Monitoring Reports
Section III. Fish Community Survey
Introduction
This report documents fish survey results for Coffee Creek, an indirect tributary to Lake Michigan in northwestern Indiana. The study site is located within the Coffee Creek Watershed Preserve, a 167-acre natural area within Coffee Creek Center. Coffee Creek drains an approximately 16 square mile watershed including agriculture, commercial and r
esidential development, mixed mesic forest and a multitude of wetlands, primarily ground water feed communities in Porter County. The creek flows north to converge with the east branch of the Little Calumet River which ultimately flows into Lake Michigan at Burns Harbor in Portage. Coffee Creek is classified as a spring-fed, coldwater stream with a predominately sand to gravel substrate which offers suitable habitat for migratory salmonids and other lithophilous, non-game species. Significant stream improvements were made in 1999 on the segment of the creek that passes through Coffee Creek Center. However, the upstream, southern reach of Coffee Creek have been ditched in the past. This reach of stream is heavily impacted by bank erosion and channel sedimentation. The yearly surveys of the Coffee Creek fish community document positive or negative impacts on the fish community structure as changes in land use occur in the watershed.
Materials and Methods
The same three 200-foot stream reaches (Figure 1) were sampled each fall (October 10, 1997, November 11 and 12, 1998, October 28, 1999, and October 11, 2000). Reaches 1 and 2 are located in the northern half of the project site, while Reach 3 is located upstream near the confluence of Shooter Ditch and Johnson Ditch with Coffee Creek. Photos of the reaches can be found under separate cover. As in previous years, all three reaches within the study area were sampled twice using a Coffelt Mark 10 backpack electrofishing unit. The unit provides 250 volts and 6-9 amperes of power. Over the four-year period, sampling times varied from 500 to 1437 seconds per reach.
All habitat types within each reach were sampled, and fish were collected, identified to species, measured (in millimeters), and released unharmed at each sample reach. However, up to two vouchers of each unidentified species was preserved in 80% isopropyl alcohol for identification purposes. The percent community composition of each species was calculated for each reach, for each year. Additionally, in 2000, temperature and dissolved oxygen were measured using a YSI model 5500. An Index of Biotic Integrity (IBI) was calculated for comparison among 1997, 1998, 1999 and 2000 studies (Karr, 1981; Simon, 1997; Plafkin et al., 1989).
Index of Biotic Integrity
Biological communities reflect watershed conditions since they are sensitive to changes in a wide array of environmental factors (Karr 1981). Karr (1981) proposed that fish have numerous advantages as indicator organisms for biological monitoring programs. The Index of Biotic Integrity (IBI) was first developed by Karr (1981) and modified by Simon (1997) for evaluating biotic integrity of warm water stream fish communities located in the Northern Indiana Till Plain Ecoregion of Indiana. Karr and Dudley (1981) defined biological integrity as, "the ability of an aquatic ecosystem to support and maintain a balanced, integrated, adaptive community of organisms having a species composition, diversity, and functional organization comparable to the best natural habitats within a region".
Coffee Creek is classified as a cold, headwater stream. Simon's (1997) IBI expectations were developed primarily for warmwater streams. A major difference in fish distribution between coldwater and warmwater streams is readily observable: there are fewer species occurring in coldwater streams (Waters, 2000). According to Simon (1997) all three study reaches of Coffee Creek are characterized as headwater reaches (<20 miles 2 drainage area). Coffee Creek does not necessarily fit the profile of a cold, headwater stream. Darters, creek chub, and green sunfish for example are eurythermic (adapted to broad range in temperature) and are found throughout the study reaches of Coffee Creek. Headwater species, termed stenothermic, are adapted to narrow low temperature ranges but are nonexistent in Coffee Creek. Since the fish community does not strictly adhere to that of a cold, headwater stream and since no index exists to determine biotic integrity in coldwater streams, Simon's (1997) IBI for use in warmwater streams of the Northern Indiana Till Plains of Indiana was used. IBI values for this study may not reflect the actual biotic integrity of the stream due to the reasons mentioned, but does form a base against which future studies can be compared.
The IBI is designed to assess biotic integrity directly through twelve attributes of fish communities in streams. These attributes fall into such categories as species richness and composition, trophic composition, and fish abundance and condition. After data from sampling sites have been collected, values for the twelve metrics are compared with their corresponding expected values (Simon 1997) and a rating of 1, 3, or 5 is assigned to each metric based on whether it deviates strongly from, somewhat from or closely approximates the expected values. The sum of these ratings gives a total IBI score for the site. The best possible IBI score is 60 .
Results and Discussion
The total number of species identified during the 1997 through 2000 sampling included 23 species (19 native to Indiana) representing 7 families. Creek chub ( Semotilus atromaculatus ) and Johnny darter ( Etheostoma nigrum ) have dominated the total number of fish collected at 32% and 26%. Central stoneroller ( Campostoma anomalum ) and white sucker ( Catostomus comersoni ) were also important components of the fish community at 17% and 6% respectively. The minnow family (Cyprinidae) comprised 57% of all fish sampled from 1997-2000 followed by the perch family (Percidae) with 27%. Of the introduced, non-native salmon which migrate from Lake Michigan, rainbow trout (steelhead) adults were the most common, with 23 individuals found over the four-year sampling periods. Of the 1,543 fish collected since 1997, 681 (44%) were tolerant while 132 (9%) were sensitive. Sensitive (intolerant) species are those most susceptible to major types of habitat degradation such as siltation, lowered flow, low dissolved oxygen, and toxic chemicals (Karr et al. 1986). Commonly occurring sensitive species have historically made up 5-10% of the common species sampled in Indiana. No state or federally listed species were sampled from 1997-2000. Appendices 41 through 44 identify the species, number of individuals, and length of individuals found in each reach per year. For a summary of all four years of data, refer to Appendix 45.
Table 3 identifies the trophic guild, tolerance, lithophile, and pioneer status of members of the Coffee Creek fish community. The trophic guild refers to the preferred diet of the species, with generalists preferring wide varieties of animal material, herbivores preferring aquatic vegetation, insectivores preferring insects, omnivores preferring both plant and animal materials, and piscivores preferring fish. Tolerance refers to the ability of species to thrive in degraded environmental conditions. Spawning guilds have been shown to be affected by habitat quality (Balon 1975). Simple lithophils require clean gravel or cobble for success and are most environmentally sensitive (Ohio EPA 1987). Headwater streams generally contain members termed "pioneer species." These species are the first to colonize headwater reaches after desiccation. They predominate in unstable environments and can be indicators of a stressed aquatic system when found in large percentages.
| Common Name | Trophic Guild | Tolerance | Lithophilic | Pioneer |
| Creek chub | generalist | highly tolerant | no | yes |
| Central stoneroller | herbivore | intermediate | no | yes |
| Emerald shiner | insectivore | intermediate | no | no |
| Bluntnose minnow | omnivore | highly tolerant | no | yes |
| Johnny darter | insectivore | intermediate | no | yes |
| Rainbow darter | insectivore | intolerant | yes< | no |
| Blackside darter | insectivore | moderately intolerant- | yes | no |
| Greenside darter | insectivore | moderately intolerant | no | no |
| Northern hog sucker | insectivore | intolerant | yes | no |
| White sucker | omnivore | highly tolerant | yes | no |
| Green sunfish | insectivore | highly tolerant | no | yes |
| Bluegill | insectivore | intermediate | no | no |
| Largemouth bass | piscivore | highly tolerant | no | no |
| Warmouth | invertivore | intermediate | no | no |
| Central mudminnow | omnivore | highly tolerant | no | no |
| Steelhead | insectivore/piscivore | intolerant | yes | no |
| Coho salmon | piscivore | intolerant | yes | no |
| Chinook salmon | piscivore | moderately intolerant | no | no |
| Black bullhead | insectivore | highly tolerant | no | no |
| White crappie | behaviorally plastic | moderate | no | no |
| Brown trout | piscivore | moderately tolerant | no | no |
| Mimic shiner | insectivore | intolerant | no |
no |
Table 3. Trophic guild, tolerance, lithophile, and pioneer status of members of the Coffee Creek fish community. Lithophile refers to a species that prefers rocky stream habitats.
IBI Comparisons
Making among-year IBI comparisons for this particular study is difficult. The time and effort (number of biologists sampling each year) have varied from year to year. With an increased amount of effort, more fish are collected. Additionally, regardless of how much time has been spent sampling, species present in only small numbers may be collected during some sampling efforts but may be missed during others. This probably occurred in the 1998 sampling when one blackside darter and one blacknose dace were documented. Finally, sampling conditions have varied among years. In addition, the 1998 survey likely resulted in lower numbers of collected specimens due to a precipitation event that caused high, turbid flows. Rapidly moving, turbid water can impair a collector's ability to see and capture fish, especially smaller forms like darters and minnows.
In general, the Coffee Creek IBI has been maintained or is slightly improving since 1997 (Table 4). The 2000 IBI estimate classifies Coffee Creek as "Fair". Coffee Creek's IBI suffers due to low percentages of headwater species and lithophilic spawners and high percentages of pioneer individuals. The presence of headwater species indicates permanent habitat with low environmental stress (Simon, 1997). Lithophils require clean gravel or cobble for spawning success and therefore are environmentally sensitive. Pioneer species dominate in unstable conditions impacted by anthropogenic stress and/or temporal desiccation. Although considerable habitat improvements have been made within the Coffee Creek project site, the fish community is still impacted by conditions and practices upstream in the watershed.
| Year | Reach 1 IBI | Reach 2 IBI | Reach 3 IBI | Combined IBI |
| 1997 | 30 | 32 | 34 | 34 |
| 1998 | 34 | 32 | 30 | 40 |
| 1999 | 28 | 34 | 32 | 36 |
| 2000 | 38 | 38 | 40 | 38 |
Table 4. IBI scores by reach and year. Combined IBI is the sum of all three reaches.
Year to Year Comparisons
Figure 14 depicts the percent community composition of dominant and indicator species recorded over the four-year sampling period. Comparing data from year to year is somewhat difficult due to sampling implications already mentioned. Despite the difficulties that exist, there are trends that can be found by looking at percent community composition for each of the four years of sampling (Figure 14).
Figure 14. Relative or percent fish community composition for sampling events in years 1997-2000. Data are shown for the dominant and indicator species.
As shown in Figure 14, highly tolerant species like Creek chub and White sucker are on the decline while species of intermediate tolerance (Johnny darter and Central stoneroller) are increasing components of the fish community. Additionally, the intolerant lithophilic northern hog sucker population is increasing, and the 2000 survey documented young-of-the-year steelhead trout, evidence of successful salmonid spawning in Coffee Creek.
Reach-to-Reach Comparisons
Figures 15 through 18 depict the relative fish community, or percent community composition of dominant species by reach for all four years, 1997-2000.
Figure 15. Relative Fish Community, Percent Community Composition for Dominant Species by Reach for 1997 data.
In 1997, creek chub, a tolerant, pioneer species, dominated the collection at all three stream reaches. Johnny darter, white sucker, and central stoneroller were also important species collected. IBI comparisons between reaches indicated that fish community composition was similar. All received a "Poor" IBI score.
Figure 16. Relative Fish Community, Percent Community Composition for Dominant Species by Reach for 1998 data.
In 1998, white sucker, a tolerant species, dominated the catch at Reaches 1 and 2 while the proportion of creek chub remained relatively stable across reaches. Reach 1 contained no central stoneroller or northern hog sucker in 1998. These species are intermediately tolerant and intolerant (sensitive) respectively. IBI comparisons revealed that a similar trend was occurring from reach to reach. Scores were poor in 1998 and
inhibited by low percentages of headwater species and lithophils individuals and high numbers of tolerant individuals.
Figure 17. Relative Fish Community, Percent Community Composition for Dominant Species by Reach for 1999 data.
In 1999, creek chub dominated the fish collection. However, johnny darter and central stoneroller (both intermediate tolerance) as well as northern hog sucker (sensitive) increased in numbers when compared to the 1997 and 1998 samples. White sucker, a tolerant species declined sharply since 1998. Although some changes occurred in fish community composition, IBI remained "Poor" at all three reaches in 1999. The IBI suffered due to the low percentage of headwater and lithophils individuals and high percentage of pioneer species.
Figure 18. Relative Fish Community, Percent Community Composition for Dominant Species by Reach for 2000 data.
In 2000, Reaches 1 and 2 were similar, but Reach 3 hosted a significantly larger population of the highly tolerant white sucker and a significantly smaller population of the sensitive northern hog sucker (Figure 18). Steelhead juveniles appeared for the first time in Reach 1. Additions of instream habitat may have encouraged successful steelhead spawning in the reach. It is anticipated that future samples in Reaches 1 and 2 will reveal additional steelhead juveniles. Reach 3 supports less than half the numbers of fish supported further downstream. IBI comparisons indicate that fish community structure within all three stream reaches has improved. Reaches 1 and 2 were "Fair-Poor" in 2000, an improvement from that found in 1997-1999. These positive changes in fish community structure reflect the benefits of improved habitat installed in 1999. Although no instream habitat improvements have been installed in Reach 3, the IBI has also improved from "Poor" in 1997-1999 to "Fair" in 2000.