 30 individuals were observed and 22 individuals of one species were observed flying over. On August 15, 2001, four species and five individuals were observed. In addition, one individual of one species and two individuals of a second species were observed flying over.
Results and Discussion
Between 1997 and 2001, 62 species of birds have been recorded, not including the flyover species. Two additional species, Tufted Titmouse (Parus bicolor) and Red-eyed Vireo (Vireo olivaceus) were observed between stations but never recorded at a station. Appendix 18 identifies the species and number of individuals found during each site visit in 2001. A summary of all five years is presented in Appendix 19.Figure 13 depicts the number of species recorded during the site visits in 2001. Figure 14 shows the total number of species observed in each year during the surveys from 1997 to 2001.
Figure 13. The number of species per
station and the total species per site visit found at the
Coffee Creek Watershed Preserve for the 2001 sampling
dates.
Figure 14: The total number of
species observed per year at the
Coffee Creek Watershed
Preserve for the 1997- 2001 sampling dates.
After five years of bird surveys, the observed avian diversity
of 62 species is still below what we might expect for a site
the size of the Coffee Creek Watershed Preserve. Based on the
habitat types present at Coffee Creek, we could probably add
40+ species to the list that have a high likelihood of using
the corridor for some part of the year. Many of these species
would usually only be encountered during spring and fall
migrations. One reason we have not seen these birds may be that
the surveys have not sufficiently sampled the site during these
time periods. However, even though the observed overall avian
diversity is lower than might be expected, the breeding bird
diversity of 40 species represents a good sampling of the
breeding birds that we would expect in Northwest Indiana.
The majority of the bird species observed within the corridor are common inhabitants of wooded edges. Examples of these birds include Red-bellied Woodpecker, Northern Flicker, Blue Jay, Tufted Titmouse, Black-capped Chickadee, White-breasted Nuthatch, House Wren, American Robin, Gray Catbird, Red-eyed Vireo, Indigo Bunting, and Eastern Towhee. Birds observed which prefer open grassland habitat with little tree or shrub cover include Killdeer, Northern Bobwhite, Dickcissel, and Grasshopper Sparrow. The Eastern Meadowlark was also seen in the open grass area, although not directly counted at one of the stations. A third distinctive habitat type present within the corridor is the aquatic habitat associated with the creek and wetland. Birds observed in this habitat include Mallard, Marsh Wren, Yellow Warbler, Common Yellowthroat, Red-winged Blackbird, and Green Heron.
There are several species of note that have been found on the site. Grasshopper Sparrow (Ammodramus savannarum), Marsh Wren (Cistothorus palustris), and Dickcissel (Spiza americana) are good additions to the breeding bird list. Furthermore, Northern Harrier (Circus cyaneus) and Purple Martin (Progne subis) are uncommon species in the area. With sufficient management, it may be possible to entice Purple Martin into establishing a breeding colony at Coffee Creek.
The Marsh Wren is listed as State Endangered. This bird preferentially breeds in cattail or reedy marsh habitat, where it can weave nests hidden and protected among the stems of the cattails. The Dickcissel is a grassland species, which is listed on the National Audubon Society Watch List. The Watch List identifies bird species at conservation risk before they require federal regulation, and therefore, excludes species already federally listed as Threatened or Endangered. With the decline of available prairie habitats throughout the Midwest, many of the grassland species have experienced a decrease in their populations. Other grassland birds found on the site, which are important to note include Savanna Sparrow, Northern Bobwhite,Grasshopper Sparrow and Eastern Meadowlark.
Conservation Considerations
The data from the 2001 and 2000 surveys provides a possible early indication of a decline in the population of two bird species in the Coffee Creek Corridor: Marsh Wren (Cistothorus palustris) and Barn Swallow (Hirundo rustica).
In previous years, several Marsh Wrens, a state listed endangered species, were observed on territory in the vegetation of the pond near station 7. During last year’s count and again this year, no Marsh Wrens were detected. As postulated in last year’s report, either the addition of the large, noisy fountain, the series of artificial waterfalls or the fact that the pond was dredged may be responsible for the absence of Marsh Wren. Marsh Wrens prefer shallow water marshes with tall, dense emergent vegetation. Loud, noisy waterfalls are not a component of a Marsh Wren’s natural habitat.
Again this year, the population of Barn Swallows was very low. In previous years, the swallows had utilized an old, dilapidated barn (near station 8), which was the site of a large nesting colony. However, the barn is no longer standing, having been removed as part of the construction plan, and the swallows most likely had a limited nesting colony size this year.
In addition to species that were encountered during the survey, Appendix 20 lists conservation species with a reasonablechance of using the Preserve during some time of the year.