ML19210B856
| ML19210B856 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 01/24/1970 |
| From: | Wurtz C LA SALLE COLLEGE, PHILADELPHIA, PA |
| To: | |
| Shared Package | |
| ML19210B855 | List: |
| References | |
| NUDOCS 7911120553 | |
| Download: ML19210B856 (18) | |
Text
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A BIOLOGICAL SURVEY OF THE SUSQUEHANNA RIVER IN ThE VICINITY OF YORK HAVEN, PA.
1967 PROGRESS REPORT prepared for PENNSYLVANIA POWER & LIGHT COMPANY and METROPOLITAN EDISON COMPANY by
' Charles B. Vurtz Cca uiting :. c!cgis:
La Salle College.
Philadelphia, Pr..
o submitted 9 August 1968 0
con 006 su o *
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- Bnv Y a m e M e Mul XlAL 74//120 63
4 CONCLUSIONS
- 1. A biological survey based on macroinvertebrate organisms (bottom organisms) produced 149 species and demonstrated that the Susquehanna River in the vicinity of York Haven was biologically normal from above Threemile Island to Haldeman Riffle.
- 2. There are strong ecological differences between the river above the York Haven Dam and the river below the dam.
- 3. The biological structure of the river, as measured by a coefficient of variation, reflects a stable community structure in equilib-ium with the environment.
- 4. T'ie biological materials show a high degree of variance as a product of high species diversity due to ecc!cgical ditterences.
- 5. One station (Station 5) was found to be aberrant due to high variation in ficw char,acteristics. This station will be deleted from subsequent surveys.
- 6. One station (Station 8) was found to have water temperatures elevated above normal ambient temperatures, but the increased temperature had not appreciably altered the resident fauna at the station.
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A BIOLOGICAL SURVEY OF THE SUSQUEHANNA RIVER IN THE VICINITY OF YORK HAVEN, PA.
INTRODUCTION This survey was undertaken in'the interests of the Pennsylvania Power and Light Company and the Metropolitan Edison Company. The two companies jointly sponsored the work, which included a study of the Susquehanna River in a stretch extending from above Threemile l_sland dcunstream to Haldeman Riffle.
The Survey consisted of a study of the macroinvertebrate fauna (bo. tom organisms) at each of n'ne stations. Field work was begur. August 7, 1967, and contir.ued through August 18, 1967 The field work was pe, formed by Drs. Charles S. Vurtz and John S. Penny.
Mr. Lynn Ratzell of the Pennsylvania Power and Light Company ' accompanied the consultants during the field work.
Water quality characteristics were measured by laboratory personnel of the Pennsylvania Power and Light Company.
STATIONS Nine stations (sampling sites) were collected. The location of each station is indicated on Figure 1, a map of the general area
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o of investigation. The list of stations with pertinent comments follows.
Station 1.
This station was in the riffle area above Threemile Island and between the head of Fall Island and the eastern shore. Along the eastern shore the substrate was anaerobic at depths of two or more. feet as indicated by the production of hydrogen sulfide.
Station 2.
This stacion was between the northern tips of Threemile.sland and Shelley Island.
..vt off Shelley Island a sandy bottem was found to depths of five feet.
Fragments of large uni..nid clam shells were found f.e.e, but no living specimens were taken at any station dur.ng the survey.
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S ic i s on 3 Tle s s s la t i on aniciidsd '0.6"....~. the ;Oeth0Tr. KIP' of Shelley Island and the western sher of Threemile Island at the " Ball Lai" summer cottage. Depths reached ten feet at this s ta t ion...inaerobic bottom conditions occurred in depths as shallow as two feet.
Station 4.
This station extended from the southern tip of Shelley Island to the southern tip of the next Island west of Shelley Island. The station had depths to nine feet, and was characterized by extensive aquatic plant growth. One plant, a species of 7cIlisneria, is reputed to have been introduced by the State as a duck food. This plant occurs as a nuisance growth.
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Station 5 This station was located across the channel from the southern tip of Threemile Island below the York Haven Dam. The staticn was aberrant in its physical characteristics because of widely fluctuating water levels. This station will be deleted from further studies.
Station 6.
This station was located along the western shore of the river above the mouth of the Conewago Creek.
Depths did not exceed one and one-half feet at the time of collecting. Near the shore the river had a mud substrate, while of# shore an extensive. growth of Polygonum was present.
Stat on 7 This station was located between the northern
' Eiiiot) islana ano the eas terri niiore.
Deptiin tip oi-raldeman
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reached & bout five feet.
Station 8.
This station was located along the western shore abou. one mile below the discharge canal of the Brunner Island Plant. Depths did not exceed two feet and heavy silt deposits covered the substrate material.
- Station 9 This station was located at the right edge of Haldeman Riffle and included a shoaling mud flat below the riffle.
This mud flat supported an extensive growth of emergent aquatic plants.
Depths did not exceed one and one-half feet.
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WATER QUALITY On August 18, 1967, one set of water samples was taken for
. water quality analyses by the laboratory personnel of the Pennsylvania Power and Light Company. No sample was collected at Station 5 because this station was inaccessible on the day of collection.
The analytical work was performed September 15, 1967, after nearly one month of storage. Since some water quality charac-teristics are unstable it would appear inappropriate to include recorded measurements for these here. Thus results of.the hydrogen ion concentration and free carbon dioxide tests are not included here. Phenolphthalein alkalinity (as CACO 1 was 3
repcrted 'dr Stations 6, 8, and 9 The reported values were We assume this 10.0, 2.0, and 5.5 parts per million respectively.
analysis was not performed on the other samples since the submitted data sheet presents a dash (-) in the results column under the other stations. The presence of phenolphthalein alkalinity implies the presence of free hydroxids. This appears unlikely in stored samples and this occurrence must be considered anomalous.
Results of the analytical tests are presented in Table I with results expressed as parts per million.
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Table 1 Water Quality Characteristics Station Methyl Orange Total Chlorides Suspended Alkalinity Hardness (as Nacl)
Matter (as CACO )
(as CACO )
3 3
1.
34.0 105.0 15.0 12.5 2.
31.0 132.5 14.0 15.5 3
31.5 119.0 14.0 8.4 4.
28.0 78.5 9.5 4.4 6.
60.0 93.0 14.0 23 7 7.
32.0 110.0 14.5 17.5 8.
65.5 96.5 13 5 16.5 9
69.5 104.5 i5.5 22.8 The samples contributing the data to Table.I represent single grab su oles and would, therefore, be expected to reflect broad variatior. Nevertheless, the icfluence of Conewago Creek water along the western shore can be identified at Stations 6, 8, and 9 Station 7, as expected, appears to be in the flow of above-dam waters and has the characteristics of those waters. This condition would probably be' disrupted under conditions of continuous low flow when virtually all above-dam water is discharged through the hydro plant at York Haven.
Station 4 flow represents water passing down the west side of Shelley Island. The quality differences probably refle'ct the influence of an influx of water from sources other than the main stem of the river.
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The water quality was not influenced by the anaerobic bottom conditions observed at Stations 1 and 3 This anaeroblasts Is. Interpreted as a product of cumulative organic debris associated with low velocities.
Water quality characteristics. measured in the field included dissolved oxygen concentrations and temperature. These character-Istics were measured August 18, 1967, coincident with the collecting of the water samples. Table 2 presents these data.
Table 2 Dissolved Oxygen and Tecnperature Station Time Depth Dissolved Oxygen (ppm) Temperature (*i-)
1.
142G Sus i.w 5.0 00.0
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1400 Surface 10.0 80.6 5'
10.0 80.6 3
1345 surface 9.0 80.6 5'
9.0 78.8 8'
9.0 78.8 4.
1300 surface 8.0 78.8 5'
7.5 77.0 9'
7.5 77 0 6.
1100 1.5' 9.75 78.8 7
1035 surface 7.5 78.8 3.5' 75 78.8 8.
0940 surface 7.0 98.6 2'
7.0 98.6 9
0835 1.5' 6.0 86.0 6
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Biological collections were made at Station 8 on August 16th.
On that date the right shoreline water temperature ranged from 96.0 F to 100.0 F at 1:30 PM.
Offshore, at the head of the Island, the water temperature was 90.0 F at 9: 15 AM.
Although these elevated temperatures were found at Station 8 all tempera-tures and dissolved cxygen concentrations at all stations were apparently within biologically acceptable ranges for the r.esident macroini-rtebrate organisms.
The Pennsylvania Power and Light Ccmpany provided river flow data for the period preceding and including the field work. ' River flow diminished almost continuously cucing the survey; discharge lowering from approximately 35,000 cfs on August 7 to approximately 5,900 cfs on August 18.
(A slight, trsnsient, rise occurred August 10.) The peak flow immediately preceding the beginning of the surve) was approximately 37,000 cfs on August 6.
Average discharge during the 12 days of the survey period was approximately 19,590 cfs.
During the 12 days preceding the survey, average discharge was approximately 19,900 cfs.
In the 12 days preceding the survey river elevation ranged from 252.18 to 254.88 feet: a range of 2.70 feet. During the 12 days of the survey period river elevations ranged from 251.61 to 254,77 feet: a range of 3.16 feet..
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River flow data indicate that the physical characteristics of the river, with the exception of Station 5, were not extreme enough to influence the resident fauna of macroinvertebrate organisms.
Station 5 was physically limiting for bottom organisms because of fluctuating water levels. At times of low flow, when no water spills ever the York Haven Dam, Station 5 would have essentially intermittent flow. Any flow that did occur would consist only of the discharge from Conewago Creek
- and seepage Icsses from the impoundment.
- This would be the small Conewago Creek draining into the eastern side of the river above the community of Falmouth, it is not to be confused with the larger Conewago Creek draining into the western side of the river at York Haven.
BIOLOGICALCOLLECTI0td A total of 149 species of macroinvertebrate organisms was collected during the survey. These are listed in Appendix A, which also shcws the distribution of the species by station. '
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The collections are summarized in Table 3 Both the number of species at each station as well as the percentage of the total number (149 species) is presented.
e Table 3 Macroinvertebrate Collections Station Non-insect Species Insect Species Total Species Number Percent Number Percent Number Percent 1.
20 13 23 15 43 29 2.
18 12 28 19 46 31 3
19 13 16 11 35 23 4.
20 13 28 19 48 32 5
4 3
19 13 23 15 6.
12 8
44 30 56 38 7
13 9
32 21 45 30 8.
7 5
32 21 39 26 13 9
57 38 70 47 The macroinvertebrate fauna as pre.sented in Table 3 is split into two facets: non-insects and insects. The non-insect complex o
(Species 1-41 in Appendix A) represent those organisms continuously in the environment and subject to all the environmental present Influences of that habitat. The Insects, in general, have adult At such times, stages that are independent of the aquatic habitat.
of course, they are not subjected to the environmental influences of the river itself. This fundamental difference between the two groups justifies consideration of them as two components of the macroinvertebrate fauna.
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In all biological communities the organis'ms that contribute to species diversity are present in a gradient ranging from most abundant to extremely rare. This ecological concept can be measured by the number of individuals of a species present within a given area, or, as is done here, by the frequency of occurrence of the species among the several stations ef a survey.
Nine dominant species (6% of the total) are recognized here. Table 4 lists these dominant forms.
Table 4 Dominant Species Present at ill nine stations.
- 1. Sr.:1!, Pa;*~ accenantwopha
- 2. Midge larva, Polypeditwn-sLLinoense Present at eight stations:
- 3. Yorm, Lir:nodriIua cf. hoffmeisteri
- 4. Limpet (Snail), Ferrissia tarda
- 5. Water strider, resovetic muIsents
- 6. Caddisfly nymph, Eydropsyche sp. I Present at sEven stations:
- 7. F1atworm, Dugesia tigrina
- 8. Bryozoan, PlumateLZc repens
- 9. HIdge 1arva, Tanytarsus e=ip a Within the stretch of the river studied.the nine' dominant species represent the most characteristic faunal element. Table 5 presehts the frequency of dominant species at each station. -
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Table 5 Dis :ribution of Dominant Species Station 1
2 3
4 5
6 7
8 9
Number of Do.,inant Species 9
9 6
7 5
9 9
8 9
Those stations contr.ining less than 25% of the total species collected (Stations ; and 5) also have the fewest number of species from the dominant group in their community structure.
Station 5 included only 15% of the total fauna and is so aberrant (for reasons stated earlier) that it will be dropped from furore surveys.
In a. letter dated August 23, 1967, it was propo,ed to relocate Station 5.
However, the analyses of the data from the 1967 survey show that there is no need to continue sampling in this area.
Of the 149 species col,lected 56 (38%) occurred as unique
- species, i.e., occurred at only one of the nine stations. This
' falls within the range of normal biological structure relative to species diversity.
Figure 2 presents the number of species taken at each station as a percentage of the total number collected. The mean percentage value is represented by a horizontal line.
Figure 3 is an ogive and shows the accumulation of additional species with each succeeding station. Although the curves imply a
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linear sequence in the stations, this is not,-in fact, the case.
Stations 3 and 4 are essentially paired stations and are geogra-phically parallel for all practical purposes.
STATISTICAL ANALYSES Comprehensive qualitative biological collections, such as is represented by the collections made during this survey. are readily amanable s quantitative techniques. The statistics derived here are descriptive statistics that provide comparative figures for future surveys.
Such statistics also invite comparisoa with comparable surveys from other locations.
ine basic statistics aevelopea incluce tne mean (E),
2 standard cavlation (s=/Ed2/n-1), variar.ce (s ), and the coefficient of variation (V=100s/i). The first two are common statistics.
Variance, widely used in ecology, increases with increasing diversity in the number of species present among the stations of a survey area. The coefficient of variati.on is a measure of variation about the mean. With increasing biological stability the value of V lowers. Values of less than about 20% to 25% represent long-term biological equilibrium, i.e.,
the resident population has come into equilibrium with the environmental influences. ~1570 079
Table 6 summarizes the descriptive statistics derived for various aspects of the data.
Table 6 Descriptive Statistics 2
x s
s y
Total species at all stations 45 13.13 172.50 29.2%
Total species excluding aberrant Station 5 48 10.93 119.43 22.8%
Non-insects at all stations 14 5.79 33 50 41.4%
. Non-insects excluding aberrant Station 5 15 4.72 22.29 31.5%
Insects at all stations
'31 12.73 162.25 41.1%
insects excluding aberrant Station 5 33 12.75 162.57 38.6%
When the aberrant Station 5 is de12ted f rcm the data the total species n::ber reflect biological stability in the stretch of the river stuuled.
There is a high degree-of variance in the collections. This is a reflection of high species diversity among a series of stations that vary ecologically because of physical differences. Obviously, the variance is chiefly associated with the insects. The ecological differences leading to this diversity include variation in substrate material, flow velocity, depth, etc.
When the stations are divided into an above-dam grcup (Stations 1-4) and a below-dam group (Stations 6-9) the descriptive statistics.
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'A reflect greater stability within each group. Table 7 presents these statistics.
Table 7 Descriptive Statistics Relative to York Haven Dam 2
I s
s y
Total species above the dam 43 5.71 32.66 13.3%
Total species below the dam 56 14.21 202.00 25.4%
Hon-insects above the dam 19 1.00 1.00 0.05%
Non-Insects below the dam 11 2.88 8.33 26.2%
insects above the dam 24 5.68 32.33 23.7%
Insects below the dam 41 11.80 139.33 28.8%
Fron the data in Table 7 it is apparent that ecological cannernns cerrar oe.cween tiie auuve-Ue... and valuw Jam =iatici...
The above-dam stations tend to resemble each other ecologically and biological equilibrium is clear-cut. The stations below the dam differ from each other ecologically and this is reflected in
.the high variance. At the same time, this part of the river can be considered in biological equilibrium w.ith the environmental influences.
The. coefficient of variation of 0.05% for non-insects above the dam is the lowest value for this statistic ever found by the consultant. This is an uncommon degree of stability..lb,O Coi
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Dayhaw's chi-square test *for comparing two sets of chserved 2
data was applied to the data. No significant difference (x =2.26) was found when the total number of species from above the damowas compared with the total number from below the dam (excluding Station 5). The same conditions prevailed in a siniilar comparison of the non-insect component (x =1.55) and the insect component (x =3.45).
However, when the same test was applied to non-insects versus insects for all stations, exclusive of Station 5, a highly significant difference (p=<.01) was found with a chi-square value of 24.56. This significantly different value reflects the ecological dif ferer.ces between above-dam and bele.a-dam stations.
In a 1967 four-station survey of the Susquehanna River at Sunbury nu significant differences were found between non-insects and insec:s. The stations at the Sunbury location were more closely comparable to the a,,bove-dam stations at York Haven than to the below-dam stations. At the Sunbury location 83 species were taken in June while 66 species were taken in September, which was a period of very high water. At Stations 1 through 4 of the York Haven survey 95 species were collected. This larger number of species reflects increased river size and diversity of habitat 2
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Stations 6 through 9 of the York Haven survey produced 111 species, reflecting further Increases in habitat diversity; particularly at Station 9, which supported 18 uniqua species.
A coefficient of correlation
- of 0.542 was found between non-insects and insects for all stations exclusive of Station 5
" Figure 4 presents a scatter diagram of these data as well as the line of least squares, for which Y=21.74+(-0.200)X.
The two components of the macroinvertebrate fauna reflect, at best, but moderate correlation and tend to be independent of each other.
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9 APPENDIX A a
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4 a
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APPENDIX A MACR 0 INVERTEBRATE SPECIES Stations 1 2 3 4 5 6 7 8 9 FLATVORMS
- 1. Dugesia tigrina x x x x x x x
- 2. cf. Curtisia foremani x
x
- 3. Prostcma rubrum x
WORMS
- 4. Limnoddlus cf. hoffmeisteri x x x x x x x x 5 Tubife::
x
- 6. Braitchiura scuerbyi x x x
- 7. Lumbriculidae g. sp. 1 x x x
- 8. Lumbriculidae g. sp. 2 x
- 9. Megascolecidae g. sp. I x
- 10. Mega:colecidae g. sp. 2 x
- 11. Oli, chaeta f. g. sp. 1
.x 3
IFECHES ii. Eukbdalk u.v;..L.d..
~.
r.
v
- 13. Placebdella rugosa x
x x x
- 14. Placoldella mon:ifera x
- 15. Erpobdsila punc:ata x x x
- 16. Hirudinea f. g. sp. I x
o BRYOZOANS
- 17. Fredericeila suitana x
- 18. Plumatella recens x x x x x x x
- 19. Paludicella a'rticulata x
x 20.'Urnatella gracilis x
x x
- 21. Lophcyodella carteri x
CLAMS
- 22. Sphaerium sp. 1 x x
- 23. Pisidium sp. 1 x x x x SNAILS
- 24. Campelcma integr'.ct x x
- 25. Amnicola limosa x x x x x
x
- 26. Amnicola sp. 1 x
x
- 27. Valua:a tricarinata x
.{-
- /
APPENDIX A MACR 0 INVERTEBRATE SPECIES Stations 1 2 3 4 5 6 7 8 9 FLATVORMS
- 1. Dugesia tigrina x x x x x x x
- 2. cf. Curtisia foremani x
x
- 3. Proscor a rubrum x
WORMS
- 4. Limnodritus cf. hoffbeisteri x x x x x x x x
- 5. Tubife x
- 6. Branch +.wa soverbyi x x x
- 7. Lumbriculidae 9. sp. 1 x x x
- 8. Lumbri ulidae g. sp. 2 x
- 9. Megastolecidae 9. sp. I x
- 10. Megascolecidae g. sp. 2 x
- 11. Oligochaeta f. g. sp. I x
IFFCHES
~
- 12. Estubda;la n.9' M 'de -
r.
r.
- 13. Plce:biella rugosa x
x x x
- 14. Placo',deLIa contifera x
- 15. ErpoMella punc:ata x-x x
- 16. Hirud'.nea f. g. sp. 1 x
BRYOZOANS
~
- 17. Fredericella sultana x
- 18. Plumatella recens x x x x x x x
- 19. Paludicella ai'ticulata x
x
- 20. Urnatella grac'Lis x
x x
- 21. Lophopodalla carteri x
CLAMS
- 22. Sphaerium sp. I x x
- 23. Pisidium sp. I x x x x SNAILS
- 24. Campel :n int.:grum x x
- 15. k:niccia limosa x x x x x
x
- 26. Amnicola sp. I x
x
- 27. Valuata tricarinata x
-l-d yg 1550 091 D*o o
b..Niido a
~
~
Stations 1 2 3 4 5 6 7 8 9 SNAILS, cent'd.
- 28. Gonicbasis virginica x x x x
- 29. !!itocris carinatus x x x
x x x x x x x x x
- 30. Physa heterostropha
- 31. Ferrissia tarda x x x x x x x x x
x x
- 32. HeLiscma anceps x x
- 33. Helisoma tricoivis
- 34. Gy m ius sp. 1 x
x x x
- 35. Gyrautus sp. 2 x.
x x x x
x x
- 36. L2::naia h:ctiZus CRAYFISH x
x x
- 37. Orconcoces sp. 1 S0WBUG x
- 38. Aselius cor:mmia SCUDS
- 39. Hy.:lella azteca x
x x
x x x
x
- 40. Gar:rarus facciatus
- 41. Crargonya gracilia x x x
HAYFLtES x
- 42. He :cgenia sp. I
- 43. 5tenonema sp. 1 x x x x
- 44. Stenonema sp. 2 x x x
x x
x x x
- 45. Scencnema sp. 3 x
x
- 46. Stenonema sp. 4 k
x
- 47. Stencnema sp. 5 x
- 48. Stencnema sp. 6
- 49. Isonychia sp. 1 x
- 50. Tricorsthedes sp. 1 x
x x
51..Tricorsthodes sp. 2 x
x
- 52. Tricorsthodes sp. 3 x
- 53. Tricorsthedes sp. 4 x
- 54. Tricorithodes sp. 5
~
x
- 55. Tricorschedes sp. 6
- 56. Leptohyphes sp. 1 x
x x
- 57. Caenis sp. 1 x
- 58. caenis sp. 2 x
x
- 59. Cacnis sp. 3 x
x
- 60. Caenis sp. 4 x
- 61. Caenis sp. 5 x
- 62. Pseudocicecn sp. 1
- 63. Baecinae g. sp. I x
x x x x
Stations.
1 2 3 4 5 6 7 8 9 MAYFLIES, cont'd.
- 64. Baetinae g sp. 2 x
x
- 65. Baetinae g. sp. 3 x
- 66. Baetinae g. sp. 4 x x x
- 67. Baecinae 9. sp. 5 x
DRAGOllFLIES
- 68. Macro:nia sp. 1 x
- 69. NeurocorduLia sp. 1 x
DAMSELFLIES
- 70. Argia sp. 1 x
x x
- 71. EnaIZag a sp. I x
- 72. Enalap a sp. 2 x.
x
- 73. Enallag a sp. 3 x
x
- 74. Enatlap.= sp. 4 x
- 75. ef. Te!caIIar a sp. I x
- 76. Ischnura sp. 1 x
x x x x
- 77. Ischnura sp. 2 x
x x x x a
x x
- 75. Io&c :. }
'79. Ischn wa sp. 4 x
x x x
- 80. Ischraea sp.5 x
x
- x. x x
- 81. East 6.~~na sp. 1 x x x
x x x VATER STRIDERS AND WATER BUGS 8'. Gerris sp. 1 x
x x x x
- 83. Metrobates sp. I x
x
- 84. Rhew.atabates sp.1 x
.x x
x
- 85. Trepobates sp. 1 x
x x x
- 86. Trepoba es sp. 2 x
x x x x x
- 87. Trepobates sp. 3 x
- 88. Mesovelia muisanti x x x x x x x x
- 89. Selcstor.a sp. I x
x
- 90. Microvelia sp. I
'x x
- 91. Corixinae g. sp.1 CADDISFLIES
- 92. Hydropsyche sp. 1 x x x x x x x x
- 93. Triaenodes sp. I 2.
x x x x
- 94. Oecetis sp. 1 x x
- 95. Cecatis sp.2 x
- 96. Athrigsodes sp. 1 x
x
- 97. Rhyacophila sp. 1 x
- 98. Neureclipsis sp. 1 x
r, - 7
.ggg.
Jc-a>J u
J em P]Dh3'Th g
D oJuuS..kini:
o o Ju 2
Stations 1 2 3 4 5 6 7 8 9 MIDGE LARVAE, cont'd.
130. Cricotcpus fuga:
x 131. Cricotopus slossonae x-x 132. Cricotcpus sp. I x x x x x x
133. Orthociadius dorecas x
134. Orthocladius carlatus x
x x
135. 2"e.alassc=gia obscurus x
x' 136. Tanytarsus e=igua x x x x x x x 137. Tanytarsus flavipes x x 138. Tanytarsus sp. I x
x 139. Polypedilun illinoense x x x x x x x x x 140. Stictcchironceas sp. I x
141. Chironomus jucundus x
142. Chironc~:us ricarius x
x' x x x l43. Chironc=as ab'rtiva o
x 144. Chironc=.ts nais x
145. Chironc=as nr. fulvus x x x x
146. Chiron;=as sp. 1 x x x x 147. Glyptatendiges dreisbachi x
x x
x 148. Glucutendices colutc=as x
x x x 149.Gliptetendiges'senitis x x x x 8888888 e
e
.y.
j
e
- Stations 1
2 3 4 5 6 7 8 9 HOTHS
- 99. Percpoync sp. I x
x 100. Parcrgyractis sp. 1 x
LARVAL BEETLES 101'. Berosus sp.1 x
x x
102. Elmidae g. sp. I x
x x
103. Elmidae g. sp. 2 x
x x
104. Elmidae g. sp. 3 x
105. Elmidae 9. sp. 4 x
x 106. Elmidae g. sp. 5 107. Eubrianca sp. 1 x
x ADULT BEETLES 108. Berosinae g. sp. 1 x
x 109. Egdrochus sp. I x
x x x x x 110. E opi.:ternus sp. I x
111. Lacco~ hilus sp. 1 x
112. Peltodytes sp. 1 x
113. Stens?.wis 'sp. 1 x
x x
x 114. Stene M s sp. 2 5
x x y
115. Scenc7. mis sp. 3 x
116. Stencimis sp. 4 x
4 I '#. h ?".4'M4 [llT$3 30.
3 118. Stenelmis sp. 6 r.
119.. Doncc'.c sp. I x
BLACKFLY 120. SimuZi:ca sp.1 x
x x x x x
DANCEFLY 121. Empididae g. sp. 1 x x
.x x
x HORSEFLY 122. Chrysops sp. 1 x
/
MIDGE LARVAE 123. Tanypus melancys grp.
u n x
x 124. Tcnypus monitis grp.
x x x
.x x
125. Tanypus carnec 126. Procladius caliciformis x
x x x x x 127. Procicdius rip rius 128. Clinotanovus ::t,racius
.x 129..?sectrockiius nigrus x x x x
~
-iv-
]"20 095 D**D T' }km
- 1. g oc o
A BIOIOGICAL SURVEr OF TIE SUSQUEHANNA RIVER IN THE 7ICINITY OF YOPZ HAVEN, PA.
1968 PROGRESS REPORT prepared for PENNSYL7ANIA PCWER & LIGHT CCMPANY ara METRCPOLITAN EDISCN COMPANY by Charles B. Wurtz Consulting Biologist La Salle College Philadelphia, Pa.
submitted 24 January 1970 F ^ G,
[J1 F; U J/v s
e
CONCitJSIONS 1.
The York Haven area of the Susquehanna River produced 119 species of macroirrrertebrate species (botten organisms) in 1968. The co= parable 1967 surrey produced 11+5 species.
2.
Differences in biological structure between 1967 and 1968 are presented, and these generally indicate, statistically significant differences between the two years.
3 In 1968 the river appeared biologically depressed over 1967, and this was chiefly associated with a reduction in the insect fauna.
h.
One cause for the obserted changen would be the con-tirmous low flow to the river for an extended period of time during 1968.
5 There are strong indications that the river suffered frge the introduction of a toxicant during the su=mer of 1968.
6.
The area of biologicel depression extended from Station 2 through Station 8.
Station 9. the west end of Haldeman Riffle, did not appear strongly affected.
e 7
r, ^ ~I l
,nJ U-J
A BI0IfGICAL SURVET OF THE SUSQUEHANIA RIVER IN THE VICINITY OF YOPZ HAVEN, PA.
INTRODUCTION This surrey was the second biological surtey undertaken in the interest of the Pennsylvania Power & Light Company and the Metropolitan Edison Company. The surrey represents a study of the macroi:rtertebrate fauna (bottom organisms) at each of a series of eight stations. Field work extended from August 12 through August 20, 1968.
STATICIS Eight stations (sa=pling sites) were collected. The locatien of each station was irdicated on Figure 1 of the first progress report submitted August 9,1968. The statiens studied are listed below.
Station 1.
This station was in the riffle area above Three Mile Island and between the head of Fall Island and the eastern shore. Along the eastern shore the substrate contained anaerobic pockets.
Station 2.
This station was between the northern tips of Three Mile Island and Shelley Island.
Foq n^
.3,J Uiu
Station 3 This station extended from the southern tip of Shelley Island to the western shore of Three Mile Island at the
" Bali Lai" su=mer cottage.
Station 4.
This station extended from the southern tip of Shelley Island to the southern tip of the next island west of Shelley Island.
Station 5 This station, included in the first survey, has been deleted from the program. However, the original station numbers are retained to facilitate comparisons between the reports to date.
Station 6.
This station was located along the western shore of the river above the mouth of the Conewago Creek diversion chamel that skirts the nortt.ern edge of the Brunner Island Plant site.
Station 7 This station was located between the northern tip of Halde=an (=Elliot) island and the eastern shore.
Station 8.
This station wac located along the western shore of the river about one mile below the discharge canal of the Brure.er Island Plant.
Station 9 This station was located at, the western edge of Haldeman Eiffle above the mouth of Codorus Creek.
1,;;0 0?9
.~
WATER QUALITY On August 20, 1968 one set of water samples was taken for water quality analyses. These analyses were perfor=ed by the laboratory personnel of the Pennsylvania Power & Light Ccmpany.
Results of these analyses, expressed as parts per m4'14cn, are presented in Table 1.
k TABLE 1 Water Quality Characteristics Station Methyl Orange Total Chlorides Suspended Alkalinit/
Hardness (as Nacl)
Matter (asCaCO)
(asCaCO) 3 3
1.
60.0 247.0 29 5 15 7 2.
42.0 249 0 25.5
-8 9 3
44.0 204 5 23.5 74 4.
48.0 135 0 21 5 10.4 6.
76.5 118 5 22.5 24.0 7.
58.0 193 5 24 5 17 0 8.
70.0 143.0 23.0 8.5 9
66.5 150.0 23 5 72 Water quality characteristics measured in the field included dissolved oxygen concentrations and temperature. These were measured August 20, 1968 coincident with the collection of the water samples taken for analysis. Table 2 presents the data from the field measurements.
){]0
\\
-3
TABLE 2 Dissolved Oxygen (ppm) and Temperature ( ?)
Station Tine Deptb Dissolved Temperature Oxygen 1'
1505 Surface 8.0 88.7 Bottom (3 ft.)
8.0 88 7 2
1450 Surface 8.5 82.4 Bottom (3 ft.)
85 81 5 3
1435 Surface 8.0 79.7 5 feet 8.0 78.8 Bottom (7 ft.)
8.0 78.8 4
1L25 Surface 7.5 80.6 5 feet 6.5 78.8 Bot. tom (7 feet) 6.5 78.8 6
13L5 Surface 8.0 85 1 7
1110 Surface 7.0 78.8 Bottom (3 ft.)
7.0 78.8 8
1030 Surface 5.5 93.2 Bottom (2 ft.)
55 93.2 9
0d35 Surface 55 83 3 During the time of the survey river flow was falling. Flow AuE.ist 12th was 6,500 cfs; August 20th, 5,200 cfs. Flows of less than 10,000 cfs had persisted in the river since July 21, 1968.
During the 12 days preceding the survey river ficw averaged 7,L90 cfs/ day. River flow for the 12 days preceding the 1967 survey averaged 19,590cfs/ day. Durdr.g the survey period river elevation ranged from 251.37 tc 251.65:
a range of 0.28 foot.
4
-u-
)
BIOLOGICAL COLLEC"'ICUS A total of 119 species of =acroinvertebrates was collected during the 1968 survey. During the 1967 survey a total of 145 species was collected frc= these eight stations. The species collected in 1968 are presented in Appendix A along dth their distribution a=cng the eight stations. Table 3 su==ar_4:es the 1967 and 1968 cc11ections.
TABIZ 3 Nu=bers of Macrcinvertebrate Species Station Non-Insects Insects Total
'67 '68
'67 '68 '67
'68 1
20 23 23 31 43 54 2
18 20 28 22 46 L2 3
19 15 16 12 35 27 4
20 13 28 13 L8 26 6
12 lh 44 2a 56 38 7
13 10 32 29 45 39 8
7 3
32 7
39 10 9
13 19 57 35 70 56 Six dcminant species (5% of the total) are recognized herein.
The first of these is a snail, Physa heterostropha, which was found at all eight stations. 3e re=aining five dc=inants were absent fres Station 8.
Sese latter five included a limpet, Ferr.d ssia tarda, a fingernail cla=, Sphaeriu= sp.1, a sludge worm, Li=nedrilus ef. hoffneisteri, and two =idge larvae, Polypedil.:n 1111ncense and Chirenc=us sp.1.. _,
-n 1
J iuL Ji
4 Of the 119 species collected, 52 (44%) occurred as urlque species, i.e., occurred at only ene of the eight stations. Of the 145 species taken at these stations in 1967 there were 53 (375) unique species found.
Easic descriptive statistics developed frem the biological data include the mena (E), standard deviation (s), variance (s ),
2 and the coefficient of variation (V). Table a presents these descriptive statistics for both 1967 and 1963.
TABLE 4 Descriptive Statistics 2
-x s
s V
1967 N.on-insects 15 L.72 22.29 31.5%
Insects 33 12.75 162.57 3a.6%
Total 48 10.93 119.13 22.e5 1968 Non-insects 15 6.31 39.e6 42.1%
Insects 22 10.05 101.29 L5.7%
Total 36 14.89 222.00 El.L%
It is apparent, frem Tables 3 and L that the biological structure of the study area differed appreciably between 1967 and 1968. The fever r"-ber of species fcund in 1968 along with a greater variance and higher coefficient of variation values reflect the differences.
A chi square analysis for ec= pari.g two sets of observed data was nade ec= paring the 1967 and 1968 collections. A chi ^~
g l '- eJ,qJ tu3
.~
square value of 19.93 was found with p=0.005-0.010.
This is statistically significant. A chi square test was also done comparing the insect fauna of 1967 with that of 1968. The derived chi square value was 18.59 with p=0.005-0.010, which is also statistically significant. A chi square test done to ec= pare the 1967 non-insect fauna with the 1968 ncn-insect fauna produced a chi square value of 5.44 with p=0 500-0 750.
Obviously, no significant difference occurred between these two collections.
Using rank order correlation analysis (Spear _.an rho) no correlation was found between the non-insects and insects for either 1967 (rho==-0.683) er 1968 (rhc=0.52i).
Correlation analyses were =ade c:= paring.the dist:"bution of organisms a=ong the stations for the two years. No correla-tien was found (rho =0 375) for the total nu=ber of species taken at the stations for 1967 versus 1968. Further, no correla-tion was found for the insects alone (rhc=0 393) er the non-insects alone (rho =0 5AS).
It is apparent that the chief difference between the 1967 and 1968 collections rests with the insect ec=panent of the fauna rather than the non-insect ec=ponent (Species 1-38 of Appendix A). 19 z1 iennJs'J tur
In 1967 river ficws were such that water cascaded over the spillway of the York Haven Dam. In 1968 low river flows pre-vented spillway loses, and releases to flew below the dam was affected through the York Haven R7 ro Plant. Co=parisons d
have been made between the group of four static'ns above the das and the four stations below the dam. These two groups are Stations 1-4 and Stations 6-9 respectively. In 1967 no t
significant difference was found (chi square =2.26; p=0 500-0 750) between these two groups of stations. In 1968, hcwever, a significant difference was found (chi square =20 30; p= t0.005).
This change in biological structure is associated with a reduced diversity in the insect fauna. Table 5 presents the descriptive statistics for the above-dam and below-dam station groups.
TABIZ 5 Descriptive Statistics Above Dam,1967 2
I s
s 7
Non-insects 19 1.00 1.00 0.05%
Insects 24 5.68 32 53 23.7%
All species 43 5 71 52.66 13 3%
Above Dam, 1968 Non-insects 18 4 58 21.00 25 4%
Insects 20 8.91 79 33 44.6%
All species 37 13 35 178 33 36.1%
)J.d IJ
TABI2 5, cent'd.
Selow Dam, 1967 ic s
s 7
Non-insects 11 2.88 8.33 26.2%
Insects 41 11.80 139 33 28.8%
All species 56 14.21 202.00 25.L%
Below Dam, 1968 Non-insects 12 6.97 48.67 58.1%
Insects 24 12.04 145.00 50.2%
All species 35 18.36 337.00 52.5%
The sharply increased variance (s ) of 1968 over 1967 is very striking. This, of course, reflects the greater diversity among the stations sampled. The increased coefficient of variation (V) reflects a loss cf biological stability and the resident fauna was apparently in a state of flux during the 1968 survey.
The biological structure of the river found in 1968 reflects environmental influences not present in 1967 These influences were widespread, extending from above the York Haven Dam down-stream to Haldeman Riffle. These influences could be considered as adverse for the ecmmunity of species characteristic of the river in 1967 since there was an 18% reduction in species diversity between 1967 and 1968.
It is suggested here that one of the chief environmental influences exerted during 1968 was the continuous low flow con-ditions of the river during 1968.
}h With low-flew conditions the securing of substrate material is much reduced. This permits the deposition of silt, which is physically limiting to many bottom organisms. In addition, continuous low ficw would severely linit the transpcrt and diotribution of organisme. Low flew conditions would also permit stronger local effects from discharges entering the river. For example, the discharge from the Brunner Island Plant would more centinuously inundate Station 8, which is in the mixing :ene. At the time of this survey, however, lethal te=peratures were not found at Staticn 8. Reference to Table 2 shows that en August 20, 1968 there was a ten-degree drop between Stations 8 and 9, indicating that the west end,af Haldeman Riffle is not subject to abnormally high temperatures that would be biologically licdting. Station 9 had the same diversity (5A species) found at Station 1 above Three=ile Island. Some field observations seemed to indicate a recent toxic affect in the river. For example, at Statien 4 on August 14th numerous unienid clu:s (Anodonta cataracta) were found dead. A few of these had died so recently that muscle tissue was still attached to the inner surface of the shell valves. Such tissues usually deccepose within a few days after death. ~ G 1^7 I / U io/ J
Statiens 2 through 4, located in the pool of the York Haven Dam, had sc=e oil or oil-like substance entrained in bottem materials. The exact nature of this caterial, and its extent over the bottom of the pcol, was not investigated. Extensive stands of rcoted aquatic vegetation indicated that much of the bottem was not affected by this caterial. ib/b b,
e = APPDIDIX A n Y l
APPENDII A PACROINVERTEEPAIS SPECI"3 Stations 1 2 3 h 6 7 8 9 FIATWCRMS
- 1. Dugesia tigrina x x x x x
- 2. Prestoma rubrum x
x SPONGE
- 3. Spongillidae g. sp. 1 x
'dCRP2 L. Ihnodrilus ef. hoffmeisteri x x x x x x x
- 5. Tubifex sp. 1 x
- 6. Branchiura sowerby1 x
- 7. Lumbriculidae g. sp. 1 x
x
- 8. Lumbriculidae g. sp. 2 x
- 9. Megsscolecidae g sp. 1 x
x x
- 10. Megadriline x
LEECHES
- 11. Helebdella nepheloidea x x x
12..Placobdella rugosa x x x
- 13. Placobdella parasitica x
x
- 14. Erpobdella punctata x x ERYOZCAIS
- 15. Plunmatella repens x x x x x x
- 16. Paludicella articulata x
- 17. Urnatella gracilis x
x x x
- 18. Lophopodella carteri x x x
x CLAMS
- 19. Sphaerium sp. 1 x x x x x x x
- 20. Pisidium sp. 1 x x x x x
- 21. 711dptio complanata x
x
- 22. Anodonta cataracta x
- 23. I= mature unionids x x x. 3 a J
, v
Stations 1 2 3 4 6 7 8 9 SNAILS
- 24. Campelema integrum x
x x
- 25. Amnicola ef. limosa x x x x x
- 26. Gonicbasis virginica x x x x
- 27. Nitocris carinata x
- 28. Physa heterostropha x x x x x x x x
- 29. Ferrissia ef. tarda x x x x x x x
- 30. Helisema ef. trivolvis x
x x x
- 31. Gyraulus sp. 1 x
x x
- 32. Gyraulus sp. 2 x
- 33. Lymnaea humilus x
x x x CRAYFISH
- 34. Creenectes sp. 1 x
x x SCWBUG
- 35. Asellus cem=unis x
SCUDS
- 36. Hyalella a::teca x
- 37. Gammarus fasciatus x x x
.x
- 33. Crtngenyx gracilis x
MAlTLIES
- 39. Eexagenia sp. 1 x x 40,. Stenene=a sp. 1 x
x x x
- 41. Steneneca sp. 2 x x x x x x
- 42. Stenenema sp. 3 x
- 43. Stenenema sp. A x
x
- 44. Stenenema sp. 5 x
x x x
- 45. Isonychia sp. 1 x
- 46. Tricorythodes sp. 3 x
x
- 47. Tricorythedes s;i. 6 x
- 48. Caenis sp. 1 x
- 49. Caenis sp. A x
- 50. Pseudociceen sp. 2 x
- 51. Baetinae g. sp. 1 x
DRAGONFLIIS
- 52. Ocmphus sp; 1 x
x
- 53. Gemphus sp. 2 x
- 54. Ecyeria sp. 1 x
- 55. Macremia sp. 1 x 4 a
,s n lb/J II
Stations 1 2 3 4 6 7 8 9 DAMSELFLIES
- 56. Argia sp. 1 x
x x x
- 57. Enallagma sp. 1 x
- 58. Enallagma sp. 5 x x x
- 59. Enallagma sp. 6 x
- 60. Enallagma sp. 7 x
- 61. Ischnura sp. 1 x x x
- 62. Ischnura sp. 4 x
x
- 63. Hetaerina sp. 1 x x WATER STRIDERS AND WATER BUGS
- 64. Gerris sp. 1 x
x
- 65. Metrobates sp. 1 x
- 66. Trepobates sp. 1 a
x
- 67. Trepobates sp. 2 x x x x
- 68. Trepobates sp. 3 x x
- 69. Rheumatobates sp. 1 x
- 70. Mesovelia ef. mulsanti x x x x x x
- 71. Nepa apiculata x
- 72. Corixinae g. sp. 1 x
- 73. Hemiptera fam. g. sp.1 x
r. CADDISFLIES 743 Hydropsyche sp. 1 x x x x x x
- 75. Hydropsyche sp. 2 x
- 76. Psychomyia sp. 1 x
x x
- 77. Fam. g. sp. 1 x
x LARVAL EEETLES
- 78. Berosus sp. 1 x
- 79. Elmidae g. sp. 2 x
- 80. Eubrianax sp. 1 x
ADULT EEETLE3
- 81. Berosinae g. sp..
x x
- 82. Hydrochus sp. 1 x x x x x x
- 83. Tropisternus sp. 2 x
- 84. Laccophilus sp. 1 x
- 85. Stenelmis sp. 1 x
- 86. Stenelmis sp. 2 x
- 87. Stenelmis sp. 3 x
x
- 88. Stenelmis sp. 4 x x x
- 89. Stenelmis sp. 5 x
- 90. Stenelmis sp. 7 x
-111-a 3IL } ;,,. o U i
Stations 1 2 3 4 6 7 8 9 ADULT EETLES, cont'd.
- 91. cf. Peolono=us sp. 1 x
- 92. ef. Pelonomus sp. 2 x
x x x
- 93. Gyrinus sp. 1 x
- 94. ef. Anthicidae g. sp. 1 x
- 95. Curculionidae g. sp. 1 x
DANCEFLY
- 96. Empididae g. sp. 1 x
MIDGE LARVAE
- 97. Procladius sp. 1 x
x
- 98. Tanypus sp. 1 x
- 99. Conchapelopia sp. 1 x
100. Ablabesmyia mallochi x x x x x 101. Ablabcemyia auriensis x x 102. Ablabesmyia ornata x 103. Labrundia virescens x 104. Cricotopus sp. 2 (Roback) x 105. Nanocladius sp. 1 x x 106. Polypedilum 4714ncense x x x x x x x 107. Polypedilum sp. 1 x x 108. Polypedilum halterale x x x 109. Cryptochironomus fulvus x x x x 110. Cryptochironotus blarina x x 111. Cryptochironomus sexew x 112. Dierotendipes nervosus x 113. Dicretendipes nr. neomodestus x x x 114. Dicrotendipes sp. 1 x x x x 115. Glyptotendipes lobiferus x x 116. Chironomus sp. 1 x x x x x x x 117. Chironomus sp. 2 x 118. Rheotanytarsus sp. 1 x x x 119. Chironominae g. sp. 1 x [) J/V -iv- .}}