quC'CS LIBRARY ,, Michigan Sara University I i This is to certify that the thesis entitled SEASONAL SUCCESSION OF CLADOCERAN SPECIES IN THREE TEMPORARY PONDS IN SOUTHERN MICHIGAN presented by Bette J. Premo has been accepted towards fulfillment of the requirements for Masters . Science degree in Major professor ,//- M f? 0-7639 OVERDUE FINES: 25¢ per day per item RETURNING LIBRARY MATERIALS: Place in book return to name charge from c1 mutation record SEASONAL SUCCESSION 0F CLADOCERAN SPECIES IN THREE TEMPORARY PONDS IN SOUTHERN MICHIGAN By Bette J. Premo A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Zoology 1980 ABSTRACT SEASONAL SUCCESSION 0F CLADOCERAN SPECIES IN THREE TEMPORARY PONDS IN SOUTHERN MICHIGAN 3y Bette J. Premo Three temporary ponds in southern Michigan were studied to observe the seasonal succession of cladoceran species. Weekly sampling was conducted from April through August, 1979, and April through June, 1980. Measurements taken include water pH, dissolved oxygen, maximum and minimum water temperature and suspended particulates within clado- ceran food size range. In Toumey pond, five species (five genera) of Cladocera were collected in 1979, four species (four genera) in 1980. In Upton pond, two species (two genera) were collected in 1979, and three species (three genera) in 1980. Six cladoceran species (five genera) were collected in Oak pond, in 1979, five species (four genera) in 1980. water pH ranged from 6-8 and dissolved oxygen from 1-12 mg 02/L. Fluctuations in density of suspended particulates were compared to changes in water temperature and cladoceran species’ density, mean length and clutch size. Water temperature was examined as a factor which may influence population dynamics of cladocerans. ACKNOWLEDGMENTS I wish to thank the members of my guidance committee, Dr. T. w. Porter and Dr. R. J. Snider from the Department of Zoology and Dr. C. D. McNabb from the Department of Fisheries and Wildlife for their contri- bution in the development of my project and completion of this manu- script. Special appreciation is due my major professor, Dr. T. w. Porter, for his enthusiasm and love for biology greatly inspired me during the past two and one-half years. His conscientious scrutiny has sharpened my scientific skills. I thank my husband, Dean, for constructing tables and figures and his help in field work and editing of this thesis. 1'1 TABLE OF CONTENTS jggg; LIST OF TABLES ........................ iv LIST OF FIGURES ....................... v INTRODUCTION ......................... 1 METHODS AND MATERIALS .................... 4 DESCRIPTION OF STUDY AREAS ............... 4 FIELD PROCEDURES .................... 8 LABORATORY PROCEDURES .................. 9 RESULTS AND DISCUSSION .................... 12 PHYSICAL PARAMETERS ................... 12 CLADOCERA IN THE THREE PONDS .............. 15 THE OCCURRENCE OF OTHER INVERTEBRATES .......... 30 THE EFFECTS OF TEMPERATURE ON CLADOCERAN POPULATION DYNAMICS ........................ 31 SPECULATIONS FOR FURTHER STUDY ............. 39 SUMMARY AND CONCLUSIONS ................... 41 LITERATURE CITED ....................... 43 APPENDIX ........................... 46 Table A1 A2 A3 A4 A5 A6 A7 A8 LIST OF TABLES List of cladoceran species collected in Toumey, Upton and Oak ponds, 1979 and 1980 .............. Weekly pH, dissolved oxygen, particulates, spectro- photometric absorbance, and max-min water temperatures of Toumey, Upton and Oak ponds, 1979 .......... Weekly pH, dissolved oxygen, and max-min water tempera- tures of Toumey, Upton, and Oak Ponds, 1980 ...... Weekly net gain or net loss in number of Daphnia pulex and Ceriodaphnia spp, per 100 liters in Toumey, Upton, and Oak ponds, 1979 ............... Weekly net gain or net loss in number of Daphnia pulex and Ceriodaphnia 358, per 100 liters in Toumey, l ............... Upton, and Oak ponds, Weekly per capita gain or loss for Daphnia pulex and Ceriodaphnia Spp. per 100 liters in Toumey, Upton, and Oak ponds, 1979 ............... Weekly per capita gain or loss for Daphnia pulex and Ceriodaphnia ggp, per 100 liters in Toumey, Upton, 9 .................. and Oak ponds,'l Weekly specific growth rates of Daphnia pulex and Ceriodaphnia spp. and weekly mean temperatures in ‘TOUmey, Upton and Oak ponds, 1979 ........... Weekly specific growth rates of Daphnia pulex and Ceriodaphnia spp. and weekly mean temperatures in TOUmey, Upton, and Oak ponds, 1980 ........... iv Page 16 46 49 50 51 52 54 LIST OF FIGURES M 2222 1 Morphometric map of Toumey pond ............ 5 2 Morphometric map of Upton pond ............ 6 3 Morphometric map of Oak pond ............. 7 4 Daphnia pulex ..................... 18 5 Relationship between carapace length and Clutch size of Daphnia pulex in three temporary ponds ....... l9 6 Simocephalus vetulus and Ceriodaphnia quadrangula . . . 23 7 Scapholeberis kingii and Chydorus sphaericus ..... 25 8 Daphnia rosea and Ceriodaphnia reticulata ....... 29 9 Weekly maximum temperatures and density estimates of Daphnia pulex and Ceriodaphnia spp. in Oak, Toumey and Upton ponds, 1979 ................. 33 10 Exponential population growth (from Pianka, 1978) . . . 36 11 Relationship between weekly mean water temperatures and specific growth rates of Daphnia pulex and Ceriodaphnia spp .................... 37 A1 Temporal changes in total number of Cladocera and particulate density in Toumey pond, 1979 ....... 55 A2 Temporal changes in total number Of Cladocera and particulate density in Upton pond, 1979 ........ 56 A3 Temporal changes in total number of Cladocera and particulate density in Oak pond, 1979 ......... 57 A4 Weekly density estimates of cladoceran Species in Toumey pond, 1979 ................... 58 A5 Weekly density estimates of cladoceran species in Toumey pond, 1980 ................... 59 V LIST OF FIGURES (Continued) Figure Page A6 Size distribution of Daphnia pulex in Toumey pond, 1979 ...................... 60 A7 Size distribution of Daphnia pulex in Toumey pond, 1980 ...................... 61 A8 Size distribution of Daphnia pulex in Upton pond, 1979 ...................... 62 A9 Size distribution of Daphnia pulex in Upton pond, 1980 ...................... 63 A10 Size distribution of Daphnia pulex in Oak pond, 1979 ......................... 64 All Size distribution of Daphnia pulex in Oak pond, 1980 ......................... 65 A12 Weekly density estimates of Cladocera species in Upton pond, 1979 ............. ‘ ...... 66 A13 Weekly density estimates of Cladocera species in Upton pond, 1980 ................... 67 A14 Weekly density estimates of Cladocera Species in Oak pond, 1979 .................... 68 A15 Weekly density estimates of Cladocera species in Oak pond, 1980 .................... 69 vi INTRODUCTION Members of the Order Cladocera, commonly called water fleas, are small aquatic filter feeders belonging to the Class Eucrustacea. Cla- doceranS have long been popular laboratory and field study animals, but few investigations have conclusively determined the factors affect- ing cladoceran population dynamics under natural conditions. The Objective of this study was to follow the seasonal succession of cladoceran Species in three temporary ponds in the Greater Lansing Area. Water temperature, pH, dissolved oxygen, and suspended parti- culates were measured to determine if relationships existed between these factors, seasonal succession and abundance of cladocerans. Field sampling was conducted during April through August 1979 and April through June 1980. Early workers believed fluctuations in water temperature, water level, dissolved oxygen and inorganic substances directly controlled abundance of microcrustacea. Kenk (1949) conducted an extensive study of invertebrate animal life in ponds of southern Michigan. He related the physical and chemical characteristics of a pond to the seasonal abundance Of each species present. Ward (1939), in her study of pond Eucrustacea, measured carbonates, pH, water tempera- ture, dissolved oxygen, and water level, but found temperature to be the most important Single factor in controlling populations. The 2 importance of temperature has been reported by other workers (Birge, 1898; Brown, 1929; Petersen, 1926). Recent studies have related physical parameters to physiological responses Of cladocerans and subsequent effects on population growth. Kring and O'Brien (1976a) found that maximal feeding rates of clado- cerans can be altered by Changes in pH. However, they Observed Daphnia pglgx_Leydig to resume maximal feeding rate after its initial response of depression. Kring and O‘Brien (1976b) found dissolved oxygen concentrations Of less than 3 mg/liter lower 9; pglgx filtering rate. However, after prolonged exposure, L 31135 was able to increase and resume normal filtering rates. Several investigators contend that algae is an important form of food for zooplankton and they correlate fluctuations in algal growth with changes in cladoceran population size (Fischer, 1970; Ingle, Wood, and Banta, 1937). Others argue that it is difficult to measure the quantity of food available to these filter feeders because cladocerans have many sources of nutrition including algae, detritus, bacteria, dissolved organic matter, and inorganic matter (Edmondson, 1957; Glicwicz, 1969; Jorgensen, 1962; Kryuchkova and Rybak, 1976, Lampert, 1974; Parlyutin, 1976; Rodina, 1947; Weglenska, 1971). Competition between species of cladocerans may play an important role in controlling populations as Shown by Lynch (1978) and Neill (1975). Predation by both invertebrate (copepods, aquatic insects) and vertebrates (fish, salamanders) may also effect cladoceran popu- lation size (Brooks, 1968; Brooks and Dodson, 1965). 3 In this study, each cladoceran species collected was examined in terms of its adaptations to a selected pond environment. The role of water temperature was given special attention in seasonal succession. Other parameters investigated were pH, dissolved oxygen and, within their Size range for food, suspended particulates. METHODS AND MATERIALS DESCRIPTION OF STUDY AREAS The three ponds studied can all be considered temporary ponds. They typically contain water throughout spring and early summer (15 to 20 weeks) and are dry for the remainder of the year. Toumey pond is located south of Michigan State University campus, East Lansing, Ingham County, Michigan (T4N:R1W:S30). This pond is in Toumey Woodlot, a mature beech-maple hardwoods. Upton pond is located at the southeast corner of Upton and Clark Roads in an area called the rabbit enclosure Of Rose Lake Wildlife Area, Clinton County, Michigan (TSN:R1W:523). Upton pond is located in an open field area with a few living Poplar (Populus deltoides) trees on its banks. Oak pond is in the northeast corner of Rose Lake Wildlife Area, Shiawasee County, Michigan (T5N:R1E: $21) and is surrounded by oak and maple. Morphometric maps made during the mid-wet season, 1979, of Toumey, Upton and Oak ponds are presented in Figures 1, 2, and 3, respectively. These temporary ponds are perched sealed basins lined by glacial till consisting mostly of clay (Prouty, 1980). The ponds collect spring rain and run-off which evaporates Slowly during a period of approximately twenty weeks. In 1979 and 1980, when snow melt and rains began to fill the ponds during late March and early April, sampling was initiated and continued on a weekly basis. EU unom Amazes Mo an: ownvosonmnos .mhsopcoo ummumsnsm . mpwwoe 0a . .madom am. 0 SE .H ousmam coed mmh< om canon Enamxms am zeta: Edeflxms on newcoa ESwamz 020m sown: mo am: ownposonnhos .N ohsmflm Eo «mhzopcoo comumensm . myopoe oH . .oamom ( NE oomH mou< Eo om canon asawxms E mm can“: Esswxms s.ow newcma aseflxmz ccom ado no an: cappososmnos .m ohsmflm Eo .mhsopcoo ummhmensw mhmpme om «madam NE wmom amh< so 20 canon asawxmz a m: zeta: assaxms 8 :0H newsma Esefixms FIELD PROCEDURES In 1979 samples of the water column were taken to determine the density of suspended particulate substances of the appropriate food size range for cladocerans. A two inch diameter plexiglass tube, three feet in length, was placed vertically in the water to within 10 cm of the bottom. A stopper was placed in the tube and the total water column sample was placed in a jar for subsequent laboratory analysis. Six water column samples were taken at randomly chosen locations in each pond during each sampling period. A random numbers table (Brower and Zar, 1977) was used to select sample locations from a pond map divided into numbered square meters. Air and water temperatures were recorded on each sampling date using a Yellow Springs Instrument telethermometer. Water pH was determined with a Fisher-Accumet Portable Model 150 pH Meter. A Hach Kit provided weekly in-field estimates of dissolved oxygen. Water temperature, dissolved oxygen, and pH were measured at depths of approximately 50 cm. Maximum and minimum water temperatures between sampling dates were measured with Taylor thermometers which were secured to bricks with elastic and placed at approximately 50 cm depth in each pond. Literature review and personal field trials of various plankton collecting devices indicated that a small tow net best insured the collection of the cladoceran species and allowed reasonably quantitative analysis. A 10 cm diameter tow net was used in 1979, but was not available in 1980. In 1980, a 12 cm diameter Wisconsin plankton net was used. A one meter sweep of the net taken in 2-3 seconds constituted one sample. Five such samples were collected 9 per pond, per weekly sampling period. Organisms were immediately preserved with 95% ethanol and brought back to the laboratory and stained with eosin. During May, 1979, depth measurements were taken to construct contour maps of the three ponds. A line transect was staked along the long axis of a pond and depth was measured every four meters along this transect. Transects perpendicular to the main line were run at intervals and depth was measured every four meters. Distances and depths were plotted. LABORATORY PROCEDURES Immediately after field sampling, water column samples were analyzed in the laboratory. Water was first passed through consecu- tively finer series of three Fisher "mesh" series sieves (Size 60, 100, and 200) which removed the particulate material greater than 70 pm diameter. Filtrate was placed in a beaker and magnetically stirred, evenly suspending the remaining particulates. Fifty milli- liters of filtrate were drawn into a Plastipak disposable 100 cc syringe. Onto this syringe was placed a Swinnix-25 filter unit con- taining a 25 mm diameter piece Of Millipore filter paper (0.45 um pore size). The filtrate was forced through the unit and the filter paper collected particles in the filtrate greater than 0.45 pm diameter. These pre-weighed filters were then oven dried and weighed on a Mettler balance to estimate the weight in milligrams of 0.45 to 70 um diameter particulates in 50 m1 Of water. This is the estimated food Size range for most cladocerans (Burns, 1968). Two subsamples of 50 cc in each of six water samples per pond were processed in this manner. 10 Preliminary trial of this technique revealed that filter papers lost weight when water was forced through them. To minimize this all filters were pre-treated by forcing 50 ml of distilled water through them before being dried and weighed. It was of interest to determine whether the amount of particulate material was correlated to the amount of chlorophyll containing parti- cles (algae) in the water column samples. To determine this a Beckman Spectrophotometer (Model 20) was used and absorbance in the range Of 665 mu (absorbance range for Chlorophyll a) was measured. Spectro- photometric readings were performed on sieved water samples both before and after Millipore filtering. The difference between these values is an estimate of the amount Of Chlorophyll containing particles in the 0.45 to 70 um range. Weekly fluctuations in chlorophyll values were examined in relation to weekly fluctuations in particulate density. To estimate the relative numbers of cladocerans present each sample was evenly distributed onto a petri dish marked with a grid Of 63.5 numbered squares. In the majority of collections all clado- cerans were counted in a completed one meter tow. When samples con- tained approximately 6000 or more Cladocerans, the total number of cladocerans in ten randomly chosen squares was multiplied by 6.35 to estimate numbers in the entire sample. A table of random numbers was used to make random grid square selections (Brower and Zar, 1977). A performance curve (Brower and Zar, 1977) was used to determine that ten subsamples best estimated the mean density. A11 enumerated cladocerans were treated with glycerin which cleared them and facilitated identification. Cladocerans were iden- tified to species and sexed according to Edmondson (1959) and 11 Brooks (1957). Total carapace length was measured to the nearest 0.1 mm using an ocular micrometer as described by Anderson, et a1. (1937). Eggs of gravid females were counted and presence of ephippia noted. RESULTS AND DISCUSSION PHYSICAL PARAMETERS In 1979, all three ponds filled with water during April, but the length of their wet season varied. Toumey pond contained water until late August, Oak pond until mid-August, and Upton pond until mid-July. The deepest pond was Toumey at 90 cm, with surface area of 1100 m2 (Figure l). Upton pond had a surface area of 1300 m2 and maximum depth of 60 cm (Figure 2). The largest pond was Oak pond with a surface area of 2976 m2 and a maximum depth of 64 cm (Figure 3). Near the end of the wet season, water levels became very low and only scattered puddles remained. In 1980 all the ponds began to fill after a thaw in March. Water pH showed little variation over the entire wet seasons Of 1979 and 1980 (Tables Al and A2). In 1979, Toumey pond ranged from 6.5 to 8.0, with mean pH of 7.1 (95% confidence interval 6.85, 7.35); Upton pond from 7.1 to 8.5, with mean of 7.3 (95% C.I. 7.0,7.6) and Oak pond from 6.0 to 7.5, with a mean pH of 6.8 (95% C.I. 6.6.7.0). In 1980, Toumey pond pH ranged from 6 to 7.4, with mean of 7.0 (95% C.I. 6.7,7.3); Upton pond from 6.0 to 7.4 with mean 6.6 (95% C.I. 6.2.7.0) and Oak pond from 6.1 to 7.0 with mean of 6.6 (95% C.I. 6.3,7.0). All cladoceran species encountered in the ponds were phy- siologically suited to accommodate pH levels Observed (Kring and . O'Brien, 1976a). 12 13 Greatest dissolved oxygen concentration (00) was observed in the three ponds during the early season of 1979 and 1980 when water temperature was lowest (Tables Al and A2). In Toumey pond DO concen- trations were highest during the second week of April, 1979 at 12 mg OZ/L‘ The lowest 00 concentrations in Toumey pond were measured during the final weeks of August 1979 at less than 1 mg Oz/L. During 1979 00 concentrations in Upton pond ranged from 11.5 mg Oz/L to 6 mg OZ/L and in Oak pond from 7.5 to 3 mg Oz/L. Dissolved oxygen concentrations of less than 3 mg OZ/L approach stressful conditions for most aquatic invertebrates (Lind, 1979). In 1979 and 1980 this low level was not Observed in Upton pond. In 1979, cladoceran populations were much reduced in Toumey pond when dissolved oxygen concentrations reached 1-2 mg OZ/L' During the 1980 field observations, Toumey pond 00 remained above these low levels. Interestingly, Oak pond populations of Daphnia rosea Sars and Ceriodaphnia reticulata (Jurine) were high when the dissolved oxygen was only 3 mg OZ/L' These species may be suited to this environment. Some daphnid Species increase their reproductive rates in environments with low dissolved oxygen. This may be associated with their ability to produce hemo- globin and overcome the low oxygen tension (Kring and O'Brien, 1976b). Water temperatures varied in the ponds over both 1979 and 1980 seasons (Tables Al and A2). Maximum temperatures in these Shallow ponds reached levels not experienced in more permanent bodies Of water. The effect of temperature will be discussed in a later section. Weight in milligrams per liter of suspended particulates within the size range 0.45 to 70 um was measured to estimate the amount . of food available to cladocerans. Particles within this size range 14 are filterable by adult Daphnia ggg. and Simocephalus spp. Juvenile Daphnia spp. and smaller species such as Ceriodaphnia spp., Scaphole- beris kingii Sars and Chydorus sphaericus (O.F.M.) most efficiently filter particles in the lower end of this size range (Burns, 1968). Cladocerans feed on algae, bacteria, yeasts, organic aggregates, dead plant and animal material and inorganic particles (Jorgensen, 1962). Therefore any method of estimating available food measuring only algal particles would not adequately express total amounts of food available. Particulate densities varied in the ponds during both seasons. In all three ponds, particulate density was low in early season (approximately 1 mg/L) and increased as the season pro- gressed, but showed some fluctuation (Figures Al, A2, A3). There is a significant positive correlation (95% level of Signi- ficance) between water temperature and particulates in Toumey pond, Oak pond and the data from all three ponds combined. This relation- ship does not necessarily reflect causation, but water temperature increase has been shown to increase phytoplankton production rate (Foerster et al., 1974) and could be a reason for the relatively high correlation. Particulate density was not correlated with any one species' population density, species' mean length or clutch size in any pond. Figures Al, A2 and A3 illustrate changes in particulate density and numbers of all cladoceran species in the ponds in 1979. NO signifi- cant correlation between these parameters was found, which may indicate that grazing pressure by the filter feeders had no measurable effect on the amount of food available. No significant correlation was . observed between particulate density and chlorophyll spectrophotometric 15 absorbance (95% or 90% level of significance) in Toumey or Upton ponds and there was no correlation (95% or 90% significance) in data from all three ponds combined. This may indicate that suspended particulates were composed of other particles as well as chlorophyll containing materials. CLADOCERA IN THE THREE PONDS All genera and Species of cladocerans collected in the three ponds in 1979 and 1980 are presented in Table 1. Five species of Cladocerans were collected in Toumey pond during 1979 (Figure A4). The earliest species to occur were Daphnia pulex Leydig. ‘0; gglgx from Toumey pond were 0.5 to 3.5 mm long. The eyes and ocelli were large and the head had a broadly rounded anterior margin and concave ventral margin terminating in a pointed rostrum (Figure 4). Valves were ovate and ended in a tail spine that was usually less than one quarter of body length. The identifying feature of this Species was the number of posterior toothlike processes called pecten located on the anal claw. Q; pglgx_have stout middle pecten, that usually number 5-7 (Brooks, 1957), and this is illustrated in Figure 4F. The mature parthenogenetic female carries eggs in a dorsal brood pouch. Egg number varies from 2 to 60 depending on the length of the female and environmental conditions (Anderson, et al., 1937; Lampert, 1978). Figure 5 illustrates the relationship between the length and Clutch Size of Q; gglex_from all three ponds in 1979 and 1980. Figures A6-All Show the percent 0f.QE.E!l§§ in each of eleven arbitrarily assigned size Classes, in each pond during 1979 and 1980. 16 x N N P——--—————-_-—-d X x --——————_—————-—_-4 HARDER-q 3% 3% gang 3% a? CS gm .3ng omma mmma ccom xmc ommfi mum“ 38m Gown: on? 3.3 ocom Amazon. mmaoomm cahooocwdo .83 and 2.2 .mucom zoo and .223: 563309 a“ copooaaoo monomnm ”8.300698 .H 0.33. 17 Figure 4. Ibphni pule . A. gravid female B. male C. female with ephippium D. postabdomen 19 p.70 -—60 o O O O l o o O 00 m m I o o m o 00 oo o o m m o o o omoomoomoooomo O l 0000 m 00 mo 0 O O O O O ammo 8° 00 o 1 O 0 0&0 Wmme O 00 Gowm O O o mmoooo o D 00 o 3 . . . a 008m wm a mo w 00 o I mo 0 0 mac. 0 O a r 0 no no no no no 0 4, .fi 1, . 9. 1. O . — . . _ b _ . _ . _ 2.5 3.0 2.0 Carapace length (mm) 1.5 1.0 Ammwo ho hmnascv ouwm nopsao Figure 5. gth and pulex in three Relationship between carapace len clutch size of Daphnia temporary ponds. 20 Mature adults constitute the Size Classes greater than 1.5 mm long. Examining these figures, it is possible to follow a cohort of individ- uals from week to week as they increase in size, but this phenomenon may be obscured by succeeding hatches. Size distributions skewed toward smaller individuals often coincided with a peak in population density. Only sexually reproducing females carry two overwintering eggs in a darkened dorsal structure called an ephippium (Figure 4C). Both the parthenogenetic eggs and ephippium are released during molting. §L_gglgx undergo 18 to 25 molts depending on temperature and other environmental factors (Anderson et al., 1937; Weglenska, 1971). Over- wintering eggs are fertilized by male 0; gglgx. Brooks (1959) reported that mature males are characterized by being much smaller than mature females (0.75 to 1.25 mm) with a small truncated rostrum and long curved antennules (Figure 48). Males in Toumey pond were usually found just before, or simultaneously with, ephippiated females. In 1979, large numbers of males were collected on April 12 and April 20 in Oak pond, with no subsequent collection of ephippiated females. The reason for this occurrence remains unclear. Male Dg_gglg§_repre- sented no more than 5% of the total population at any one time. Ephippiated females represented up to 30% of the total population when Dg_gglg§ densities were rapidly decreasing. During May 1-10, 1979, Ceriodaphnia quandrangula (O.F.M.) and Simocephalus vetulus Schddler appeared in Toumey pond (Figure A4). The genus Ceriodaphnia belongs to the family Daphnidae, as does 0; gulex. Edmondson (1959) describes the general form of Ceriodaphnia g.§gg. as rounded or oval, and small in size, rarely exceeding 1 mm 21 in length (Figure 60). These animals have a large eye and a very short carapace spine or none. A rostrum is lacking. Ceriodaphnia quadran- .gglg (O.F.M.) has reticulated valves and the post-abdomen narrows toward the apex where there are claws with no pecten and anal spines which number 7-9 (Edmondson, 1959). In this study, 3, qu_adrangula at- tained lengths of 1.0 mm. The maximum number of eggs found in the brood pouch of mature female Q; quadrangula was four, and in sexually reproducing females there was only one egg in each ephippium. Simocephalus vetulus Schddler, which occurred concurrently with ‘9; quadrangula in Toumey pond, is also a member of the family Daphnidae (Edmondson, 1959). This genus is characterized by a large and heavy body, thick shell, small head and rostrum, large quadrate shaped values and a large post-abdomen which bears straight large claws (Edmondson, 1959). Figures 6A and 6B illustrate these Characters. ‘S; vetulus has a large, elongate ocellus and no spine on the valves in the populations studied. This species is typical of weedy water and usually attaches to vegetation by means of dorsal "sticky" head glands and gleans particulates from macrophytes (Green, 1919). In Toumey pond, §g_vetulus lengths ranged from 0.5 to 3.0 mm and mature females had clutch size range of 2-32 eggs. Only one overwintering egg was contained per ephippium. During the May 10, 1979 sampling period, Scapholeberis kingii Sars was Observed in Toumey pond. These small members of the family Daph- nidae have straight posterior and ventral margins with the latter extended into a point or spine (Figure 7A). .§;.kiggii has a black appearance, and very small antennules set behind a beak. The post- abdomen is short and broad. Carapace lengths in Toumey ranged from 22 Figure 6. Simocephalus vetulus and Ceriodaphnia Quadrangula. A. gravid §. vetulus female B. §. vetulus postabdomen C. Q. guadrangula postabdomen D. gravid Q. guadrangula female 24 Figure 7. Scapholeberis kingii and Chydorus sphaericus. A. grayid §. kingii female B. grayid Q. sphaericus female 26 0.2 to 0.7 mm. Female clutch sizes ranged from 1-4 eggs. Edmondson (1959) states this Species is common in pools and lakes in weedy water; however, their relative numbers remained low in Toumey pond (Figure A4). The last species to appear in Toumey pond was Chydorus sphaericus (O.F.M.). These were observed first on May 23, 1979. These, as all members of the family Chydoridae, have fornices that extend to cover the antennules and unite with the rostrum into a ventrally projecting beak (Edmondson, 1959). Figure 78 illustrates these characters. §;_sphaericus has a post-abdomen with 8-9 marginal den- ticles and a very small claw. This species ranged in length from 0.2 to 0.6 mm in Toumey pond and usually females carried two eggs, although up to four eggs were observed in some females. Edmondson (1959) states this is the most common of all cladocerans and have worldwide distribution. During the last weeks of August, 1979, Q; quadrangula, S; vetulus, and E; sphaericus were still present, but their numbers were decreasing and some individuals Of each species were producing ephippia. During the first ten weeks of the wet season in 1980, Toumey pond had all of the species as in 1979 except §;.Eiflflil (Figure A5). §L_gglg§_was observed in the pond first on April 12 and was the only species present at this time. §g_quadrangula appeared on April 20. On May 13, 1980, §g_vetulus and g; sphaericus were collected in Toumey pond. Population numbers fluctuated as shown in Figure A5. During the 1979 season, only Qg_pglg§_and S; vetulus were col- lected in Upton pond (Figure A12). On April 6, 1979, Q; gglgx was the only species collected. Its population rose and fell and by 27 May 31, 1979, Dg_pglgx never occurred again. On May 9, 1979’.§; vetulus appeared and its population peaked twice (Figure A12). After June 19, 1979’.§; vetulus was not seen again until the following spring. In 1980 during the ten weeks of sampling 0; 22125 was in Upton pond by April 5. During this year, Q; reticulata and S; kingii were also collected in Upton pond (Figure A13). They first appeared on May 14, 1980, and remained in the pond until sampling was terminated on June 20. In Oak pond, 1979, Six species occurred over the season (Figure A14). “Og‘gglgx_was observed first on April 6, 1979 followed by Ceriodaphnia reticulata (Jurine) on May 16, 1979. .9; reticulata is similar in appearance to §g_guadrangula, but is distinguished by the presence Of 6-8 toothlike pecten on its post-abdominal claw (Figures 8C and 80). ‘9; reticulata in Oak pond ranged in carapace lengths from 0.2 to 1.0 mm. Gravid females carried from 1 to 5 eggs in the brood pouch and one overwintering egg per ephippium. On May 9, 1979, in Oak pond, Daphnia rosea Sars was observed. This species was never observed in the other two ponds. Confusion exists over the taxonomic status of Daphnia rosea with respect to the species Daphnia longjspina (Brooks, 1957). According to Brooks (1957, and per. comm., 1979) these are two species which are morpho- logically similar. In North America, Brooks has found no single population conforming strictly to the description of Daphnia longj- spina. The species Daphnia rosea found in Oak pond was confirmed by Dr. Stanley Dodson at the University Of Wisconsin, Madison. Morphologically, Q; rosea was similar to Q; pulex, but was of smaller size (0.5 - 2.5 mm) and produced smaller clutch sizes (1-18 28 Figure 8. Daphnia rosea and Ceriodaphnia reticulata. A. gravid Q. rosea female B. Q, rosea postabdomen C. gravid Q. reticulata female D. g. reticulata postabdomen 30 parthenogenetic eggs). Other Characteristics included a head which was much deeper than long, a slender and long shell spine, and post- abdominal Claws with very fine pecten (Figures 8A and 88). Brooks (1957) described males and young females as having a toothed crest on the dorsal margin of the head. This character was not Observed on the Oak pond Q; ggggg, .anggggglis described as an inhabitant of Shallow waters, ponds, small lakes, swamps, and lagoons, and often in association with Q; pglgx, and although Brooks ((1957) reports the distribution of Q; [gggg is restricted to the western states and Canada, Dr. Stanely Dodson and others have found the species in Wisconsin, Michigan and Indiana (Dodson, 1980). In Oak pond, IDL.§g§gg_reached very high numbers, up to approximately 9000 per 100 liters and co-existed with §g_reticulata (Figure A14). On June 6, 1979, Chydorus sphaericus was found in Oak pond. On June 19 Simocephalus vetulus and Scapholeberis kingii were col- lected (Figure A14). Cg sphaericus, S; vetulus, and S; kingii were present until Oak pond dried up. During 1980, all the above species, except for E; sphaericus, were collected in the ten weeks I sampled Oak pond (Figure A15). THE OCCURRENCE OF OTHER INVERTEBRATES Although no quantitative measurements were taken, other inverte- brates found in the aquatic samples in the 1979 and 1980 season were noted. In April 1979 and 1980, Toumey, Oak and Upton pond samples included copepods, ostracods, fairy shrimp, isopods, gastropods, turbellarians, aquatic Oligochaetes, and the dipteran larvae Chaoborus gg: and Culex §g: During the same month Upton pond and Oak pond 31 also yielded water mites, fingernail clams, and trichopteran larvae. During the month of May 1979 and 1980 clam shrimp appeared in all three ponds, as well as odonata larvae. At this time, the fairy shrimp disappeared. In June, the clam shrimp disappeared and the majority of invertebrates collected were insect larvae. The dipteran larva Chaoborus gp, and the odonata larvae are predators of cladocerans. Chaoborus §p, was found in all three ponds and is known to nocturnally feed on small sized cladocerans, as do the odonata (Dodson, 1974). Invertebrates that might have had an indirect effect upon population numbers Of cladocerans were filter feeders that could compete for the available food resource. These included the fairy shrimp, clam shrimp, copepods and ostracods. THE EFFECTS OF TEMPERATURE ON CLADOCERAN POPULATION DYNAMICS Daphnia pulex is Often described as a spring or cold water cla- doceran and Ceriodaphnia spp., Simocephalus vetulus, Chydorus sphaeri- .gg§ and Scapholeberis kingii are described as summer or warm water organisms. In this study, 2; gglgx_was always the first species to occur in the spring in Toumey, Oak and Upton ponds. Its population numbers declined as other species began to appear. The relationships between the seasonal succession of Q; pglgg followed by cladocerans like Ceriodaphnia Egg. has been studied in other ponds (Lynch, 1978). William Neill (1975) suggested that Ceriodaphnia spp. can outcompete juvenile qugglgx for the limited particulate resources available thereby causing the demise of the D; gglgg population. In the spring of 1979 and 1980, observations were made on the suc- cession of Q; gulex followed by Ceriodaphnia spp. Often, Q; pulex 32 populations were declining before Ceriodaphnia spp. occurred and in several cases nearly 60% of adult Daphnia pulex females were forming ephippia several weeks before Ceriodaphnia spp. were collected. In Upton pond, 1979, no Ceriodaphnia spp. were found, yet the population rise and fall of Q; gglgx closely followed that of the ponds where both Species occurred. In 1980, Upton pond had both 0; gglgx and Ceriodaphnia spp. and their successional occurrence followed the same pattern previously described. Possibly no competition occurred between _D_._ pu_lgx_ and Ceriodaphnia gap. but rather the D_. m responded to other environmental factors. Dissolved oxygen, pH, and amount of suspended particulates were not correlated with any species specific abundance. Water temperature did seem to be related to zooplankton abundance. In all three ponds in 1979, D; gglgx_population decline and ephippia production consist- ently occurred when maximum temperatures reached 20-23°C (Figure 9). In Toumey and Oak ponds there was a mid-season decline in water tempera- ture in 1979. Associated with this temperature decline was a second peak in Q; gglg§_population Size (Figure 9). There is much evidence that Q; pglgx is a cold-water adapted organism. Feeding efficiency curves for D; gglgx predict that as water temperature increases above 20°C, fitness and optimal body size rapidly decline (Lynch, 1977). Hall (1964) reported that in Base Line Lake, 0; gglgx reached peak abundance in surface waters in spring (15-20°C) and then retreated to the thermocline as sunmer epilimnetic temperatures rose to 25°C. Similarly, Bell and Ward (1970) noted that in West Blue Lake, Manitoba, 0; gglgx remained in the cool deeper waters as summer epilimnetic temperatures rose to 22°C. 33 2000 - 0 . ’40 - Toumey Pond - 1500 «30 c?‘ . l 1000 ./-------~.’-"‘ - 20 o“‘\ g '3 500 103 3 \ g 1*. ‘ '5' , c 8 8 ... 400 F 30$ 5;; p Upton Pond 4 g g, - 'V°‘ 0 - 20 .1 a \CO d a 200 - - g g I- ‘ 10"?) '5 d .3 _- - P 0 a - 3 0 2000 r .1 40 A $4 é . 0 Oak Pond . $3, 1500 - , ,x - 30 V g ’I \‘ P.\,"~.‘/‘_C? D C A C 1000 . .X / ‘.‘ . . 20 P». “I, \\ ’1’ 1 I \ I 500 l— ": «I 10 I I .v m I v I I I r r I I I April May June July Sampling periods Key: Daphnia pulex Ceriodaphnia m.“ - - -- - -- - Date of first ephippia production in Daphnia pulex signified by: 0 Figure 9. Weekly maximum temperatures and density estimates of Daphnia pulex and Cerio- daphnia §pp, in Oak, Toumey. and Upton Ponds. 1979. 34 In environments where high summer temperatures cannot be avoided (as in the shallow temporary ponds of this study). the fitness curves for Q; pulex predict that optimal body size will be small and fitness low. Fitness curves for Ceriodaphnia spp. predict high fitness at these higher temperatures (Lynch, 1977). Water temperature may have an important effect on the population dynamics of cladoceran species. In the following discussion I have used data on D; gulex and Ceriodaphnia spp. populations from the three ponds studied in 1979 and 1980 in order to approach the possible relation of temperature to these species. Tables A3 and A4 list the weekly net gain or loss in numbers of Q; pulex and Ceriodaphnia spp. in all three ponds. Throughout the season there were fluctuations in population size in both species. Tables A5 and A6 present the weekly per capita gain or loss for each species. These figures were derived by dividing net gain or loss (from Tables A3, A4) by the mean number of individuals per week. The mean number of individuals per week was calculated by averaging the estimated population density of two consecutive sampling periods. The coefficient of population specific growth rate (r) can be calculated from two such measurements of population size, 1nN - 1nN _ t2 t1 r ‘ t2 - t1 (1) on the basis that _ r(t2-tl) since ‘gg = rN (3) 35 where Ntl and Nt2 are the population sizes at times t1 and t2. This "r" is a measure of the instantaneous rate of change of population size (per individual). It has the units 1/time and is expressed in numbers per unit time per individual. When births exceed deaths a population is increasing and "r" is positive; when deaths exceed births, "r" is negative and the population is decreasing. Figure 25 (from Pianka, 1978) demonstrates that Specific growth rate is a function Irfpopulation size because the population grows faster as N becomes larger. If "r" was constant the population would be increasing expo- nentially. Using equation (2), I calculated "r" values using time available for growth = one week, and population numbers of angglgx_a d 92319: daphnia spp. in all three ponds in 1979 and 1980 (Tables A7 and A8). I plotted all specific growth rates of Q; pulex and Ceriodaphnia spp. against mean water temperatures (maximum + minimum)/2 per week (Figure 11). Figure 11 illustrates that Qg_gglg§ populations in the three ponds generally increased (r > 0) when mean water temperatures were less than 15°C. Above this temperature 0; gglg§_population numbers decreased over time (r < O). The greater the value of r the faster a pOpUlation increases. Ceriodaphnia spp. had greater population increases (r > O) at mean water temperatures above 15°C. Large fluctua- tions are observed in the plot of D; pulex and Ceriodaphnia spp. population size versus time (FigUre 9). When specific growth rates (r) of Ceriodaphnia spp. and Qg_pglgx are plotted against mean tempera- tures (Figure 11) straight line relationships emerge. The line that fits the data for Qg_pglgx is described by y = -O.46x + 6.3 . The line fitted to Ceriodaphnia spp. data is described by y = 0.57x - 7.9 . Population size, N 36 All: dt rN (r = constant) 1 t1 t t. Time Figure 10. Exponential population growth (from Pianka, 1978) 37 SPECIFIC GROWTH RRTE PER WEEK (D " ‘ Lo_l fl ¢q . m“ l " CERIODHPHNIR 3?. N- o _ T— . n .. r I u d I\\ \\ “I,“ ‘ m \\ \ “ \ s'r-i * n LID T T T T I T T T T I T T T T I T T T T T T r T T I O s 10 15 20 25 MEHN TEMPERRTURE PER WEEK I C) Figure 11. Relationship between weekly mean water temperatures and specific growth rates of Daphnia pulex and Ceriodaphnia gpp. 38 This would indicate that some of the seasonal population fluctuation can be explained by Changes in water temperature. At even higher mean temperatures of 21-25°C, Ceriodaphnia spp. growth rates started to decrease (Tables A7 and A8). I did not plot this on Figure 11 because these high temperatures coincided with the time the ponds were drying up, making it unclear whether the decrease in growth rate at that time was a function of temperature or very shallow water. In these small temporary ponds when mean temperature rises above 15°C (maximum temperature above 20°C), 0; gglgx may not be as efficient filter feeders as other warm water species because of their lower feeding rate (Burns and Rigler, 1967). Ceriodaphnia spp., Q; rosea, .§; vetulus, C; sphaericus and S; kingii have a competitive advantage because they are more efficient feeders in warmer water. Hutchinson (1967) states that given a constant supply of food some species which mature faster at higher temperature may have an enormous selective advantage over other species. This physiological species-specific factor may provide temporal segregation of cladoceran species in a temporary pond. Some warm water species coexisted in these three ponds. This may be possible because there was a minimum of direct competition for available food. Among the warm water forms, since 5; vetulus spends much of its time gleaning food particles off aquatic macrophytes, it may not have directly competed for the suspended particulates. C. sphaericus and S; kingii had low population numbers and were probably not serious competitors with the more abundant Ceriodaphnia spp. 39 Further, g; sphaericus and S; kingii take food particles at the lower end of the food size range for Dg_gglgx and Ceriodaphnia spp. and do not completely overlap in the available food items. Although Species of cladocerans can occur in ponds at any time, the contention here is that each species grows best at certain species- specific temperatures. Temperature is a density independent factor, that is, it can affect a population regardless of numbers of individ- uals present. Food concentration, predators and competitiors are very important factors determining which cladoceran species is present at a certain time. But species-specific temperature optima must also be considered and investigated as possible population regulating parameters. SPECULATIONS FOR FUTURE STUDY In any natural situation, all physical and biological factors are inter-related and the importance of each is difficult to distin- guish. Controlled experimental conditions where pH, food, and dissolved oxygen are at a fixed optimum level could help elucidate whether temperature is a controlling factor in species population growth. One experiment might involve raising monocultures of Daphnia pulex at temperatures above and below a 16-20°c range, monocultures of some known warm water species under different temperature regimes, and .leggl 5 and a warm water species together under these conditions. An important indicator of unfavorable conditions for cladocerans in these temporary ponds seems to be the production of overwintering ephippial eggs. This unique option provides these animals with the capacity to repopulate a pond after a dry, or frozen period of time. 40 The emergence of larvae from these eggs in spring may also be triggered, at least in part, by water temperature. Dg_gglgx eggs may be physio- logically capable of hatching at much colder water temperatures than Ceriodaphnia spp. Any one particular factor such as water temperature is not the sole controller of any animal population, but it remains important to single out each possible controller and determine its limits for a particular species. A combination of these factors with their species specific limits may provide a definition of "niche" for a species. My observations of these temporary pond cladocerans may not hold true for other bodies of water. The genetic plasticity of these organisms allows for natural selection to affect them in unique ways in various environments. They may have produced the adaptations of temporal separation which allows several species to make use of this temporary habitat without directly competing with one another. SUMMARY AND CONCLUSIONS (1) Three temporary ponds in Michigan were sampled weekly from April through August, 1979 and April through June, 1980. (2) This study was conducted to observe the natural seasonal succes- sion of cladocerans in the temporary ponds and to discern if pH, dissolved oxygen, suspended particulates, or water temperature had any relationship to that succession. (3) In 1979, five species (five genera) of Cladocera were collected in Toumey pond, two species (two genera) in Upton pond, and six species (five genera) in Oak pond. In 1980, four species (four genera) were collected in Toumey pond, three Species (three genera) in Upton pond, and five Species (four genera) in Oak pond. (4) Water pH remained within a range suitable to all cladoceran species observed in the three ponds. (5) Dissolved oxygen concentrations ranged from 1-12 mg Oz/L. Cla- doceran populations were much reduCed when 00 levels reached 1 mg/L. (6) Density of suspended particulates within cladoceran food size range was not correlated with any one cladoceran species' population density, species' mean length or clutch size in any pond. There was no correlation between total number of cladocerans and particulate density. (7) Water temperature at time of sampling and particulate density were correlated in two ponds. 41 42 (8) Particulate density and chlorophyll absorbance in water samples were not correlated in two ponds and in all combined pond data. (9) Changes in water temperature and seasonal occurrence of Daphnia gglg§_and Ceriodaphnia spp. were examined. Qg_gglg§_appeared in the ponds and increased its population density at mean water tempera- tures less than 15°C. Ceriodaphnia spp. appeared in the ponds and increased in numbers at mean water temperatures greater than 15°C. (10) Water temperature may serve as one of many factors influencing the population dynamics of cladocerans. LITERATURE CITED LITERATURE CITED Anderson, 8.6., J. Lumer and L.J. Zupancic, Jr. 1937. Growth and variability in Daphnia pulex. Biol. Bull. 73:444-463. Bell, R.K. and F.J. Ward. 1970. Incorporation of organic carbon by Daphnia pulex. Limnol. Oceanogr. 15:713-726. Bhattacharyya, G.K. and R.A. Johnson. 1977. Statistical concepts and methods. John Wiley and Sons. New York, N.Y. Birge, E.A. 1898. Plankton studies on Lake Mendota II. Crustacea of plankton from July, 1894 to December, 1896. Trans. Wis. Acad. 11:274-448. Brooks, J.L. 1957. The systematics of North American Da hnia. Memoirs of the Connecticut Academy of Arts and Sciences. Vol. XIII:1-179. Brooks, J.L. 1968. The effects of prey size selection by lake plank- tivores. Syst. Zool. 17:273-291. Brooks, J.L. 1979. Personal communication. March 22. Brooks, J.L. and S. Dodson. 1965. Predation, body Size and composi- tion of the plankton. Science 150:28-35. Brower, J.E. and J.H. Zar. 1977. Field and laboratory methods for general ecology. Wm C Brown. Dubuque, Iowa. Brown, L.A. 1929. The natural history of cladocerans in relation to temperature. II. Temperature coefficients for development. Am. Nat. 63:346-352. ‘ Burns, C.W. 1968. The relationship between body size of filter- feeding Cladocera and the maximum size of particles ingested. Limnol. Oceanogr. 13:675-678. Burns, C.W. and F.H. Rigler. 1967. Comparisons of filtering rates of Daphnia rosea in lake water and in suspensions of yeast. Limnol. Oceanogr. 12:492-502. Dodson, 5.1. 1974. Zooplankton competition and predation: An experi- mental test of the size-efficiency hypothesis. Ecology 55:605-613. 43 44 Edmondson, W.T. 1957. Trophic relations of the zooplankton. Trans. Amer. Microsc. Soc. 76(3):225-245. Edmondson, W.T. 1959. Freshwater Biology. Wiley and Sons, New York, N.Y. Fisher, Z. 1970. Some remarks about the food ration. Polski Archiwum Hydrobiolgii. 17(30):l77-182. Foerster, J.W., F.R. Trainor, and J.D. Buck. 1974. Thermal effects on the Connecticut River: Phycology and chemistry. J. Water Pollut. Contr. Fed. 46:2138-2152. Glicwicz, Z.M. 1969. Studies on the feeding of pelagic zooplankton in lakes with varying trophy. Ekol. Pol. Ser. A. 17:663-707. Green, W.R. 1919. Studies in the life cycle of Simocephalus vetulus. Biol. Bull. 37:49. Hall, D.J. 1964. An experimental approach to the dynamics of a natural population of Daphnia galeata mendotae. Ecology 45:94-112. Hutchinson, G.E. 1967. A treatise on limnology. Vol. 2. Wiley and Sons, New York, N.Y. Ingle, L., T. Wood, and A.M. Banta. 1937. A study of longevity, growth, reproduction and heart rate in Daphnia longispina as in- fluenced by the limitations in the quantity of fOOd. Jour. Exp. 2001. 76:325-352. Jorgensen, C.B. 1962. The food of filter feeding organisms. Rappt. ProceS-Verbaux Reunions, Conseil Perm. Intern. Exploration Mer. 153:99-107. Kenk, R. 1949. The animal life of temporary and permanent ponds in southern Michigan. Misc. PUbl. Museum of Zoology, University of Michigan. No. 71. Kring, R.L. and W.J. O'Brien. 1976a. Accommodation of Daphnia pulex to altered pH conditions as measured by feeding rate. Limnol. Oceanogr. 21:313-315. Kring, R.L. and W. John O'Brien. 1976b. Effect of varying oxygen concentrations on the filtering rate of Daphnia pulex. Ecol. 57: 808-814. Kryuchkova, N.M. and V.K. Rybak. 1976. Growth of Daphnia magna Straus on a medium enriched with dissolved organic matter. Hydrobio. J. 12 (2):48:52. Lampert, Winfried. 1974. A method for determining food selection by zooplankton. Limnol. and Oceanogr. 19:995-998. 45 Lind, Owen T. 1979. Handbook of common methods in limnology. C.V. Mosby Co. St. Louis, MO. Lynch, M. 1977. Fitness and optimal body size in zooplankton popula- tions. Ecology 58:763-774. Lynch, M. 1978. Complex interactions between natural coexploiters - Daphnia and Ceriodaphnia. Ecology 59(3):552-564. Neill, W.E. 1975. Experimental studies of microcrustacean competition, community composition, and efficiency of resource utilization. Ecol. 56:809-826. Parlyutin, A.P. 1976. Food value of detritus for certain freshwater Cladocera species. Hydrol. J. 12(4):7-12. Petersen, W. 1926. Seasonal succession of animals in a Chara cattail pond. Ecology. 7:371-377. Pianka, Eric R. 1978. Evolutionary Ecology. Second Edition. Harper and Row Pub. New York, N.Y. Prouty, C.E. 1980. Personal communication. Dept. of Geology, Michigan State University, East Lansing, MI. Rodina, A.G. 1947. Experimental study of the feeding habits of Daphnia magna (on zooplankton feeding habits). Author's abstract of dissertation. Zool. Inst., Akad. Nauk. SSSR, Leningrad. Ward, Elizabeth. 1939. A seasonal population study of pond entomo- straca in the Cincinnati region. Amer. Midl. Nat. :635-681. Weglenska, T. 1971. The influence of various concentrations of natural food on the development, fecundity and production of planktonic crustacean filtrators. Ekol. Pol. 19:427-473. APPENDIX 00-0w 00-0N 00-0N 000.0 000.0 000.0 0.0 0.0 0.m 0 0 0 0.0 0.0 0.0 00 :00 :0-00 00-0N 00-00 000.0 000.0 000.0 0.0 0.0 0.0 m 0 0 0.0 0.0 0.0 0 :50 00-00 00-00 00-00 000.0 000.0 000.0 0.0 0.N N.m m 0 0 0.0 0.0 0.0 00 an: 00-00 00-00 00-00 000.0 000.0 000.0 N.N 0.N 0.0 n 0 0 0.0 0.0 0.0 mm 00: 00-0N N0-NN 00-0N 000.0 000.0 000.0 0.0 0.0 0.0 m 0 0 0.0 0.0 0.0 00 has 0 -NN 0 -0N 0 INN 000.0 000.0 000.0 0.0 N.0 N.0 0 0 0 0.0 0.0 0.0 00 has 0 -00 0 -00 0 -00 N00.0 000.0 000.0 0.0 0.0 0.N 0 0 0 0.0 0.0 0.0 0 002 00-00 00-00 00-00 000.0 000.0 000.0 0.N 0.0 0.N 0 0 0 0.0 0.0 0.0 0N :00 0 -00 0 -N 0 -n0 000.0 000.0 000.0 0.0 0.0 0.0 0 00 0 0.0 m.0 N.0 00 :00 0 -0 0 -0 0.0 0.0 0.0 0 00 N0 0.0 0.0 0.0 00 000 0.0 0.0 0.0 0 00 0 0.0 0.0 0.0 0 :00 no nu .0 no nu 10 no an .0 n0 nu 70 no nu .m mum mum mummmmmmm cm 0 m om om o ua u a as as us .A .A .A .A .A 0. Aaaannopoasov AH\wav AH\080 :0 090m 0:0a-x020 30000 90 00:00:0000 hpdm:0o on 00300000509 00903 canvmaoponnoupomnm 00000009000 .0000 .00:00 000 0:0 .:0000 .005309 00 000390000800 00003 :Ha-xmz 0:0 .00:mnhomnm 000008000:00090000 .mmpmasowphmm .:0mzxo 00>000000 .00 300003 .0: 00009 46 47 00-00 000.0 N 0.0 00 0:0 00-00 000.0 0.0 0 0.0 0 0:0 00-mm 000.0 0.0 0 N 0.0 0.0 0 0:0 00-0m 00-00 000.0 000.0 0.0 0.0 0 m 0.0 0.0 00 000 00-00 00-00 000.0 000.0 0.0 0.00 0 m 0.0 0.0 00 000 00-00 00-00 00-00 000.0 000.0 000.0 0 0 0 0.0 0.0 0.0 0 000 00-00 00-00 00-00 000.0 000.0 000.0 0.0 0.0 0.0 0 0 0 0.0 0.0 0.0 00 :00 000 o 00-000000000 mm.“ 0 mm 000000000 u a u a as Ha. us .A .A .A .A .A 0. 000000o0o0nov 00\030 00\w:0 00 0000 0:05-x0zv 08000 P0 00:0n0omn< 0000:00 on 00000000809 00003 000P0Soponno00000m 00000000000- . A 0.090000394099909 Table A2. Weekly pH, dissolved oxygen, and max-min water temperature of Toumey, Upton. and Oak Ponds. 1980. Water temperature D0 (Max-min) Date pH (mg/L) ‘0 i: g 3’ a a": s: 5 3 is 5 3 .3 5 3 g o a. o n. o a. 54 :2 c: e. :><3 e« :> :2 Apr 13 7.0 7.2 6.6 8 11 8 12- 1 16- 6 18- u Apr 29 7.3 7.h 6.6 8 8 3 18- 6 15- 6 19- 8 May 6 7.4 7.4 6.7 8 6 6 19- 9 17-10 21-10 May 14 7.3 6.1 7.0 8 7 3 21- 8 18- 8 21- 9 May 21 6.0 6.0 6.1 5 6 3 16-11 18-11 19-12 Jun 17 6.0 6.0 6.5 6 a 3 18-13 21-16 21-16 Jun 19 7.0 6.0 6.1 6 4 3 18-10 20- 7 20- 7 49 . . . mH wz¢n m mac . . 0.0flH+ . . . 0 wz 0. 2 . \x ’ x) — /\ \ a . , ‘2 . .0 x H 1 , 0 0 \ , . o \ or K I \\\ a g I 0 0 . ’os \ 2’ - I. 1. . _ , . 2 . , . 0 2 . x 0 .. ' II — ’ ~ II. I . I . 4 . j l r 1 .2 0.3000 .00x _N n m .0 com 1 O J 0000 m by w 00m0 o a J B 000w d 9 J 0000 .m 0 I To 000m .00 J 3 600 500 c- 0 ca 300 200 100 Number of Cladocera per 100 liters 56 Particulates (95% C.I.) \\\ b Cladocera 0 April May June Sampling periods 12.0 10.0 8.0 6.0 4.0 2.0 Figure A2. Temporal changes in total number of Cladocera and particulate density in Upton pond. 1979. (Jaqtt/Bm) thsuap aqetnotqaed 57 Particulate density (mg/liter) .0000 .0:00 000 :0 0000:00 00003000000 0:0 000000000 00 0008:: 00000 :0 000:0:0 00000800 .00 000000 .0.0 0mm 0:0 0000:00 00000000000 lllllllll .l. dhmOOflMHU 0%mvm 0000000 0:000800 00:0 0:00 202 0000< 0 _ 0 0 _ 0 1 _ 0 W . _ fi 0 0 0 .71.. \ OQN T \’ s s7 0 I. 0.00H N \ . 0 l \ L n , . 0 J. m , s 0 / 0. N. 0.: 1 0‘ /t\ J OOON J 2 .. 0 o 0 .l _ l O 0 a _ _ _ 000m m 0 . fi .- B , . _ w. Cam .I - - — I. coo: a , _ . a 0 _ . . W 0.00 1 . i. _ .. .. 0000 d , _ _ a . _ J H— - u I 0.N0 .. _ . .. 0000 O a — 0 o u . T. 0;: 1 . 0 1 0000 n . x n (x s 0.00 I 0 .L 0000 58 3000 f r Daphnia pulex 2000 1000 1000 F - Cerioda hnia uadran m 600 0 0 (D .. f. ,4 200 . 0 <0 Z 1000 r 8. - Simocephalus vetulus 600 - ‘2. m D O 0 .4 c) (S . 0 100 b Sca holeberis kin ii ,8 . 5 o L- z 5 1000 F - Chydorus sphaericus 600 . 0 200 . r I u I v fi I r v I April May June July Aug Sampling periods Figure an“ Weekly density estimates of Cladocera species in Toumey Pond. 1979. 59 700C 5000 3000 1000 U] 3; 3000f E b Ceriodaphnia guadrangu_la o 2000- O g-v. :- 3 1000- a. b a u 8 '8 3000f . ,fl . Simocephalus vetulus 0 2000. m‘ o D 3 1ooat .0 E . :3 :z T 1000- Chydorus sphaericus 600. ZN)- U I I Aprii I May I Eune Sampling periods Figure A5. Weekly density estimates of Cladocera species in Toumey Pond, 1980. 60 8 1- 3 0 7. 1. 2 3 t y l y m I any ‘I . a u .. um mm 1 .a .d I, l‘ I, J I I. L 6i J. I44 II I I, ll- 6 2 . . AU 7. u u A 1 l, 1 1 LT .A . Mm Ill, um um I I L JV 1 l. “J“ l. I, I J' 1% .. L- I, fil I, I] l j IT L . p r p L r p p p p L 0 0 O 0 0 0 O 0 0 O O o 3 2 1. 3 2 1. 3 2 1. 3 2 1 anommawo ouam :« acmoumm OCOHHHHNNNN oo.m-o nu.~-fi om.~-m n~.~-H oo.~-w ms.~-« on.H-w m~.H-« oo.H-o nu.ou~m om.o-oo.o BONMBON‘AN OOHHHHNNNN Carapace length (mm) Figure A6. Size distribution of Da hnia pulex in Toumey Pond. 1979. 30 20 10 30 20 10 30 20 Percent in size category 10 30 20 10 61 April 12 May 13 I III .lln.nllL1 April 20 May 19 .11] II 4 ”1'1” April 28 May 26 . IL... .1llHI w May 6 ‘15 June 3 I'll llln L l-lll IIUI|I1urrT I Ilrlirrl onomo‘nomomo omonomomono WRONWNONWNO “BONWNON‘ANO ooHHHHNNNNM OOHHHHNNNNM llllItlltll Ullllllllln oq-nOv-uOv-nownOv-no oq-nou-no—nov-noq-no otnLNONUNNON'nm OWLNONVNb-ONWN OOOHHHHNNNN OOOHHHHNNNN Carapace length (mm) Figure A7. Size distribution of Daphnia pulex in Toumey Pond. 1980. 30 20 10 30 20 10 30 Percent in size category 20 10 Figure A8. 62 April 12 May 3 l llllll ll|.ll [IL April 20 May 9 l li1ll|l .ll 11. April 27 May 16 VIIII I‘Tl Irv! III—'[U onenevxomomo omomo‘nomomo Qfiqqfi§9§0§9 9§9§9§9¥0§9 ooHHfiHNNNNM ooHHHHNNNNM 11111111111 11111111111 ov-uov-nou-nov-noq-no o—no—noq-oxov-NJon OOOHHfiHNNNN OWNONWBONWN QOOHHHHNNNN Carapace length (mm) Size distribution of Daphnia pulex in Upton Pond. 1979. 63 20 - 10 - E . II II. I I H IL 0 3? 'g 30 p April 20 May 14 O 3 20 - ”-1 m . 43 j j 7 1' III; C Q 8 52 33 30 " April 29 0 May 21 20 - 1° L | l I I II; IL 1 I ll 1 n I I IIIII IWTI III1Irr111 OWOWRWOWOV‘O OWOWO‘AOWOWO “NON NONV‘b-O “NONWNONV‘NO ooHHq-IHNNNNM OOHHHHN NNM IIIIIIIIII IIIIIU'I'II OHOHQH‘OHWHW OH‘OQ-ROw-HOH‘Ov-flo OWNONWNONMN OmNON‘nNONmfi OOOfiv-IHHNNNN OOOfiHHfiNNNN Carapace length (mm) Figure A9. Size distribution of Daphnia pulex in Upton Pond. 1980. 64 F 15 30- fl April 12 May 9 20- 101- 4 ILLLL1 1 lllllL h? E, 30- ‘ April 20 May 16 So q, 20- .p (U 3 II II :1 1| 7 Ill .1 I ll 7'] m g: l~11. ‘” 30- April 2? AMay 26 .p 1: 3 20.. $1 01 ‘3‘ 10- I [ll In. LLLIl l I 30- May 3 May 31 20- 10— l I ll. l-ll ll 1 1! l llilli1l '11 Ilrll omomomomomo onomomomomo “seepeeeeee 9§9%S%9N9§9 ooq-1v-1v-11-1NNNNM OOHHHHNNNNM 11111111111 11111111111 ou-1\o«-1\ou-1\ov-1\o.-1\o ov-1\os-1\os-1\ov-1\OH\O °0§9§0§9Q0§ 99%?fi9fi9fi0fi OOOHHHHNNNN OOOHHHHNNNN Figure A10. Carapace length (mm) Size distribution of Daphnia pulex in Oak Pond, 1979. 30 20 10 30 20 10 30 Percent in size category 20 10 Figure A11 . 65 April 5 I ll 56 “# April 13 i April 29 . 1 ....1.1[ April 20 May 6 .ll . ”I 1.11 Till Iii! V lll'l—Ill <3Ufiown$vncavwngo c>wwavu3vnauwownc> “NON .BON {\O “NONWBONWBO F4 1 OOOHHHHNNNN 0 1 6 1 6.. 1 6 1 6 1 6 OWNONWNONWB OOOHHHHNNNN Carapace length (mm) Size distribution of Daphnia pulex in Oak Pond, 1980. 66 WEEK. Simocephalus vetulus 0,00 p U) . a 3 300 b "-1 .-1 F 8 200 1 H h b 8. 100 . m . L1 0) O 8 M F H o P ‘13 5* p “P 3 3 g P z: 2- 1 .- 1 Figure A12. I r T I T U ' U I April May June Sampling periods Weekly density estimates of Cladocera species in Upton Pond, 1979. 67 noo- 300. Dearth—1e. 211.121.: zoo 100 3000- ' Ceriodaphnia reticulata 2000. led). 70p Number of Cladocera per 100 liters 50.. Scapholeberis kingii 30. 10. April I 'May‘ I J'une Sampling periods T V Figure A13. Weekly density estimates of Cladocera species in Upton Pond. 1980. 68 2°00 ‘ Daphnia pulex 1000 ~ 2000 P Ceriodaphnia reticulata L 1000 - a _ 0 +11 01-. 210000 1' Daphnia rosea o 1- I". g 5000 '- w L a. 8 , § 400 F Simocephalus vetulus c — .fl (J 200 - H - O 3 .2 800 F Chydorus sphaericus ;§ - #00 - zoor . .. Scapholeberis kingii 100 - ‘ 'Mag, ' ' June in? Sampling periods 'April Figure A114. Weekly density estimates of Cladocera species in Oak Pond, 1979. 69 2000 . Daphnia pulex 1000 . 25000 F m ' Ceriodaphnia reticulata A 15000 - G) .p I: . o 5000 ,- o» H E 25000 a - Daphnia rosea A 15000 - 0 O o h '3 000 14 5 ’ c) c... 0 p 3 100 . Simocephalus vetulus .0 E .. g 50 ’ 50 E Scapholeberis kingii 25- T I I I 1 v I v I U *1 April May June Sampling periods Figure A13. Weekly density estimates of Cladocera species in Oak Pond. 1980.