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•
The macroinvertebrate community of vernal pools in southwestem Quebec
by
Bruce R. Doran
• Natural Resource Sciences (Entomology) McGill University, Montreal, Quebec
September 1999
A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfilment of the requirements ofthe degree of Master of Science
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Canadri -ü- • Abstract Temporary snowmelt pool ecosystems in southwestern Quebec were examined with special emphasis on identifying the macrofauna and determining their spatial distribution, as weIl as ascertaining temporal changes in community composition. 68 taxa were collected from ten snowmelt pools. Major taxa represented were Diptera, Coleoptera, Hemiptera, Trichoptera, Odonata, Ephemeroptera, Anostraca, Isopoda, Amphipoda, Gastropoda and Bivalvia; the insects dominated the communities and the Culicidae (Diptera) was the most abundant taxon collected. The fauna were unevenly distributed bath spatially and temporally amongst the pools. The occurrence of taxa was similar in pools in the same geographic location. The habitat characteristics of each pool, coupled with their proximity to a permanent waterbody and their accessibility ta organisms, perhaps influenced the distribution of the various taxa. A successional pattern was observed in which filter-feeders and detritivores appeared fust, followed by predators. After drought, a similar pattern was seen in pools that were replenished by summer rains, but taxon diversity was lower. In • addition, pools with longer hydroperiods harboured more taxa than shorter-lived pools.
• -111- • Résumé Une étude de dix mares alimentées par l'eau de fonte des neiges dans le sud-ouest du Québec a permis de déterminer la composition taxonomique, la distribution spatiale et la succession saisonnière de la macrofaune. On y a dénombré 68 taxons, dont les Diptera, Coleoptera, Hemiptera, Trichoptera, Odonata, Ephemeroptera, Anostraca, Isopoda, Amphipoda, Gastropoda and Bivalvia; les insects dominaient les communautés et les Culicidae (Diptera) ont été le plus abondants. Parmi les étangs, la faune s'est répartie inégalement dans le temps et l'espace. Généralement, en l'occurrence, les taxons étaient similaires dans les étangs de la même location géographique. La distribution des taxons a peut-être été influencée par les caractéristique de l'habitat de chaque étang, leur accessibilité envers les organismes et leur proximité à une masse d'eau permanente. On a observé une succession écologique d'organismes filteurs et détritivores apparaissant en premier, suivi par des prédateurs. Après la sécheresse des étangs saisonniers, la succession écologique est réapparue dans les étangs réapprovisionnés par les pluie d'été. Par contre la diversité des • communautés était moindre. En outre, les étangs avec plus longs hydropériodes hébergeaient plus de taxon que des étangs à courtes hydropériodes.
• -iv-
Suggested short dtle
Macroinvertebrate vernal pool communities
• -v-
Acknowledgments
l wish ta thank members of my supervisory committee, Dr. R.K. Stewart, Dr. T.A Wheeler and Dr. DJ. Lewis for their suggestions. 1especially wish to thank my supervisor, Dr. DJ. Lewis, for his guidance and availability; without bis help 1 doubt that tbis thesis would have ever been completed. 1 thank Dr. DJ. Larson (Dept. of Biology, Memorial University of Newfoundland) for identifying sorne of my Coleoptera specimens and also Mrs. Louise Clouùer (Coordinator of Zoological Collecùon, University of Montreal) who was extremely helpful in identifying my Chironomidae larvae. 1 thank Dr. R. Bider (St. Lawrence Valley Natural History Society, Ecomuseum) and Mr. J. Watson (Morgan Arboretum) for helping me locate sorne of my pools. l wish to thank. an my friends and my family for supporting me during the past two years. Their constant encouragement helped me persevere throughout hardships. Funding for tbis research was partly obtained through a scholarship from the Natural Sciences and Engineering Research Council (NSERC). -vi- • Table ofContents Abstra~t ü
Résumé ID
Suggested short title iv
Acknowledgments v
Table of Contents VI
List ofTable, Figures and Appendices ix
lntroducùon 1
Literature Review 2
Introduction 2
Types and classüication of temporary habitats 3 • Global studies on temporary habitats 4 Ephemeral ponds and pool~ ofCanada 6
Faunal diversity and community succession in temporary ponds and pools ... 7
Scope of previous studies on ternporary ponds and pools 10
Faunal collecùon methods Il
Materials and Methods 12
Choice and description of temporary vernal poo~ 12
Sampling period 12 • Sampling methods 13 -vü- • Macroinvertebrate identification ... 14 Results and Discussion 15
Community composition of temporary pools 15
Culicidae 15 Chaoboridae 16 Chironomidae 16 Dixidae, Syrphidae and Tipulidae 17 Coleoptera 17 Hemiptera 18 Trichoptera 18 Odonata 19 Ephemeroptera 19 Anostraca 20 Isopoda 20 Amphip0 da 20 Gastropoda 21 Bivalvia 21 • Abundance of taxa collected 21 Culicidae 22 Chaoboridae 24 Chironomidae ... 25 Dixidae, Syrphidae and Tipulidae ... 26 Coleoptera ... 26 Hemiptera 27 Trichoptera, Odonata and Ephemeroptera ... 27 Anostraca, Isopoda, Amphipoda, Gastropoda and Bivalvia ... 27
Temporal changes in community composition ... 28
Culicidae ... 29 Chaoboridae ... 33 Chironomidae 33 Dixidae, Syrphidae and Tipulidae ... 36 • -vüi-
Coleoptera • oytiscidae (a) Adults 37 (h) Larvae 37 Hydrophilidae (a) Adults 38 (h) Larvae 38 Hydraenidae (a) Adults 38 Hemiptera 40 Trichoptera 40 Odonata 40 Ephemeroptera 41 Anostraca 41 Isopoda and Arnphipoda 41 Gastropoda 42 Bivalvia 42
Total number of taxa per pool in relaùon to its hydroperiod 42
Summary of successional patterns observed in study pools 44
• Conclusions ... 47 References ... 115
• -ïx-
List ofTable, Figures and Appendices
• Table
Table 1: Total Nurnber of Specimens Collected per Taxon in Pools in Southwestern Quebec ... 50
Figures
Figure 1: Seasonality ofAedes provoeans in various pools (Southwestem Quebec): April-July 1998 ... 55
Figure 2: Seasonality ofAedes communis in various pools (Southwestem Quebec): April-July 1998 .. , 55
Figure 3: Seasonality ofAedes stimulans in various pools (Southwestem Quebec): April-July 1998 ... 56
Figure 4: Seasonality ofAedes inlrudens in various pools (Southwestem Quebec): April-July 1998 ... 56
Figure 5: Seasonality ofAedes punetor in various pools (Southwestem Quebec): April-July 1998 .,. 57
Figure 6: Seasonality ofAedes euedes in various pools (Southwestem Quebec): April-July 1998 ... 57
Figure 7: Seasonality ofAedes exerueians in various pools (Southwestern Quebec): April-July 1998 ... 58
Figure 8: Seasonality ofAedes diantaeus in various pools (Southwestern Quebec): April-July 1998 ... 58
Figure 9: Seasonality ofAedes canadensis in various pools (Southwestern Quebec): April-July 1998 ... 59
Figure 10: Seasonality ofAedes cinereus in various pools (Southwestem Quebec): April-July 1998 ... 59
Figure Il: Seasonality ofAedes vexans in various pools (Southwestern Quebec): April-July 1998 ... 60 -x-
Figure 12: Seasonality of Culex pipiens in various pools • (Southwestem Quebec): April-July 1998 ... 60 Figure 13: Seasonality ofCulex restuans in various pools (Southwestem Quebec): April-July 1998 ... 61
Figure 14: Seasonality of Culex territans in various pools (Southwestem Quebec): April-July 1998 ... 61
Figure 15: Seasonality of AnopheLes quadrimaculatus m various pools (Southwestem Quebec): April-July 1998 ... 62
Figure 16: Seasonality ofMo chlonyx spp. in various pools (Southwestem Quebec): April-July 1998 ... 62
Figure 17: Seasonality of Chaoborus americanus in various pools (Southwestern Quebec): April-July 1998 ... 63
Figure 18: Seasonality of Chaoborus flavicans in various pools (Southwestern Quebec): April-July 1998 ... 63
Figure 19: Seasonality of Limnophyes spp. in various pools (Southwestern Quebec): April-July 1998 ... 64
Figure 20: Seasonality of Doithrix spp. in various pools (Southwestem Quebec): April-July 1998 ... 64
Figure 21: Seasonality ofHydrobaenus spp. in various pools (Southwestem Quebec): April-July 1998 ... 65
Figure 22: Seasonality of Chironomus spp. in various pools (Southwestem Quebec): April-July 1998 ... 65
Figure 23: Seasonality of Phaenopsectra spp. in various pools (Southwestem Quebec): April-Joly 1998 ... 65
Figure 24: Seasonality of Corynoneura spp. in various pools (Southwestern Quebec): April-July 1998 ... 66
Figure 25: Seasonality of Eukiefferiella spp. in various pools (Southwestem Quebec): April-Joly 1998 ... 66 • -xi-
Figure 26: Seasonality of Pseetrotanypus spp. in various pools • (Southwestem Quebec): April-July 1998 ... 66 Figure 27: Seasonality of Larsia spp. in various pools (Southwestem Quebec): April-July 1998 .. , 67
Figure 28: Seasonality ofHamisehia spp. in various pools (Southwestem Quebec): April-July 1998 ... 67
Figure 29: Seasonality of Polypedilum spp. in various pools (Southwestern Quebec): April-July 1998 .. , 67
Figure 30: Seasonality of Pseudoehironomus spp. in various pools (Southwestem Quehec): April-Ju1y 1998 ... 68
Figure 31: Seas0 nality ofSmittia spp. in various pools (Southwestern Quebec): April-July 1998 ... 68
Figure 32: Seasonality ofZavrelimyia spp. in various pools (Southwestern Quebec): April-Ju1y 1998 ... 68
Figure 33: Seasonality of Eristalis spp. in various pools • (Southwestern Quebec): April-Ju1y 1998 ... 69 Figure 34: Seasonality ofHydroporus spp. (Adults) in various pools (Southwestern Quebec): April-July 1998 ... 69
Figure 35: Seasonality of Laccophilius spp. (Adults) in various pools (Southwestem Quebec): April-July 1998 ... 70
Figure 36: Seasonality ofAgabus spp. (Larvae) in various pools (Southwestem Quebec): April-July 1998 ... 70
Figure 37: Seasonality of Colymbetes spp. (Larvae) in various pools (Southwestem Quebec): April-July 1998 ... 70
Figure 38: Seasonality ofDytiseus spp. (Larvae) in various pools (Southwestem Quebec): Aprîl-July 1998 ... 71
Figure 39: Seasonality ofAcilius spp. (Larvae) in various pools (Southwestem Quebec): April-July 1998 _._ 71 • -xü-
Figure 40: Seasonality ofHygrotus spp. (Larvae) in various pools (Southwestem Quebec): April-July 1998 ... 72
Figure 41: Seasonality ofHydaticus sp. (Larva) in various pools (Southwestem Quebec): April-July 1998 ... 72
Figure 42: Seasonality ofAnacaena limbata (Adults) in various pools (Southwestem Quebec): April-July 1998 ... 73
Figure 43: Seasonality ofHelophorus spp. (Adults) in various pools (Southwestem Quebec): April-July 1998 ... 73
Figure 44: Seasonality of Berosus striatus (Adults) in various pools (Southwestem Quebec): April-July 1998 ... 74
Figure 45: Seasonality of Hydrobius spp. (Adults) in various pools (Southwestem Quebec): April-July 1998 ... 74
Figure 46: Seasonality of Hydrochara spp. (Adults) in various pools (Southwestem Quebec): April-July 1998 .,. 74
Figure 47: Seasonality of Cymbiodyta spp. (Adults) in various pools (Southwestem Quebec): April-July 1998 --. 75
Figure 48: Seasonality of Helophorus spp. (Larvae) in various pools (Southwestem Quebec): April-July 1998 ... 75
Figure 49: Seasonality ofHydrobius spp. (Larvae) in various pools (Southwestern Quebec): April-July 1998 ... 75
Figure 50: Seasonality of Hydrochara spp. (Larvae) in various pools (Southwestem Quebec): April-July 1998 ... 76
Figure 51: Seasonality ofHydraena spp. (Adults) in various pools (Southwestem Quebec): April-July 1998 ... 76
Figure 52: Seasonality of Dasycorixa spp. in various pools (Southwestem Quebec): April-July 1998 ... 76
Figure 53: Seasonality of Callicorixa sp. in various pools (Southwestem Quebec): April-July 1998 ... 77 -xiii-
Figure 54: Seasonality ofTrichocorixa spp. in various pools • (Southwestem Quebec): April-July 1998 ... 77 Figure 55: Seasonality ofLimnephilus spp. in various pools (Southwestem Quebec): April-July 1998 ... 77
Figure 56: Seasonality ofIronoquia spp. in various pools (Southwestern Quebec): April-July 1998 ... 78
Figure 57: Seasonality of Eubranchipus bundyi in various pools (Southwestem Quebec): April-July 1998 ... 78
Figure 58: Seasonality of Caecidota forbesi in various pools (Southwestem Quebec): April-July 1998 ... 78
Figure 59: Seas0 nality ofAplexa elongata in various pools (Southwestem Quebec): April-July 1998 ... 79
Figure 60: Seasonality of Gyraulus spp. in various pools (Southwestem Quebec): April-July 1998 ... 79
Figure 61: Seasonality ofStagnicola spp. in various pools • (Southwestem Quebec): April-July 1998 '" 79 Figure 62: Seasonality of Lymnaea sp. in various pools (Southwestem Quebec): April-July 1998 ... 80
Figure 63: Seasonality ofSphaerium occidentale in various pools (Southwestem Quebec): April-July 1998 ... 80
Figure 64: Percentage Abundance ofAedes species Morgan Arboretum Pool #2 (SW Quebec) ... 81
Figure 65: Percentage Abundance ofAedes species Morgan Arboretum Pool #3 (SW Quebec) ... 82
Figure 66: Percentage Abundance ofAedes species Morgan Arboretum Pool #4 (SW Quebec) ... 83
Figure 67: Percentage Abundance ofAedes species Morgan Arboretum Pool #5 (SW Quebec) ... 84 • •xiv-
Figure 68: Percentage Abundance ofAedes species Senneville Pool #1 (SW Quebec) ... 85
Figure 69: Percentage Abundance ofAedes species Senneville Pool #2 (SW Quebec) ... 86
Figure 70: Percentage Abundance ofAedes species Senneville Pool #3 (SW Quebec) ... 87
Figure 71: Percentage Abundance ofAedes species Senneville Pool #4 (SW Quebec) ... 88
Figure 72: Percentage Abundance of Culex species Morgan Arboretum Pool #5 (SW Quebec) ... 89
Figure 73: Percentage Abundance of Culex species Senneville Pool #3 (SW Quebec) ... 90
Figure 74: Percentage Abundance ofChironomidae Morgan Arboretum Pool #2 (SW Quebec) .., 91
Figure 75: Percentage Abundance ofChironomidae Morgan Arboretum Pool #3 (SW Quebec) ... 92
Figure 76: Percentage Abundance ofChironomidae Morgan Arboretum Pool #4 (SW Quebec) ... 93
Figure 77: Percentage Abundance ofChironomidae Morgan Arboretum Pool #5 (SW Quebec) ... 94
Figure 78: Percentage Abundance ofChironomidae Senneville Pool #1 (SW Quebec) ... 95
Figure 79: Percentage Abundance of Chironomidae Senneville Pool #2 (SW Quebec) ... 96
Figure 80: Percentage Abundance ofChironomidae Senneville Pool #3 (SW Quebec) ... 97
Figure 81: Percentage Abundance ofChironomidae Senneville Pool #4 (SW Quebec) ... 98 • -xv-
Figure 82: Total Number ofTaxa Collected Per Pool in Relation ta its Hydroperiod ... 99
Figure 83: Taxa Collected in Wildlife Area Pool #1 (Southwestern Quebec): April- July 1998 ... 100
Figure 84: Taxa Collected in Wildlife Area Pool #2 (Southwestern Quebec): April- July 1998 ... 100
Figure 85: Taxa Collected in Morgan Arboretum Pool #2 (Southwestern Quebec): April- July 1998 ... 101
Figure 86: Taxa Collected in Morgan Arboretum Pool #3 (Southwestem Quebec): April- July 1998 ... 101
Figure 87: Taxa Collected in Morgan Arboretum Pool #4 (Southwestern Quebec): April - July 1998 ... 102
Figure 88: Taxa Collected in Morgan Arboretum Pool #5 (Southwestem Quebec): April- July 1998 ... 102
Figure 89: Taxa Collected in Senneville Pool #1 • (Southwestern Quebec): April- July 1998 ... 103 Figure 90: Taxa Collected in Senneville Pool #2 (Southwestern Quebec): April- July 1998 ... 104
Figure 91: Taxa Collected in Senneville Pool #3 (Southwestern Quebec): April- July 1998 ... 105
Figure 92: Taxa Collected in Senneville Pool #4 (Southwestern Quebec): April- July 1998 ... 106
Appendices
Appendix 1: Location ofPools ... 107
Appendix 2: Description ofTemporary Snowmelt Pools in Southwestem Quebec, 1998 ... 108
Appendix 3: Morphometric and Water Temperature Data ofVemal Pools in Southwestern Quebec, 1998 ... 109 -XVÏ-
Appendix 4: Average Air Temperatures and Total Precipitation • for April-July) 1997-1998 ... 114
•
• • Introduction Most studies on temporary habitats have been conducted in semi-arid and arid regions around the world with very little emphasis on temperate zones. Also many ofthese projects have restricted their scope to ooly a few organisms within each habitat, while overlooking the rest of the community. With trus in mind, temporary snowmelt pool ecosystems were ~xamined since they have generally been overlooked and little are known about them. Except for northern regions, this is especially true in Quebec where work on these habitats has been lad~ing. Basic information, such as species diversity, is still unknown and a comprehensive study ofthese systems is greatly needed. This project focused on determining the community composition in temporary snowmelt pools in southem Quebee, with special emphasis on identifying the macrofauna. This study was conducted during the entire hydroperiod ofeach pool so as ta demonstrate temporal changes in community composition. • The objectives of this study were: 1) To determine the community and species composition of temporary snowmelt pools in southwestem Quebee.
2) To demonstrate the spatial and temporal distribution of taxa.
3) To demonstrate differences in community composition ofeach pool in relation to its hydroperiod.
• 2 • Literature Review Introduction
Lotie and lentic freshwater systems have been extensively studied and a great deal is known about their biotic communities. However, much more work needs ta be done, and thus far mase studies have concentrated on permanent waterbodies. Temporary orephemeral fresh waters, which are defmed as bodies of water that experience a recurrent dry phase of varying length and predictability (Williams, 1996), have not been investigated ta any great extent. Literature of temporary waters is largely scattered (King et al., 1996) and only in the past 10-15 years have these systems started to get attention, with most work being done in
the last seven years. Il seems surprising that temporary habitats have been overlaoked for 50 iong. There are severa! reasons which may explain the lack of studies on these systems. Ephemeral waterbodies tend ta he sma1l and occur in reroote areas (McLachlan, 1981), and therefore are very easy to miss. Moreover, they disappear at cenain times of the year making • them even more difficult to locale. There is also a generallack of interest in studying these systems, since they are small and viewed as "unimponant" habitats compared to larger more permanent systems. Temporary freshwaters have traditionally been considered more abundant in arid and semi-arid regions... around the world (Williams. 1996). Since these drier areas are typically found in developing countries, such as many of the African nations, it can he speculated that the scarcity ofstudies could be related to the availability ofresearch funds. Temporary waterbodies have gained attenùonover the past few years. More and more scientists are becoming aware of the importance of these habitats to many organisms which utilize them for various purposes. They have realized that ephemeral waters could potentially be an important water source in many arid and semi-arid regions due to the paucity of permanent waters (Williams, 1985). These temporary habitats would therefore he of great ecological significance ta organisms that need waterbodies for reproduction and development. Another benefit of studying these temporary waters is that ecological • investigations can be easily done because of the habitat's small size (McLaclùan, 1981). 3
They can be used for population dynamics studies, investigating predator-prey and • competitive interactions, as weIl as testing successional and island biogeography theories (Ebert & Balko, 1981; Williams, 1996; Meintjes, 1996). Ephemeral habitats can also afford important advantages for examining the relationship between habitat duration and community structure (Schneider & Frost, 1996). Habitat duration can he clearly detined (with the drying event being the endpoint) and the entire assemblage of organisms are under similar conditions since individual habitats are nearly homogeneous. In addition, temporary habitats in the same region are often identical and thus provide one of the tew situations in which replication is commonplace and hence are ideal subjects for ecological studies (Kitching, 1987). Despite their small size, temporary systems have been shown to provide habitats for important assemblages of rare and endangered species (Collinson et al., (995). Since these habitats are usually small and shallow, they tend to he vulnerable ta damage by human activities, such as pollution l'rom precipitation or surface runoffs or filling during agricultural operations and urbanization. Therefore, a better understanding of these temporary habitats is needed to determine their importance in the survival of certain biota. • FinaUy, ephemeral habitats can he utilized to demonstrate differences or similarities in community composition, growth rates and life cycles of various biota to those of permanent waters (Williams, 1987). They can also aid us in understanding the evolutionary dynamics that have influenced the adaptations of various species exploiting these temporary habitats (King et al., 1996).
Types and classification of temporary habitats
The term temporary waterbody encompasses a wide group ofhabitats that at certain limes are without water. Many attempts have been made to categorize these temporary systems based on size and depth (Williams, 1987), but the main difficulty in using such criteria is thd.l these will undoubtedly change as a result ofdrying and the classitication of each habitat will alter over time. Williams (1985) has suggested utilizing three main • components of temporary habitats in arder ta classify them: (i) salinity (saline versus 4
nonsaline), (ü) the extent to which the waters occupY discrete basins or are associated with • rivers and (m) the degree of predictability that they contain water. Because ofthe difficulties in working with erratic habitats, many scientists have decided ta focus their attention on more periodic systems. Through the combination ofthe above components we obtain three major predictable types of temporary waterbodies which can he subdivided into different categories. Predictable saline habitats include temporary desert and rock pools (Blaustein et al., 1996); predictable lotic habitats are usually found in the fonn of intermittent streams and rivers (Abell, 1981; Delucchi, 1998; Closs & Lake, 1994: Williams, 1996); and predictable discrete water filled basins include rock rain-pools (Mc Lachlan, 1983: Zamora-Munoz & Svensson, 1996), temporary desert pools (Blaustein et al., 1996), t~mporary ponds and pools (Mozley, 1932; Thiery, 1991: Renshaw et aL.. 1995: : King et al.. 1996) and even phytotelmata (Kitching, 1987: Bradshaw & Holzapfel. 1988: Juliano & Stoffregen, 1994). It should be mentioned that rnany of the names given ta these different habitats can be further classified depending on the region in which they are found and on the period ofdrought and tilling that these systems experience. For example, the term temporary • pond refers ta a wide range ofbasins, such as vernal pools and desert ephemeral pans. VenlaI pools are replenished with water in the spring by snowmelt and dry out by autumn (King et al., 1996), whereas desert ephemeral pans obtain water in the winter and dry out by early summer (Blaustein et al.. 1996). Therefore, terms given ta each type of ephemeral habitat must take into account its geographic location and climatalogy (Williams, 1996).
Global studies on ternporary habitats
Even though phytotelmata or "pitcher" plants have been studied with sorne interest (Kitching, 1987: Bradshaw & Holzapfel, 1988; Juliano & Stoffregen, 1994), most studies on temporary habitats have focused their attention on temporary ponds or pools and intermittent streams. Moreover, most studies have heen conducted in semi-arid and arid regions around the world where these temporary systems are found in abundance (Williams, 1985). Most • intemùttent stream studies have been concentrated in Australia (Williams, 1985; Boulton & 5
SUler, 1986~ Closs & Lake, 1994) and in the state ofCalifornia (Abell, 1981). Studies done • on temporary ponds and pools have been conducted in warmer regions around the world like South and Central Africa (McLachlan, 1981; McLachlan, 1983; McLachlan, 1988; ~v1cLachlan & Yonow, 1989; McLachlan, 1993~ Meintjes, 1996), Morocco (Thiery, 1991), Israel (Blaustein & Margalit, 1994; Blaustein et al., 1995; Blaustein etal., 1996), South India (Miller, 1992), Australia (Hodgkin & Watson, 1958; Williams, 1985) and in the southern United States (Cole, 1966), including South and North Caralina (Taylor et al., 1988; Wilbur, 1987: tvlahoney et al., 1990) and California (Dehaney & LaVigne, 198 i: Sands, 1981; King etai.. 1996). Although temporary habitats have been associated primarily with hot climates, they can also be found in temperate regions such as North America and Europe (Williams, 1987). It has aIse been speculated that temporary habitats in these regians may he as numeraus as thase found in semi-arid and arid zones, but more important1y they tend ta be more predictable and more identical ta one anather (Williams. 1987). Hence. ephemeral habitats in temperate zones are more interesting subjects ofstudy. Intermittent streams of temperate • regions have received attention only in North America in areas like northem V.S. New Eng1and states (Delucchi, 1998; Delucchi, 1989), Ohio (Stehr & Bransan, 1938) and the Canadian Province ofOntario (Williams, 1977; Williams and Hynes, 1977: Williams, 1987). On the other hand, ephemeral ponds and pools in temperate regions have been studied in both North America and Europe. Studies have been conducted in England (Fryer, 1985; Collinson et al., 1995; Renshaw et al., 1995), Scotland (Jeffries, 1994), Sweden (Nilsson & Svensson, 1995: Nilsson & Soderberg, 1996; Zamora-Munoz & Svensson, 1996), nonhern U.S. states like Minnesota (Hombach et al., 1991), Ohio (Hambach et aL., 1980), Michigan (DeWitt, 1955: Thomas, 1963; Jokinen, 1978; Engle, 1985), Washington (Girdner & Larson, 1995) and New England states (Cole & Fisher, 1979) and western Canadian provinces such as Manitoba (Mozley, 1932; Daborn & Clifford, 1974; LaBerge & Hann, 1990), Alberta (Donald, 1983) and British Columbia (Melay, 1978). It is interesting to note that very few studies on temporary ponds and pools have been performed in eastemCanada. Most projects • in eastem Canada invalving temporary habitats have been done by 0.0. Williams and ms 6
group on lotic systems and by a Université du Québec à Trois-Rivière (UQTR) research • group on mosquito pools in northem Quebec (Mailhot & Mairet 1978~ Maire et al.. L978; rvlaire & Aubin, 1979; Maire & Aubin, 1980; Tessier et al., L981~ Maire, 1982). Few studies on temporary ponds and pools have been conducted in Ontario (Paterson & Fernando. 1969~ Harper & Hynes, 1970; McKee & Madde, L981) and southem Quehec (Williams, 1987; Alaire & LeClair, L988).
Ephemeral ponds and pools ofCanada
Ephemeral ponds and pools in Canada are known as vernal habitats. Vernal pools and ponds are temporary basins which fùl with water l'rom melting snow and spring rains, retain surface water until midsummer and are dry throughout late summer, autumn and winter (MozleYt 1932; \Vard, 1992). These depressions can he round anywhere including agricultural lands, woodlots, abandoned mines and roadsides. It has been surmised that perhaps one of the reasons why these pools and ponds have been studied mainly in western • Ci.mada could be due to the more stable environment found in this area (Dabom, 1976). The main problem with temporary ponds in eastem Canada, is that although they usually till up after spring thaw, rnild winters or Low precipitation could potentially leave them dry. [n contrast, the amount of precipitation in western regions is more constant year after year and consequently basins tend to fill every season (Dabom, 1976). This lack of predictability of rainfall in eastem provinces has probably deterred scientists from studying such habitats. Another reason for the lack of studies could he due ta the geography of the area. Prairie provinces tend ta be flat and with little tree caver, and ponds could he Located and accessed easily. Eastern regions tend to he a bit more rugged, with much tree cover. Vernal ponds and pools tend to he round more often in woodlots, therefore making them more difficult to study (Williams, 1987). Nevenheless, these habitats should not he neglected since they can he numerically abundant in certain regions (especially in the more nonhem latitudes) and because of their simple physical nature, high conformitYis common among pools (Nilsson • & Svensson, 1995). Because of their characteristics, eastern Canadian vernal pools lend 7 • themselves to a great variety ofecologica! studies. Faunal diversity and community succession in temporary ponds and pools
These periodic habitats have recurrent dry phases of variable length, that can last anywhere from a few weeks to severa! months (Williams, L987). Many factors determine the lcngths of the dry and wet phases ofeach type of habitat and these will be closely related to their geographic location. The arnount of moisture that enters the system and the rate of evaporation and infùtration are the most important factors that will determine the length of each phase (Williams, L987). From a biotic stand-point, the length of the dry season is perhaps the most inHuential factor that will affect organisms living in these habitats (Wiggins et al., L980: Williams, 1987). The drying out of the basin is the harshest type of factor or disruption that will determine which organisms can survive. As Wiggins et al. (1980) noted. pools that were dry for longer periods aftime had fewer species in common with permanent systems, than thase that were dry for shorter episades of time. Therefore, the length of the • dry period will determine the community structure and species diversity found within each temporary habitat (Wiggins et al.. 1980). Not ail freshwater aquatic organisms found in permanent habitats are capable of living in temporary systems. In fact, ooly those organisms capable of surviving the dry period can pursue their life in an ever changing system. Adaptations ta resist desiccation either in the fonn of resistant eggs and larvae or overwintering in an area other than the temporary basin (Williams, 1987: Maitland 1990; Schneider & Frost, 1996), are all strategies employed by temporary water inhabitants. No matter what strategies used, all temporary water inhabitants have stages in their life cycle which are resistant to desiccation (Bayly & Williams, 1973). One taxon not found in ephemeral habitats is the Neuroptera since it has not developed the capability ofdealing with drought (Williams, 1996). On the other hand, certain organisms an:: found exclusively in temporary habitats and are even nicknamed as IItemporary habitat taxa tl (Meintjes, 1996); these organisms include the branchiopods Anostraca (fairy • shrimp) and Notostraca (tadpole shrimp) which are cosmopolitan. Many other groups of 8
organisms are common in ephemeral habitats but not necessarily restricted ta them. • Temporary pands and pools usually suppon a wide variety of insect, cladoceran and even gastropod and bivalve taxa. Ephemeral pools have especially diverse beetle, bug and midge cornmunities (Ward, 1992: Batzer & Wisseger, 1996). Examples of insects faund within temporary ponds and pools include nektonic bugs such as notonectids. corixids and belostomatids, beetles like dysticids and hydrophilids. certain tichopteran graups, the dipteran tipulids. culicids, ceratopoganoids, ephydrids, chaoborids and chironomids and even sorne odonate genera (Ward, 1992; Williams, 1996). Although not ail taxa of insects are gencrally found in all temporary ponds and pools around the world, cenain groups like the chironomids and chaoborids are the exceptions in that they will opportunistically take aJvantage any habitat given ta them (Oehoney & LaVigne, 1981: McLachlan. 1981). Cladocera of the genus Daphnia can also be found in temporary ponds, as weil as severa! genera of Copepoda (Williams, 1987; LaBerge & Hann. 1990). Several ather groups, such as, bivalves, gastropods and ostracans can be faund. but these tend ta be less common and geographically restricted to certain regions around the globe (McKee & Mackie, 1981: • Brown, 1985; Williams, 1987; Hombach et al., 1991). Amphibians can be round in great numbers in certain ephemeral ponds (Wilbur, 1987: Blaustein et al.. 1996). Although groups of taxa are found in ternporary ponds and pools, the species present within each habitat will Jiffer with geographic location. Therefore, it may be very difticult to compare species ofone tcmporary pool to anather, especially on different continents. since bath groups af species are maybe under dissimilar climatic and environmental pressures and could have distinctive life cycle or survival strategies. Comparisons made from one pool or pond to another should he made on habitats that are relatively close to one another and share similar climatic conditions (Williams, 1985). The harshness oftemporary ponds and pools, namely the dryness that these habitats experience, will determine which types of organisms can survive in them. But the hydroperiod of a habitat, that is, how long a basin retains water, is perhaps the most important factor influencing which taxa oforganisms will be able to live in one pool or pond • and not another (McLachlan, 1981; Williams, 1996). Even though ail temporary water 9
inhabitants use sorne kind of adaptive strategy to overcome desiccation, not aIl can utilize • every habitat in arder ta complete their life cycle. In other words, sorne organisms have longer developmental times than athers, so ifit takes them too long to mature, their aquatic environment may disappear and they become stranded and die (Williams, 1987). This is especially true for trichopteran larvae and odonate nymphs since these immature forms are unable la survive desiccation (Ward, 1992~ Bayly & Williams, 1973). So shoner lived temporary ponds and pools will contain only organisms that can complete their litè cycle before the water disappears (short generation), and longer lived systems will contain both short and longer generation taxa. This has been seen in many studies where species richness typically increases as the length of the tlooded period in ponds increases (Collinson et al., 1995: Bluustein et al., 1996). There is also a progressive increase in predator species richness as habitat duration increases (Schneider & Frost, 1996). since predators are amongst the lasl groups of organisms to appear in ephemerai systems. Hence, the longevity of a habitat will determine whether or not a predator will be present (Schneider & Frost. 1996). Ephemeral pond and pool studies have shown the occurrence of a weakly detined • succession on the part ofthe fauna living within these systems (Williams, 1985). Succession, detined as the pattern of changes in community structure and composition with time following a perturbation (Connell & Slatyer, 1977: Meintjes, 1996), is commonplace in lemporary waters. Much of the fauna of temporary ponds and pools display a characteristic successional pattern (Bayly & Williams, 1973). Following the perturbation, in the case of lemporary systems this is the drying event, certain groups oforganisms will appear tïrst then followed by other taxa and so on. The earliest organisms to appear are those which have overwintered as eggs or larvae in the empty pond or pool basin and are the first to utilize the newly fùled environment. Many of these taxa are herbivores and/or detritivores and are able to feed on plant material found within the basin (Williams, 1987). Examples of such ùrganisms are Copepoda, Cladocera, Anostraca, Notostracta, Conchostraca, sorne Bivalvia and Gastropuda and some Trichoptera, such as the limnephilids (Williams, 1987: Ward, 1992). These organisrns are then closely followed by other detritivore or tilter-feeding taxa • with slightly longer life cycles, such as ephemeropterans and the dipteran chironomids and 10
chaoborids (Ward, 1992). Predaceous taxa like Odonata, Hemiptera, Coleoptera and • Amphibia will be the latest to appear in ephemeral habitats (Williams, 1987), but the hydroperiod of the pond or pool will determine whether or not certain taxa, especially predaceous forros, will he found in them. The longer a basin remains wet, the more "chance" a specifie predator can exploit the habitat (Schneider & Frost, L996).
Scone of previous studies on temporary ponds and pools
Many studies conducted on temporary freshwater habitats have been restricted in their scope ofstudy. Many studies discuss temporary habitats with reference to particular plant or animal groups (Williams, 1995) while ignoring the rest of the biotic community. Taxon specillc groups and ecological processes have been examined in detail (King et al., 1996). Quantitative experiments on processes such as adaptation mechanisms, biotic interactions, growth rates, detrital uptake, life-history strategies and colonization methods have been done
aL lèngth on ephemeral habitats (McLachlan, 1981: Batzer & Wisseger, 1996: Williams, • 1996). The main problem with many of these studies is that the entire faunal community of many of these temporary habitats is still unknown. It is doubtful that researchers have assumed that the same species and interactions found in temporary habitats are identical to better known permanent systems; but many of them have yet to determine the complete
community composition of these ephemeral systems. As King et al. (1996) state Il •••our understanding of the ecology and evolutionary history of ephemeral pool communiùes is
hampered by a paucity of such basic data as species composition of pool assemblages. Il This lack of basic community knowledge has aIso special implications for temporary habitats which support endangered species. The scarcity of information about their ecology makes it difficult to give sound advice about the management of ephemeral habitats (Collinson et al., 1995). It would seem that many of the quantitative studies done may he premature and perhaps even uninformative (Fryer, 1987). Moreover, it seems peculiar that the collection of quantitative data is done without even understanding the biological processes, species • diversity and ecological interactions of organisms found in temporary habitats. In order to Il • make quantitative data meaningful, qualitative studies must precede them (Fryer, 1987). This is especially true in the case ofvernal pools and ponds in eastern Canada, since examinations of entire communities have yet to he done.
Fatmal collection methods There is no defmitive or proper way in which to collect sarnples from shallow and temporary aquatic habitats. In fact, no acceptable quantitative methods have yet been devised to determine absolute numbers of organisms in these ever changing habitats. For exarnple, core-type samplers and dredges cao he used to measure the number of organisms per unit arca ofsubstrate (Welch, 1948; Edmondson, 1971; Lind, 1985); unfortunately these samplers are extremely disruptive to biota in small systems and may not be effective in habitats which are drying up progressively. A suction sampler devised by Boultan (1985), which consists of a pump that removes water lnd sediment from a habitat and tilters out the organisms. has been applied for shallow lentie systems. But again the difficulty with this sampler is that it can he extremely damaging to small systems. Activity traps can be used to eolleet organisms, • but these are only usefuI in capturing fauna that are highly mobile (Edmondson, 1971). In faet. many benthic forms do not even swirn but remain on the substratum. Dip or pond nets have been utilized regularly to colleet benthos and nektonic organisms in temporary habitats. These nets perform weil in vernal pools where water volumes nuctuate and have been used to collect anostracans (Donald, 1983), insect taxa found on the water surface and on the substratum (Dehoney & LaVigne, 1981; Deluechi, 1992: Nilsson & Soderberg, 1996), as well as other crustaeean, molluscan and amphibian groups (Schneider & Frost, 1996). Triangular and O-frarne sweepnets dragged on the bottom ofbasins colleet a good number ofhenthos and other mobile organisms that would otherwise he rnissed by sorne of the previously mentioned samplers (Edmondson, 1971: Schneider & Frost, 1996). Nets ofmesh sizes of 1 mm! are the standard (Collinson etal.. 1995), and these are swept back and forth in the pools and ponds with a certain number of strokes (Edmondson, 1971). Dip nets are useful in determining what organisms are present in the • habitat, but they are not adequate to ascertain the numbers oforganisms present. 12 • Materials and Methods Choice and description of temporarv vernal pools
A total of ten pools was chosen on the western portion of the island of Montreal. These pools were chosen based on two major criteria: they had to be formed by water from snow-melt and/or spring rains and they were not to be connected or immediately proximal to uny permanent water body. These pools were aIso selected based on anecdotal knowledge by various people who knew their location and their temporary nature (Bider, pers. comm.; Lewis, pers. comm.; Watson, pers. comm.).
Six pools were situated in Ste-Anne-de-Bellevue (45 0 N, 73 0 W) with (WO located in the Stoneycroft Wildlife Area and four in the Morgan Arboretum. Five pools were initially choscn in the Morgan Arboretum, but because of the uncertainty ofthe temporary nature of pool #1 (Ml), sampling was discontinued and tbis pool was omitted from the project. The last four pools were found near a park in the Village of Senneville (see Appendix 1 for exact • location of pools). Pools in the same locality tended he similar in respect to the vegetation sUITounding them and the environrnental conditions to which they were exposed. Morphometric and substrate characteristics of individual pools is presented in Appendix 2.
Sampling period
Biweekly sampling was done in the afternoon (12:00-18:00) hetween April 9 and July 23, 1998. Sarnpling dates for the flfSt three weeks differed amongst pools; Morgan Arboretum pools were sampled on April 13, 15 and 19: Senneville pools were sampled on April 9, 13, 16 and 21; and Wildlife Area pools were sarnpled on April 12, 15 and 19 (it was later determined that these two pools had thawed roughly six days before their first sampling date). There were two reasons for tbis: (i) sampling ooly commenced when pools were completely free of ice and hence certain pools could he sarnpled earlier than others, and (li) • time constraints, due to early darkness in the spring, prevented sampling of ail pools on the 13
same date. After April 21 aIl pools were visited on the same day. Sampling continued until • desiccation; pools were considered dry and no longer visited iftbey remained dry one week following the last sampling date when water was present. In addition, desiccated pools were visited only if the total amount of rainfall for a day exceeded 20 mm. Since the pools dried up at various times during the season and were replenished by rains only for a tew weeks in late June and early July, there were gaps in sampling periods
SamplinQ methods
A small "aquarium" net measuring 15cm x 12.5cm and aD-frame dip net 25cm x 31cm were utilized ta collect invertebrates in the pools. Both nets had a similar cross-thatching mesh pattern with apertures less than 0.25 mm wide. When the maximum water depth exceeded 15em the larger D-frame frame dip net was utilized and eonversely when the maximum water depth was less than L5em the smaller net was used. Air and water temperatures, maximum water depth, maximum length and width were • recorded for eaeh pool on each sampling date. If a pool dissociated itself into smaller pools as it dried, the parameters were measured for each of the smaller individual pools. Sînce there are no standardized sampling techniques tor collecting organisrns in vernal pools, methods adopted in this study anempted ta sample a large area of each pool without greatly diminishing the population of organisms found within them. A maximum of ten one-meter sweeps were made in each pool; these sweeps were performed bath near the edge and middle of the pool. As pools became drier and smaller in area, the number of sweeps decreased as to sample halfofthe surface area ofa pool. During desiccation, ifa pool separated itself into smaller separate pools, the number of sweeps in each smaller pool permitted sampling of half of its surface area; the total number ofsweeps for tbese smaller
pools did not exceed ten. Due to the variation in (i) pool sizes (Appendix 3) and (ü) sampling procedures, quantitative presentation of the data obtained is limited. During sampling, nets were dragged against the bottom of each pool ensuring the • collection of organisms on the bottom and at the water surface. Contents of nets were then 14
transferred into a bucket of water; large detritus was washed to remove any organisms and • discarded. Contents of the bucket were then fùtered through the aquarium net to remove water, and sarnples were then placed in appropriately labeled containers containing 80% ethanol. !\1aterial was then brought back to the lab where it was seived in a U.S. Standard Sieve Series Mesh no. 35 to remove small detritus. This material was then examined under a dissecting microscope and organisms were separated from remaining detritus and placed into vials containing 80% ethanol.
Macroinvertebrate identification
Organisms were later enumerated and identified to genera or species where possible. Keys round in Pennak (1978) and Merriu and Cummins (1978) were used initially to identify organisms down to family or genus and then other pertinent keys were applied to each taxon. The following keys were used for the identification of the various organisms
l:l>Uected: Diptera (Cook, 1956; Lake, 1969; Saether, 1970: Pennak, 1978: Wood elal., 1979; Peters, 1981: Oliver & Roussel, 1983; Vockeroth & Thompson, 1987): Coleoptera (Dillon & Dillon, 1961: Usinger, 1968: Malcolm, 1971; Smetana, 1988): Hemiptera (Hungerford, 1977: Slater & Baranowski, 1978);Trichoptera (Wiggins, 1996): Odonata (Walker & Corbet, 1975): Ephemeroptera (Edmunds et al., 1976); Eubranchipoda (Pennak, 1989); Isopoda (Williams, 1972): Amphipoda (Boustield, 1958; Pennak, 1989)~ and Mollusca (Burch, 1975; Burch, 1989). Many taxa were identified only to genera since keys were unavailable to identify them to species. AIso, sorne specimens were tao small to he reliably identified such as, early Culicidae instars, Tipulidae larvae and Odonata nymphs. Specimens of Mochlonyx (Chaoboridae) could no t he identified to species since no larval characteristics have yet been
round lO differentiate between larvae of M. cinciptes and M. velulinus (Saether, 1970; Borkent, 1981). • 15 • Results and Discussion A list ofall taxa found, the total number oforganisms eolleeted and their distribution among the study pools is given in Table 1. The seasonalities ofmajor taxonomie groups and of individual species are shown in Figs. 1-63. In addition. the two more abundant taxa collected. Culicidae and Chironomidae, were examined in greater detail for eaeh pool: the relative abundanee ofeach genus or speeies on specifie sampling dates are presented in Figs. 64-81. Finally, the total number of taxa collected per pool is shawn in Fig. 82.
Community composition of temporarv pools
68 different taxa were collected and identified from the ten temporary snow-melt pools (Table 1). AU taxa colleeted have been recorded previously in eastem North America. and pools in the same geographic area tended to have similar taxa.
• Culieidae
Ail species of Culicidae collected are recorded in Quebec (Maire & Aubin, 1980: Wood et al., 1979) and were generally found in at least one pool in Senneville, the Wildlile Area and the Morgan Arboretum (Table 1). Only Aedes diantaeus, Ae. intrudens and Ae. punetor were restricted to Morgan Arboretum pools, whereasAe. communis,Ae. excrucians, Ae. provocans and Ae. stimulans were eollected in aIl poollocaliùes. It is not surprising to observe such a distribution for these organisms since vernal pools represent one ofthe most commonly used habitats by mosquitoes in the Nearctic region (Bay, 1974: Batzer & \Vissenger, 1996). Mosquito larvae are usuaIly found in small shallow habitats where water movement is minimal, such as vernal pools in wooded areas or in tields (Happold, 1965; Clements, 1992). Their distribution in these ephemeral habitats is due to the oviposition behaviour offemales; they lay eggs in existent pools in early spring or in dry depressions that • are replenished with water the following spring (Horsfall. 1956; Wood et al., 1979; 16
Clements. 1992). They can aIso he found in pools that have hydroperiods as short as ten days • (Karadatze, 1979). Therefore, il would seem that the study pools provided an excellent habitat for mosquito development.
Chaoboridae
Ali species of Chaoboridae collected (Table 1) have been recorded previously l'rom Quebec Chironomidae Ali genera of Chironomidae collected (Table 1) have been previously recorded in Quebec or in eastem Canada (Oliver et al., 1990). As shown in Table 1, Lim.nophyes spp. were the ooly chironomids to he collected in aU Morgan Arboretum and Senneville pools. Chironomus spp., Corynoneura spp., Phaenopsectra spp. and Zavrelimyia spp. were also collected in sorne of the Morgan Arboretum and Senneville pools. Hydrobaenus spp. were the only chironomids to be found in WildIife Area and Morgan Arboretum pools. Doithrix spp. were collected only in Morgan Arboretum pools, whereas Psectrotanypus spp. were round only in Senneville pools. The remaining taxa were more restricted in their distribution in that each was colleeted in only one pool during the entire season. • Chironomid larvae live primarily in freshwater systems and are round in every 17 conceivable permanent or temporary habitat (Oliver & Roussel, 1983). Most of the taxa • collected in this study are usually found in the shallower regions of lentic permanent waterbodies and quieter areas of flowing waters (Oliver & Roussel, 1983; Oliver et al., 1990). As demonstrated in the next section (Abundance of taxa collected), many of the genera round do not specifically utilize vernal pools and therefore were collected in very low numbers. It is possible that severa! ofthese genera were "accidentally" introduced into these pools. Dixidae, Syrphidae and Tipulidae The remaining dipteran familles were collected ooly in Morgan Arboretum and Senneville pools (Table 1): these are common to eastern Canada and can be found in many types of freshwater habitats (Peters, 1981: Vockeroth & Thompson, 1987). Tipulidae and SYrphidae can be found in moist soils and in shallow lentie systems with deeaying organic matter: Dixidae are usually found in lotie habitats (Nowell, 1951: Peters, 1981; Vockeroth • & Thompson, 1987). Ail Senneville and Morgan Arboretum pools had large amounts of decaying plant matter (Appendix 2) and therefore provided an excellent habitat for tipulids and syrphids. Coleoptera Ali genera of Coleoptera collected (Table 1) have been previously recorded in Quebec (Alaire & Leclaire, 1988; Smetana, 1988; Larson & Roughley, 1991; Roughley, 1991 ). The Dytiscidae, with the exception of Colymberes spp. larvae and Hydroponls spp., were colleeted only in the Morgan Arboretum and Senneville pools (Table 1). Acilius spp. and Agabus spp. larvae were found in most pools, whereas Dytiseus spp. larvae appeared to he restricted to Senneville pools. AlI other Dytiscidae were collected in only one or two • pools. A similar pattern was seen for the Hydrophilidae, except for Anacaena limbata, 18 Berosus striarus and Helophon,s spp., where most taxa were collected only in Morgan • Arboretum and Senneville pools. Hydraena, the only taxon of the Hydraenidae, was restricted to three Morgan Arboretum pools. These Coleoptera usua1ly overwinter as adults in sorne permanent body ofwater and disperse in early spring in search for newly formed pools (Smetana, 1988; Larson & Roughley. 1991: Williams. 1996). They take advantage of the abundance of food found in vernal pools and also use them as oviposition sites (Nilsson & Soderstrom, 1988; Smetana, 1988: Larson & ROllghley. 1991). They prefer small shallow water bodies with liule water ClIrrent and rich vegetation and can he quite abundant in temporary pools round within woodlots (Young, 1954; Dillon & Dillon. 1961: James, L96L Alaire & Leclair. 1988: Smetana, 1988; Boobar et al., 1996). These conditions were met by most Morgan Arboretum and Senneville pools and therefore were ideal habitats for these beetles. Hemiptera • The Hemiptera collected in the study pools (Table 1) are common ac..ross North America (Hungerford. 1977; Slater & Baranowski, 1978). Similar ta the Coleoptera, Hemiptera adlllts overwinter in permanent systems and disperse in the spring into vernal pools (Slater & Baranowski, 1978; Williams, 1996). Many Hemiptera are collected in temporary ponds and can he quite common in these habitats (Baldwin et al., 1955: James, 1961). It is surprising that few Hemiptera were collected in the study pools. These insects are good swimmers and fliers (as adults) and perhaps evaded capture during sarnpling. This was especially evident in the case ofthe Gerridae, since many were seen in all pools on every sampling date, yet few were captured. Therefore, the Herniptera are probably underrepresented in Table 1. Trichoptera • Two genera ofTrichoptera were collected in the study pools (Table 1) and these are 19 knawn ta aecur in eastem Canada (Schmid, 1980; Wiggins, 1996). • Limnephilus spp. were found in aIl pool localities whereas Ironoquia spp. were callected only in pool 53 (Table 1). These taxa can utilize tempGrary pools and in fact, /ronoquia spp. are restricted to these habitats (Williams & Williams, 1975; Wiggins, 1996). The females of both genera actually return to dry basins ta oviposit (Wiggins, 1996; Williams, 1996). Odonata Odonata nyrnphs were collected only in pools W1and S1(Table 1). Odonata utilizing wmporary pools need habitats that remain wet far 2-3 months in arder to complete development, since nymphs are not able survive drought (Bayly & Williams, 1973). It is llnlikely that specimens l'ound in pool W 1would have completed development since they did not appear until one week before drought. None was collected from most study pools since many of them did not remain wet for more than two months. Sympetrum obtnisum is one • of the few dragontlies that can utilize temporary habitats in Quebec, and is usually found in woodland ponds and in gravel pits (Roben, 1962; Walker & Corbet, 1975). It is not sllrprising ta have callected sorne in pool 51 since tbis pool appeared to he an abandoned quarry. Epherneroptera One Ephemeroptera genus was collected in pool S3 during the entire season (Table 1). Although cenain species of mayflies are capable of utilizing temporary habitats (Bayly & \Villiams, 1973), no Centroptilum spp. are known to use vernal pools. This genus is usually associated with quiet portions of streams and rivers (Edmunds et al., 1976) and so their presence in pool 53 was surprising. • 20 • Anostraca One species of Anostraca was collected; it was found in the WildIife Area and Senneville pools (Table 1). E. bundyi is comman in eastern Canada and has been collected previously in the Wildlife Area pools (Dexter9 1953;). ft is very comman in vernal pools and is restricted to temporary habitats (Daborn, 1976; Pennak, 1978; Williams. 1987). Unlike the previously mentioned insects which ean disperse aetively, E. bundyi disperses passively. Anostracan eggs ean he transporated to other pools by wind or waterfowl (Pennak, L978: Graham, 1994). Anostraean eggs can pass in a viable condition through the gut of waterfowl (Donald, 1983); tbis is perhaps the main method ofcolonization for E. bundyi in vernal habitats. Mallard ducks (Anas plaryrhynchos) were found in Senneville pools on one sampling date and are known to utilize Wildlife Area pools (Bider, pers. comm). The lack of E. bundyi in Morgan Arboretum pools could he explained by the faet that the tree cover surrounding these pools is too dense for waterfowl. • lsopoda Caecidora forbesi was the only species of Isopoda collected; it was round in Senneville and Morgan Arboretum pools (Table 1). This species is widely distributed in the eastern portion of North America and oeeurs in temporaryponds (Pennak, 1978). The eggs of this organism are also dispersed passively by wind (Pennak, 1978) and tbis could explain their wide distribution in the study pools. Amphipoda The amphipod, Crangonyx minar, was eollected ooly in pool M5 (Table 1). This speeies has bèen recorded in eastern Canada and has been found in streams, ditches and temporary woodland pools (Bousfield, 1958: James, 1961). Similarly, the dispersal of this • organism is passive with wind or waterfowl carrying resistant eggs from one pool to another 21 • (Boustield, 1958). Its occurrence in only one pool is puzzling. Gastropoda Four taxa ofGastropoda were collected in the study pools~ the majority were round in the Morgan Arboretum and Senneville pools but Gyraulus spp. were also found in Wildlife Area pools (Table 1). Ail genera and species collected have been previously recorded in Quebec (Clarke, 1981). These snails are all pulmonates and can utilize ephemeral pools since they are capable of leaving the habitat or aestivating during drought (Pennak, 1978: Williams, 1985). In faet, Aplexa elongata demonstrates this aestivating behaviour and is usually found in temporary habitats (Clarke, 1981: Brown, 1982). In temporary pools, snails can fonn an important component of the invertebrate rauna and therefore are quite common in vernal pools (Dewitt, 1955). • BivaIvia Sphaerium occidentale was the only species of Bivalvia collected and il was restricted to Senneville pools (Table 1). It has been previausly recorded in Quebec and is cxclusively collected in temporary habitats such as ditches, swamps and shallow ponds (McKee & Mackie, 1981: McKee & ~Iaekie, 1983). This species is more amphibious than any other bivalve in North America in that it cao withstand drought through aestivation (McKee & Madcie, 1983). It is usually dispersed from one habitat to another by waterfowl (Harnbach et al., 1991). This could explain ilS presence in Senneville pools since mallard ducks (Anas platyrhynchos) were seen there. Abundance of taxa collected It proved ta he difficult to sample these temporary habitats due ta their changing • nature. From one sample date to the next, water levels and volumes tluctuated in each pool 22 as they dried up. These habitats changed so rapidly that it was futile to attempt an absolute • number oforganisms per unit area or volume ofwater. For this reason, only the total number of organisms of each taxon collected in each pool during the entire sampling period is presented as data (Table 1). The Culicidae was the most abundant (68.7%) of aIl invertebrates collected; the Chironomidae was second (10.7%), followed by the Mollusca (8.2%) where bivalves were the bulk (7.1 %) oCthis group. Anostracacomprised 3.6% ofthe total community, followed by the Isopoda (2.7%), Chaoboridae (2.7%) and Coleoptera ( 1.7 o/e ). The remaining taxa each acco unted for less than 1% 0 f the entire poo1co mmunities. Il is not surprising that the Culicidae and Chironomidae dominated the invertebrate communities in the study pools. In the Nearctic region, the larvae of these Diptera are often the numerically dominant residents in vernal pools (Bay, 1974: Tokeshi. 1995: Batzer & Wissenger, 1996). Also, the Culicidae can utilize a large variety of vernal habitats and coupled with their great dispersal ability, can he found in almost any type of temporary pool (Wood et al., 1979) . • Examination of the data more closely (Table 1) reveals sorne interesting patterns. Culicidae Although certain species of Culicidae were round in both Senneville and ~lorgan Arboretum pools, their relative abundance was not necessarily similar in the different pool localities. Ae. canadensis, Ae. cînereus, Ae. communis, Ae. diantaeus, Ae. excrucians, Ae. intrudens andAe. punctorwere an round in greater abundance (>80%) in Morgan Arboretum pools (Table 1). Ae. euedes and Ae. stimulans were found in greater numbers in Senneville pools and in pool M5. Ae. provocans was collected in greater abundance in pool M5, whereas Ae. vexans was found in sirnilar numbers in bath Morgan Arboretum and Senneville pools. Fewer Culex specimens were collected, and most were found in pool S3: however, 250/0 of all specimens of ex. resnlans were found in pool M5. Only 15 specimens of An. quadrimaculatus were collected and most were found in pool M5. • AIl study pools seemed to he suitable habitats for the Culicidae but the distribuùon 23 of individual species differed slightly based on habitat preferences (Wood et al., 1979). Ae. • canadensis, Ae. cinereus, Ae. communis, Ae. diantaeus, Ae. intrudens and Ae. punctor are ail species that prefer pools which are heavily shaded by plant cover such as conifers or shrubs (Breeland & Packard, 1963~ Maire et al., 1978; Maire & Aubin, 1979: Wood et al., L979~ Laird, 1988). This is perhaps the reason why these species were most numerous in Morgan Arboretum pools (Table 1) since the pools were shaded throughout the season. ln contrast, Senn~ville pools were shaded oruy after the deciduous trees grew leaves and Wildlife Areas pools had no tree cover. AIso, severa! of these species are regularly round in association with one another. Ae. canadensis, Ae. cinereus and Ae. punctor tend to be present together in the same pools: similarly, Ae. communis, Ae. dial7taeus and Ae. intrudens are generally collected concurrently in pools (Wood et al., L979; Maire & Aubin, 1980). ln facl, sorne species need these associations in order to survive. For example, Ae. diantaeus needs the presence ofAe. comnumis for its survival; unlike other Aedes species which feed on bottom debris, Ae. diantaeus gathers stray food particles stirred up by Ae. communis larvae (Wood et al., 1979). Therefore, the presence of Ae. communis or perhaps other • substrate-feeding species is essential for Ae. diantaeus. Ae. cinereus and Ae. communis were peculiar in their abundance in Morgan Arboretum pools. Ae. cinereus was especially abundant in paol MS, even though ail Morgan Arboretum pools were similar in shading (Appendix 2). Ae. cinereus is one of the last Aedes species ta appear in the spring (Wood et al., 1979) and is likely to he abundant in pools with longer hydraperiods like pool M5. Ae. communis was absent in pool MS; tbis is surprising since the Morgan Arboretum pools were similar and relatively close to one another. A possible explanation is that Ae. communis was replaced by Ae. stimulans in tbis pool. In the present study, when one species was abundant in a pool the other was callected in low numbers; both species have similar seasonalities (Figs. 2 & 3) and per~:aps similar ecological niches. Aedt1s stimulans is generally found in woodIand pools near edges oflakes and where silver maple (Acer saccharinum) is the dominant tree species surrounding the pools. This • maple canopy provides heavy shade to soil underneath and females choose these areas ta 24 • oviposit (Wood et al., 1979). Senneville pools were bordered by a large number ofmaples and Ae. stimulans was most abundant in these pools (Appendix 2). Very few were collected in most Morgan Arboretum pools except for pool MS; this pool was surrounded with more roaples and various other deciduous trees than the other Morgan Arboretum pools. Ae. euedes is usually found in vernal pools in association with Ae. stimulans (Wood et al., 1979). Ae. euedes was found in Senneville and Morgan Arboretum pools but was most numerous in pools (especially pool MS) where Ae. stimulans was present (Table 1). Ae. provocans and Ae. vexans can be found in any type ofground pool in the presence or absence of trees. They have been collected in densely forested areas and open marshlands (Wood et al., 1979); their appearance in ail poollocalities may he due ta their lack ofhabitat specificity. Generally, An. quadrimaculatus, Cx.pipiens and Cx. restuans arc found in puddles, ditches and tcmporary pools, whereas Cx. territans is more common in permanently water-tilled marshes (Wood et al., 1979). This may he why low numbers of ex. territans were collected (Table 1). Anopheles and Culex larvae appear later in the spring and early summer than Aedes species (Wood et al., 1979), therefore will be found in pools with longer hydroperiods. Ail. quadrimaculatus and Culex species were relatively abundant in pools 53 and M5 (Table 1), that is, the pools with the longest hydroperiods. Chaoboridae The Mochlonyx species comprised the bulk ofthe Chaoboridae collected; most were found in pool M5 (Table 1). Mochlonyx species can he quite abundant in pools surrounded by dense plant cover (O'Connor, 1959). In the present study, pool MS was surrounded by thick vegetation and had the largest number ofspecimens. C. americanl.ls is known to utilize temporary ponds, whereas C. flavicans is mainly found in lakes (Saether, 1970); this may be the reason why the latter species was collected in low numbers in the study pools. • 25 • Chironomidae Phaenopsectra and Hydrobaenus were the most abundant chironomid genera collected (both 39.60/0) (Table 1); each was found in large numbers in only one pool (Wl and MS respectively). Chironomus spp. were the second most abundant (12.9%) and were slightly more numerous in Senneville pools. Limnophyes spp. (4.9%) were collected in both Senneville and Morgan Arboretum pools. All other taxa were collected in low numbers, and each accounted for less than 2% of the entire chironomid community. Relatively titde is known about the habitat preferences of many of the chironomids collected in this study. Therefore, the relative abundance of each taxon will be examined more closely than their occurrence in the various poollocalities. Lentic shallow systems may often support high densities and biomass ofchironomids and in small systems a single species can dorninate the entire chironomid community (Tokeshi, 1995). This was evident in study pools M5 and Wl where Phaenopsectra spp. and H.vdrobaenus spp. were collected in great numbers (Table 1). Both genera can be found • inhabiting shallow regions of rivers, lakes, ponds, puddles and ditches, but are usually associated with spring pools (Grodhaus. 1980; Cranston et al., 1983). Il is not surprising that they were abundant in the present study. Chironomus spp. occur in all types of freshwater habitats but are more common in lentic systems (Oliver & Roussel, 1983). Chironomus spp. take advantage of a varietyof temporary habitats and can he found in abundance in these systems (McLachlan, 1981; Batzer & Wissenger, 1996). This taxon is one of the most abundant chironomids collected and was quite common in Senneville pools (Table 1). Limnophyes spp., the next most abundant taxon collected differs from the others in that larvae of most species are semi-terrestrial (Cranston et al., 1983; Pinder, 1995). They are found near water and usually associated with wet soils (Pinder, 1995). Larvae ofDoithrix spp. and Smùlia spp. are aIso semi-aquatic orterrestrial (Cranston et al., 1983; Pinder, 1995). Due to the lack ofappropriate keys, it was not possible to identify them to species; perhaps • specimens collected were aquatic taxa or terrestrial species that were inundated. 26 The remaining Chironomidae were collected in low numbers during the eotire season. • Few Corynoneura, Larsia. Polypedilum, Psectrotanypus and Zavrelimyia specimens were collected even though they are common in nearly ail types of freshwater habitats including ditches, small standing waters and smail detrital filled basins (Cranston et al., 1983: Fittkau & Roback, 1983: Oliver & Roussel, 1983). In contrast, Eukiefferiella, Harnischia and Pseudochironomus species are more common in flowing water, and sorne larvae inhabit soft sediments of lakes and rivers (Oliver & Roussel, 1983: Pinder & Reiss, 1983: Oliver et al., 1990). Di.xidae, Syrphidae and Tipulidae Few specimens of these three Diptera familles were collected (Table L). Except for the Syrphidae in pool S4, these dipterans were generally equally abundant in all Morgan Arboretum and Senneville pools. Perhaps the reasan why Eristalis spp. were more abundant in pool S4 was because trus pool was a dump for discarded tree branches and grass clippings. • Eristalis larvae tend to be round in habitats where decaying matter is abundant (Vockeroth & Thompson, 1987). Dixidae were collected in Low numbers since they prefer lotie systems (Nowell. 1951). The Tipulidae collected were tao small to be identified; aquatic and terrestrial taxa are known ta occur in vernal pools and t100ded lands, however the latter is usually collected in lower numbers (Pritchard & Hall, 1971: ~teats, 1972). This mayexplain why few Tipulidae were found in the pools. Coleoptera The Coleoptera made up a very small portion of the pool communities (Table 1). Acilius spp. larvae were the most abundant (30.3%), and these were mast numerous in Senneville pools. Anacaena limbata and Hydraena spp. (bath 13%) were the second most abundant, with the latter species collected only in Morgan Arboretum pools. The remaining • genera were not very abundant and were found in most poo11ocalities. More beeùes were 27 collected in Senneville pools (64.5%) than in the Morgan Arboretum pools (32.20/0). • Adult beetles disperse in the spring from permanent water systems to vernal pools in order to feed and lay eggs (Smetana, 1988; Larson & Roughley, 1991; Williams. 1996). Since the Senneville pools were doser to the Ottawa River than the Morgan Arboretum pools, the Senneville pools were more likely to he colonized by beetles. Coleoptera are llsually an important component of vernal pool communities (Alaire & Leclair, 1988; Smetana, 1988; Nilsson & Soderberg. 1996). Their low numbers in the study pools could be due to the ability ofadults to evade capture. It is likely that many of the genera collected àre underrepresented in Table 1. Hemiptera Hemiptera were collected in law numbers (Table 1) and may have evaded capture during sampling. • Trichoptera, Odonata and Ephemeroptera The number of organisms collected for each ofthese taxa was extremely law (Table 1). They were collected mainly in one poollocality or in one pool. The Trichoptera and Odonata collected are known to utilize vernal pools. whereas Centroptilum spp. (Ephemeroptera) are usually not found in these habitats (Robert, 1962; Walker & Corbet, 1975: Williams & Williams, 1975; Edmunds et al., 1976; Wiggins, 1996). The study pools may not have been ideal habitats for the Trichoptera and Odonata since the hydroperiod of most pools was tao short to allow these taxa to complete their aquatic life stages. Anostraca, Isopoda, Amplùpoda, Gastropoda and Bivalvia No apparent patterns can he discemed about the abundance ofspecimens collected • for the remaining taxa (Table 1). Generally, each taxon was abundant in only one or two 28 pools or in one poollocality. The differences in abundance of these taxa in the various pools • maybe due to the acùYÎties of waterfowl Ce.g., Anostraca & Bivalvia) and differing habitat characteristics. T~mporal chanees in community composition At the outset. the term Ifwet period" needs to be clarified. Wet period is the time interval when a pool contains water until drought. The frrst wet period denotes when these pools were trrst tilled by snow-melt and spring rains until their frrst desiccation. The second wet period is the post-drought period and includes the interval when pools have been replenished by rains until their second drought. Successive wet periods follow the same principle and these are numbered depending on how many times the pools have been replenished. For example, Wildlife Area pools had only one wet period since they did not lïll up again once they were dry. Other pools had two wet periods, and these included the Morgan Arboretum pool #3 (M3) and Senneville pools #2 and #3 (52 and 53). Pools that had • three wet periods were the Morgan Arboretum pools #2, #4 and #5 (M2, M4 and MS) and Senneville pool #1 (SI). Only Senneville pool #4 (54) had four wet periods. Taxa which had more than one genus or species are considered here and their seasonalities are shown in Figs. 1-63. These figures have been designed to show the similarities or differences in seasonality of various taxa between pools that conrain them. In addition, most ligures have an indication of peak abundance of certain taxa. Culicid species could not be reliably identified early in the wet periods due to the small sizes (early instars) of larvae: they have been identified as "uncertainll in the figures. The two more abundant groups, Culicidae and Chironomidae, were examined in greater detail: a comparaùve analysis of their taxa has been performed for most pools over time (Figs. 64-81). These figures help to illustrate the relaùve abundance oftaxa at specillc dates and changes in community composiùon with time. The percentages are based on absolute numbers; no modification ofdata has heen made. • As rnentioned earlier, a few Aedes and Culex specimens could not he reliably 29 • identified to species at the beginning ofthe season and immediately after drought. These are presented as "Aedes specîes" and"CuLex species" in Figs. 64-73; as lime progressed, the percentage of "unknowns" decreased and more specimens were named. AIso towards the end of the season (mid-May) fewer individuals were collected and these may he retlected as large percentages in the figures. Culicidae Many species ofAedes had similar and overlapping seasonalities. The tirst species to appear in ail pools was Ae. provocans (Fig. 1); it appeared immediate1y after spring thaw and was present till the tirst week of May (MS). It was one of the most abundant species collected immediate1y after thaw (Figs. 67-70). Specimens were collected for 10-14 days and generally peaked by mid-April. The next species to appear were Ae. eommunis and Ae. stimlilans: bath were present l'rom the second week of April until mid-May, and were mast abundant during that lime • period (Figs. 2,3 & 64-71). They were present in the study poals for 10-30 days. Ae. intrudens, Ae. puneror, Ae. euedes, Ae. exerucians and Ae. diantaeus appeared one week after the beginning ofthe sampling season (Figs. 4-8). Ae. intrtldens was callected for only one week and was found until the end of April (Fig. 4). Similarly, Ae. punetoT was collected only for Il days, and was present until the end of April (Fig. 5). Ae. euedes was present in most pools till the first week of May, but was collected for up ta 25 days in pool MS (Fig.6). Ae. excrucians and Ae. diantaeus were collected for 18 days and were absent in all pools after the frrst week ofMay (Figs. 7 & 8). The exact sequence of appearance for these species is difficu1t ta determine due to the problems in identit)ring early instars. However. Ae. euedes, Ae. excnlcians. Ae. intrudens and Ae. punctor seemed ta appear earliest since they were most abundant from mid-ta late April (Figs. 64-67). Ae. diantaeus seemed to appear later since it was most abundant from the last week of April till the first week of May (Figs. 64-68). • The next species to occur was Ae. canadensis (Fig. 9) and il was collected 7-10 days 30 aftel" thaw. In fact, in the Morgan Arboretum it dominated the culicid community l'rom the • end of April till the end of the first wet period (Figs. 64-67). It was also the only Aedes species ta appear in the f1l'st wet period and after drought. Interestingly, in pools M2 and M3, larvae were most abundantduring the frrst wet period, but were found in higher numbers after drought in pools M4 and M5. After the second week of July, Ae. canadensis was the dominant Aedes species in most Morgan Arboretum pools. The last Aedes species collected were Ae. cinereus and Ae. vexans (Figs. Lü & 11); they appearcd only after drought between sampling dates 29/6-9/7 and were most abundant during the tirst week of July. Culex species generally appeared later than most Aedes species (Figs. 12-14). ex. pipiens (Fig. 12) was the only Culex species to be round in bath frrst and second wet periods but were more abundant after drought. ex. restuans (Fig. 13) and Cx. territans (Fig. 14) \Vere collected solely after drought, and Cx. restuans was the dominant Culex species on ail dates (Figs. 72 & 73). The seasonal distribution of Culex species during the second wet period were similar. • An. quadrimaculatLls was present ooly after drought in the second wet period ofpools M5 and 54 (Fig. 15). The frrst appearance of adult mosquitoes in southwestem Quebec is usually around May 20 to June 1 (Wood et al., 1979). A warm spring can cause these insects to appear as much as three weeks eartier and such was the case in 1998 (Appendix 4). W 0 0 d et al. (1979) have divided the various genera of Culicidae into groups depending on their life history patterns of egg hatching and oviposition. The timing of oviposition and hatching helps to explain the occurrence and seasonality of various species in the pools. In the case of most Aedes species, the eggs overwinter and hatch in spring once pools are t1ooded. Larval development is completed before pools disappear, and adults oviposit in wet or dry depressions in the summer or early autumn. Most Aedes species are univoltine but a few, namely Ae. canadensis, Ae. cinereus and Ae. vexans, are capable of severa! generations if eggs have bp.en dried and subsequently reflooded (Wood et al., 1979). Culex and Anopheles • species differ in that adults are the overwintering stage, and lay eggs in pools only in spring 31 and summer (Wood et a!.. 1979). Therefore, Culex and Anopheles larvae will appear later • than Aedes larvae in the pools: this was observed in the study 'pools where Culex and Anopheles were collected in late spring and carly summer. Only the multivoltine Ae. cal1adensis. Ae. cinereus and Ae. vexans were collected in late spring and after drought. Aedes eggs must he "conditioned", that is, undergo a series ofenvironmental factors that will allow them to hatch (Karadatze, 1979). The eggs must tïrst be aerated, then submerged in water and exposed to a de-oxygenated environment in order to hatch (Happold, 1965: Karadatze, 1979: Laird, 1988: Clements, 1992). These are the stimuli that will promote hatching, but the requirements of individual species may differ and the exact timing of hatch will vary amongst species (Breeland & Packard, 1963); due 10 this the seasonalities of each species will differ. AIso, ternperature plays an important role in that certain species will hatch at lower temperatures than others (Karadatze, 1979; Wood eta!., 1979). Hatching not only varies between species, but also among pools. In this study, larvae were found at an carlier date in pools that had thawed sooner. such as the Senneville and WildIilè Area pools. The seasonality ofAedes in these pools would be ahead of similar species collected • in the ~lorgan Arboretum pools. Karadatze (1979) has shown that each Aedes species has different requirements for their eggs ta hatch. In addition, he has shawn that certain species will hatch earlier than athers. He round that Ae. communis, Ae. diantaeus, Ae. punctor and Ae. provocans are among the species that required the least amount of "stimulation" in arder to hatch. These species would be the frrst ta hatch in the spring, and Ae. provocans has been found to hatch at an early or partial thaw (Maire et al., 1978; Karadatze, 1979; Maire & Aubin, 1979~ Wood et al., 1979). Karadatze (979) aIso found Ae. stimulans would soon follow and that Ae. canadensis and Ae. cinereus should he among the latest species to appcar. He noted that the last species to appear would he Ae. vexans, since it requires warm water temperatures (10°C-15°C) in arder to hatch (Horsfall, 1956; Burst & Castello, 1969; Karadatze, 1979). Other studies on mosquitoes of vernal pools in Manitoba (Happold, 1965) and northem Quebec (Maire & Aubin, 1980) revealed similar results. These studies found that • Ae. communis and Ae. punctor were amongst the first Culicidae to appear in pools in late 32 • April and early May; by mid-May Ae. excrucians and Ae. intrudens were collected. and at the beginning of June Ae. vexans and Ae. cinereus were common. A similar successional pattern was seen in the study pools. In fact, the seasonalities ofAedes species in the vernal pools corresponded to what was observed by Karadatze (1979) Happold (1965) and Maire & Aubin (1980). Unfortunately, the hatching sequence for several species in the study pools could not he defmitively ascertained due to the large number ofearly instar larvae that could not he identified to species. These early instars could have potentially been any species, therefore it is almost impossible to pinpoint the exact lime when species first appeared. Nevertheless, the mosquitoes did appear early in the season. Under optimal conditions of food and temperature Aedes species can complete development in 10-21 days (Wood et al., 1979; Clements, 1992). 5uch was the case ofrnost Aedes species collected, except for Ae. vexans. Ae. vexans can complete development in tïve days ifwater temperatures are around 20°C (Breeland & Packard, 1963). This was witnessed in the study pools by the presence of pupae only tïve days after the pools had been rcplenished by summer rains. • The ecological reasoning for the successional pattern seen in Aedes species could he an attempt ta decrease competition among species. Clements (1992) has shawn that high levels of competition caused by high larval densities, results in longer developmental time, reduced pupation success and reduced pupal weight. It has been speculated that behavioural disturbances due to physical contact can cause them to have reduced growth rates (Dye, 1984: Clements, 1992). The feeding of fIrst instar larvae could be impaired by the repeated collisions of larger instar larvae in small volumes of water (Dye, 1984). Therefore, the hatching sequence seen in Aedes allows severa! species to utilize the same habit without the disruption of their own larval development. Culex larvae are usually found in pools in late spring and in the summer months (Wood et al., 1979): ail three species were collected during this period. ex. restuans and ex. territans are usuallycollected before ex. pipiens (Wood etal., 1979), yet the reverse was seen in pool 53 where aIl three species were collected. • An. qlladrimac~llatus is another species in which the adult females oviposit in pools 33 in the spring. Larvae usually appear in late spring and early surnmer (Judd, 1954~ Wood et • al., 1979) and such was the case ofspecimens collected in the study pools. Chaoboridae Mach/onyx spp. were the frrst Chaoboridae to appear and were arnong the tirst taxa ta be collected in the study pools (Fig. 16). In most pools they were collected l'rom the beginning of April, and were generally absent after the second week of May: the notable exception is pool M5 where they were present until the third week of May. They peaked in the middle of their season and were not l'ound after drought. C. americanus and C. flavicans were tÏIst collected in ail pools in the second week of May and were also present after drought (Figs. 17 &18). Their seasonal distribution appeared sporadic since very few specimens were collected. Mach/onyx species overwinter as eggs, and larvae emerge in ear1y spring ta teed on zooplanktan and early instars ofculicids (O'Connor, 1959: Saether, 1970). They are found • shortly after the appearance ofculicid larvae, and in eastern Canada can be collected in pools from the beginning of April tli mid-May (James, 1957~ O'Connor, 1959). This corresponds to the seasonality observed in the study pools. Not much is known about the seasonality of C. americanus in temporary pools. In permanent water systems, fourth instar larvae are the overwintering stage and adults emerge in mid May (James & Smith, 1958: Fedorenko & Swift, 1972). Perhaps the larvae found in the study pools arose from newly emerged adults which had dispersed from permanent waterbodies and laid eggs in these vernal pools. Chironomidae The genus Limnophyes was among the frrst of the Chironomidae to he collected in the study pools and was most abundant in mid-April (Figs. 19 & 74-81). In pool SI it was present until the tirst week of ivlay, but in ulner puois il WdS absent after the end of April. • A similar seas 0 nality was seen for Doithrix spp., since specimens were also collected 34 promptly after thaw and were most abundant in mid-April (Figs. 20 & 74-77); this species • was only round till the end of April in ail pools. Hydrobaenus spp. were another chironomid that appeared immediately after thaw, and were most abundant in mid-April (Fig. 21). Specimens were collected in high numbers only in pool Wl, and were present until drought. Chironomus species were also collected immediately afler spring thaw in pools M5 and Si, and were generally collected throughout the entire tirst wet period of pools; they were even found after drought in pool 53 (Fig. 22). This taxon was most abundant throughout the month of May, except for pool 53, where it was most abundant in mid-July (Figs. 77-81). In fact, in aU pools where Chironomus spp. were present, they constituted a large proportion of the Chironomidae community. Specimens of Phaenopsectra were also found in pool M5 promptly after thaw, and were present till mid-May (Fig. 23). They were collected aiter drought in pools M2, M5 and 5 land were mast abundant during the tirst week of July (Figs. 74, 77 & 78). In successive wet periods they dominated the Chironomidae community. The remaining chironomid genera were collected in low numbers making it difficult ta determine their actual seasonal • distribution. Sorne, such as Corynoneura spp., Eukiefferiella spp. and Psectrotanypus spp.• appeared early in the seasan soon after spring thaw (Figs. 24-26). In contrast, Larsia spp., Harnischia spp.. Polypedilum spp. and Pseudochironomus spp. were collected in late April and carly May (Figs. 27-30). Only Corynoneura spp., Psectrotanypus spp.. Smittia spp. and Zavrelimyia spp. were collected after drought (Figs. 24, 26, 31 & 32). Little is known about the ecology and life histories ofsevera! of the chironomid taxa collected in the study pools. Even less is known about the species utilizing vernal pools (Pinder, 1995: Tokeshi, 1995). Fonunately, the seasonalities of various subfamilies are known. and these can be useful in explaining the seasonal distribution of the taxa collected (Tokeshi, (995). Members ofthe Orthoc1adünae, whichinc1ude Doithrix, Corynoneura, Eukiefferiella, Hydrobaenus, Limnophyes and Smittia, have species which are capable ofrapid development and sharter lifecycles in temperate climates (Tokeshi, 1995). They are generally considered • to be cold-adapted, and hence should appear early in the season soon after spring thaw 35 (Oliver, 1971). Terrestrial and semi-aquatic species, such as Doithrix spp. and Limnophyes • spp.. are able to develop at very low temperatures and should he among the first chironomids ta appear (Pinder. 1995). Such was the case in the study pools where Doithrix and Linmophyes were amongst the first taxa collected after thaw, and were the most abundant chironomids collected early in the season. The other genera of Onhocladünae were also present during the frrst wet periods soon after thaw. Only Smittia spp. and Corynoneura spp. were found late in the season. appearing after drought; tbis could he due to multivoltism exhibited by many Orthocladünae (Tokeshi, 1995). The remaining chironomids collected belong to the Tanypodinae and Chironominae. In contrast to the Orthocladüoae, species of these two subfamilies are essentially thermophilious and need higher water temperatures for development (Oliver, 1971). Therefore, in vernal pools, these chironomids should appear later in the season as water temperature increases. This was observed for Larsia. Hamischia. Polypedilum. Pseudochironomus. Psectrotanypus and Zavrelimyia species: they were tirst collected in late April and early Mayor in pools which were replenished after drought. Few specimens of • these ta.x.a were collected, and because of their low numbers, they may not have been sampled earlier in the season. However, based on the literature, the seasonalities of these taxa appear to reflect what is known (Oliver, 1971). Even though Phaenopsectra spp. were collected early in the season, they were most abundant after drought, when pools were warm; higher water temperatures would provide more optimal conditions for tbis taxon. Chironomus spp. were also found saon ailer thaw~ this genus is one ofthe few Chironominae which cao grow and complete deve10pment at low water temperatures (Oliver & Roussel, 1983; Pinder & Reiss, 1983), hence their presence early in the season. Nevenhe1ess, Chironomlls spp. were most abundant from mid-May till the end of the sampling season, when water temperatures were at their highest. Severa! Chironominae and Taoypodinae, namely Chironomus spp., Phaenopsectra spp., Psectrotanypus spp. and Zavrelimyia spp., were collected after drought. It is known that these genera cao withstand desiccation and many produce cocoons before periods of • drought and freezing (Danks, 1971; Grodhaus, 1980; Oliver & Roussel, 1983; Pinder, 1986; 36 Pinder, 1995~ Tokeshi, 1995). In faet, cocoons containing larvae of Chironomus spp. and • Phaenopsectra spp. were collected in pools S3 and M5 a few days before first drought. Taxa collected after drought probably commeneed their development in the frrst wet period, cocooncd themselves before drought, and resumed activity once pools were replenished (Tokeshi, 1995). Also, cocooning could allow larvae which have not completed their dcvelopment in one season, to overwinter and resume deve10pment in the spring. This may explain the presence of Chironomlls spp. early in the sampling season. Dixidae, SYrphidae and Tipulidae Sînce few specimens of Dixidae, SYrPhidae and Tipulidae were collected, it is difticult to determine their actual seasonalities in the study pools. The Tipulidae seemed to appear immediately after thaw and were present only in the frrst wet period ofpools (Figs.85 87, 89,90 & 92). Dixella spp. were collected during the frrst three weeks ofMay (Figs. 88 90 & 92) and Eristalis spp. were collected from mid-April till the end of May (Fig. 33). • As seen in the study pools, Tipulidae are known to hatch immediately after thaw (Pritchard & Hall, 1971). Dixids usually overwinter as eggs or Iarvae in permanent systems, cmerge early after thaw, and females oviposit in water by mid-spring (Nowell, 1951). This seems ta he ret1ected in study pools where Dixidae larvae were collected during the middle of the spring season. Unfortunately, tittle is known abaut the life history of Erisralis, especially in temporary habitats. It is not known ifthe overwintering stage for Syrphidae is larvae dwelling in permanent waterbadies or adults; usually females oviposit in early spring in shallow water or in moist organic matter (Vockeroth & Thompson, 1987). This may explain why Eristalis spp. were found one week after thaw and were most abundant in the first week of May. • 37 • Coleoptera In 0 rder ta more clearly elucidate the seasonality 0 l'the beetles, adults and larvae have been considered separately. Dytiscidae (a) Adults The seasanality of Hydroporus spp. seemed sporadic (Fig. 34) because of the low numbers collected. They were found in ail poollocalities, l'rom the beginning of the season until the end of the fIrst wet period: none were collected al'ter drought. Two Laccophilus maculosus (Fig. 35) specimens were collected only in pools 51 and 52 in mid-May and in the beginning of June. • (b) Larvae Agabus spp. seemed to be the tirst dytiscid larvae ta appear and they were collected immediately after thaw in Morgan Arboretum pools (Fig. 36). Generally, they were present l'rom the second week of April till mid-May, and were collected after drought in pools M4 and S3. Colymbetes spp. larvae also seemed to appear early in the season and were present in pools W 1 and 54 from the second week of April till mid-May (Fig. 37). Unfortunately, there was no recognizable pattern of peak abundance for either species in any pool. The next dytiscid larvae ta be collected were Dytiscus spp., and these were found only in Senneville pools between the last week ofApril and the third week of May (Fig. 38). They tended ta be most abundant towards the end of their season and none were found after drought. The Acilius spp. larvae were among the last dytiscid larvae ta appear in most pools (Fig. 39). They were collected l'rom the frrst week of May till the frrst week of June: they • were most abundant towards the end of the frrst wet period ofeach pool and were collected 38 after drought only in pool M5. • Hygrotus spp. larvae appeared last (mid-May). but few specimens were collected (Fig. 40). This is aIso the case for Hydaticus sp., where only one larva was eolleeted during the last week of April (Fig. 41). Hydro philidae (a) Adults The seasonal distributions of Anacaena limbcua and He/op/zorus spp. were similar (Figs. 42 & 43)~ bath were eolleeted at the beginning of the season and were present until the ~nd of the tÙ'st wet period. They were also collected after drought, but were more abundant in the tirst wet period. Berosus striatus and Hydrobius spp. were found only in the tirst wet period (Figs. 44 & 45). Hydrochara obtusata was colleeted in pool 53 in mid-May (Fig. 46) and Cymbiodyta spp. were found in the second week of April and in mid-May (Fig. 47). • (a) Larvae The Helophorus spp. larvae were the only hydrophilids colleeted right aiter spring thaw (Fig. 48); they were colleeted in low numbers, and it is not known whether they oceur later in the season. Hydrobius spp. larvae were colleeted in the last week of April until the end of May (Fig. 49)~ in pool M4 they were found aise after drought. Hydrochara spp. larvae appeared in the flfSt week of May and seemed to he present until mid-May (Fig. 50). No peaks of abundance could he discemed for the hydrophilid larvae. Hydraenidae (a) Adults Hydraena spp. were present only for a few days immediately after spring thaw and • drought (Fig. 51). 39 The true seasonalities of adults and larvae of beetles collected may not he accurately • retlected in the tigures since few specimens were collected. AIso, since adults are capable of t1ight, theyare not necessarily restricted ta these pools. In contrast, the seasonalities of larvae can be examined more c1osely, since they are restricted to these pools for their growth and development. Although adult beetles are found at the beginning of the season and remain in the pools till drought, the seasonal occurrence of larval stages varies greatly among species correspond ta what was found in James' research. Little is known about the seasonalities of Hydrophilidae larvae in temporary pools. Helophorus spp. 1:lrvae and adults were collected immediately after spring thaw, whereas Hydrobius spp. and Hydrochara spp. larvae and adults were collected at the beginning of May. It would seem that larvae were found at the same time as adults; larvae were collected only mer adults arrived at the pools. • 40 • Hemiptera Ir is difficult ta determine the actual seasonalities of each taxon because few specimens were collected. Dasycorixa spp. and Callicorixa spp. were collected in pool Wl in late April (Figs. 52 & 53); Trichocorixa spp. were found in pool Wl on the last week of April and in pool Sion the fIrst week of May (Fig. 54); Gerris spp. were sporadically collected throughout the entire season (Figs. 83-92). It is doubtful that these figures accurately ret1ect their true seasonal distribution. For example, Gerridae were observed during the entire season on all pools, but were not collecred on every sampling date. The Hemiptera are nat necessarily restricted ta these pools, and are likely to be found whenever water is present. Trichoptera Limmephilus spp. were found in ail poollocalities and were collected from the frrst • week of April till mid-May (Fig. 55). !ronoquia spp. were found only in pool 53 and were present from the last week of April till the fIrst week of May (Fig. 56). Not much is known about the seasonal distribution of these two taxa in temporary pools other than the 1arvae leave these habitats by summer (Williams & Williams, 1975: Wiggins, 1996). Since adults oviposit in dry basins in late summer and in early autumn, it is not surprising that no specimens were collected after drought. AIso, since these eggs are present in the basins during thaw, they can potentially hatch once pools are replenished. This was evident in most pools where specimens were either collected immediately after thaw or within [Wo weeks of same. Odonata Odonates were collected in two pools, in pool Wl they were collected in late April, • and in pool SI they were found in mid-May (Figs. 83 & 89). Most Odonata utilizing 41 temporary habitats oviposit in plants or moist sail in dried basins during the summer and • autumn (Corbet, 1962~ Robert, 1962; Corbet, 1980). These eggs would have been present in the study pools at thaw, yet they do not appear ta hatch irnmediately. The appearance of Odonata later in the season appears to be correlated with high prey densities in the pools. Ephemeroptera Centroptilum spp. were col1ected in the frrst week ofMay and after drought (Fig. 91). The presence of tbis taxon is mostly likely accidentai, since it is not a usuai inhabitant of vernal pools (Edmunds et al.. 1976). Anostraca In most pools E. bundyi was collected immediately ufter thaw and was present until • the second week of May (Fig. 57); this organism reached peak abundance on different sampling dates in an pools. This species is known ta hatch promptly after spring thaw in early April and exhibit rapid growth for 12 days (Dabom, 1976). This was especiallyevident in pool W2. where the development of this organism was rapid enough to allow for the production ofegg sacs even though tbis pool remained wet for only 14 days! Generally. E. bUl1dyi tends to disappear once water temperatures reach the high teens (Pennak. 1978). Isopoda and Amphipoda Caecidota forbesi and Crangonyx minor have similar seasonalities in that they were collected throughout the entire season and were generally more abundant before drought (Figs. 58 & 88). These species are known to bury themseLves in mud or in the soil as ephemeral basins lose water (Pennak, 1978). • 42 • Gastropoda Aplexa elongata was found only in Senneville pools and specimens were collected 1-3 weeks from the beginning of t~e season till the end of the first wet period (Fig. 59); in pool S3 they were aIso round during the entire second wet period. Gyraulus spp. were collected throughout the season, whereas Stagnicola spp. were found only in the tÏrst wet pcriod (Figs. 60 & 61). Only one Lymnaea specimen was collected on the last week ofJuly (Fig. 62). These gastropods, with the exception ofA. elongata. are not restricted to vernal pools and can leave these habitats in search of another water source (Pennak. 1978). ln the study puaIs lhey were generally collected whenever water was present. Bivalvia Sphaerium occidentale was found during the entire sampling season in Senneville • poois and was more abundant in the frrst wet period (Fig. 63). This organism is known to exclusively utilize temporary ponds and pools. and can aestivate in the sediments of a dry basin (McKee & Mackie, L981: McKee & Madcie, 1983). The occurrence ofS. occidentale in the study pools could be due to the resumption of its activities once basins were replenished. Il is also known that arousal from aestivation is normally delayed as ta inhibit premature resumption of activity (McKee & Madcie, 1980); tbis could he why a lower number of individuals were collected after drought. Possibly many individuals were still aestivating after drought and if post-drought wet periods had been Longer. more bivalves would have resumed activity and been collected. Total nurnber of taxa per pool in relation to its hydroperiod The tota! number of taxa collected in each pool is presented in Fig. 82. The • hydroperiod of each pool was detennined as the total number of days that a basin was 43 inundated during the sampling season. • Pool M5 had the longest hydroperiod at 79 days, and pool W2 had the shortest with 14. Generally, the total number of taxa collected per pool increased with increasing hydroperiod. Pool W2 contained 9 taxa whereas 40 were collected in pool M5. With the exception ofHydrobaenus spp., not many taxa were exclusive ta pools with short hydroperiods; many of them could he round also in pools with longer hydroperiods (Table 1). In contrast, certain taxa were more common in pools with longer hydroperiods: e.g., Culex spp. (pools S3 and M5), Mochlonyx spp. (MS), Phaenopsectra spp. (M5), Eristalis spp. (S4), Crangonyxforbesi (MS) and Aplexa elongala (S3). This increase in taxonomic diversity with increasing hydroperiod or habitat duration is a weil known phenomenon in temporary habitats (McLachlan, 1981~ Collinson et al., 1995: Blaustein et al., 1996; Schneider & Frost, 1996; Williams, 1996). However, pool SI had a comparable number of taxa to that of pool M5 even though pool SI had a shorter hydroperiod. It would seem that geography and accessibility of pools to tlying insects and waterfowl ,ùso intluenced the number of taxa that would be collected. Senneville pools were • proximate to a permanent water source and more easily accessible to Coleoptera and waterfowl. the latter of which may have transported Anostraca and Bivalvia to these pools (Appendix 2). This pattern of taxonomie diversity seems to conform with MacArthur & Wilson's (1967) Island Biogeography Theories: (i) an area more isolated will receive less immigrants than an area close ta the source area, and (ü) there is an increase in number of species with inereasing island size. If each study pool is viewed as an "island", then pools doser to a "source area", such as a permanent water source, will receive more taxa. AIso, pools with longer hydroperiods were originally larger "islands" at the beginning ofthe season and therefore should be colonized by more taxa. This nüght suggest why a greater number of taxa were collected in Senneville pools and in pools with longer hydroperiods. However. Island BiogeographyTheories do not take into account the changing nature of temporary habitats. These "islandstl change size with time and quickly disappear. This temporal component is a major factor which will determine the number of taxa found in • ephemeral pools (Williams, 1996). 44 Price's (1984) Time Paradism Model and Schneider and Frost's (1996) Life History • Model have shown a relationship between habitat duration and the time required for taxa to \.:omplete their aquatic life stages. They observed that life histories will determine which taxa are capable of surviving and reproducing in a pond of a particular duration (Schneider & Frost, 1996). Therefore, a larger number of taxa with variable life histories should he found in longer lived habitats. Even though Senneville pools were close to a permanent water source, the lite histories of these animals will determine whether or not they can utilize the habitats. This is especially evident for the Wildlife Area pools since they were also near a permanent water body and were casily accessible to tlying insects and waterfowl, but tew taxa were collected. Perhaps their hydroperiods may have been tao short for the development of many organisms collected in this study. Organisms which appeared late in the season, such as Culex, Anophe!es, Chaoborus and severa! of the Coleoptera, could not use the WildIife Area pools: these habitats were dry at the time when these taxa would normally exploit the pools. In conclusion, the locaùon and accessibility of pools will play a role on how readily they were • colonized by organisms, but il is the hydroperiod that will determine whether or not taxa cao reside in a .specitic habitat. Summary of successional patterns observed in study pools Figs. 83-92 summarize the seasonalities observed for the major taxonomie groups collected in each pool. The most probable scenario to explain the seasonal and sllccessional patterns observed for these organisms is as follows: As temperatures increase in the spring, vernal pools are replenished by snow melt and rams. While the water is warming, microorganisms are aetivated and start ta degrade detritus found within the basin. Soon afterwards phytoplankton and zooplankton tlourish in the pools ('.~lilliams, 1996). The wetting of the basins coupled with tht ùt:l:rease ofdissolved oxygen in the water • (microbial activity) triggers the hatch of severa! taxa, namely Chironomidae, Culicidae 45 (Aedes) , Tipulidae, Eubranchipoda and Trichoptera(Pennak, 1978~ Wood eta!., 1979~ Oliver • & Roussel, 1983: Wiggins, 1996). Arnphipoda, Bivalvia, Gastropoda and Isopoda resume activity once water has retumed (Pennak, 1978; McKee & Madcie, 1981). Ali of these organisms can utilize the resources that are immediately found within the basins: they are either tïlter-feeders, consuming bacteria and plankton, or detritivores, feeding on decaying plant and animal matter (Pennak, 1978: Wood eta/., 1979: McKee & Madcie, 1981: Oliver & Roussel, 1983: Wiggins, 1996). A few days laler, Moch/onyx spp., hatch and feed on zooplankton and early instar rnosquitoes (Saether, 1970). Therefore, the lirst organisms to be found in the pools are thase that have overwintered in the basins as eggs or as aestivating adults and juveniles. In the meantime, permanent water systems are slowly thawing and organisms such as Coleoptera and Hemiptera, which had overwintered in these habitats, disperse into vernal pools. Adult Dytiscidae and Hemiptera teed on a variety of prey items whereas, Hydrophilidae and Hydraenidae consume plant and animal maner found around or within the pools. They saon oviposit, and juveniles appear about one week later and feed on • zooplankton, culicids and other immature insects (Young, 1954; Nilsson & Soderstrom, 1988: Smetana, 1988; Larson & Roughley, 1991). Adult tèmales ofDixidae and Syrphidae Iay eggs in the pools in spring and larvae appear in mid-spring feeding on microorganisms and detritus (Peters, 1981: Vockeroth & Thompson, 1987). Culex and Anopheles species whieh had also overwintered as adults, oviposit in the paols in spring and early summer. Larvae soon appear, consuming detritus and bacteria found in the pools (Wood et al., 1979). Chaoborus larvae are amangst the last Diptera ta appear, since females oviposit ooly in late spring. These 1arvae are also predaceous, and feed on early instar culicids and zoaplankton (Saether, 1970). One of the last organisms to hatch in the pools are Odonata! and nymphs consume any prey item ofappropriate size (WaIker & Corbet, 1975). On the whole, the rmal taxa to appear are thase which oviposit in vernal pools after thaw or hatch late in the season. In fael, many of them are predaceous, and usually appear when prey populations are at their highesl. • As water temperature increases, development ofthese invenebrates occurs at a l'aster 46 rate and certain taxa begin to vanish from the pools. One ofthe first taxa to disappear is the • Eubranchipoda: eggs are produced before death and these faU to the bottom of the basin (Pennak. 1978). Soon afterwards, most Diptera pupate and emerge. Trichoptera then emerge followed by Ch aoborus. Culex and Anopheles. The last insects to emerge from the pools are the predaceous Coleoptera and Odonata. The last animaIs to vacate are some of the gastropods which leave in search of moist habitats. The remaining taxa do not actually leave the drying pools but aestivate in the basins. Amphipoda, Isopoda and Bivalvia burrow in the mud and sediments of the basins (Pennak. 1978: McKee & Mackie, 1981). Sorne Gastropoda. such as Ap/e:ca elongata. seaI their operculum and hide under plant liner (Clarke. 1981: Brown 1982). These organisms wait for the arrivaI of new water, and after drought can quickly resume activities. Few taxa were found in pools after drought. Multivo1tine chironomids and culicids appear at this time (Wood et al., 1979: Tokeshi. 1995). Adult Co1eoptera and Hemiptera retum to these systems ta feed and ovipasit. Generally, mOSl Diptera can complete development befare pools dry out agaïn, but this is nct necessarily the case for immatures of • Coleaptera and Hemiptera. • 47 • Conclusions 68 macroinvertebrate taxa were collected from ten temporary snowmelt pools in southwestern Quebec. Amphipoda, Anostraca, Bivalvia, Diptera, Coleoptera, Ephemeroptera, Gastropoda, Hemiptera, Isopoda, Odonata and Trichoptera were collected. AlI taxa collected have been previously recorded in Quebec or in eastern North America: pools in the same geographic region tended to have similar taxa. Habitat characteristics and proximity of pools to a permanent water source appeared ta influence the abundance and distribution of taxa. The hydroperiod of pools coupled with the presence of shade and the species of tree surrounding the pools influenced the occurrence and abundance of culicid species. Chaoboridae were found more numerous in pools that were surrounded by truck vegetation. The only genera of chironomids that were collected in abundance were thase which have been previously recorded in vernal pools. Syrphids were collected mainly in one pool where decaying matter was plentiful. Dixidae and Tipulidae were found in low numbers since they are not usuaIly found in vernal pools. Most Coleoptera were found in • Senneville pools and this may he due ta the praximity of the pools to a permanent water body. Few Hemiptera were collected, but were generaIly found in aIl pool localities. Trichoptera and Odonata were generally found in pools with longer hydroperiods. In contrast. the ephemeropterans found in one pool do not usually inhabit temporary habitats. Only one Anostraca and one Bivalvia species was collected: the accessibility of Wildlife Area and Senneville pools to waterfowl could explain the distribution ofboth taxa. The eggs of Isopoda and Amphipoda are often dispersed by wind; tbis may explain the wide distribution of Isopoda but not why that the Amphipoda was found ouIy in one pool. Gastropoda collected were all capable of utilizing temporary habitats and were not necessarily restricted to such pools. The seasonalities of the various taxa was determined. The seasonality of culicids is int1uenced by the timing of oviposition and egg hatching ofeach genus/species. Aedes eggs overwinter in basins and can hatch in early spring. In contrast, adults of Culex and Anopheles are the overwintering stage, and eggs are laid in the pools in lale spring; Culex and 48 Anopheles larvae appeared later than Aedes larvae. Each species of Aedes exhibited a • distinct seasanal distribution due to the differences in their timing ofhatch. A similar pattern was seen for the Chaoboridae: Mochlonyx larvae appeared early in the season since eggs are the averwintering stage; Chaoborlls larvae were found a few weeks later because adults emerge l'rom permanent waterbodies in late spring ta then mate and oviposit. The seasanalities of chironomid taxa appeared to he determined by their ability to develop at law temperatures. Chironomids of the subfamily Orthocladünae are capable of rapid development at low temperatures and were amongst the tïrst to hatch and be callected in the study pools. The remaining chironomids were essentially thermophilius: they were llsuully collected, or were more abundant, later in the season as water temperatures increased. Tipulidae larvae were l'ound immediately after thaw since overwintering eggs hatched once pools were replenished. ln contrast, Dixidae and Syrphidae females oviposited in the pools in spring and larvac were collected a few weeks aiter thaw. Hemiptera and adult Coleoptera were found during the entire season but the seasonality of beetle larvae varied among genera. Generally, larvae were present only after • adults migrated ta the vernal pools. Trichaptera appeared immediately after thaw because eggs are laid the previaus autumn and can hatch quickly once they are inundated. In contrast. Odanata averwintering eggs hatched only in late spring ta coincide with the occurrence of high prey densities. Anostraca appeared immediately after thaw since overwintering eggs hatch once pools are replenished. They were collected only until mid-spring when water temperatures reached the high teens. Isopoda and Amphipoda were collected throughout the entire season since these organisms bury themselves during drought and can quickly resume activities once water retums. Gastropods and bivalves were generally found whenever water was present, since these taxa can either disperse or aestivate during unfavourable conditions: they return or resume activities when pools are replenished. An increase in taxa diversity was observed with increasing pool hydroperiod. However, the location of these pools and their proximity to a permanent water saurct: also • influenced the number of taxa that would be collected. The location and accessibility of 49 pools to flying insects and waterfowl seemed to play a role on how readily they were • colonized by organisms but it is the hydroperiod that determined whether a taxon could reside in a pool. A successianal pattern was observed in ail paols. The frrst arganisms ta be found were those that overwintered in the basins as eggs or as aestivating adults and juveniles. These organisms were fùter-tèeders or detritivares and could utilize resources found within the newly formed pools. They were followed by predaceous taxa which most likely tèd upon them. As the season progressed anostracans produced eggs which feil to the battom ofthe basin and early appearing insects emerged. Predaceous insect taxa were the last ta emerge and sorne gastropods left before drought. Sorne taxa such as Amphipoda9 Isopoda9 Bivalvia and one specics of Gastropoda remained in the drying basin and aestivated awaiting for the drol1ght~ arrivai of new water. Few taxa were round in pools after only multivoltine 9 summer taxa and animais which aestivated in the basin, appeared at this time. • • so Table 1: Total Number of Specimens Collected per Taxon in Pools in Southwestern Quebec (Pools arranged in increasing hydroperiod) • Taxon 1Pool W2 W1 M3 M2 M4 82 81 S4 83 MS Total Arthropoda Insecta Diptera Culicidae Aedes canadensis 278 1n 318 1 29 804 Aedes cinereus 41 16 1 458 516 Aedes communis 51 66 191 211 1 11 7 1 539 Aedes diantaeus 33 48 110 26 217 Aedes euedes 3 20 63 14 368 468 Aedes excrucians 1 2 111 165 355 1 14 1 190 839 Aedes intrudens 1 7 2 10 Aedes provocans 11 2 11 38 44 153 72 440 772 Aedes punctor 133 67 44 2 246 Aedes stimulans 42 1 5 607 861 821 5 906 3248 Aedes vexans 77 43 117 69 115 45 38 504 Aedes species· 5 655 3n 1086 76 187 523 5 1123 4037 Culex pipiens 1 13 401 4 419 Culex restuans 15 906 245 1166 • Culex territans 4 2 6 Culex species· 282 282 Anopheles quadrimaculatus 1 14 15 Culicinae pupae 28 130 142 372 340 1257 231 97 1719 4316 Culicidae Total 18404 Chaoboridae Chaoborus americanus 1 30 1 25 12 69 Chaoborus fJav;cans 1 8 1 10 Moch/onyx cincipteslvelutinus 28 48 85 13 18 24 9 408 633 Chaoboridae Total 712 • ·Indicates early instars that were tao small te be identified 51 Table 1 (cont'):Total Number of Specimens Collected per Taxon in Pools in 50uthwestern Quebec (Pools arranged ln increaslng hydroperiod) Taxon 1Pool W2 W1 M3 M2 M4 52 S1 S4 S3 MS Total Diptera Chironomidae Chironomus spp. 6 42 95 171 60 374 Corynoneura spp. 4 8 3 2 17 Ooithrix spp. 18 16 14 7 55 Eukiefferiel/a spp. 2 2 Harnischia Spa 1 1 Hydrobaenus spp. 38 1100 6 1 1145 Larsia spp. 1 1 Limnophyes spp. 19 3 3 11 53 8 44 142 Phaenopsectra spp. 7 1 4 1119 1131 Polypedilum Spa 1 1 Psectrotanypus spp. 5 6 Pseudochironomus spp. 2 2 Smittia spp. 12 12 Zavrelimyia spp. 1 2 3 Chironomidae total 2892 Dixidae Oixella spp. 1 3 1 4 9 Syrphidae Eristalis spp. 6 2 1 2 163 9 6 189 Tipulidae 1 1 1 1 2 1 7 52 Table 1 (cont'):Total Number of Specimens Collected per Taxon in Pools in Southwestern Quebec (Pools arranged in increasing hydrbperiod) • Taxon 1Pool W2 W1 M3 M2 M4 52 81 54 53 MS Total Coleoptera Dytiscidae Acilius spp. (Iarvae) 3 48 23 26 16 19 135 Agabus spp. (Iarvae) 5 6 7 4 2 4 1 2 31 Colymbetes spp. (Iarvae) 5 8 13 Dytiscus spp. (Iarvae) 2 11 14 Hydaticus sp. (Iarva) 1 Hygrotus spp. (Iarvae) 2 2 Hydroporus spp. (adult) 2 9 1 6 6 3 2 5 7 39 Laccophilus maculosus (adult) 1 2 Hydraenidae Hydraena spp. (adult) 3 42 15 60 Hydrophilidae • Helophorus spp. (Iarvae) 2 3 3 9 Heloph0 rus spp. (adult) 2 1 2 3 3 3 1 13 Hydrobius spp. (Iarvae) 6 22 4 3 37 Hydrobius fuscipes (adult) 1 2 1 4 Hydrochara spp. (Iarvae) 1 2 7 10 Hydrochara obtusata (adult) 2 2 Anacaena limbata (adult) 1 3 14 4 36 7 64 Berosus striatus (adult) 1 3 1 6 Cymbiodyta spp. (adult) 2 3 • Coleoptera total 445 53 Table 1 (contl):Total Number of Specimens Collected per Taxon in Pools in Southwestern Quebec (Pools arranged in increasing hydroperiod) • Taxon 1Pool W2 W1 M3 M2 M4 52 51 54 53 MS Total Hemiptera Corixidae Callicorixa sp. 1 1 Dasycorixa sp. 1 1 Trichocorixa spp. 1 5 6 Gerridae Gerris spp. 2 1 3 6 13 Trichogtera Ironoquia spp. 6 6 Limnephilus spp. 2 81 3 14 9 109 Odonata Sympetrum obtrusum 15 15 Anisoptera (larvae) 2 2 Zygoptera (Iarvae) 3 3 • Ephemeroptera Centroptilum spp. 4 4 Eubranchipoda Anostraca Eubranchipus bundyi 234 52 672 156 86 966 Malacostraca Isopoda Caecidota 'orbesi 8 44 9 238 2 427 728 Amphipoda Crangonyx minor 118 118 • 54 Table 1 (cont'):Total Number of Specimens Collected per Taxon in Pools in Southwestern Quebec (Pools arranged in increasing hydroperiod) Taxon 1Pool W2 W1 M3 M2 M4 82 81 S4 S3 MS Total Mollusca Gastropoda Aplexa elongata 5 63 138 206 Gyraulus spp. 25 7 51 2 1 2 63 Lymnea sp. 1 1 Stagnicola spp. 13 9 22 Bivalvia Sphaerium occidentale 125 419 1073 284 1901 Mollusca total 2193 5S • Fig. 1: Seasonality of Aedes provocans in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum Pool #2 c t .A ••••••••• A ••••••• Pool #3 CCC.A ••••••••••••• + • • • •• • • • Pool #4 ...... A •••••••••• · . Pool #S ...... A ...... Senneville Pool #1 "" A A A A .. .. Pool #2 • • •• • • • · . t • .. A • • .. .• • • • • • ••••••• Pool#3", '" _. • A .. A. Pool#4 cc •• • • • •• • • • • • . .. • • ·... • .. ... · '" . Wùdlife Ana .., Pool #l.~C~C~=====~';'';'':'':,,=,-=-,:,:~~~~• •• • ••• • •• • • ·-TnTTTTT•••••••• ~ ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ ~ ~ ~ ~ ~ " M ~ =• ~ " • • " ~ c " • " ~ ~ " ~ ft ~ ~ ~ " " " ~ ~ ~ Sa=p!1nq Dates Fig. 2: Seasonality of Aedes communis in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum .., • ace . * . Pooli2 oP Pool #3 A ••••••• '" cccccc ...., ---_...... Pool #4 •• • • • • • • · . Senneville ... Pool#1 CCC C • A ._. * • * ••••• · . Pool #2 c cac cc. A • " • .. A *•••••• • * •••••• Pool#3 ... '" A . * .. * .. A .... • ••• A ••• Pool#4 ccc ccc .. • .. • A A • A • * * . Wildlife Ana t Pool #1.~===.====~.~.=-:.~.~.:.:.~.~.:..:..:.~.~.~ ·-TnTTTTT•••••••• • 2 Present C =uncert&n about speeiesl presence (emy larval mges .genmidentification only) A =Wet;NotConected e=Dty Note: Sampling dates befote 2314 cliffer among pools ~ =Peak abundance Morgan A%boretum : 1314, 15/4, 19/4 Note: absence of symbolfor apoolindicl1es Senneville: 914, 1314, 1614, 2114 • equalnumbers conected during semp1ingperiod W'dd1ife Area: 1214, 1514, 1914 56 • Fig. 3: Seasonality of Aedes stimulans in various pools (Southwestern Quebec) : April- July 1998 Morgan .Arboretum Pool #3 ccc ccc c _ • .. .. ••• .. .. • • • • .. .. A _ __. Pool #4 ccc CC_ .. _.. .. ••• • • •• Pool #5 CCC" ...... • • • • A""""."" Senne\~e • Pool#l CCC C • ...... A ... • • • • ...... _ ..... Pool #2 CCC c t._.. _. •• • • • .. * •••••• Pool #3 .. .. • .. •••iii A...... A .... • .. .. • ""A""" •• Pool #4 ccc c tA.A • .. .. e .. . .""e" ••• Wùd1ife Area .. e • Pool #1.~======~.:,:.~.:,:.:,:.:,:.~.~~~~:,•• ·-TTTTTTTT••• ••••• • SUlJll1n~ D.~es Fig. 4: Seasonality of Aedes intrudens in various pools (Southwestern Quebec) : April - July 1998 Morgan Arboretum Pool#-2 cecce .. . •• A • .. ••• Pool #4 cco_•••••••••••• ...... Pool #5 cccoac_ * .. AAAAA""A ·-TTTlTrTT ...... ,.,.,.,.,.,.,.,101D """"""""""C'lC\ft'l,"~CI'I."poo=.poo"'''II'''''.'''. 9'49'49'4 ...... "c.C"Ct'l ...... "ftft Sapl1n; D.~es • =Pre~en1 C =uncertS ~bout ~ecier presence (e my lun!stage: •genen ident.iiication amy) * = ~let; NotConected e=Dry Note: SampImg da1e:: before 2314 diiÏer among pools -+- = Pe:!k 3.bu:l~ce MorgmAtboretum.: 13/4, 15/4, 19f4 Nou: ab::ence of symbol for t pool indicues Seœe'?iJle :Ç!4, 1314, 1614, 2114 • equal numbe::; collected du:ing samp1it1g pe:iod WildJife Ares: 1214, 15/4, 1914 57 • Fig. 5: Seasonality of Aedes punctor in various pools (Southwestern Quebec) : _.\prïl- July 1998 Morgan .Arboretum .... :;'001#2 ccc .. * • lit • • ••••• P.:lol#3 ccc ... * lit lit • • ••••• Pool #4 cc c_*_ * * * • • ••••• Pool #5 cc c_* * 1\ lit lit • * • *•* • ~~~~~~~~~~~~~~~~~~~~ ~ ~ ~~ ~:=~~~.ro-::: ~=::~ .... Samp li:; Da~~s Fig. 6: Seasonality of Aedes euedes in various pools • (Southwestern Quebec:) : April- July 1998 Morgan Arboretum Pool#2 * • *••••• Pool #5 •• *.**** S=:':Ùle Pool #1 ccc c.- ** ••••••• .. • * • * ••• Pool #2 ccc c •• lit *••••••• .* •••••• ? 001 #4 ccc C· * • • • *. •• • --TrrrmT** •••••• """" In ln ln ln 1") ln" ln \0 \0 """"""""""~~~II")\O~·~~=.~" ool ... 9't ...... C'tC'tl"i ...... •••C"I "c"... C"I !uçl1:q D.~e: • ·Pr!~ent C • unce:t= ~bout =;pecie:l pesence (emy lamlstqes •ge:en idtmincùion am" A =Wet; Not Conec+~d e=Dry Not.e:S3:Çq cl6t.es before 2314 differ amang pools ~ =Peûabu:lci=lce M~A:èoretum: 1314, 1~/4, 1914 Note: tb=ence ofsymbol for apool inclicues S~?il1e :914, 13/4, 1614, 2114 • equ&number: collected liuring samp1ù1gpe:icd wadiie A:e~ 1214, 15/4, 19!4 58 Fig. 7: Seasonality of Aedesexcruciansin various pools (Southwestern Quebec) : April - July 1998 Morgan Arboretum .. Pool #2 ccc • • •• • • •• • • • • •• • • Pool #3 CCC t • • • • • • •• • * • • •• • • Pool #4 ccc t • • • •• • •• • * .. .•• • • Pool#S ccc t ...... A • " . ..• A .... Senneville " " Pool#1 CCC c t ._._. ... • • • • • .. " " A ••• Pool #2 0 CCC. A • A A A • •• .. A • . • A " A ._ • • • • • • •••• Pool#3 1\ ...... A • • • • A .. .. .• • • • • • • W~dlife Area •••• Pool #1 ft • * * • *_. • • • •• • • • • • • • •• • • • •• Pool #2 .. " * ••••• • • • •• •• • • • • --TTTnTTT•••••••• Fig. 8: Seasonality of Aedes diantaeus in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum Pool #2 ccc .. + •••••• • • • • • • • • •• Pool#3 CCC * •••••• • • • • • •• •• •• Pool #4 ccc t • " .. • Pool #5 + •••••• • • • • • • CCC *_A A*A ••• A .. * A * • --TTTnTTT• A .. " Samp lil1tJ Dates • = Present C = uncert&n about species' presence (early larra! stages -genen identüication on1y) *= ~let; NotConeeted e=Dty Note: Sampting dates befote 2314 difFer among pools ... = ~_-boretum Pe3k abundenc! Morgm : 13/4, 15/4t 19/4 l Note: abs ence of symbol for pool indicaus Senneville: 9/4t 13/4, 1614, 2114 equ&numbers coUected duringsamp1ingpenod Wild1ife Area: 1214. 15/4t 1914 59 Fig. 9: Seasonality of Aedes canadensis in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum .. Pool #2 oocee .. •• • •• • • e_·· ... Pool #3 cccee •• • •• • • a-·...... ·. Pool #4 CCC .... • •• •• C_...... Pool #5 ceceaa ...... • '* .. c ..... '* Sennevi.11e • '* _ ...... Pool #3" .. lit .. " .. ..'* .. '* ...... '* • .. lit '* '* .. Pool #4" .. lit ...... _ '* '* • • .. • '* • .. • •• • ...... ·-TrrTTTTT Fig. 10: Seasonality of Aedes cinereus in various pools • (Southwestern Quebec) : April- July 1998 Morgan Arboretum ... Pool #2 ...... • • • '* .. .. • • • • • • • • a_ . Pool #4 .. • • • • • .. • • • .. • • • • • • • a . Pool #5 .. ... • • • .. '* .. • • .. .. · .. • .. • c'" .. Senneville Pool #4 ...... • " .... '* * ...... " .. ·... ·-TrrTTTTT ~ f'" f'" f'" f'" f'" fi- f'" G\ N ~ G\ t"l ~ cs t"l """"N ...... CIl N Samp11ng Dates • = Present C = uncert8in about species' presence (early larval mges .. genm idemmcation only) :Je =Wet; Not CoUected • =Dry NQ•• ~: SAmpling dates before 2314 diffet among pools ~ =Peak abuncl8nce Morgan Arboretum: 13/4, 1514, 19/4 Note: absence of symbolfor, poolindicates Senneville: 914, 1314, 16/4, 21/4 • equal numbers conected during sampling penoe! Wild1ife Area: 1214,1514, 19/4 60 Fig. Il: Seasonality of Aedes vexans in various pools (Southwestern Quebec): April - July 1998 Morgan Arboretum Pool #2 A A. a ...... " " A • •••• • " "A "• " " " • • • Pool #3 • • A A A • • Il. • •••• • a_•• • Pool #4 " • • .." • " A • " • • ••• • a ..... " • • • Pool #5 " " . a_.A• A A " " " ·" ." " " • " " " " " " " Sen:leviI1e . . · ... Pool #1 a_••• " " " • • • " " " A " A • • • • • •• • • • Pool #2 .." " .• " " • A " • • A • • • • • • c ••••• • • Pool #4 ••• " " • • a_" ••• • .·." ." " " " . ·" • ·-tnTTTTT• • • • • • • ~ • • • ft ft ft ft ft ft ft ft ~ ~ """"""""""~ N ~ ft ~ ~ " ~ ~ =• ~ • •• • ft =• • " " • • • ft ft ft ~ • • • ft ft ft Samp11n; Dat.es Fig. 12: Seasonality of Culexpipiens in various pools (Southwestern Quebec): April- July 1998 Morgan Arboretum Pool #5 A • • • " " ." " " A A " " " " " " .." " . Senne\iIle ". " Pool#1 " " " " • • " .." A " " " •.. • •• ." "... • A ••• Pool#3 " " ." " CCI • " " A ._. ._. . •• " " " " A ••_A _.. ••• Pool#4 " " " ..- " • * • •• . " ." " . ·-tnTTTTT SUlll11D9 Dat.es • =Pre~ent C =uncerWn. ~bout =pecie~ pte:;ene~ (emy la.."V~ mge:-g!nettic!e:U.üication onl1) *=Wet; NotCoUec+.ed e=Dry Note:Smt;l~ date: before 23/4 difÏe: mongpoc1= ~ :: ?e~ ~bu:lci::lce MomnA.-boretum: 13/4, 15{~ 1914 Note: ab:;ence of symbo1 for ! pOQl:ndic~s S~!"riIl! :914.1314, 16/4, 2114 e~numoe."': collectee! du::ng umpJingpe:iod Wild1iÏe Area: 1214.l.S/4, 1914 61 Fig. 13: Seasonality of Culex restuans in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum Pool #2 1\ 1\ 1\ • * ft * * * * .. * •• •• • •• cc-._... Pool #5 1\ 1\ 1\ .. 1\ Il Il .. Il Il cc • • ft * * * .. • * • Senneville "- Pool#3 * 1\ ft 1\ 1\ 1\ 1\ 1\ • • Il ca •• * * • * • * • • * --,.,.,.,.,.,.,-r Fig. 14: Seasonality of Culexterritans in various pools (Southwestern Quebec) : April- July 1998 Mor~ Arbo~te:n Pool #5 * • 1\ * Il * 1\ ft .. * * * 1\ A 1\ • * A .. * A • .. A_. S=:\"Ùl: .- Pool #3 Il A A Il .. A A 1\ A A CC ...... * * 1\ .. .. •• • * * --TTTTlTTT • =?re~ent [:J :: unce:um ~bout =P!:i!~ pte!:!:::! (eciyle.~~~!:-g=eniddScation cm!') "= :: Wet; NotConec+~d e=Dry Not!:Sœp~ c1!1!: before nf4 c!iffer am~po~ ~ =?e~ 3.bt::l~c: Li~=A:bor:tu:L: 1314. l~l4. 19/4 Note: ab~ence of Sj':1co1for t pool:nc!ie~$ S~!~! : 914, 1314. 16.14, 2114 • eqWoumb::: conec:tec! êt--g ==plingpe:icd Wik$ie }.re~ 1214. lj/4, 1914 62 • Fig. 15: Seasonality of Anopheles quadrimaculatus in various pools (Southwestern Quebec): April- July 1998 :~::za:: _':;_~Q:'~= Pool #5 li! * * * • li! li! * * * * *** * • * • * * .. • • • •• S=:viIle Pool#4 * * * * * * * • * .. .. * .. * • • • • • * •• • • • •• • --TTTTTTrr Fig. 16: Seasonality of Mochlonyx spp.in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum .... Pool #2 .. • ...... • •• • • * • * • • Pool #3 • * • t ..... ••••• • • * ••• • • • Pool #4 * • ... •• ••••• • • • • • • Pool #5 ... .. • • • * ...... * • Se=:vi11e li! • Pool#1 • ._..- • • • • • • • • • .. .• • •• • • Pool #2 • .. .. * * • • t • • • ••• • •• • ••••• Pool #3 * ...... *-* ..... t .. •• • * . .•• PooL #4 _. .. .. ·.. .• ...... • ••••• --TTTTTTrr ~ ••••••••• ~~nn~~nn~~ """"""""""~~~~~~.~~=.~·.D.nc ..... "~~~ ~ .. ~~~ •• Scp11:q Dace • a Present C a unce:Uiil ~bout ~ecie~ presence (edylarnl stage:: -ge:;mide:Wiic:ation onl:;) *:: Wet; N"tCoUec:+.ed e=Dry Nole: SampqdUe: belote !3l4 diffe: amongpools ~ :: Pe3k ~bc:l~c: M~.~.:boretum: 1314, 1~/4, 1914 Note: absence of symbol for lpoolindicùes Se:me'rille :914, 1314, 1614, 2114 • eqœ1 numbe:: collected duë1g nmpling pe::iacl Wild!iie Ana: 1214, 15/4, 19/4 63 • Fig. 17: Seasonality of Chaoborus americanus in various pools (Southwestern Quebec): April- July 1998 Morgan .A.rboretum ... Pool #5 " • " • il • " • .. " • • " " • " _. SeDn~viIle -- ·. .. .- . Pool #1 * •• • • " ..._.•..... " ••• Pool #2 " ·. " _ "" " . * " " * • • " * ..._...... • • • •••• • Pool #3 • ·" " " " • " " " •. *._. " *" .. * • • • Pool #4 * • • • ••• ·" " • ** *. *"*.--. " "** •* ...... ,.,.,.,., .,,,., 10 \Cl """"""""""='INl"'lll'l~G'I"'r"l"'="~."CD."'="'''' ...... N:'CC'IIr"l ..... C'IIc.e-t S~11nq na:.es • Fig. 18: Seasonality of Chaoborus f1avicans in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum Pool #5 " " * " il • " ." • * • • • .." • • * • Se~:ville .-.- " _ Pool #1 " " • • il il • • • ._* ...... " • .. ••• " " il • . Pool#3 " *** • • *_.*- *** .. ••• " " *** * --TTTTnTr" • = Present * =Wet; NotCoUected .:D%y N~: Sempling dates before 23/4 differ amang pools ~ =Peak abunduu:e MorgmAfbotetum: 1314, 15/4, 19/4 Note: absence ofcymbolfortpoolindicms Senneville: 914, 13/4, 1614, 2114 • equal numbers collected during sampling pe:iod Wlld1ife Area: 1214, 15/4, 1914 64 Fig. 19: Seasonality of Limnophyes spp. in various pools (Southwestern Quebec): _~pril- July 1998 Morg~ Mor~tum ~ Pool #2 A. A A ._A A A * A •• • • •• • .. A * • .. .• • Pool #3 - A * A A .. A .... • • •• • .. .. A • • • • • Pooi#4 .. A •• A A .. A_A .... • • •• • ...... • • • Pool #5 _A A A A A A .. A A A A .. A • A A .. .. A ·A A .. A A Senneville ?oc; #i • *' ft *' ft •• • • • • '* *' ft • Il • • • * _-.. ft .. Pool#2 A .. A A A A A ft A ".. •• •• * * •• • • • • Poo!#3 * _. • A A A A ... A A A A ... A A A A A A A A A A • • • ?ool#4 " "_A A A A ... A A .. A A • A • •• .. A A • ... --TnTTTTT• • • •• • Fig. 20: Seasonality of Doithrix spp. in various pools (Southwestern Quebec) : _~pril- July 1998 Morgan .Arboretum ~ Pool #2 A • A •• A A A .... • ••••• • •• • • Pool #3 A .. A A A ••• A _. •••• • •••• •• ... *- . A A • Pool #4 ...... • ...... ••••• .. .. • •• Pool #5 A _A .. A ...... * .. A .. .. • • Present. *= Wet~ NCt. CoUected e=Dry Nole: Samplmg dates befOte 2314 ctiffer among pools ~ = Peak ab~dmlce MorgmArbOfetum: 1314.15/4.19/4 Note: absence of symb 01 for l pool inclicates Senneville: 914. 131~ 1614, 21/4 • equ& n\lmbers colleeted during sampling penod WùdJife Area: 1214, 1514. 19/4 65 Fig. 21: Seasonality of Hydrobaenusspp.in various pools (Southwestern Quebec) : April- July 1998 • Morgan Arboretum Pool #4 *_. • • • • • • • • • • • •• • • • ••• A ••• Pool #5 • • • • • • ••• ••• 1\ • •• * * A.*.A** • wild1ife .Ana • Pool#1 ... • • ••• • • •• • • • ••••••• .~=====.:.:..:.:..:..:..:..:...:..:..:..:..:.• • • • • • •• ••• • • • ••••••• Pool #2 • - -,.".,..,-rrr S1ImP11~ D.te~ Fig. 22: Seasonality of Chironomus spp. in various pools (Southwestern Quebec) : _.\.pril- July 1998 l~orgcm .Arboretum ... Pool #5 • • • A 1\ •••• AA •• S::meviIle -----_._-- Pool#1 ___ 1\ 1\ ft•• A • • • • •••• • A •••••• Pool #2 * • 1\ 1\ _ ••• A . ___1\ •••••••iii... ••• Pool #3 ft ft - ••••••••A ••••••••.. Pool #4 • ft 1\ 1\ •• 1\. lit •••lIIIIiiil*_.* • A A •• * ••• ., ., ., • • • • • • • " " " ., ., ., " " la la """"""""""C71NC"lll"l 100\.'" fOo= ., . • ...... • • f'C fi( C\t t'"I (Iil f'C (Iil Smp11nq Dates Fig. 23: Seasonality of Phaenopsectra spp. in various pools (Southwestern Quebec): April- July 1998 Morgan Arboretum .. Pool #2 ft A * •• 1\ _ ••••••••••• •_ •• * ••• Pool #4 AA .A.A •••••••••••• *_iA... 1\ • A •••A Pool#5 ••••••••• AA •• A. Sen:leville Pool #1 A • 1\ A A A A A 1\ • A •• A •••••• * 1\ * ._••• •- ,.".,..,-rrr .,., •••••••• ""11'\"., .,"'., la lA """"""""""C71N C"lll"lIOC7I .. lO\fOo=.I' = .. .,0 •• • ...... C"l C'f lN C"l C"l f'C f'C Samp 11nq tl.tes • -Present *=Wet; NotCoUected e=Dty Note: Sampling dates before 2314 dift'er among pools "" = Peu abuncbnce MarganA%boretum: 1314, 15/4, 19/4 Note: absence of symbolfor a. pooLindicates S~evme:W~131~1~~2L~ • equti numbers conected du:ing sampJingperiod Wlldlife Arel: 1214. 1514. 1914 66 Fig. 24: Seasonality of Corynoneura spp. in varions pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum .. Pool #2 ...... AA." ••• Pool #4 ...... _A . A .. _ ••••• Senneville Pool #1 A A • • • • .. .. • • • .. .. _. ••••• .. _.- .... • __ ••• AA Pool #3 A • • • A .. .. A • • A ...... A A A A. A --TTmTTT Fig. 25: Seasonality of Eukiefferiel/aspp. in various pools (Southwestern Qucbec) : April- July 1998 Wùdlife .Arca Pool #2 _... A • •••••••••••••• •••••••• • --TTmTTT Fig.26: Seasonality of Psectrotanypusspp.În various pools (Southwestern Quebec) : April- July 1998 Senneville Pool #1 .. • A A • .. A A A • A A A .. _. •••• • AA ••••• Pool #3 • • A .. A A • A • A • .. A A A A .. A • A •• A ...... --TTmTTT ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ ~ ~ ~ ~ ~ ~ ~ ~ =• ~ " • • ~ ~ • ~ • ~ ~ ~ ~ ~ ~ ~ ~ ~ " " " ~ ~ ~ Suspl1Z1l; Daees • = Present *=Wet; NotCoUect!d e=Dry Note: Sempling dates before 2314 cliffer among pools ~ =Peak abundance Morgan AfbOtetum: 1314, l,Sf4, 1914 Note: e.bsence ofsymbolfottpoolindicûes Seœevi11e : 914, 1314, 1614, 2114 • equal numbers coneeud du:ing samplingpenod Wild1ife Area: 1214, t.s14, 19{4 67 • Fig. 27: Seasonality of Larsia sp. in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum Pool #5 * * * * * * *_ * * * * * * * • * * ******** ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~~~~~~~~~~~~~~~ " " " " ~ N N ~ M ~ ~ • N N N SUIP11ng D.~es Fig. 28: Seasonality of Hamischia sp. in various pools (Southwestern Quebec) : April- July 1998 Senneville Pool#l * * * * * * _ * * * * * * * * ••••• * ••• * ••• --,.,.,-rrrrr • ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ N ~ ~ ~ ~ ~ M ~ Q • ~ " • D ~ ~ D " • " _ ~ _ ~ N N N M " " " N N N SUlPl1nq D.~es Fig. 29: Seasonalïty of Polypedilum sp. in various pools (Soutbwestern Quebec) : April- July 1998 Senneville Pool #1 * * * * • * * • • * _. • * • ••••• • * •••••• --,.,.,-rrrrr • -Present :11= =Wet; NotConect!d e=D:y Note: Sampling dates before 23/4 differ mang pools ~ =Peü abundance Morgan Atboretum : 1314, 15/4, 1914 Nole: ablience ofsymboLfora.pooLindicates Senneville: 9/4, 13/4, 1614, 21/4 • equalnumbers conected du:ing nmp1ingpenocl Wilcl1ife Ana: 1214, 15/4, 1914 68 • Fig. 30: Seasonality of Pseudochironomusspp.in various pools (Southwestern Quebec) : April- July 1998 Senneville Pool#l" " " " " " * ,,_ lit ,. ,. ,. ,. ,. ••••• - -.,.".,..,,-rr . ~ . ~ ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ ~ M ~ ~ ~ " ~ ~ ~ G " ~ e " • ~ " " " • ~ N N =~ • " •" • N N N Semp linq Daees Fig. 31: Seasonality of Smittia spp.in varions pools (Southwestern Quebec) : April - July 1998 Senne·.rùle Pool #4 lIll 'le 'le * ** " " " " " " " " " " " • " " _" " • " ••• -- .,.".,..,,-rr • • • • • • • • • • ~ ~ ~ ~ ~ ~ n ~ ~ ~ """"""""""~ ~ M ~ ~ ~ " ~ ~ =• ~ " • = • n =• • • ~ " " • " ~ N ~ M " " • N N N Sempl1.nq Dsees Fig. 32: Seasonality of Zavrelimyia spp. in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum Pool #5 " " " " lit " " " " " " ,. ,. " " • .. " Senneville Pool #3 " " .. " " lit lit .. lit " .. " lit ,. ,. " lit ...... • = Present *=Wet~ NotColleeud e=Dry Nat!: Sampling dates before 2314 diifer emong pools ~ =Peek ~blmdmce MorgmArboretum: 1314, 1514, 1914 Note: ab::ence of::ymboLfou.pooLindic~s S~evme:9/~13/4,161~21/4 • equ& numbers collected ciu:ing ~amp1ing pe:ioci W21cDife Area: 1214, 1514, 1914 69 Fig. JJ: Seasonality of Eristalis spp. in various pools (Soutbwestern Quebec): April- July 1998 Morgan Arboretum ... Pool #3 A A A A A •• * * * *- • • •• • * • •• • •• • Pool #4 A A '* A * * * * - * •• • • ••• * • •• A ••• Pool#5 • * A A A -*--**'*. * • A • • * • • A * Senneville '* " Pool #1 A A A " * A • '* * •• • _'* • • • •• • • • • Pool#2 • A A A • " • * • - A • A * * A • • • • • ·" ". • • • • Pool #3 "" A A A · .. III " " * '* " .. A * * * * '* A * * * • • • • Pool #4 A • * A A A • r ••• AAA ••••• ·-TTTTTTTT !azç11nq Ilates Fig. 34: Seasonality ofHydroporus spp. (Adults) in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum " Pool #3 • " "" * • _." • * ••••••• ·"* ••••••. Pool #4 _" " "-" ,,-,, . Pool #5 .. " " " " • " A "" " * * * "_,,. " ""*"""'*" Senneville A • A " " " ,. Pool #1 ." * " " * • * * ••••• " " . ... Pool #2 * • * * _'* * - * _. •• * •••••• ...... *"A.* ••• Pool #3 III * _" * * • _ * • • • • • • * * iii •- Pool #4 • * • "_A * • • • * • • " " • • *- * " " " .,. ... ·Wùdlife ..à.rea ... Po~l #1 ••_." .. _. ••••••••••••••••••• Pool #2 ~"""""''''''''''''''''''''''''''''''''''''''''··TTTTTTTT•••• A ••••••• ••••••••••••••• ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ ~ M ~ ~ ~ " M ~ =• ~ • • c " ~ c • • ..... ~ ~ ~ ~ . .. ~ ~ ~ 5amp l1nq Dates • -Present ~ • Wet; NotConected e=-:Dty Note: Samp1ing dates before 2314 differ emcng pools ... =Peak abundmce MorgmAfbOfetum: 1314, 1514, 19/4 Not!: absence of symbolfor, po 01 indicates Seœnil1e :914. 13/4. 1614, 2114 equ~numbers eoUected ciuMg samp1ingpe:iod WilcDife AIea: 1214, 1514, 19/4 70 Fig. 35: Seasonality ofLaccophilus maculosus(Adults) in various pools (Southwestern Quebec): April - July 1998 Senneville * *_." ••• Pool #1 """ * " * * " " * * * * * * ••••• ." Pool #2 * * • * • * - * •••••• ---m-rrrrr. ~~~~~~~~~~~~~~~~~~~~ ~ ~ ~ ~ ~ ~ ~ : ~ a • ~ =: ~ ~ == ~ · SamplinÇJ Daee~ Fig. 36: Seasonality ofAgabusspp. (Larvae) in various pools (Soutbwestern Quebec) : April- July 1998 Morgan Arboretum Pool #2 "'" *- " " ••• • • •• • • • • • * ••• Pool #3 _",,_.. • A • ..- • A A •• * •••••• ~ • ••• • * Pool #4 _A A_A A A A ••••• • • * * ·._... Pool#5 • A A • A .-• " A A •• * " * A A " Senneville " " " " Pool #1 -* .. • • • A A A " " " " .._._..- •••• • • • • • • • • Pool#2 • A ._A A_. • • • • ••••••• * * • ,,_•• Pool #3 te " • •• .. * * "..." " " " " " " " " ... • " . " Pool #4 " ,,_. "-,, t ._.. " • • • " " . •• * " ---m-rrrrr* ... Samp11ng Dates Fig. 37: Seasonality ofColymbetesspp.(Larvae) in various pools (Southwestern Quebec): April- July 1998 SenneWle Pool #4. te • " • • " " • " " • _" • • • • • • "."..... Wùdlife Area Pool#l ". _"" *_ .---m-rrrrr• ••••••• ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ ~ ~ ~ ~ ~ " ~ ~ 0 • ~ " • c " ~ c ~ • ~ " " " " " ft " ~ " " " ft " ft Samp11nq Dates • =Present *=Wet; NotCollected • =Dty Nete:Sampling dates before 2314 differ amongpoa1s ~ =Peak !bun~ce MergmA:bOfetum: 13/4.15/4, 19/4 Note: absence ofsymbolfo:apoolinéicû:s Seœeville :9/4. 13/4, 1614, 21/4 e~ numbe:s colleeteci du:ing $am;Jqpenoe Wild1ife Area: 1214, 15/4, 1914 71 • Fig. 38: Seasonality ofDytiscusspp.(Larvae) i~ various pools (Southwestern Quebec): April ~ July 1998 S~:m~viDe _ Pocl#l •• le le " " "" * * _ ••••• .* •••••• Pool #2 " " " • " " " " " _ ...* .. •••••• ." . Pool #4 Il " " " "" " • " • Il * " ••Il • • Il • " " •• Il ••• ...... ~~...... ~~--TTmT1ï ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~~~~~~~~~~~~~~~ ~ ~ • • • N N N ~ • • • ~ N N surpl1no 1)1l~es Fig. 39: Seasonality of Acilius spp. (Larvae) in various pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum Pool #4 " " " " • " " ".•... •• • • le " ,. . Pool #5 " ." .. • * ... Senn:ville " .* " . - " .... ",. *- Pool #1 " " Il " " " " " " " .... • •• • • . Pool #2 " " • • .. .. •• ...... Pool #3 " " . " ...... Il ,. .. Il '* .. Il •• " le • " * ··t·t Pool #4 " ",...... " " " " " " . --TnTlTTT...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ ~ ~ ~ ~ ~ ~ ~ ~ ~ • • • • • •N N N =~ • • • • •~ N •N • • Surpl1n~ 1).~es • apre::eni CI =uc.ce:Wn 3.bout =pe:ie::S presence (emy 18I'nl stages. g=midemüication o=lj) *= Wei; NOl Conectee! e=Dry Note:S=?~ dates beiore 2314 difÏer amcngpoo~ ~ = ?e~ :lbu:lci=lce Mar~~l-.rCoretum: 1314, 1~!4, 1914 Not!: !b!:ence ofsymbolfortpoolindicÛ!s S~'riI1e :914, 1314, 1614, 2114 e~ numbe.~ conectee! ciu:ng sampliDg penol! Wi1d!ift }.res: 1214, 13/4, 19/4 72 • Fig. 40: Seasonality of Hygrotusspp. (Larvae) in various pools (Southwestern Quebec): April- July 1998 Senne\"iIle Pool #3 ***** * III * _ ** *_*._ ** * A • Fig. 41: Seasonalïty of Hydaticus sp. (Larva) in various pools (Southwestern Quebec): April- July 1998 Morgan Arboretum Pool #4 * A A " " ••• A " A ••••••• A ••• A ••• ... . . ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ l"' l"' ~ ~ l"' . ... . ~ ~ ~ ~ """"""""""~ ~ ~ ~ ~ ~ ~ ~ ~ D • ~ " • • " ~ • ~ • III C\t III D ~ ~ ~ ~ • ~ ft ft ~ • • • ft ft ~ """"~ ... ~ ft C\t SUlp11DfJ Daces • ·Pre~ent Cl =u:lce:t.= ~bout :peeie:' prU=C~ (emy la..~~ ~e=.g=eniéemiiicUion ~ :11: =Vtlet; Not Coneded • =Dty Note: S~q date: belOte 2314 mer among poo~ ~=?e~ab~ce Moq=. A:~erebml. : 13/4, 1~/4, 19t4 Note: tb::ence ofsymboiter l pool indicÛls Se=e'?iIle :914, 1314, 1614, 2114 • !qutinumbe:: conectee lil:ing ~mplingpe:cd Wild!iie A:e~ 1214, 15/4, 1914 73 Fig. 42: Seasonality ofAnacaena /imbata (Adults) in varions pools (Southwestern Quebec) : April - July 1998 Morgan Arboretum Pool #5 " • " • • " • • • • _. - * • • ... * " * *-* •• Senneville Peol #1 _. • " t * * * •••••• **.,. • .,. ••• Pool #2 " • • • * • * * _,. lit •••••• * .,. •••••• Pool #3 "'" :* _ * _ • _" • _ * Pool #4 " • • :* * :* • * • • •• • * ta * lit • • * ---.,.-.,. . Wddlife AIea Pool #2 *"""_. ••••••••••••• --TTTTTnT• ••••••• ~ ~ ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ ~ ~ ~ ~ ~ ~ ~ ~ c • ~ ~ • c ~ ~ = ~ • ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ Sempllnr;r Dace~ Fig. 43: Seasonality ofHelophonls spp. (Adults) in various pools (Southwestern Quebec) : April - July 1998 Morgan .Arboretum Pool #3 • 1\ A 1\ * • * •• _ •••••••• • * * ••••• Pool #4 • .,. A .,. * 1\ ••_,. 1\ ••••••• A * • e •••• Pool #5 _* ,. •• * " lit lit * lit •• * .... * ._* .. * * Senneville Pool #1 " " .,. ,,_. * .,. * .,. lit .,. _ •••••• • • * .lIt ••• Pool #3 • " * :* * * * ,. lit • _ lit * • :* _ lit - * • .,.A.* •••• Pool#4 " • .,. ••• * * * • _. * • • .1iI. 1\ • • ••••••• Wddlife Area Pool #2 • ...===~IIt;..:.~.:..:.:.~.~.~.~.~.~.;..;.~.~.~.~.~ --TTTTTnT••••e ••• Semp11nq Dace:s • =Pre~eni [J =unce:t:in ~bout =pecie~ pn=mC! (emy la..~ stagt= ·g~m iëe:Umcation ocl~ :Je =Vtlet; NotConec+.ed e=Dry Not!: SU1p~ ciù.!: bef'ore 2314 diiÏer amen; pools ~ =Pe~ 3.bu:l~c! MQrg~ A:boretum.: 13/4, 1~!4, 19{4 Hou: ab=ence of symeal for lpaCllindic~s Se:ml!~e :9!4, 1314, 1614, 2114 e~numbm coUect.ed ciu::ng ~amplingpe:icc! Wild1iie J.t!1: 1214. 1514, 19(4 74 Fig. 44: Seasonality ofBerosusstriatus(Adults) in various pools (Southwestern Quebec) : April- July 1998 Senneville Pool #1 " " * * * Il * * * * A * * •• • • • * " * • * ••• A 'Il • 'Il Pool #4 * * * *.* *... " 'Il • " * Il Il • * ••• • * " • V.rùdlife Area " Pool #1 .. " .• • • • • • • ••• • • •••••••• Pool #2 .. ..•• • • • • • ••• • • .-'TTmTTT•••••••• IG C"" C"" C"" roo 1"'> 1"'> roo CI'\ t'4 l:l CI'\ l"l \C = l"l """"C'I ...... t'4 t'4 Sampllnq Oat.e~ Fig. 45: Seasonality ofHydrobius spp. (Adults) in various pools (Southwestern Quebec): April- July 1998 Morgan J..rboretum Pool #5 * * * * * * *_ A * * _ * A • * * * *. * A .... * Senneville Pool #3 • * * * • • .. • * • • • • • * • A * • * A.**** •• P.,ol #4 " * • • le le. • • • le • A A A • A • A. " --'TTmTTT. . Seunpl1nQ Dat.e:s Fig. 46: Seasonality ofHydrochara obtusata (Adults) in various pools (Southwestern Quebec): April- July 1998 Senneville Pool #3 ""* ••••••••••••" " •• " " --TrTTTnT...... • =Presem Sampl1nq Daces ,,= Wet; Not.CoUected e=Dry Nate: Sampling dates belOte 2314 di±fe: among pools ~ =Peak llbundmce Morgan ArbOfetum : 1314, 1514, 19/4 Nou: absence ofsymbolfor l poolindicùts Sennmle :914, 1314,1614, 2114 equd numbers conect!d duœg samp1ing penod W"llcDife Arta: 1214, 1514, 1914 7S Fig. 47: Seasonality of Cymhiodytaspp.(Adul~)in variou~ pools (Southwestern Quebec) : April- July 1998 Morgan Arboretum Pool #4 -***.***** * ••••••• * 1\ * • * ••• Pool #5 1\ * * 1\ * * * * 1\ * * * _* 1\. * * ******** ...... ,.... ~~ .... --TTTrTTTT ~ ~ ~ ~ ~ ..... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ N ~ ~ ~ ~ ~ ~ ~ ~ ~ e ~ ~ e ~ ~ ~ ~ ~ ~ ~ N N ~ =~ • ~ •~ ~ ~ ~ N Sampl1nq Daee:s Fig. 48: Seasonality ofHelophorusspp.(Larvae) in various pools (Southwestern Quebec) : April- July 1998 Senneville Pool #2 1\ *. 1\ ** •••••• -*~ * * * * * * * • • • • • •• Pool #3 1\. • A •• * •• * •• _. *.• * * * • * * • * • • * • Pool #4 A * • * * •• • • • • • • • * • • ••••••• - --TTTTTITT ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ N ~ ~ ~ ~ ~ ~ ~ ~ c • ~ • ~ • ~ ~ ~ ~ ~ N N N =~ • " •~ ~ ~ " N Supl1nQ Dates Fig. 49: Seasonality ofHydrobiusspp.(Larvae) in various pools (Southwestern Quebec): April- July 1998 Morgan Arboretum Pool #4 1\ A • • * • A A A 1\ • •._.• ••1\ •• • • • • • • • • • Pool #5 1\ • • • • • A * • • • • 1\ • • • A • • • SenneWle ·.. Pool #1 1\ • 1\ • • • * ••*_._'" .... • • • • • • • • • • Pool #2 1\ 1\ • • • • • • ••••• ••••• • • • • •• •• • • Pool #3 1\ • 1\ • • ._...... 1\. • • • •••••.... • • • • • • Pool #4 • * • • • A • 1\ • • • 1\ •• * • • --TTTTTITT• • • • =Present )1( = Wet~ NotConectecl e=Dry Note: Samp1ing dates before 23/4 differ emong pools ~ =Peak abundmce MorgmArboretum: 1314, 1514, 1914 Note: llb~ence ofsymbolforlpoolindi:~s Senneville: 9/4, 13/4, 1614, 2114 • e~ numb ers conected du:ing sa:t;lqpe%Ïod WildIif'e Area: 1214, 1514, 19/4 76 • Fig. 50: Seasonality ofHydrochara spp. (Larvae) in various pools (Southwestern Quebec) : Apr~l- July 1998 Morgan Arboretum Pool #5 ***** .. .. * t .. * • .. .. Senneville Pool #3 * ...... * ...... * - * *. • .. * •• *** •• Pool #4 ...... • .. .. ** • • • • _ • * .. • * • * * . --,.,-rrrrrr ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ a _ ~ c " • """"""""""_ _ _ _ " _~ ~ ~ =~ • _•" " ~ N ~ Samp l1D; Pa~es Fig. 51: Seasonality ofHydraena spp. (Adults) in various pools (Southwestern Quebec) : April - July 1998 Morgan Arboretum _. Pool #2 .. ••• * •• .. ~.. * • • •• • • • • .. • • • Pool#3 ••• • ...... • • • • •• _llll .. ·•• • • • Pool #4 .llllllll llll llll • ...... • • • • •• • -'- .. ••• • --TTTTTTTT·.. • ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ ~ ~ ~ ~ ~ " ~ ~ c • ~ ~ • c ~ ~ c _ • ~ ~ ~ ~ " ~ ~ ~ -- - .- Samp- Hn;- Dace:!S Fig. 52: Seasonality of Dasycorixa SPI in various pools (Southwestern Quebec) : April- July 1998 Wùd1ife Area Pool #1 ...... A .. _ * ••••••••••• • ••••••• --TfTTTTTT Sapl1nq Daees •• Present * K Wet; NotConected • =Dry Not::Sempling dat!s befOf! 2314 ciiJÏer among pools ~ =Peak abund=ce Mo:gmArbOfetum: 1314, 15/4, 1914 No~: a.bsenee ofsymboliO=tpoolméi:Ù!s S~evme:914,13/~16f4,21/4 • e~numbe:s coneeud duriDg ==np1ingpe:iod Wild1ife Area: 1214. 1.5/4, 19/4 77 Fig. 53: Seasonality ofCallicorxia sp. in various pools • (Southwestern Quebec) : April- July 1998 Wùd1ife hea Pool #1 ...... • A A A A A_a •••••••••••....,. ••TTTTTT1T•••••••• ~~~~~~~~~~~~~~~~~~~~ ~ : : ~ : ~ =: : ~ . ~ =: ==: =" . Sampl1ng Dates Fig. 54: Seasonality of Trichocorixa spp. in various pools (Southwestern Quebec) : .!\pril- July 1998 Senne"ille Pool #1 * Wllcllife .t:..rea * * • • • • • • • ••• • • • • • • • • * •• - ••• Pool #1 * * • • • ._. e • • • • • • • •• • •• •• • • • • --rrrTTTTT ~ ~ ~ • • ~ ~ • • • ~ n ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ N M n ~ ~ • ~ ~ ~ D " ~ D " • • • • • • N N N =~ • " • " N N N • supling.Daees Fig. 55: Seasonality ofLimnephilus spp.in various pools (Southwestern Quebec): April- July 1998 Morgan Arboretum .- Pool #5 .---*_ . ••• e •• •••••••• Senneville .. Pool #1 * • •• •• •••••••• Pool #3 .. * t .. * " * * " • • • ._ . Pool #4 lit • * •.t.. " " " • fil • " .*_ .. " • • • • . .- . Wl1dlifehea . Pool #1 • • • • * *_...... ••• • • --rrrTTTTT•••••••• • =n:sem 'le = Wet~ Not Coneeud e=Dry Note:Sempling dates hafere 23/4 cme: smongpoo1s ..:,. = Peak !l.buné~ce Morgan Arboratum : 1314,1514.1914 Note: absence of~bolfo!~pooliné.i:~!s Se:me~e :9/4, 1314, 1614, 2114 • equ~ numbers conernd du:ing !:e:np1i:lg p!:ioci Wilc!1ife Area: 1214, l.Sf4, 19/4 78 Fig. 56: Seasonality of fronoquia spp.in various pools (Soutbwestern Quebec) : April- July 1998 Scrmeville ... Pool #3 A AA." A "_._A_AAA A" A AA --TTTTTTTT ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ ~ ~ ~ ~ ~ " ~ ~ ~ ~ " " ~ " ~ . . . " " " " " N N N " M ." N N .N Semp11nq Dates Fig. 57: Seasonality ofEuhranchipus bundyi in various pools (Southwestern Quebec): April- July 1998 Senneville Pool #1 t A A " ...... • 1& 1& 1& • 1&: ••• Pool #2 t ._A • •••• • •••••••• Pool #4 * • A • A A A • ._. A •• 1&: • ,. .,. • • AI&: ••••• Wùdlife Arca Pool #1 t •• ••• • •• •• • •••••••• Pool #2 t • • • • • ••• • •••• • •••••••• --TTTTTTTT SaIIlP l 1nI; tlates Fig. 58: Seasonality ofCaecidotaforbesi in various pools (Southwestern Quebec:): April- July 1998 Morgan Arboretum ... Pool #3 1& 1&: • A A A •• ••••• • ••••••• Pool #4 t 1&: ...... _... Pool #5 • • ••.. • • • Senneville .. .- Pool#l •• .. ••••• .. _ . Pool#2 • lA A A .. lA •A A •A ••••••A A 1& A ... . Pool#3 .. A --TTTTTTTT.. .. 1&: 1&: AI&: •• Samp11nq Dates • = Present :le = Wet; NaL Collected .=D%1 NOie: Sampling dates belote 2314 difFer among pools ~ =Peak abundance Morgan Arboretum :1314, 1514, 19/4 Note: absence of symbolfor t poo1inclic8.tes Senneville :914, 13/4, 1614, 21/4 equ& numbers conected du:ing samp1ing period WildJle Alea: 1214, 1514, 1914 79 Fig. 59: Seasonality ofAplexa elongata in various pools • (Southwestern Quebec): April- July 1998 Senneville Pool#2 " ~ ~ ._•••_ ••• _ •••••• A ••••••• Pool #3 • • __ -- • • • • *••••••••• _____·.e. Pool #4 • ,,_. * • • • • • * t • • • • •• A .... e • ·-TlTTTnT • • • • • • • • • • ~ ~ ~ ~ ~ ~ ~ ~ w w """"""""""~ ~ ~ ~ ~ ~ ~ ~ ~ ~ c • ~ c • • • • • ~ " "ft ~ ~ =~ • • • ~ ~ ~ ~ Supl1nq I)ac:e!l Fig. 60: Seasonality ofGyraulusspp.in varions pools (Southwestern Quebec) : _~pril- July 1998 Morgan Arboretum Pool #5 • * • " • • • • * • • " • • • • • * __ A * A " ,,_ Sermeville .... Pool #1 " " " • • * ".... " • _. •••• .•... II: " " " " " II: --_AAA_." •• Pool #3 * • • • * __ * • * • • • * Pool #4 II: • * ~ _. II: _ A • • • • • • ~ " • • • • A" ••••• Wùdlife Area Pool #1 • * " " " • • * ••••••••••• • ••••••• Pool #2 t * * •••••••••••••• • ••••••• ··TlTTTnT • • • • •• • • • • • ~ ~ ~ ~ ~ ~ ~ ~ w ~ """"""""""~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ c • ~ • ~ • • • ~ • • ~ ~ N =~ • • •~ ~ ~ ~ ~ Supl1nq tlates Fig. 61: Seasonality ofStagnicolaspp.in various pools (Southwestern Quebec) : April- July 1998 Senneville .... Pool#l II: II: " •• _._A_ . A • le • " ••• __ le le • A ••• Pool #4 " " A " • • * A " " • A A • A "iIi. • • ·-TlTTTnT ...... ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ """"""""""~ N ~ ~ ~ ~ ~ ~ ~ =• ~ ~ • c • ~ c • • ~ • ~ ~ ~ ~ ~ N ~ • • • ft ft ~ Samp l1nq Dat:es • = Presem * = Wet~ Not Collected • =Dty Note: Sampling dates before 2314 diifer emong pools ... =Peak ll.bundmce MorgmArboretum: 13/4, 1514. 19/4 Note: ll.b~ence of~bolforapoolinc!ic~s SmneWle :9/4. 1314, 1614, 21/4 • equal numbers colleeud c!u:ing $~iing period Wücl1ife Area: 1214, 1514, 19f4 80 Fig. 62: Seasonality of Lymnaea sp. in various pools (Soutbwestern Quebec) : April- July 1998 Morgan Arboretum Pool #5 ft ft ft ft ft ft ft ft.- ft ft ft ft ft * * • * ft * * * * ft ft_ --TnTlTTT Sampl1n~ DIl~es Fig. 63: Seasonality of Sphaertum occidentale in various pools (Southwestern Quebec) : April- July 1998 ~nnevwe .... Pool #1 •• • •• ft _ *. * ••• Pool #2 .. *_t .. .. t .• • • • • -*•• ••• • Pool #3 .ft 1\ * 1\ * •• Pool #4 t ._. _A. * • •• --TnTlTTT • • •••••• • • ~ ft ~ ft ft ~ ft ft ~ ~ """"""""""~ ~ ~ ft ~ ~ • ~ ~ 0 • ~ " • • " ft • " • . " " " " ~ ~ ~ ~ " .. " " ~ S1lZllP11n~ D.~es • -Present ;le =Wet; NotCollected e=Dry Note:SempJing dates before 2314 ditÏer amongpools ~ = Peak abundmce MorganMoretum: 1314, 1.5/4, 19/4 Note: absence of symbo1 for t pool inâicms Senneville: 914, 13/4, 1614. 2114 equal numbers collect!d duzing sampling penod WücJ1ife Area: 1214, l.SI4, 19{4 81 • Fig. 64: Percentage Abundance of Aedes species Morgan Arboretum Pool #2 (SW Quebec) * 1314 1514 19/4 2314 2714 3014 415 7/5 1115 2916 2J7 617 Date • Ae. canadensis Ae. cinereus • Ae. communis • Ae. diantaeus ~ Ae.euedes lIiI Ae.excruc~ns Iii Ae. intrudens • Ae. provocans • Ae. punctor lIiI Ae. vexans • Aedes species .. Only sampling dates when specimens were collected have been included • 82 Fig. 65: Percentage Abundance of Aedes species Morgan Arboretum Pool.3 (SW Quebec) * 100%- 80%- 60%- • 1314 15/4 19/4 2314 27/4 30/4 415 7/5 11/5 29/6 217 en • Ae. canadensis • As~:""'unIs • Ae. diantaeus ~ Ae. excrucians • Ae. provocans • Ae. punetor • Ae. stimulans Il Ae. vexans • Aedes Species • • Only sampling dates when specimens were collected have been included 83 Fig. 66: Percentage Abundance of Aedes species Morgan Arboretum Pool #4 (SW Quebec) * 100%, 80%, 60%- 13/4 15/4 19/4 2314 27/4 30/4 4/5 7/5 29/6 217 6n Date • Ae. canadensis Ae. cinereus • Ae. communis • Ae. d/antaeus III As. excruc/ans Iii Ae. intrudens • Ae. provocans • Ae. punetor • Ae. st/mu/ans Il Ae. vexans • Aedes species * Only sampling dates when specimens were collected have baen included 84 Fig. 67: Percentage Abundance of ~ species Morgan Arboretum Pool #5 (SW Quebec) * 100%- 80%- 60%- 13/4 15/4 19/4 2314 27/4 30/4 4/5 7/5 11/5 14/5 29/6 217 6fT 9n 1617 Date • Ae. canadensis Ae. cinereus • Ae. diantaeus III Ae. euecles Ae. excrucians Ae. intruclens III ii • Ae. provocans • Ae. punctor • Ae. stimu/ans Ae. veJ(sns III • Aedes species .. Only sampling dates when specimens were collected have been included 85 Fig. 68: Percentage Abundance of Aedes species Senneville Pool #1 (SW Quebec) * 9/4 1314 16/4 21/4 2314 27/4 30/4 4/5 7/5 29/6 217 en Date • Ae. communis [Ill Ae. euedes iili Ae. excrucians • Ae. provocans • Ae. stimulans • Ae. vexans • Aedes species * Only sampling dates when specimens were collected have been included 86 • Fig. 69: Percentage Abundance of Aedes species Senneville Pool #2 (SW Quebec)· • 9/4 1314 16/4 21/4 2314 27/4 30/4 715 14/5 29/6 217 Date • Ae. communÎs • Ae. euedes IlAe. excrucians • Ae. provocans • Ae. stimulans III Ae. vexans • Aedes species • * Only sampling dates when specimens were collected have been included 87 Fig. 70: Percentage Abundance of Aedes species Senneville Pool #3 (SW Quebec) * 9/4 13/4 16/4 21/4 2314 30/4 415 en Date • AB. canadensïs • Ae. communis Iii Ae. excrucians • AB. provocans • Ae. stimulans • Aedes species * Only sampling dates when specimens were collected have been included 88 Fig. 71: Percentage Abundance of Aedes species Senneville Pool #4 (SW Quebec) * • 9/4 1314 1614 21/4 2314 27/4 30/4 415 11/5 29/6 2rl Date • Ae. canadensis Ae. clnereus • Ae. communis • Ae. suedes • As. provocans • As. st/mu/ans III As. vexans • Aedes species • • Only sampling dates when specimens were collected have baen included 89 • Fig. 72: Percentage Abundance of Culex species Morgan Arboretum Pool #5 (SW Quebec) 100%· • 0%· I--~==-----+-- sn 9n 13/7 16n 20n Date • ex. pipiens • ex. restuans • ex. territans • * Only sampling dates when specimens were collected have been included 90 • Fig. 73: Percentage Abundance of Cylex species Senneville Pool #3 (SW Quebec) * 100%·~~~;- 80%- 60%- • 415 14/5 29/6 217 6n 9n 13/7 Date • Cx. pipiens • Cx. restuans • Cx. territans • Culex species • .. Only sampling dates when specimens were collected have been included 91 • Fig. 74: Percentage Abundance of Chironomidae Morgan Arboretum Pool #2 (SW Quebec) * 100Cfo-lIllf • 13/4 15/4 19/4 2314 27/4 30/4 2fT Date • Corynoneura spp. Il Doithrix spp. • Limnophyes spp. • Phaenopsectra spp• • * Only sampling dates when specimens were collected have been included 92 • i 1 Fig. 75: Percentage Abundance of Chironomidae i Morgan Arboretum Pool #3 (SW Quebec) * \ i 100%- ~~~~=-- 1 1 1 \ \ ! \ \ 1 1 i 1 • i 1 1 1 \ 0%- 13/4 15/4 19/4 2314 27/4 1 Date 1 1 \ Doithrix spp. • Umnophyes spp. 1 II ! • • Only sampling dates when specimens were collected have been included 93 • Fig. 76: Percentage Abundance of Chironomidae Morgan Arboretum Pool #4 (SW Quebec) * 100%- • 13/4 15/4 19/4 2314 27/4 4/5 Date III Corynoneura spp. iii Doithrix spp. • Hydrobaenus spp. • Umnophyes spp. • Phaenopsectra spp• • • Only samplig dates when specimens were collected have been included 94 Fig. 77: Percentage Abundance of Chironomidae Morgan Arboretum Pool 15 (SW Quebec) * 131415/419/4231427/430/4 415 715 11/514/521/529/6 217 6n 9n 1317 16n 20n Date • Chironomus spp. IlDoithrix spp. Hydrobaenus spp• • Larsiasp. • Umnophyes spp. • Phaenopsectra spp. • Zavrel/myia spp. • Only sampling dates when specimens were collected have been included 95 Fig. 78: Percentage Abundance of Chironomidae Senneville PooI'1 (SW Quebec) * 9/4 1314 16/4 21/4 2314 2714 30/4 4/5 7/5 11/5 14/5 18/5 1317 Date • Chironomus spp. • Corynoneura spp. iii Hamischia sp. • Limnophyes spp. • Phaenopsectra spp. • Polypedi/um sp. • Psectrotanypus spp. o Pseudochironomus spp. * Only sampling dates when specimens were collected have been included 96 • Fig. 79: Percentage Abundance of Chironomidae Senneville Pool'2 (SW Quebec)· • 1314 1614 11/5 14/5 Date • Chironomus spp. Umnophyes spp. • • Only sampling dates when specimens were collected have been included • 97 Fig. 80: Percentage Abundance of Chironomidae Senneville Pool'3 (SW Quebec) * 60%- 1314 4/5 11/5 1415 1815 21/5 2515 2815 1/6 416 29/6 2ft en 9n 1317 16n Date • Chlronomus &pp. • Co/)'llOll8UIlI &pp. Umnophyes spp. • PsectlOtanypus &pp. 0 ZavllItimy/a &pp. • Only sampling dates when specimens were collected have been included 98 Fig. 81: Percentage Abundance of Chironomidae Senneville Pool #4 (SW Quebec) * 100%·r==~ 80%, 60%· 13/4 415 7/5 11/5 14/5 21/5 2515 29/6 Date • Chironomus spp• • Umnophyes spp. • Smittia spp. • * Only sampling dates when specimens were collected have been included 99 Fig. 82: Total Number of Taxa Callected Per Pool in Relation ta it5 Hydroperiod 50 ..,....------, 40 ------ca x .....ca o 30 ~ ID oC E ::J Z 20 Cü o .....- 10 o W2 W1 M3 M2 M4 52 51 54 83 M5 Pools (lncreasing hydroperiod =» Hydroperiod of Pools (Days): Morgan Arboretum Senneville Wildlife Area M2: 38 51:49 W1: 22 M3: 37 52:40 W2: 14 M4:38 53:78 M5:79 54:56 • 100 .... Fig. 83: Taxa Collected inWildlife Area Pool #1 (Southwestern Quebec) : April- July 1998 Anostraca Gastropoda " " Trichoptera * -* Odonata * " Chironomidae -- " Culicidae Dytiscidae " Hydrophilidae le " .. Corixidae le le * Gerridae A " " .. 1 1 rÜRY- "-.. .. • ~ ~ r- P4 "CllI "CllI Samp~Dates Fig. 84: Taxa Collected inWildlife Area Pool #2 (Southwestern Quebec) : April- July 1998 Anostraca Gastropoda Cbironomidae Culicidae * Il Dytiscidae Hydrophilidae * Gerridae * t r: --- .. DRY "0\ fI4 Samp~Dates • =Present Il =Wet; Nct conected 101 • Fig. 85: Taxa Collected in Morgan Arboretum Pool #2 (Southwestern Quebec) : April- July 1998 Chaoboridae Il le le le A le Chironomidae .. * le .- ... A Culicidae !lpulidae " A le A • Il Il Il Il Il Il Il -Il Dytiscidae • Il _ A. A A " A A le Il Hydraenaidae Il * A " " A le A le _AA A Gerridae ft A A A le A le A A A Il A A Sampling Dates Fig. 86: Taxa Collected in Morgan Arboretum Pool #3 • (Southwestern Quebec) : April- July 1998 Isopoda " " le " " " Il " * Chaoboridae A A Il " * Chironomidae " A A ,. ,. " " Culicidae _ Ttpulidae Il • Il A Il A ,. Il A * Il le Syrphidae le le Il le Il le _ le A le .. Dytiscidae A • Il " _ A l1li le le A * Hydraenaidae" A " ,. 111 "le A 111 • A le Hydrophilidae 1: • A " Il "le ." le " Il Gerridae le Il le " le "le Il le •••11TA A .. ••• DRY '41 r- r- DRY a'\ C'II '41 '"C'II Sampling Dates • • =P:esent *=W:t~ 1~ ct Col1~d=d Fig. 87: Tax~ Collected in Mor2an Arboretum Pool #4 102 (Southwestern Quebec) : April- July 1998 Isopoda • •• * • Chaoboridae • • • • • Chironomidae ._.1. * *• • Culicidae • • ltPulidae • A • A 1\ * ...... -.. Il Il • 1\ A __* Syrphidae Il A " • Il " " Dytiscidae 1\ le .." •II: Hydraenaidae Il - ,.." Il Il " • Hydrophilidae .1\ 1\ 1\ A le • le A _" 1\ Gerridae le A A_* ...... _".. . .. SampliDg Dates Fig. 88: Taxa Collected in Morgan Arboretum Pool #S (Southwestern Quebec) : April- July 1998 Isopoda ••••••••••• _A_A_ ..Amphipoda .Ie le - Gastropoda A le A • 1\ • Il • le Il * * le -A* ." •• AIe_ Trichoptera Il ••_" .. _ •• * • le A " 1e._"AAA. Chaoboridae - A •••• *._ Dixidae Il Il le le le le _ A A .• A .AIe"AA"" Chironomidae • .. A Culicidae ••••••••• Il " 1\ 1\ ...... ~ Syrphidae 1\ 1\ ..." • Il Il .. A .. . -_ ..... " Dytiscidae _" " .... * • •••• " .. * * • " • " Hydrophilidae _ A A A •• .. " A_"."***. Getridae Ill,. ,. Ill.A * .. • _ _ A A .,. *1e""*AIe* Sampling Dates • =Present le =Wet; NotCollected 103 • Fig. 89: Taxa Collected in Senneville Pool #1 (Southwestern Quebec) : April- July 1998 Anostraca • * * * " . " Isopoda le A 1& • Bivalvia A_'" -* Gastropoda * ." Trichoptera * .- * " * -te Odonata A * " •• " .... " " " " " Tipulidae .. A '" " • A A te " te Chaoboridae -"A *... A A_"_ "A • " " A AI\~.A.A Dixidae te te A A A 'li A " 1& • Chironomidae " " Culicidae . - Syrphidae " * * '" .. ,,1\ ft "_A 'li A A - Dytiscidae A_ .. " Hydrophilidae " -*-* _ft " " Corixidae -*" " * ". ft- ,,_ .. " ,. 1& " Gerridae . 1& 1\ "AA"AI&A *A 1\ Sampling Dates • • =Present :le = Wet; Not CoUected 104 • Fig. 90: Taxa Collected in Senneville Pool #2 (Southwestern Quebec) : April- July 1998 .Anostraca *-* * * Isopoda *-***-**** * * Bivalvia * Gastropoda * "-,, *-* _.- le te Tipulidae * le_le,. Il .. le A A" -"* " Chaoboridae " le_A A *_ AA Dixidae le A* 1\ A * *-* * * le te • Chironomidae Alele_ *-* ** * * Culicidae ... Syrphidae A_********* • -* A Dytiscidae * A_. _*_* * Hydrophilidae • *_. " ....* • * • Gerridae A A A le * ,. * _* * * * * ...,..,.--- ~ ...... ~ ~ ~ ~ DRY 'G DRY ~ ~ ~ ~ ~ ~ =• ~ ~ • """"'"f"t f"t N N N ~ fIII fIII "'"N N Sampling Dates • • =Present le =Wet; NotConected 105 Fig. 91: Taxa Collected in Senneville Pool #3 (Southwestern Quebec) : April- July 1998 Ephemeroptera '= le AA A le A 1e.1e le le * le le * * Isopoda '=. AA A A_. le * A le. * * * " Bivalvia .* . Gastropoda *AAIe**•••••••••• •. _-- Trichoptera **••••••AAAIcIcIcIcIe Chaob oridae *.*A.* A •••••• Cbironomidae A.lelelelele_•••••••• Culicidae * le_A 1e •• 1e • le * le Syrphidae *AIe**.* Ale le le Al * Dytiscidae ••**.A.Ie •••••••• Hydrophilidae Gerridae SampiDgDates • = Present le =Wet; NotConected 106 • Fig. 92: Taxa Collected in Senne,ille Pool #4 (Southwestern Quebec) : April- July1998 Anostraca ,. * * * * *.* * * .. * * * " * * * .. Bivalvia • .. Gastropoda ._._...••_- " " .. ft ft •• _ ••• _,.. * .,. . Trichoptera -*... ,. .. Tipulidae * _. * * ,. .... " ...... " ." .. Chaoboridae ." * • ,. •• • .. te .. • Dixidae " * • le ,. .... _* * * .... 111 " * * _ .. le * Cbironomidae ._.***. * .. Culicidae * :1: Syrphidae ---...... _.*- • * .. le .. Dytiscidae * .. le " Hydrophilidae • Genidae SampliDg Dates • = Present *= Wet; NotCollected 107 Appendix 1: Location ofPools • Island of ~Iontreal • M: Morgan Arboretum S: Senneville • W: Stoneycroft WildIife Area Scale: 1.8 cm =1km e • • Appendix 2: Description of Temporary Snowmelt Pools in Southwestern Quebec, 1998 Pools Code Max. water depth (cm) Max. length (m) Max. width (m)- Description of Pools Morgan Arboretum Pool # 1 Ml ------Pool omitted trom project ------Pool # 2 M2 23 15.5 14.9 - pools found in remote woodland area surrounded Pool ## 3 M3 19 27.7 16.5 mainly by coniterous trees Pool ## 4 M4 15 25.6 18.3 - low exposure to direct sunlight; shaded Pool # 5 MS 15 26.6 24.7 - substrate of pools consists mostly of pine needles, deciduous leaves, branches and bark - not easily accessible - no permanent water body nearby Senneville Pool # l 51 45 26.8 15.5 - pools found in a woodlot near public park Pool # 2 52 27 23.8 18.6 surrounded mainly by deciduous trees Pool ## 3 53 62 26.S 5 - direct exposure to sunlight early in season Pool ## 4 84 80 24.7 22.6 - substrate of 51 pool consists mostly of stones, deciduous leaves, branches and moss - substrate of other pools conslsts of mostly deciduous leaves and branches - easily accessible - permanent water body nearby; Ottawa River approx. 200 m away Wildlife Area Pool ## 1 Wl 98 13.7 7.5 - pools found in open grassland; few trees Pool # 2 W2 57 17.4 14.9 - direct exposure to sunlight throughout season - substrate consists mostly of grasses - easily accessible - permanent watar body nearby; Stoneycroft Pond approx. sa m away • Maximum width recorded does not necessarily correspond ta the same sample date as maximum length recorded -o GD 109 Appendix 3: Morphometric and Water Temperature Data of Vernal Pools in Southwestern Quebec, 1998 Senneville Pool #1 (SW Quebec) Date Water Temperature (OC) Maximum width (m) Maximum length (m) 9/4 15 15.5 26.8 13/4 15 15.3 26.7 16/4 15 15.3 26.7 21/4 13 15.1 26.3 23/4 19 13.5 26.5 27/4 10 11.5 23.8 30/4 17 11.5 22.8 4/5 19 11 22.8 7/5 20 10.5 22.8 11/5 16 8 19 14/5 21 7 15 18/5 20 2 pools (2mx2m) 29/6 20 10 10 2/7 18 10 5 6/7 20 3 pools (2mx2m) 13/7 19 3 pools (2mx2m) Average = 17.3 Senneville Pool #2 (SW Ouebec) Date Water Temperature (OC) Maximum width (m) Maximum length (m) 9/4 15 18.6 23.8 13/4 15 18.6 22.7 16/4 15 17.4 22.7 21/4 13 12.4 17.5 23/4 19 10.7 13.7 27/4 10 8.8 12.4 30/4 17 7 12.4 4/5 19 6.6 12.4 7/5 20 5J 12.4 11/5 16 1 pool (2mx2m) + 1 pool (5mx1 m) 14/5 21 1 5 29/6 20 1 5 217 25 0.3 10 Average = 17.3 110 Appendix 3 (cont-d): Morphometric and Water Temperature Data • of Vernal Pools in Southwestern Quebec, 1998 Wildlife Area Pool #1 (SW Quebec) Date Water Temperature (OC) Maximum width (m) Maximum length (m) 12/4 14 7 9.1 15/4 10 7.5 8.1 19/4 la 7.4 8.5 23/4 20 5.2 5.2 27/4 la 3.3 13.7 Average =12.8 Wildlife Area Pool #2 (SW Quebec) Date Water Temperature (OC) Maximum width (m) Maximum length (m) 1214 17 14.9 17.4 15/4 10 12.9 10.9 19/4 la 0.3 2 Average =12.3 • Morgan Arboretum Pool #2 (SW Quebec) Date Water Temperature ( OC) Maximum width (m) Maximum length (m) 13/4 15 9.8 12.5 15/4 la 10 12.5 19/4 10 14.9 15.5 23/4 19 8.2 10.4 27/4 10 12.1 30/4 18 3 pools (2mx2m) 4/5 19 3 pools (2mx2m) 7/5 18 4 pools (2mx2m) 11/5 16 3 pools (2mx2m) 29/6 20 5 pools (2mx2m) 217 20 4 pools (2mx2m) 617 14 3 pools (2mx2m) 1317 19 3 pools (2rnx2m) • Average = 16 111 Appendix 3 (cont1d): Morphometric and Water Temperature Data of Vernal Pools in Southwestern Quebec, 1998 Senneville Pool #3 (SW Quebec) Date Water Temperature (OC) Maximum width (m) Maximum length (m) 9/4 12 5 26.5 13/4 15 3.4 26.3 16/4 15 3.4 26.2 21/4 13 3.2 25.5 23/4 19 3 25 27/4 10 3 24.5 30/4 17 2 16.5 4/5 19 2 16.5 7/5 20 2.5 16 11/5 16 1.5 16 14/5 21 1 16 18/5 21 1 6 21/5 18 1 6 25/5 20 1 6 28/5 22 1 pool (1 mx3m) + 1 pool (1 mx5m) 1/6 17 1 10 4/6 17 1 10 29/6 20 1 10 2fl 18 1 10 617 22 1 9 917 22 1 9 1317 19 1 9 1617 26 1 pool (1 mx5m) + 1 pool (1 mx4m) Average =18.2 Senneville Pool #4 (SW Quebec) Date Water Temperature (OC) Maximum width (ml Maximum length (m) 9/4 12 22.6 24.7 13/4 14 22.6 24.7 16/4 15 20.6 22.6 21/4 11 21.2 22.6 23/4 19 16.7 21.6 27/4 10 14.7 19.6 30/4 17 12.7 16.5 4/5 19 8.7 12.6 7/5 20 8 12 11/5 16 8 12.5 14/5 16 8 12.5 18/5 17 7.9 14.9 21/5 18 7.9 14 25/5 16 2 pools (2mx2m) 1/6 17 4 pools (2mx2m) 29/6 20 5 pools (2mx2m) 2f7 18 5 5 617 20 1 1 Average = 16.4 112 .. . Appendix 3 (cont1d): Morphometric and Water Temperature Data of Vernal Pools in Southwestern Quebec, 1998 • Morgan Arboretum Pool #3 (SW Quebec) Date Water Temperature (OC) Maximum width (m) Maximum length (m) 13/4 15 11.9 15.9 15/4 10 15.6 27.7 19/4 11 16.5 18.6 23/4 19 15.5 16.5 27/4 10 13 14.2 30/4 18 4 pools (2mx2m) 415 19 4 pools (2mX2m) 7/5 18 2 pools (2mx2m) 11/5 17 4 pools (2mx2m) 29/6 20 5 pools (2mx2m) 217 20 5 pools (2mx2m) sn 16 2 2 Average = 16.1 Morgan Arboretum Pool #4 (SW Quebec) Date Water Temperature (OC) Maximum width (m) Maximum length (m) 13/4 15 15.5 17.4 15/4 12 16.2 22.6 19/4 11 18.3 25.6 23/4 19 14.6 17.1 27/4 10 15.1 16.6 30/4 18 4 pools (2mx2rn) 4/5 19 4 pools (2rnx2rn) 7/5 18 5 pools (2mx2m) 11/5 16 2 pools (2mx2rn) 29/S 20 7 8 217 18 5 7 6n 18 3 pools (2mx2m) 13n 19 4 pools (2mx2m) Average = 16.4 • 113 Appendix 3 (cont-d): Morphometric and Water Temperature Data of Vernal Pools in Southwestern Quebec, 1998 • Morgan Arboretum Pool #5 (SW Ouebec) Date Water Temperature (OC) Maximum width (ml Maximum length (m) 13/4 16 20.2 22.6 15/4 10 23.2 26.2 19/4 11 24.7 26.6 23/4 19 21.6 25.4 27/4 10 23.6 24.2 30/4 18 21.4 22.6 415 19 22.6 22.9 7/5 18 22.3 22.4 11/5 16 21.4 23.3 14/5 19 17.8 19 18/5 20 8 pools (2mx2m) + 1 pool (4mx3m) 21/5 18 6 pools (2mx2m) + 1 pool (1 Omx1 am) 25/5 18 2 2 1/6 15 2 2 4/6 15 1 4 29/6 20 17 18 217 18 15 16 6n 18 15 16 • 9n 19 15 16 13n 19 14 14 16n 26 7 pools (2mx2m) 20n 23 4 pools (2mx2m) + 1 pool (3mxSm) 23n 20 4 pools (2mx2m) + 1 pool (3mxSm) Average = 17.6 114 Appendix 3: Average Air Temperatures and Total Precipitation for April- July, 1997·1998 Year: 1997 Month Average Temp. (OC) Total Precip. (mm) April 4.8 140.1 May 10.6 78.6 June 19.5 88.1 July 20.1 303 Year: 1998 Month Average Temp. (OC) Total Precip. (mm) April 7.9 32.6 May 16.9 71.3 June 18.5 192.6 July 20.3 76.7 Yearly Average Month Aveiage Temp. (OC) Total Precip. (mm) April 5.9 70 May 13.1 70.8 June 18.1 88.3 July 21.1 89.7 115 • References Abell, D.L. 1981. Benthic invertebrates ofsorne California intermittent streams. Pages 46-60 in S. Jain and P. Moyle, editors. Vernal pools and intermittent streams. A Symposium Sponsored by the Institute of Ecology, University of California, Davis. Alaire, Y. and LeClair, R. 1988. Water beetle records from shallow pools in southern Quebec (Coleoptera: Dytiscidae). The Coleopterists Bulletin 42(2): 33-338. Baldwin, W.F., James, H.a. and Welch, H.E. 1955. A studyofpredators ofmosquito larvae and pupae with a radioactive tracer. The Canadian Entornologist 87: 350-356. Batzer, D.P. and Wisseger, S.A. 1996. Ecologyofinsectcommunities innon-tidaI wetlands. Annua! 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