The biology of temporary waters

343 Pages·2006·5.724 MB·English

by  D Dudley Williams

The Biology of
Temporary Waters
D. Dudley Williams
University of Toronto at Scarborough, Canada
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Thebiologyoftemporarywaters/D.DudleyWilliams.
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Preface
Temporarywatersarefascinatingvenuesinwhich the applied, to the conceptual. Each has contri-
tostudythepropertiesofspecies,asthelatterdeal buted something to our knowledge base, yet this
with the day-to-day business of living in a highly information remains largely scattered, in need of
variable environment. Obligate temporary water collation and synthesis. Several worthwhile
species display a remarkable array of adaptations attemptshavebeenmadethrough‘specialsessions’
to the periodic loss of their primary medium that atrecentconferences,however,thereremainslittle
largely sets them apart from the inhabitants of integration. Perhaps, the available data remain a
permanent water bodies. Survival of individuals littletoopatchyandthesubdisciplineisstillalittle
frequently depends upon exceptional physio- too immature for a thorough treatment, but hope-
logical tolerance or effective migrational abilities, fullythisbookisastepinthatdirection.
and communities have their own, distinctive hall- Ihavemanypeopletothankforhelpingmeput
marks. Quite apart from their inherent biological this volume together. First and foremost are sev-
interest,however,temporarywatersarenowinthe eralofmypastandpresentgraduatestudentsand
limelight from a conservation perspective as these postdoctoral fellows who have shared my interest
habitats come more and more into conflict with intemporarywaters,andwhohaveallowedmeto
human activities. Traditionally, many temporary use some of their unpublished data. In particular,
waters,betheyponds,pools,streams,orwetlands, Katarina Magnusson and Oksana Andrushchy-
havebeenconsideredtobe‘wasted’areasofland, shyn have provided information on intermittent
potentiallyconvertibletoagricultureoncedrained. pond faunas in southern Ontario (Chapter 4), and
In reality, they are natural features of the global Ian Hogg has kindly provided information on the
landscape representing distinct and unique habi- faunal changes along the Murrumbidgee River,
tats for many species—some that are found Australia (Chapter 10). I am also grateful to those
nowhere else, others that reach their maximum colleagues who have allowed me to reproduce
abundance there. photographs and figures from their published
In1985,thelateW.D.Williamslamented‘....The works,andwhoareacknowledgedbynameinthe
extent of reference to temporary waters is not in figure legends. Several of these same colleagues
accord with their widespread occurrence and also provided encouragement to undertake the
abundance,ecologicalimportance,norlimnological writingofthisbook,andIhopethatthecompleted
interest’. In 1987, I published ‘The Ecology of product does not disappoint them. I would also
Temporary Waters’ which was a first attempt to like to formally thank Diane Gradowski and Ken
gather together the highly scattered literature on Jones of the University of Toronto at Scarborough
these fascinating habitats. Gratifyingly, since Bill graphics department for their help with many
Williams’lamenttherehasbeenasteadyincreasein of the illustrations, and the Natural Sciences and
thestudyoftemporarywaters,andmanyresearch Engineering Research Council of Canada for
articleshavebeenpublishedthroughouttheworld. financial support of my research. Thanks, too, go
The latter range from the highly descriptive, to to Annette Tavares for the cover design.
vii
viii PREFACE
On a personal note, I am grateful to my family, thought, and to Bronwen for always being happy
Judy, Siaˆn, and Owen, whose support and com- to see me.
panionship helped me complete what turned out D. Dudley Williams
to be a far bigger project than I had originally Toronto, May 2005
Contents
1 Introduction 1
1.1 Whataretemporary waters?.. ..... .... .... .... .... .... ..... .... .... .... .... ... 1
1.2 Biologicalimportance... .... ..... .... .... .... .... .... ..... .... .... .... .... ... 1
1.3 Classificationoftemporary waters .. .... .... .... .... .... ..... .... .... .... .... ... 3
1.4 Importanceoftemporary watersinthelandscape .. .... .... ..... .... .... .... .... ... 9
2 Thephysicalenvironment 12
2.1 Hydrological considerations.. ..... .... .... .... .... .... ..... .... .... .... .... .. 12
2.2 Origins:basinandchannelformation.... .... .... .... .... ..... .... .... .... .... .. 18
2.3 Climate,seasonality,andhabitatpersistence... .... .... .... ..... .... .... .... .... .. 21
3 Influentialenvironmental factors 25
3.1 Introduction .. .... .... .... ..... .... .... .... .... .... ..... .... .... .... .... .. 25
3.2 Waterbalance. .... .... .... ..... .... .... .... .... .... ..... .... .... .... .... .. 25
3.3 Watertemperatureandturbidity ... .... .... .... .... .... ..... .... .... .... .... .. 30
3.4 Dissolvedoxygenandcarbondioxide ... .... .... .... .... ..... .... .... .... .... .. 32
3.5 Otherchemicalparameters... ..... .... .... .... .... .... ..... .... .... .... .... .. 33
3.6 Substrate. .... .... .... .... ..... .... .... .... .... .... ..... .... .... .... .... .. 35
3.7 Light.... .... .... .... .... ..... .... .... .... .... .... ..... .... .... .... .... .. 36
3.8 Biologicalfactors. .. .... .... ..... .... .... .... .... .... ..... .... .... .... .... .. 37
4 Thebiota 40
4.1 Introduction .. .... .... .... ..... .... .... .... .... .... ..... .... .... .... .... .. 40
4.2 Taxa .... .... .... .... .... ..... .... .... .... .... .... ..... .... .... .... .... .. 40
4.3 Thetemporary watercommunity—globalscalecomparisons .. ..... .... .... .... .... .. 85
4.4 Thetemporary watercommunity—localscalecomparisons ... ..... .... .... .... .... .. 93
CaseHistories—Intermittent Waters.. .... .... .... .... ..... .... .... .... .... .... . 93
CaseHistories—Episodic Waters .... .... .... .... .... ..... .... .... .... .... .... . 108
4.5 Globalcommonalityamongcommunities. .... .... .... .... ..... .... .... .... .... .. 114
4.6 Permanentversustemporary waterfaunas.... .... .... .... ..... .... .... .... .... .. 116
4.7 Insectsversus crustaceansversus‘therest’.... .... .... .... ..... .... .... .... .... .. 119
5 Populationdynamics 121
5.1 Introduction .. .... .... .... ..... .... .... .... .... .... ..... .... .... .... .... . 121
5.2 Seasonalityandvariabilityinlifecycles .. .... .... .... .... ..... .... .... .... .... . 123
5.3 Phenotypicandgenotypicvariation . .... .... .... .... .... ..... .... .... .... .... . 130
5.4 Physiologyofdesiccation .... ..... .... .... .... .... .... ..... .... .... .... .... . 134
ix
x CONTENTS
5.5 Adaptations .... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 137
5.6 Adaptive‘strategies’ofcolonizingorganisms.... .... .... .... .... .... ..... .... .. 150
5.7 Activecolonization... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 151
5.8 Passivecolonization .. .... .... .... .... ..... .... .... .... .... .... ..... .... .. 159
6 Communitydynamics 163
6.1 Introduction .... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 163
6.2 Communitysuccession.... .... .... .... ..... .... .... .... .... .... ..... .... .. 166
6.3 Colonizationandcompetition... .... .... ..... .... .... .... .... .... ..... .... .. 168
6.4 Temporarywatersasislandsintimeandspace .. .... .... .... .... .... ..... .... .. 172
6.5 Trophic relationships.. .... .... .... .... ..... .... .... .... .... .... ..... .... .. 175
7 Othertemporarywater habitats 187
7.1 Introduction .... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 187
7.2 Phytotelmata.... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 188
7.3 Gastrotelmata ... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 203
7.4 Anthrotelmata... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 203
7.5 Snowfields ..... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 204
7.6 Marinelittoral pools.. .... .... .... .... ..... .... .... .... .... .... ..... .... .. 205
7.7 Reservoirs. ..... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 209
7.8 Deserts ... ..... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 209
7.9 Starfishes . ..... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 211
7.10 Dung .... ..... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 211
7.11 Commonalityamongpopulationsandcommunities... .... .... .... .... ..... .... .. 214
8 Applied aspectsoftemporarywaters 215
8.1 Introduction .... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 215
8.2 Aquaculture/agriculturerotation—anancientart. .... .... .... .... .... ..... .... .. 215
8.3 Floodplains andfisheries .. .... .... .... ..... .... .... .... .... .... ..... .... .. 217
8.4 Ricepaddyfields .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 226
9 Habitatsforvectorsofdisease 230
9.1 Introduction .... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 230
9.2 Whytemporary waters? ... .... .... .... ..... .... .... .... .... .... ..... .... .. 230
9.3 Temporarywater-facilitated diseases—who arethevectors?. .... .... .... ..... .... .. 230
9.4 Economic andhumanitarian costs.... .... ..... .... .... .... .... .... ..... .... .. 236
9.5 Eradicationvscontrol:vectorvshabitat... ..... .... .... .... .... .... ..... .... .. 238
9.6 Conclusions .... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 247
10 Importance andstewardship oftemporary waters 248
10.1 Introduction .... .... .... .... .... .... ..... .... .... .... .... .... ..... .... .. 248
10.2 Roleinthenaturalenvironment. .... .... ..... .... .... .... .... .... ..... .... .. 248
10.3 Management andconservation.. .... .... ..... .... .... .... .... .... ..... .... .. 253
10.4 Triumphs,failures,and‘works inprogress’ ..... .... .... .... .... .... ..... .... .. 263
10.5 Conclusions andrecommendations... .... ..... .... .... .... .... .... ..... .... .. 266
References 269
Index 315
CHAPTER 1
Introduction
1.1 What are temporary waters? considerableattentionelsewhere(e.g.W.D.Williams
1981; Hammer 1986; International Society for Salt
Wehaveshorttimetostay,asyou,
Lake Research 2001). Coastal marine habitats, for
WehaveasshortaSpring,
example salt marsh ponds and supralittoral rock-
Asquickagrowthtomeetdecay,
Asyouoranything pools,arealsosubjecttodrying,andwillbetouched
oninthisvolume.
(RobertHerrick,1591–1674)
The physicochemical features of temporary
Temporary waters, in general, are to be found waters strongly influence the biotas present, but
throughout the world. Some types, such as the biologicalfactorsmaybeimportantalsoespecially
reservoirs of bromeliad leaf axils and turloughs with increased duration of the aquatic phase.
(seasonallimestonelakes),arerestrictedbyfactors Insects and crustaceans tend to dominate the
such as climate or geology. Others, such as tem- fauna, but temporary water communities, as a
porary ponds and streams, and rain pools are whole,maycomprisebacteria,protoctists,vertebr-
ubiquitous—althoughthese,too,mayexhibitsome ates,fungi,andanabundanceofhigherandlower
regional differences (e.g. rain pools characterize plants. Many species exhibit opportunistic and
the high, open grasslands of South Africa). How- pioneering traits, and also a range of drought-
ever, all are, for the most part, natural bodies of survival mechanisms, such as diapause and seed
water which experience a recurrent dry phase. formation.
Often, the latter is predictable both in its time of Whereas wetlands, in general, comprise a very
onset and duration. The defining element is the important subset of temporary waters, and data
cyclical nature of the drought, as some permanent fromtheirstudywillbedrawnonthroughoutthis
waterbodies may dry up in exceptional years. In book,thelatterisnotintendedasacomprehensive
the latter case, because most of the biota is not synthesis of wetland biology per se. For such
adapted to survive such conditions there will be information the reader is directed to, for example:
significant mortality. Temporary water species,on Williams (1993), Finlayson and Van der Valk
the other hand, are generally well adapted to (1995), Mitsch and Gosselink (2000), Spray and
dealing with water loss. Indeed, many species McGlothlin (2004), and the websites of organiza-
have spread beyond the boundaries of natural tionssuchastheRamsarConventiononWetlands
waterbodies to colonize those temporary waters (http://www.ramsar.org/), and Wetlands Inter-
that have been created by human culture, such as national (http://www.wetlands.org/).
bird baths, and rainwater-filled tin-cans and tyre
tracks. Although the contents of this book are
1.2 Biological importance
devoted largely to temporary fresh waters, it is
important to remember that a great number of Despite perhaps being regarded as the cinderellas
inlandsalinewatersalsoexperiencedrought.Such of aquatic science, temporary waters represent
habitats are widespread and they have received significant components of the global landscape.
1
2 THE BIOLOGY OF TEMPORARY WATERS
From a cultural perspective, cyclically fluctuating of the ‘permanent’ biota that developed adapta-
water levels often have determined the sustain- tions to resist desiccation and good powers of
abilityandevolutionofripariansocieties.Aprime dispersal (Wiggins et al. 1980). The alternative
example is the annual flooding of the River Nile viewpoint considers most permanent lakes to be
upon which the agricultural activities of both geologically ephemeral (few are older than 20,000
ancient and modern civilizations have depended. years) and regards temporary water bodies as
Further,fromaresourceperspective,wetlands,for being very ancient, not as individuals but as a
example, represent a significant store of our pla- habitat type. Williams cited Lake George, a tem-
net’sfreshwaters.However,temporarywatersalso porary freshwater lake near Canberra, Australia,
have considerable significance to Biology per se. asbeing10millionyearsold.Hehypothesizedthat
Blaustein and Schwartz (2001) outlined four rea- fromriversandtheterrestrialenvironment,alarge
sons for studying temporary pools, specifically, contingent of the biota first colonized temporary
but which well encompass other temporary water freshwaters (perhapstemporary floodplain pools),
types: (1) temporary waters can contribute to our andthatasubsetofthisfloraandfaunadeveloped,
general understanding of ‘ephemerality’, espe- or regained, the ability to withstand permanent
cially as it relates to life histories, population inundation and hence were subsequently able to
dynamics, and community organization; (2) these establish themselves in permanent lakes. Under
habitats represent convenient systems in which to such a scenario, Williams stated that one would
study ecological concepts, particularly as they are expecttoseesomeofthefollowingproperties:the
amenable to manipulation experiments, and their more evolutionary ancient groups of the biota
abundance allows easy replication. Further, those should occur in temporary waters; much of the
habitats with simple communities can be mim- biota living in permanent waters should retain
icked in semi-natural or even artificial set-ups; effective dispersal mechanisms—to counter the
(3)temporarywatersfrequentlyharbourthevectors geological ephemerality of their habitats and as a
of disease-causing organisms that afflict mankind; reflection of their lineage; many of the ‘active
and (4) temporary waters contain many species migrants’ of the permanent lentic biota, should
important to global biodiversity. persist in lotic habitats, or have close relatives
To these may be added: (5) that, in a biogeo- which do; and overall species richness in tempor-
graphicalcontext,thereisevidencetosuggestthat ary waters should be greater than in permanent
temporary ponds may have acted as postglacial freshwaters.Evidencefromtheliteratureprovides
dispersal routes for taxa possessing dormant some support for each of these properties (Tasch
stages capable of ‘island-hopping’ (e.g. copepods) 1969; Elgmork 1980; Fernando 1980; Schram 1986;
from glacial refugia (Stemberger 1995); (6) in an Fernando and Holc´ık 1989; Lake et al. 1988);
evolutionarycontext,therehasbeenexplorationof (7)withincreasinginterestinland-waterecotones,
the ideathatlifemayhaveevolved onearthmore themarginsoftemporarypondsandstreamshave
thanonce,andthatanalternativeenvironment-of- the potential to be important sites for modelling
origintotheoceansmayhavebeenpondsthatdry hydrological processes, nutrient transport and
out periodically. In such ponds, chemicals in transformation, and the role played by the biota
solution would have been progressively con- (BradleyandBrown1997;GiudicelliandBournard
centrated to a state that enabled the maintenance 1997); and (8) there is now evidence to indicate
of protoplasmic systems (Hinton 1968). Further, that variations in the physical environment of
W.D. Williams (1988) has suggested that there is inlandwatersimpactbothmolecularandmorpho-
an alternative explanation to the hypothesis that logical evolution by changing mutation rates
thebiotaofpermanent,standingfreshwaterscame and by exposing (through genotype–environment
from marine ancestors via either the terrestrial interactions) otherwise cryptic variation. Extreme
environment, rivers or estuaries, and which releg- environments tend to accelerate morphological
atesthebiotaoftemporaryfreshwaterstoasubset change, promoting diversification (Hebert 1999).
INTRODUCTION 3
Temporary waters may be important sites of such Lengthandintensityofthedryperiodalsohave
alteredratesofmolecularevolutionand,therefore, been suggested as criteria, and may be more bio-
worth further study. logically relevant. Length of the dry phase can be
divided simply into seasonal, annual, and greater
thanannual—butcyclical.Intensityofthedrought
1.3 Classification of temporary waters is important because, for example, two habitats
which both remain dry for 4 months of the year
1.3.1 Review of some previous classification
might have different moisture-retaining capacities
schemes
of their substrates, allowing the survival of sig-
Temporary waters are amazingly diverse in the nificantly different biotas. Climatologists have
habitatsthattheypresentforthedevelopmentand deriveda numberofindices for droughtthatmay
sustainmentoflife.Bywayofanexample,Table1.1 haveusefulapplication totemporary waters.One,
lists the main types of temporary standing waters widely used example is the Palmer Hydrologic
tobefoundintheBritishIsles.Itsubdividesthese Drought Index, which combines precipitation
habitats into those of natural origin (e.g. peatland and temperature values with soil water content
poolsandcupfungi;Figure1.1)andthoseresulting data—including outflow and storage measures
fromhumanactivities(e.g.quarrypondsandsaw- (Heddinghaus and Sabol 1991). Some researchers
pit ponds), and also distinguishes common from have found significant correlations between this
rarer,orregional,types.Includinglotictemporary index and temporary water invertebrate popula-
waters would swell the list considerably. Faced tion dynamics (Hershey et al. 1999).
withsuchaninventory,itisperhapslittlewonder As with all systems of classification, there are
that classification attempts for temporary waters boundtobeexceptionswhichdonotfitanyofthe
are few and far between. One proposal has been categories, for example, Lake Eyre in southern
baseduponhabitatsize(micro-,meso-,andmacro-; Australia only fills with water every half century
Table1.2)butthistendstolumphabitatsthatmay or so (Mawson 1950). Can this really be called
support quite different communities, for example cyclical? The majority of species that would col-
lowland,floodplainpoolsandalpinelakes. onizesuchalakewoulddiewhenitdriedup,with
Table1.1 ThemaintypesoftemporarystandingwaterfoundinBritain
Naturalorigin
Commontypes:Intermittentandepisodic(‘seasonal’)ponds,lakes;marginsofpermanentpondsandlakes;floodplainponds;oxbowponds;
deltaicponds;tidalwetlands;supralittoraltidepools;peatlandpools;woodlandpools;vernalponds(filledonlyinspring);autumnalponds
(summer-dry);rainpools(bothinclaysoilsandcrevicesinbedrock);poolsassociatedwithuprootedtreesandlandsurfaceundulations;
emptysnailshells;water-filledhoof-prints;liquiddung.
Rarerand/orregionaltypes:Pondsassociatedwithglacialactivities(e.g.kettleponds,formedbysubsidenceresultingfrommeltingof
subsurfaceice,andmoraineponds,formedinglaciallydepositedsediments),solutionofbedrock,andironpans;turloughs(water-filled
depressionsunderlainbylimestone);plungepools(formedatthebaseofdried-upwaterfalls);waterretainedbycupfungi,teasels
andmosses;treeholes;waterretainedinlargeleafaxils.
Humanorigin
Quarrypools;poolsassociatedwithminingandlandscaping;wheel-rutpools;cattle-wateringpondsandtroughs;poolsresultingfrom
peat-digging;waterfowl-decoychannels;fishponds;pondsassociatedwithancientruralactivities(e.g.dewponds,rainwater-collectionponds,
armed/water-distributionponds,saw-pitponds,charcoal-burningpits);depressionsassociatedwithdefenceandwarfare(e.g.ditches,
trenches,moats,bombcraters);rain-filledtyresandplasticsheeting(e.g.silageyards);middenpools;rainbarrels;cisterns;ornamental
birdbaths;poolsassociatedwithlandfillsites;slurryvats;footprints;water-filled,cattle-trampleddepressions(e.g.aroundgatesand
feedingareas).
Source:InformationtakenfromRackham(1986)andWilliams(1987),wheregreaterdescriptionofthesevarioushabitatscanbefound.
4 THE BIOLOGY OF TEMPORARY WATERS
Figure1.1 Photographofarainfilledcupfungus;notetheaccumulatedparticlesofdetritusthatmayserveasfoodforthebiota,
andthepresenceofseveralsemi-aquaticoligochaetes.
Table1.2 Classificationoftemporarywaterhabitatsbasedonsize
Microhabitats:Axilsofplantleaves(e.g.bromeliads);treeholes;rain-filledrockpools;tincans;brokenbottlesandothercontainers;footprints;
tyretracks;cisterns;emptyshells(e.g.molluscsandcoconuts)
Mesohabitats:Temporarystreamsandponds;snow-meltpools;monsoonrainpools;floodplainpools;dewponds;wetlandpools
Macrohabitats:Periodicallyflooded,largeoldriverbeds;shallowoxbowlakes,dryinglakes,dryinglakeshores,alpinelakes;sloughs;turloughs
Source:AdaptedfromDecksbach(1929).
perhapsonlyafew,highlyspecializedformsbeing Clearly it contained at least one species normally
able to span the 50 or so years between fill ups. characterized as being indicative of temporary
TheoccurrenceofsomewaterbodiesintheUnited waters.
Kingdom affords another example of a misfit. Classifications based on indicator species, or
Triops(anotostracan,ortadpoleshrimp),wasfirst speciesgroupsalsoarenotinfallible.Forexample,
recorded in 1738 from a ‘temporary’ pond, it was Klimowicz (1959) attempted to classify small
next recorded in 1837 and again in 1948, after a ponds in Poland on the basis of their molluscan
lapse of 111 years (Schmitt 1971). Although it did faunas. Granted, some snail and bivalve species
notappear,naturally,duringallthattime,itcould are very resistant to water loss and may be use-
be hatched from dried mud taken from the pond fully assigned to different habitat types, however
and rehydrated. This animal requires a period of some, such as Musculium partumeium, are known
desiccation prior to hatching and the wet British to occur in both temporary and permanent ponds
climate did not create suitable conditions very (Way et al. 1980). Colless (1957) modified a clas-
often.Whethersuchapondcouldbetrulytermed sificationschemeofLaird’s(1956)basedonbreeding
‘temporary’,orwhetheritwassimplyapermanent habitatsformosquitoes.Init,hecreatedtwomain
pond that dried up infrequently is debatable. categories—Surface Water, and Containers—the