A study of the mussels (Mollusca: Bivalvia: Unionidae) of Symmes Creek and tributaries in Jackson, Gallia and Lawrence Counties, Ohio.

Hoggarth, Michael A. ; Kimberly, David A. ; Van Allen, Benjamin G. 等

ABSTRACT. Freshwater mussels (family Unionidae) are among the most threatened of Ohio's aquatic fauna. Interest in their biogeography has increased as their distribution and abundance has declined. This study was performed to assess the status of the mussels of Symmes Creek and it major tributaries in southern Ohio. Of the 24 species of mussels known to have inhabited this watershed, 16 were found alive in the system in 2004 and 2005 and two others were found as freshly dead shells. These species are thought to represent the extant mussel fauna in the system today. Of the remaining six species collected prior to the current study, three were found alive as single specimens and three were found as very old dead shells and so probably never represented viable populations in the system. During this study, four species were found that had never been reported from Symmes Creek before. These species are Simpsonaias ambigua (Ohio species of special concern), Quadrula pustulosa, Obliquaria reflexa (Ohio threatened species), and Ligumia recta (Ohio threatened species). The Ohio endangered mussel, Villosa lienosa, had been reported from the upper reaches of Symmes Creek previously and was collected alive during the current study, but in much fewer numbers than had previously been reported. The mussel community in the lower mainstem of Symmes Creek has remained healthy while the communities in the headwaters of Symmes Creek and its smaller tributaries have become severely reduced.

OHIO J SCI 107 (4): 57-62, 2007

INTRODUCTION

Watters et al. (in press) have reviewed the status of the mussels of Ohio. Relying on numerous studies of the mussels within specific watersheds by Hoggarth (1986, 1990a, 1990b, 1991, 1992, 1995-1996, 2000), Hoggarth et al. (1995, 2000), and Watters (1988, 1990, 1992, 1998a, 1998b) they concluded that existing mussel community structure within Ohio streams falls into one of three different categories: 1) the mussel community has not been diminished, 2) the mussel community has become greatly reduced from what it was prior to European settlement, or 3) the mussel community had been reduced but has recovered and is approaching similar diversity to pre-European settlement, but with a different suite of species. Watters (1988) concluded that Symmes Creek fell into the first category. He found an abundant fauna both in terms of species richness and number of individuals and concluded that the creek had retained its important ecosystem functions, such as biodiversity.

The intent of the current study was to determine the extent the mussel fauna in this watershed had changed since Watters' (1988) initial study. Prior to Watters' study, five collections had been made in the system (all from Symmes and Buffalo creeks). These studies yielded 12 species of mussels. Watters (1988) collected 20 species from the watershed. Ohio listed species of mussels reported by Watters were Villosa lienosa (lined lampmussel) an Ohio endangered species and Lasmigona compressa (creek heelsplitter) an Ohio species of concern.

MATERIALS AND METHODS

Mussels were collected by hand in the shallow waters of Symmes Creek, Black Fork Symmes Creek, Buffalo Creek, and Long Creek during the summers of 2004 and 2005. The streams were accessed at bridge crossings or adjacent to roads that paralleled the creeks. Particular attention was made to collect from the same reaches as Watters (1988), although additional sites were sampled as well. Generally a reach of at least 200 meters was searched at each site. All living mussels found were taken from the substrate identified to species and returned. Dead shells were retained to voucher the collections. Dead shells were determined to be freshly dead (dead less than one year), weathered dead (dead longer than five years but less than 20 years), or subfossil (dead longer than 20 years). Only living and freshly dead shells were used to determine the presence of an extant population.

RESULTS

The Symmes Creek watershed has been shown to support populations of 24 species of mussels (Table 1). This total includes one Ohio endangered species (V. lienosa), two Ohio threatened species (O. reflexa and L. recta), and two Ohio species of concern (L. compressa and S. ambigua). Prior to this study, 17 species had been found alive in the system, two others were found as freshly dead shells and one additional species was found as a subfossil shell. During the current study 16 living species were found, two additional species were represented by freshly dead shells alone, and one species was represented by weathered shells. Not found during the current study were L. costata (previously found as a single subfossil specimen), Actinonaias ligamentina, Toxolasma parvus, and Villosa iris. The last three species were each previously found as a single living specimen in the system. Discovered for this system for the first time were S. ambigua, Q. pustulosa, O. reflexa and L. recta. Quadrula pustulosa was found alive in sufficient numbers to indicate aviable population in Symmes Creek. Simpsonaias ambigua was found in a limited reach of Symmes Creek mostly under flat boulders where numerous mud puppies (Necturus maculosus) also were found. The fact that so many mud puppies were found in this reach indicates that the potential for a viable population of the salamander mussel also occurs in this creek. Obliquaria reflexa and Ligumia recta were found as single specimens and should not be considered to have viable populations in the creek. These specimens may represent single introductions from fish hosts.

Although it appears that the overall diversity within the system has remained fairly constant over the last 18 years, Black Fork Symmes Creek and the headwaters of Symmes Creek have not retained their mussel faunas. Prior to the current study, Black Fork Symmes Creek supported a community of 13 species of mussels, 12 of which had been found alive. Also, the headwaters of Symmes Creek supported 12 species all of which had been found alive (Table 2). During the current study, only two species were found in Black Fork, only one of which was found alive, and only six species were found in the headwaters of Symmes Creek (Table 3). In addition, Buffalo Creek seems to have lost its entire mussel community, including L. r. luteola, which is among the most tolerant of mussel species, species study documents a severe decline in mussel abundance in the smaller tributaries of Symmes Creek watershed. Black Fork Symmes Creek shows an 85% loss of species and a 98% loss of individuals since 1987 (Tables 2 and 3), and the headwaters of Symmes Creek shows a 50% loss in species and a 72% loss of individuals. Although some different species were found in 1987 and 2004-05 the middle and lower reaches of Symmes Creek showed no loss of species richness and a 50% to 62% increase in numbers of individual mussels found. This apparent loss of species and numbers of individuals is not a result of increased sampling effort as equivalent effort to that done in 1987 was made in Buffalo Creek, Black Fork Symmes Creek, and the headwaters of Symmes Creek during this study.

Within Symmes Creek itself, most species of mussels retained their relative density and distribution (Table 4) while some species either have been in decline or are more abundant and/or more widely distributed in the system. Strophitus undulatus went from a population of 17 specimens distributed over eight sites in 1987 to completely absent during this study. On the other hand, Q. pustulosa went from non-existent in 1987 to a population of 29 specimens (27 at one site) distributed over three sites. Amblema plicata and Tritogonia verrucosa increased their densities and distributions, while V.lienosa became less numerous and had a much smaller distribution than in 1987. Lampsilis r. luteala retained its dominant position in the community but reduced its relative abundance due to increases in other species. Of interest here is the fact that S. undulatus was abundant in the headwaters (which we found to be affected by species lost more than the lower reaches) and Q. pustulosa was found only in the lower reaches of Symmes Creek. Other species with significant changes in distribution were Lasmigona complanata, which went from ten sites to five, and Quadrula quadrula, Leptodea fragilis, and Potamilus alatus, which nearly doubled their distributions. The last two species, and O. reflexa, found in this system for the first time, rely on the freshwater drum (Aplodinotus grunniens) as host for their young and therefore probably indicate an increase in the range of this species in Symmes Creek as well.

DISCUSSION

The mussels of the United States (Neves, 1993) and of Ohio have been in decline for the past several years (Watters et al., in press). In many section of the Midwest, including Ohio, mussel communities have become severely reduced from their historic levels. The upper reaches of Symmes Creek, as well as all of its smaller tributaries, appears to follow this trend. Only the lower mainstem of Symmes Creek has retained its mussel diversity. The reasons for the decline in species abundance and distribution of mussels in the smaller streams in the watersheds is not fully understood at this time, but probably is a result of land-use practices and the subsequent decline in water and habitat quality. Ohio EPA (1999) has demonstrated that water quality (water chemistry) and habitat quality (substrate quality) contribute equally to water resource integrity (essentially a measure of the diversity of the system). Watters (1988) found all these systems (the mainstem and headwaters of Symmes Creek, Black Fork Symmes Creek, and Buffalo Creek) to be healthy and supportive of a diverse mussel community in line with the streams' size. Only the lower mainstem of Symmes Creek has retained its mussel diversity.

Also apparent from our study is the decline within this system of the Ohio endangered mussel, V. lienosa. This headwaters species (Watters, 1992) is restricted to remnants of the old Teays River in southern counties in Ohio. The species is widely distributed in this region, but our study shows how precarious its continued existence can be. This watershed currently does not support sufficient individuals for this species to be considered viable. Watters (1988) suggests that the biggest threat to this species may be impoundment caused by beavers. Although beaver dams were not observed as a threat in the current study, it is possible that all of the dams were gone by the time this study was done and that former impoundment resulted in the loss of the species without subsequent reintroduction. The fact that the loss of headwaters species such as V. lienosa seems to be so widespread would appear to argue for some other reason for decline, and the fact that the de cline affected pool dwelling species such as Utterbackia imbecillis, Pyganodon grandis and Anodontoides ferussacianus equally with riffle and run species (such as V. lienosa) argues for some other explanation as well.

The mainstem of Symmes Creek continues to support a diverse mussel community. Watters (1988) came to this conclusion from collections made in 1987, although he also mentioned that the lower reaches of the creek had more trash in it than any other stream he had ever collected. Trash was not apparent during the current study, but recent flooding had scoured the creek and in some cases changed habitats within its length. These changes have apparently not affected the mussel communities in the lower reaches of this creek, which argues that the mussel community is healthy enough to withstand short-term perturbations. In fact, more individual mussels were collected from the lower reaches of Symmes Creek in 2004 and 2005 than in 1987. These results suggest that the mainsteam of Symmes Creek has remained healthy.

ACKNOWLEDGEMENTS. This study was funded by the Wayne National Forest (FS # 04-PA-11091400-010). We wish to thank Rebecca Ewing, Forest Biologist, for her assistance in the field and her work to secure funding for this project. Other Otterbein students who assisted in the field were Adam Lammers, Mike Frank and Brian Rossiter.

LITERATURE CITED

Hoggarth, M.A. 1986. The freshwater mussels (Unionidae) of the upper St. Joseph River basin within Ohio. Final Report to the Ohio Department of Natural Resources, Division of Wildlife, Columbus, Ohio. 73 pp.

Hoggarth, M.A. 1990a. The Unionidae of the Chagrin River: The remnant of a mollluscan fauna. Ohio Journal of Science, 90 (5): 168-170.

Hoggarth, M.A. 1990b. A Study of the Unionidae of the Olentangy River above Columbus. Final Report to the Ohio Department of Natural Resources, Division of Wildlife, Columbus, Ohio. 27 pp.

Hoggarth, M.A. 1991. A study of the Unionidae of the Little Beaver Creek system. Final Report to the Ohio Department of Natural Resources, Division of Natural Areas and Preserves, Columbus, Ohio. 30 pp.

Hoggarth, M.A. 1992. The Unionidae and Corbiculidae of the Little Miami River system in southcentral Ohio. Walkerana, 6(16):247-293.

Hoggarth, M.A. 1995-1996. The Unionidae (Mollusca:Bivalvia) of the Walhonding River, Coshocton County, Ohio, including the federally endangered catspaw (Epioblasma obliquata obliquata), fanshell (Cyprogenia stegaria), and clubshell (Pleurobema clava) mussels. Walkerana, 8 (20): 149-176.

Hoggarth, M.A. 2000. Studies of the Unionidae (Mollusca:Bivalvia) of the Upper Auglaize River: A search for endangered species. Final Report to the Ohio Department of Natural Resources, Division of Wildlife, Columbus, Ohio. 24 PP.

Hoggarth, M.A., D.L. Rice, and D.M. Lee. 1995. Discovery of the federally endangered freshwater mussel, Epioblamsa obliquata obliquata (Rafinesque 1820) (Unionidae), in Ohio. Ohio Journal of Science, 95(4):298-299.

Hoggarth, M.A., D.L. Rice, and T.L. Groove. 2000. The correlation of musses with fish in the upper Blanchard River in Hardin and Hancock counties, Ohio, with special regard to the rayed bean (Villosa fabalis). In: R.A. Tankersly, D. Warmolts, G.T. Watters, and B. Armitage (editors). Freshwater Mollusk Symposium Proceedings, Part I: Proceedings of the Conservation, Captive Care, and Propagation of Freshwater Mussels Symposium, Columbus, Ohio, March, 1998.

Neves, R.J. 1993.A state-of-the unionid address. Pages 1-10. In: K.S. Cummings, A.C. Buchanan, and L.M. Koch (editors). Conservation and Management of Freshwater Mussels. Proceedings of a UMRCC Symposium, 12-14 October 1992, St. Lewis, Missouri. Upper Mississippi River Conservation Committee, Rock Island, Illinois.

Ohio EPA. 1999. Association Between Nutrients, Habitats, and the Aquatic Bioto in Ohio Rivers and Streams. Ohio EPA Technical Bulletin MAS/1999-1-1.

Watters, G.T. 1988. A survey of the freshwater mussels of the St. Joseph River system, with emphasis on the federally endangered white cat's paw pearly mussel. Final Report to the Indiana Department of Natural Resources, Division of Fish and Wildlife, Indianapolis, Indiana. 127 pp.

Watters, G.T. 1990. 1990 survey of the unionids of the Big Darby Creek system. Final Report to the Nature Conservancy, Columbus, Ohio. 118 pp.

Watters, G.T. 1992. Distribution of the Unionidae in south central Ohio. Malacology Data Net, 3(1-4):56-90.

Watters, G.T. 1998a. Freshwater mussel survey of the Big Darby Creek system in central Ohio. Ohio Biological Survey Notes, 1:19-24.

Watters, G.T. 1998b. Freshwater mussel survey of the Fish Creek system in Ohio and Indiana. Ohio Biological Survey Notes, 1:25-30.

Watters, G.T., M.A. Hoggarth and D.H. Stansbery. In press. Freshwater Mussels of Ohio. The Ohio State University Press.

MICHAEL A. HOGGARTH (1), DAVID A. KIMBERLY (2) and BENJAMIN G. VAN ALLEN (3), Department of Life and Earth Sciences, Otterbein College, Westerville, OH.

(1) Address correspondence to Michael A. Hoggarth, Department of Earth and Life Sciences, Otterbein College, Westerville, OH 43081. Email: mhoggarth@ otterbein.edu.

(2) Current address: David A. Kimberly, Department of Biology, University of Texas at Tyler, Tyler, TX 75701

(3) Current address: Benjamin G. Van Mien, Department of Biology, Virginia Commonwealth University, Richmond, VA 23284

Table 1

Mussels collected from Symmes Creek and tributaries prior to 2004
(Pri) and during this study, 2004 and 2005 (Cur).

 Live Dead Weathered

Species Pri Cur Pri Cur Pri Cur

Utterbackia imbecillis 2 0 0 1 0 2
Pyganodon grandis 124 27 5 5 22 3
Anodontoides ferussacianus 14 1 9 0 6 2
Strophitus undulatus 19 0 10 0 4 0
Lasmigona complanata 49 6 1 2 4 7
Lasmigona costata 0 0 0 0 0 0
Lasmigona compressa (c) 2 0 0 0 2 1
Simpsonaias ambigua (c) 0 1 0 1 0 0
Amblema plicata 58 194 8 3 1 2
Quadrula quadrula 0 6 6 0 1 3
Quadrula pustulosa 0 27 0 0 0 1
Tritogonia verrucosa 30 181 2 6 3 2
Fusconaia flava 24 51 25 6 1 1
Actinonaias ligamentina 1 0 0 0 0 0
Leptodea fragilis 24 40 1 9 1 1
Potamilus alatus 30 37 2 8 1 4
Obliquaria reflexa (b) 0 0 0 1 0 0
Toxolasma parvus 1 0 0 0 0 0
Obovaria subrotunda 0 2 1 0 2 0
Ligumia recta (b) 0 1 0 0 0 0
Villosa iris 1 0 0 0 0 0
Villosa lienosa (a) 43 1 20 0 5 5
Lampsilis r. luteola 268 170 10 4 25 10
Lampsilis cardium 97 110 8 5 4 3
Total number of species 17 16 14 12 16 15
Total number of individuals 787 855 108 51 78 46

 Subfossil Total

Species Pri Cur Pri Cur

Utterbackia imbecillis 0 0 2 3
Pyganodon grandis 0 0 151 35
Anodontoides ferussacianus 0 0 29 3
Strophitus undulatus 0 0 33 0
Lasmigona complanata 0 1 54 16
Lasmigona costata 1 0 1 0
Lasmigona compressa (c) 0 0 4 1
Simpsonaias ambigua (c) 0 0 0 2
Amblema plicata 0 0 67 199
Quadrula quadrula 0 1 7 9
Quadrula pustulosa 0 1 0 29
Tritogonia verrucosa 0 0 35 189
Fusconaia flava 0 0 50 58
Actinonaias ligamentina 0 0 1 0
Leptodea fragilis 0 0 26 50
Potamilus alatus 0 1 33 50
Obliquaria reflexa (b) 0 0 0 1
Toxolasma parvus 0 0 1 0
Obovaria subrotunda 0 0 3 2
Ligumia recta (b) 0 0 0 1
Villosa iris 0 0 1 0
Villosa lienosa (a) 2 0 70 6
Lampsilis r. luteola 0 5 303 189
Lampsilis cardium 0 0 109 118
Total number of species 2 5 20 19
Total number of individuals 3 9 980 961

(a) Ohio Endangered

(b) Ohio Threatened

(c) Ohio Species of Special Concern

live = collected alive

dead = collected as a freshly dead shell (nacre lustrous and
periostracum intact)

weathered = collected as a weathered dead shell (nacre not lustrous
and periostracum intact)

subfossil = collected as a subfossil shell (nacre and periostracum
eroded)

Table 2

Distribution of mussels collected from the Symmes Creek watershed prior
to 2004.

Species 1927-1930 1971

 Symmes Creek Buffalo Creek

 L D W T L D W T

U. imbecillis -- -- -- -- -- -- -- --
P. grandis 0 4 0 4 0 1 0 1
A. ferussacianus 0 1 0 1 0 6 0 6
S. undulatus -- -- -- -- 0 1 0 1
L. complanata 0 0 1 1 -- -- -- --
L. costata -- -- -- -- -- -- -- --
L. compressa -- -- -- -- -- -- -- --
A. plicata 0 5 0 5 -- -- -- --
Q quadrula 0 6 0 6 -- -- -- --
T. verrucosa 0 1 0 1 -- -- -- --
E. flava -- -- -- -- -- -- -- --
A. ligamentina -- -- -- -- -- -- -- --
L. fragilis -- -- -- -- -- -- -- --
P. alatus 0 1 0 1 -- -- -- --
T. parvus -- -- -- -- -- -- -- --
O. subrotunda 0 1 0 1 -- -- -- --
V. iris -- -- -- -- -- -- -- --
V. lienosa -- -- -- -- 0 11 0 11
L. r. luteola 0 6 0 6 0 3 0 3
L. cardium 0 5 0 5 0 1 0 1
Total no. of species 0 9 1 10 0 6 0 6
Total # individuals 0 30 1 31 0 23 0 23

Species 1987 1987-Symmes Creek

 Black Fork headwaters

 L D W T L D W T

U. imbecillis 2 0 0 2 -- -- -- --
P. grandis 60 0 9 69 62 0 10 72
A. ferussacianus 7 1 0 8 5 0 3 8
S. undulatus 10 1 0 11 1 1 0 2
L. complanata 20 1 0 21 20 0 3 23
L. costata -- -- -- -- -- -- -- --
L. compressa 0 0 1 1 1 0 1 2
A. plicata 6 0 0 6 10 0 0 10
Q quadrula -- -- -- -- -- -- -- --
T. verrucosa -- -- -- -- -- -- -- --
E. flava -- -- -- -- 3 1 0 4
A. ligamentina -- -- -- -- -- -- -- --
L. fragilis 18 0 0 18 -- -- -- --
P. alatus 18 0 0 18 1 0 0 1
T. parvus 1 0 0 1 -- -- -- --
O. subrotunda -- -- -- -- -- -- -- --
V. iris -- -- -- -- 1 0 0 1
V. lienosa 14 1 1 16 28 8 6 42
L. r. luteola 36 0 0 36 90 0 4 94
L. cardium 15 0 1 16 34 0 0 34
Total no. of species 12 4 4 13 12 3 6 12
Total # individuals 207 4 12 223 256 10 27 293

Species 1987-Symmes Creek

 middle mouth

 L D W T L D W T

U. imbecillis -- -- -- -- -- -- -- --
P. grandis 2 0 2 4 -- -- -- --
A. ferussacianus -- -- -- -- -- -- -- --
S. undulatus 5 4 3 12 3 0 1 4
L. complanata 7 0 0 7 2 0 0 2
L. costata -- -- -- -- 0 0 1 1
L. compressa -- -- -- -- 1 0 0 1
A. plicata 28 3 1 32 14 0 0 14
Q quadrula -- -- -- -- 0 0 1 1
T. verrucosa 6 0 3 9 24 1 0 25
E. flava 14 23 1 38 6 1 0 7
A. ligamentina 1 0 0 1 -- -- -- --
L. fragilis 4 1 0 5 2 0 1 3
P. alatus 5 0 0 5 6 1 1 8
T. parvus -- -- -- -- -- -- -- --
O. subrotunda 0 0 1 1 0 0 1 1
V. iris -- -- -- -- -- -- -- --
V. lienosa -- -- -- -- -- -- -- --
L. r. luteola 100 1 15 116 40 0 1 41
L. cardium 42 1 3 46 6 1 0 7
Total no. of species 11 6 8 12 10 4 7 13
Total # individuals 214 33 29 276 104 4 7 115

L = collected alive

D = collected as a freshly dead shell

W = collected as a weathered or a subfossil shell

T = total number of mussels collected

Table 3

Distribution of mussels collected from the Symmes Creek watershed in
2004 and 2005.

Species Long Creek Buffalo Creek

 L D W T L D W T

U. imbecillis -- -- -- -- -- -- -- --
P. grandis -- -- -- -- -- -- -- --
A. ferussacianus 0 0 1 1 -- -- -- --
L. complanata 0 0 1 1 -- -- -- --
L. compressa 0 0 1 1 -- -- -- --
S. ambigua -- -- -- -- -- -- -- --
A. plicata -- -- -- -- -- -- -- --
Q. quadrula -- -- -- -- -- -- -- --
Q. pustulosa -- -- -- -- -- -- -- --
T. verrucosa -- -- -- -- -- -- -- --
F. flava -- -- -- -- -- -- -- --
L. fragilis -- -- -- -- -- -- -- --
P. alatus -- -- -- -- -- -- -- --
O. refexa -- -- -- -- -- -- -- --
O. subrotunda -- -- -- -- -- -- -- --
L. recta -- -- -- -- -- -- -- --
V. lienosa -- -- -- -- -- -- -- --
L. r. luteola 0 1 6 7 0 0 3 3
L. cardium -- -- -- -- -- -- -- --
Total no. of species 0 1 4 4 0 0 1 1
Total no. of individuals 0 1 9 10 0 0 3 3

Species Black Fork 2004-Symmes Creek

 headwaters

 L D W T L D W T

U. imbecillis -- -- -- -- 0 1 2 3
P. grandis 2 0 0 2 19 5 3 27
A. ferussacianus -- -- -- -- -- -- -- --
L. complanata 0 2 0 2 3 0 5 8
L. compressa -- -- -- -- -- -- -- --
S. ambigua -- -- -- -- -- -- -- --
A. plicata -- -- -- -- -- -- -- --
Q. quadrula -- -- -- -- -- -- -- --
Q. pustulosa -- -- -- -- -- -- -- --
T. verrucosa -- -- -- -- -- -- -- --
F. flava -- -- -- -- -- -- -- --
L. fragilis -- -- -- -- -- -- -- --
P. alatus -- -- -- -- -- -- -- --
O. refexa -- -- -- -- -- -- -- --
O. subrotunda -- -- -- -- -- -- -- --
L. recta -- -- -- -- -- -- -- --
V. lienosa -- -- -- -- 1 0 5 6
L. r. luteola -- -- -- -- 30 1 4 35
L. cardium -- -- -- -- 1 1 2 4
Total no. of species 1 1 0 2 5 4 6 6
Total no. of individuals 2 2 0 4 54 8 21 83

Species 2004-Symmes Creek

 middle mouth

 L D W T L D W T

U. imbecillis -- -- -- -- -- -- -- --
P. grandis 6 0 0 6 -- -- -- --
A. ferussacianus 1 0 0 1 -- -- -- --
L. complanata 2 0 2 4 1 0 0 1
L. compressa -- -- -- -- -- -- -- --
S. ambigua 1 1 0 2 -- -- -- --
A. plicata 182 2 1 185 12 1 1 14
Q. quadrula 0 0 2 2 6 0 1 7
Q. pustulosa 0 0 1 1 27 0 1 28
T. verrucosa 35 4 0 39 146 2 2 150
F. flava 41 3 1 45 10 3 0 13
L. fragilis 29 4 0 33 11 5 1 17
P. alatus 29 6 2 37 8 2 3 13
O. refexa -- -- -- -- 0 1 0 1
O. subrotunda 1 0 0 1 1 0 0 1
L. recta -- -- -- -- 1 0 0 1
V. lienosa -- -- -- -- -- -- -- --
L. r. luteola 103 0 1 104 37 2 1 40
L. cardium 94 1 1 96 15 3 0 18
Total no. of species 12 7 8 12 12 8 7 13
Total no. of individuals 524 21 11 556 275 19 10 304

L = collected alive

D = collected as a freshly dead shell

W = collected as a weathered or a subfossil shell

T = total number of mussels collected

Table 4

Mussels collected in 1987 and 2004-05 from Symmes Creek.

Species 1987 # 1987% 1987 D 2004/5 #

U. imbecillis 0 0.0 0 3
P. grandis 37 5.7 8 34
A. ferussacianus 8 1.2 3 1
S. undulatus 17 2.6 8 0
L. complanata 33 5.1 10 13
L. costata 1 0.2 1 0
L. compressa 3 0.5 3 0
S. ambigua 0 0.0 0 2
A. plicata 56 8.6 7 199
Q. quadrula 1 0.2 1 9
Q. pustulosa 0 0.0 0 29
T. verrucosa 34 5.2 6 189
F. flava 49 7.5 11 58
A. ligamentina 1 0.2 1 0
L. fragilis 8 1.2 6 50
P. alatus 14 2.1 7 50
O. reflexa 0 0.0 0 1
O. subrotunda 2 0.3 2 2
L. recta 0 0.0 0 1
V. iris 1 0.2 1 0
V. lienosa 42 6.4 7 6
L. r. luteola 251 38.5 19 178
L. cardium 94 14.4 17 128
Total number of individuals 652 953
Total number of species 18 18

Species 2004/5 % 2004/5 D

U. imbecillis 0.3 3
P. grandis 3.6 8
A. ferussacianus 0.1 1
S. undulatus 0.0 0
L. complanata 1.4 5
L. costata 0.0 0
L. compressa 0.0 0
S. ambigua 0.2 2
A. plicata 20.9 11
Q. quadrula 0.9 6
Q. pustulosa 3.0 3
T. verrucosa 19.8 9
F. flava 6.1 13
A. ligamentina 0.0 0
L. fragilis 5.2 10
P. alatus 5.2 14
O. reflexa 0.1 1
O. subrotunda 0.2 2
L. recta 0.1 1
V. iris 0.0 0
V. lienosa 0.6 3
L. r. luteola 18.7 22
L. cardium 13.4 18
Total number of individuals
Total number of species

D = distribution: the number of sites where the species was collected.