H2.1 ROCKY SHORE - Dalhousie University

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Habitats Natural History of Nova Scotia, Volume I

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© Nova Scotia Museum of Natural History

H2.1 ROCKY SHORE

H2.1Rocky Shore

Rocky shores are areas of bedrock exposed betweenthe extreme high and extreme low tide levelson the seashore.

Plate H2.1.1: Exposed rocky shore seen near low water, with a tidal pool in the foreground. In the background is a cobble shore, mouth of St. Marys River,Guysborough County (Unit 842). Photo: D.S. Davis

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Natural History of Nova Scotia, Volume I Habitats

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bedrock is commonly eroded into a wave-cutplatform with gentle slopes.

2. Wave action: exposure to wave action, relatedto dominant wind direction, storms and ocean-swell conditions, controls plant and animalattachment.

3. Tidal regime: tide range determines the area ofshore exposed to the air. There is considerableregional variation.

4. Climatic conditions: weather conditions includesummer and winter temperature extremes,humidity, precipitation and wind exposure.

FORMATION

Rocky shores form as a result of marine erosion ofthe overburden and the bedrock, due to a combina-tion of rising sea level and wave action, in areaswhere there is low sediment supply.

PHYSICAL ASPECTS

l. Bedrock: resistant bedrock, such as granite,slate and quartzite, erodes slowly and producessteep gradients. Less-resistant sedimentary

H2.1Rocky Shore

B: Sandy Shore

C: Salt Marsh

A: Rocky Shore

Figure H2.1.1:A comparison of intertidal zonation on three types ofshore on the Atlantic Coast of Nova Scotia. Horizontal distances are notto scale. EHW= Extreme-high-water mark. MTL= Midtide level.ELW= Extreme-low-water mark.

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ECOSYSTEM

The ecosystem is complex, as it is an interactionbetween terrestrial and aquatic systems. Energy sup-ply is obtained through primary production byseaweeds and phytoplankton and through organicdetritus derived from adjacent land and other in-tertidal habitats (e.g., tidal marshes). This energy isdirectly utilized by a variety of herbivorous and de-tritus-feeding animals on the shore, which are, intheir turn, preyed upon by several levels of carni-vore on the shore, by fish entering the habitat athigh tide and by terrestrial animals, particularlybirds, entering at low tide.

PLANTS

The plants are typically algae and lichens. In shel-tered or muddy locations where there is some sedi-ment accumulation amongst the rocks and in tidepools, Cord Grass and Eelgrass may also be found.The seaweeds and lichens are distributed on the shorein horizontal zones that relate to tolerance of thespecies to either exposure to air (seaweeds) or sub-mergence in water (lichens) during the tidal cycle.1

Conspicuous plants inhabit different zones:

Splash ZoneAbove the extreme-high-water mark but reachedby storm waves, the splash zone is generally bareof vegetation. There may be grasses growing incracks of rocks and some patches of lichens (e.g.,Xanthoria parietina).

Upper ShoreRocks bare at the top but, below the level of highwater of spring tides, the upper shore supportsalgae (e.g., Codiolum spp., Calothrix crustacea) andlichens (Verrucaria spp.)

Middle ShoreThe middle shore supports dense growth of brownrockweeds Ascophyllum nodosum and Fucus spp.The red seaweed Porphyra and Fucus serratus andgreen seaweeds, such as Cladophora spp., are com-mon in some places. The epiphytic Polysiphonialanosa can be found growing on the Ascophyllum.

Lower ShoreBelow the dense rockweeds on the lower shore, thereis a conspicuous zone of Irish Moss and calcareousalgae (Lithothamnium spp. and Corallina officinalis).

Below this, kelps (Laminaria spp.) are present butonly visible at low water of spring tides. This zonecontinues into the sub-littoral benthic habitat(H1.1).

The seaweed growth is usually well developedon all rocky shores but is best in exposed, clear-water conditions, such as on the Atlantic Coast (Re-gion 800 and Unit 911) and lower reaches of the Bayof Fundy (Unit 912). On the Northumberland Strait(Unit 914) and Inner Bay of Fundy (Unit 913), iceaction and turbidity limit seaweed growth.

ANIMALS

The animals include marine benthic epifauna tol-erant to various periods of exposure to the air at lowtide, and vagrant terrestrial species. A system of hori-zontal zonation of the aquatic fauna is apparent.

Upper ShoreOn the bare rock surfaces, there are very few ani-mals present, except the Rough Periwinkle.

Middle ShoreAt the top, there is a conspicuous zone of barnacles,which is limited at its lowest extent by the growth ofrockweed. There is a variety of herbivorous animals,including Rough Periwinkles, Smooth Periwinkles,Common Periwinkles and amphipod crustaceans.Sessile species include Hydroids (Sertularia spp.)and Blue Mussels. The Green Sea Urchin is found atlower levels. Carnivores which feed mainly on themolluscs include Dog Whelks and Purple Starfish.

Lower ShoreLower down the shore, the diversity of animals in-creases as more species are tolerant to the shorterperiod of exposure at low tide. This is particularlytrue where animals can find shelter under rocks orseaweeds. Herbivores include Common Periwinkles,Limpets, Green Sea Urchins, isopods and am-phipods. The sessile particulate feeders includesponges, hydroids, tube worms (Spirorbis spp. onseaweeds), Horse Mussels, brittle starfish andtunicates. The carnivores include Sea Anemones,Scale Worms, Purple Starfish, Rock Crabs and SeaSlugs. On sedimentary rocks of the Minas Basin andNorthumberland Strait, rock-boring bivalvesPetricola pholadiformis, Zirphaea crispata andBarnea truncata are locally important. Vagrant ter-restrial species, insects, birds and mammals enterthe rocky-shore habitat at low tide to feed. Severalshore-bird species feeding on rocky shores includeRuddy Turnstones; Herring Gulls are also typical.

H2.1Rocky Shore

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Associated TopicsT4 Colonization, T6.1 Ocean Currents, T6.2 Oce-anic Environments, T7.1 Modifying Forces, T7.2Coastal Environments, T7.3 Coastal Landforms,T10.9 Algae, T10.11 Lichens, T11.6 Shorebirdsand other Birds of Coastal Wetlands, T11.10 Ungu-lates, T11.12 Marine Mammals, T11.14 MarineFishes, T11.17 Marine Invertebrates

Associated HabitatsH1.1 Open Water, H1.2 Benthic, H2.2 Boulder/Cob-ble Shore, H2.3 Sandy Shore, H2.4 Mud Flat, H2.5Tidal Marsh, H5.3 Cliff and Bank

References1. MacFarlane, C.I. and G.M. Milligan (1966)

Marine Algae of the Maritime Provinces ofCanada. A preliminary checklist (MS). NovaScotia Research Foundation, Halifax.

Additional Reading• Bousfield, E.L. and D.R. Laubitz (1972) “Station

lists and new distributional records of littoralmarine invertebrates of the Canadian Atlanticand New England Regions”. In BiologicalOceanography, No. 5, National Museum ofCanada, 51.

• Davis, D.S. (1972) The Atlantic Shore. NovaScotia Museum, Halifax. (EnvironmentalStudies Series).

• Davis, D.S. (1972) The Fundy Shore. NovaScotia Museum, Halifax. (EnvironmentalStudies Series).

• Davis, D.S. (1972) The Northeast Cape BretonShore. Nova Scotia Museum, Halifax. (Environ-mental Studies Series).

• Davis, D.S. (1972) The Northumberland StraitShore. Nova Scotia Museum, Halifax. (Environ-mental Studies Series).

• Stephenson, T.A. and A. Stephenson (1954) “Lifebetween tidemarks in North America, III A, NovaScotia and Prince Edward Island: description ofthe region.” J. Ecology 42.

• Tufts, R.W. (1986) The Birds of Nova Scotia, 3rded. Nova Scotia Museum, Halifax.

(Sea urchins found the above high-water mark pro-vide evidence of gull feeding.)

Rocky-shore habitats are important feedinggrounds for White-tailed Deer in winter. There is aregular occurrence of deer eating kelp along theAtlantic coast east of Halifax, through to Louisbourg.

SPECIAL FEATURES

• The local modification of plant and animalzonation relates to the tide range, exposure, iceaction and other environmental factors.Considerable regional variation is seen. FigureH2.1.1 shows some examples of zonation.

• Tide Pools: Where water is retained in depres-sions or cracks in the bedrock during the low-tide period, the plants and animals are notsubjected to dessication. As a result, these poolsoften exhibit rich growths of organisms nor-mally associated with the lower shore andsubtidal habitats. Large pools are not stronglyinfluenced by air temperatures, but smallerpools, particularly if located at high levels onthe shore where they may not be flushed out byneap tides, experience wide ranges of tempera-ture and salinity. In these conditions, onlyhardy algal species, such as Enteromorphaintestinalis, can occur.

DISTRIBUTION IN NOVA SCOTIA

Rocky shores occur all around the coast of NovaScotia but vary in their character according to thephysical aspects that prevail. Rocky shores in theInner Bay of Fundy (Unit 913) are strongly influ-enced by mud and ice action and have poor sea-weed growth. Different examples of rocky shorescan be seen in the wave-cut platform in the basaltbedrock in the Outer Bay of Fundy (Unit 912). Thegranite and quartzite headlands of the Atlantic Coast(Region 800) form another type of rocky-shore habi-tat. In Cape Breton and the Northumberland Strait(Unit 914), soft sedimentary rocks, small tide rangeand winter ice action result in relatively poor rocky-shore development. There is no intertidal zone inthe Bras d’Or Lake (District 560 and Unit 916).

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H2.1Rocky Shore

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H2.2 BOULDER/COBBLE SHORE

FORMATION

Boulder/cobble shores form where there is erosionof glacial till on headlands and islands. In high-energy situations, the cobbles may form a stormbeach at and above the high-tide mark. In interme-diate- and low-energy situations, the boulders reston a wave-cut platform.

PHYSICAL ASPECTS

l. Substrate: boulders provide a relatively stablehard substrate. Cobbles and pebbles are usuallymobile.

2. Wave action: in high-energy situations, expo-sure to wave action, related to dominant winddirection, storms and ocean-swell conditions,the boulders and cobbles are mobile, limitingcolonization by intertidal organisms.

3. Tidal regime: tide range determines the area ofshore that is exposed to the air.

4. Water–land interaction: water conditions includesummer and winter temperature extremes, for-mation and movement of ice, and variations inturbidity and salinity.

5. Climatic conditions: air conditions include sum-mer and winter temperature extremes, humid-ity, precipitation and wind exposure.

H2.2Boulder,Cobble Shore

Boulder/cobble-shore habitats are exposed betweenthe extreme-high-tide and extreme-low-tide marks.

Plate H2.2.1: An example of a cobble-shore habitat at Cape Sable Island (Unit 841), Shelburne County Photo: A. Wilson

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© Nova Scotia Museum of Natural History Natural History of Nova Scotia, Volume I Habitats

wave action, the cobbles are more stable andbecome colonized by encrusting lichens andflowering plants, such as Sea-lungwort andBeach Pea. Animal life is limited to variousspecies of amphipods and fly larvae, whichfeed on decaying seaweed cast up by storms.Spiders and birds prey upon these animals.


Boulder/cobble-shores are found along the wholeNova Scotia coastline but are best developed alongthe Atlantic coast where there is sufficient glacialtill source material. In St. Margarets Bay andMahone Bay (District 460), for example, erodingdrumlins have boulder and cobble beaches withvarying degrees of exposure. The islands eventu-ally erode away to leave boulder reefs visible onlyat low tide. Sheltered boulder beaches occur at thehead of inlets, such as in Head Harbour (sub-Dis-trict 460b).

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Associated TopicsT6.1 Ocean Currents, T6.2 Oceanic Environments,T7.1 Modifying Forces, T7.2 Coastal Environments,T7.3 Coastal Landforms, T10.9 Algae, T10.11 Li-chens, T11.6 Shorebirds and other Birds of CoastalWetlands, T12.7 The Coast and Resources

Associated HabitatsH1.1 Open Water, H1.2 Benthic, H2.1 Rocky Shore,H2.3 Sandy Shore, H2.4 Mud Flat, H2.5 Tidal Marsh,H2.6 Dune System, H5.1 Barren, H5.3 Cliff and Bank

Additional Reading• Davis, D.S. (1972) The Atlantic Shore. Nova

Scotia Museum, Halifax. (EnvironmentalStudies Series).




• Stephenson, T.A. and A. Stephenson (1954) “Lifebetween tidemarks in North America, III A,Nova Scotia and Prince Edward Island: descrip-tion of the region.” J. Ecology 42.

ECOSYSTEM

Primary production within the habitat is limited tothe seaweed growth, which is very limited or absentin exposed situations. Energy also enters the sys-tem through primary production in the plankton,and through suspended organic detritus derivedfrom the land and adjacent intertidal habitats. Thereare herbivores and detritus-feeders in the epifauna,but populations are often small. These animals arepreyed upon by carnivores, including birds.

PLANTS

Mainly algae (seaweeds) colonize the surfaces ofboulders. In intermediate- and low-energy situa-tions, there is horizontal zonation related to theperiod of exposure at low tide.

Upper ShoreOn the upper shore, where the cobbles are easilymoved by wave action, there is no seaweed growth,but some lichens and flowering plants occur abovethe high-tide mark.

Middle ShoreOn the middle shore, in sheltered conditions, thereis a narrow black band of algae and lichens belowwhich brown seaweeds, Fucus spp. and Ascophyllumnodosum, are conspicuous. Various filamentousalgae are present in the spring. Cord Grass may befound growing in mud and gravel between the boul-ders at lower levels. In more exposed situations, theseaweed growth is limited by the movement of theboulders and cobbles. Where seaweeds do occur,there is usually a sparse growth of the brownseaweeds, with Irish Moss and the calcareousspecies Corallina officinalis and Lithothamniumspp. growing in the lower zone.

ANIMALS

The movement of boulders and cobbles in high-en-ergy situations severely limits colonization by animals.In low and intermediate energy situations, barnacles,isopods, amphipods, periwinkles, Green Crabs, DogWhelks, Blue Mussels and Purple Starfish are oftenpresent.

SPECIAL FEATURES

• On exposed, high-energy shores, the cobblesare often washed up to form a storm beach orberm. As they are largely beyond the reach of

H2.2Boulder

Cobble Shore

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H2.3 SANDY SHORE

H2.3Sandy Shore

Sandy-shore habitats are areas of sand exposedbetween the extreme-high-tide and extreme-low-tidemarks.

Plate H2.3.1: A sandy shore at Caribou Island, Pictou County (sub-Unit 521a). In the background is a sea cliff (H5.3) and rocky shore (H2.1).Photo: R. Merrick

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FORMATION

Sandy shores form through the deposition of sandresulting from the erosion of glacial till and bed-rock in the area of occurrence.

PHYSICAL ASPECTS

l. Substrate: the substrate includes particle sizesranging from fine gravel to sandy mud. In shel-tered conditions the mud content increases andreduced drainage results in anaerobic conditionsjust below the surface. In exposed conditionsthe sand is often mobile, well-drained and well-aerated.

2. Wave action: exposure to wave action, related todominant wind direction, storm and ocean-swellconditions, and influence of tidal and alongshorecurrents affects the mobility of the sand.

3. Tidal regime: tidal range determines the area ofshore that is exposed to the air.

4. Water–land interaction: water conditions in-clude summer and winter temperature extremes,formation and movement of ice, turbidity andsalinity.

5. Climatic conditions: air conditions include sum-mer and winter temperature extremes, humid-ity, precipitation and wind.

Figure H2.1.1 compares intertidal zonation of asandy shore with a rocky shore and a salt marsh.

ECOSYSTEM

There is no significant primary production, exceptby blue-green algae and diatoms that occur on thesurface of sandy mud in sheltered conditions. En-ergy input into the system is from the phyto-plankton in the water and from particulate organicmatter (detritus) derived from the land and adja-cent intertidal habitats. Herbivorous and detritus-feeding and carnivorous animals are included inthe sand infauna. Carnivores include vagrant fishand birds.

PLANTS

Due to the mobility of the substrate, plant life isvery limited in both diversity and abundance.Seaweeds are mostly absent, but diatoms and blue-green algae may be common in sheltered, sandy-mud conditions. Ulva and Enteromorpha developin summer on many sandy-mud flats. Also, in theseconditions, some Cord Grass and Glasswort mayoccur as a first stage in tidal-marsh succession. On

exposed shores, wind-blown sand accumulatesabove the high-water mark as dunes, and pioneerbeach plants, such as American Beach Grass andSea-rocket, may occasionally be subjected to wavesor spray.

ANIMALS

The absence of hard substrate results in the pre-dominance of infaunal species. Distribution andabundance are controlled largely by the tide leveland mobility of the sand. At low-tide levels, the sandseldom dries out, but is mobile due to currents andwave action. Animals have to burrow to maintaintheir position on the beach. On exposed beaches,polychaete worms (Dispio uncinata, Nephtysbucera) and molluscs (Tellina agilis, Spisulasolidissima, Ensis directus and Lunatia heros) oc-cur at low-tide level. Isopod and amphipod crusta-ceans (Chiridotea caeca, Haustorius canadensis)also occur at the mid- and low-tide levels. At thehigh-tide mark, amphipods (Talorchestia spp.) arecommon, feeding on organic matter in the drift line,and overlap in their occurrence with insects, in-cluding the larvae of flies and beetles. Where thesand grades into sandy mud in sheltered condi-tions, the fauna increases in both diversity andabundance. Ribbon worms (Cerebratulus spp.),polychaetes (Nereis spp. and Nephtys spp.), bivalves(Mya arenaria, Macoma balthica) and mud snails(Nassarius, Ilyanassa) are typical. Where patchesof gravel occur on the lower shore, clumps of BlueMussels are found with associated barnacles andother epifauna. Sandy shores provide importantfeeding grounds for a variety of shore birds, includ-ing sandpipers and plovers. Flounders and otherfish come in to feed at high tide.

SPECIAL FEATURES

• There is usually seasonal variation in thedistribution of sand on the shore, due to windand wave action. Sand is transferred from thebeach to shallow water in the winter and isreturned in the summer. This mobile sand canbuild up as well-drained bars that dry out at lowtide and which support few animals.

• Sand shores are the best localities for beach-combing and shell collecting during thesummer. Because of the on-shore movement ofsand, it is possible to find shells of species thatlive offshore.

H2.3Sandy Shore

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Distribution of sandy shores follows the wholecoastline of Nova Scotia, with best developmentalong the Atlantic and Northumberland Straitcoasts and the Minas Basin.

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Associated TopicsT6.1 Ocean Currents, T6.2 Oceanic Environments,T7.1 Modifying Forces, T7.2 Coastal Environments,T7.3 Coastal Landforms, T10.5 Seed-bearing Plants,T10.9 Algae, T11.6 Shorebirds and Other Birds ofCoastal Wetlands, T11.17 Marine Invertebrates

Associated HabitatsH1.1 Open Water, H1.2 Benthic, H2.1 Rocky Shore,H2.2 Boulder/Cobble Shore, H2.4 Mud Flat, H2.5Tidal Marsh, H2.6 Dune System

Additional Reading• Davis, D.S. (1972) The Atlantic Shore. Nova

Scotia Museum, Halifax. (EnvironmentalStudies Series).




• Tufts, R.W. (1986) The Birds of Nova Scotia, 3rded. Nova Scotia Museum, Halifax.

H2.3Sandy Shore

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H2.4 MUD FLAT

H2.4Mud Flat

Mud-flat habitats are areas of mud and sandy mudexposed between the extreme-high-tide and extremelow-tide marks.

Plate H2.4.1: Mud flat, with mussel shells and stones colonized by Fucus in the foreground. The forest is coastal spruce, fir–maple, birch association (H6.3).Sandy Cove, (St. Marys Bay), Digby County (District 810). Photo: R. Merrick.

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FORMATION

Mud flats form from the deposition of mud insheltered tidal water, particularly in estuaries wherethere is a large sediment supply.

PHYSICAL ASPECTS

l. Substrate: particles range from fine sand to silt,and are often compacted into clay. Drainage ispoor, and anaerobic conditions exist just belowthe sediment surface.

2. Wave action: the surface sediment is mobile inmoderate waves, due to exposure to waveaction, related to wind and to a tidal andlongshore currents.

3. Tidal regime: tidal range determines the area ofshore that is exposed to the air.

4. Water–land interaction: water conditionsinclude summer and winter temperatureextremes, formation and movement of ice,turbidity and salinity.

5. Climatic conditions: air conditions includesummer and winter temperature extremes,humidity, precipitation and wind.

ECOSYSTEM

Primary production is limited to diatoms and othermicroscopic and filamentous algae and to CordGrass. Most energy enters the system from the plank-ton, or as organic detritus derived from the land oradjacent tidal marshes. The detritus and associatedbacteria are consumed by large populations of bi-valve molluscs, amphipods and polychaetes. Theseare, in turn, eaten by carnivores, and particularly bymigratory shore birds. The crustacean Corophiumvolutator occurs in the Bay of Fundy intertidal mudflats (Units 912, 913) and is an important food sourcefor the migratory Semipalmated Sandpiper (seeT11.6).

PLANTS

Plants are limited to microscopic algae (diatoms)and filamentous algae on the sediment surface, andoccasionally seaweeds, such as Fucus spp., attachedto stones. Some Cord Grass is found at the firststage of tidal-marsh succession, and Eel Grass oc-curs on the lower shore.

SUCCESSIONAL SEQUENCE

1. In sheltered areas, the deposition of sedimenton the shore will eventually raise the level sothat seeded or ice-transported Cord Grass maybecome established.

2. The Cord Grass expands from the point ofcolonization by vegetative means and acceler-ates the rate of sediment deposition, develop-ing into the low marsh (see H2.5).

3. When the substrate of the marsh rises to themean-high-water mark through the accumula-tion of sediment, the Cord Grass gives way toMarsh Hay and associated plants, and the highmarsh develops (see H2.5).

4. With further sediment deposition, thevegetation becomes mainly freshwater: cattail,rushes and reeds, possibly in association withspruce (swamp).

ANIMALS

Animals are predominantly detritus-feeding infaunathat can tolerate exposure at low tide and the me-chanical difficulties of living in mud. Polychaeteworms (Spiophanes wigleyi, Clymenella torquata),amphipods (Corophium volutator) and bivalves(Mya arenaria, Macoma balthica) are particularlycommon. Scavengers and carnivores present arepolychaetes (Neanthes virens), crustaceans(Chiridotea caeca, Crangon septemspinosus) andmolluscs (Ilyanassa obsoletus, Lunatia heros).

Sessile epifauna species, such as barnacles andSlipper Limpets, occur attached to small stones ly-ing on the mud surface. Flounders and other fishspecies come on to the mud flats to feed at hightide. Mud flats are also important feeding areas formigratory shore birds, such as the SemipalmatedSandpiper, and land mammals (particularly Rac-coons).

SPECIAL FEATURES

• Vast numbers of a few species of infaunadepend on a diet of organic detritus. Examplesof population densities are 15 000/m2 forCorophium volutator and 3500/m2 for Macomabalthica. These animal populations supportlarge flocks of migrating shore birds during thelate summer. This habitat is critical to thesurvival of the Semipalmated Sandpiper. Flockstotalling over 280,000 gather at the Head of theBay of Fundy to feed before continuing theirmigration south. This is an important ecological

H2.4Mud Flat

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feature of Nova Scotia. Migratory fish also visitto feed on the benthic (e.g., Corophium) andepibenthic species (e.g., Neomysis, Mysis,Crangon).


Mud flats occur in all inlets and estuaries aroundthe coast of Nova Scotia, but the best examples arein Minas Basin, Cobequid Bay (sub-Unit 913a) andCumberland Basin (sub-Unit 913b).

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Associated TopicsT6.1 Ocean Currents, T6.2 Oceanic Environments,T6.3 Coastal Aquatic Environments, T6.4 Estuar-ies, T7.2 Coastal Environments, T7.3 CoastalLandforms, T10.5 Seed-bearing Plants, T10.9 Al-gae, T11.6 Shorebirds and other Birds of CoastalWetlands, T11.12 Marine Mammals, T11.14 Ma-rine Fishes, T11.17 Marine Invertebrates, T12.7 TheCoast and Resources

Associated HabitatsH1.1 Open Water, H1.2 Benthic, H2.1 Rocky Shore,H2.2 Boulder/Cobble Shore, H2.3 Sandy Shore,H2.5 Tidal Marsh

Additional Reading• Risk, M.J., R.K. Yeo and H.D. Craig (1977)

“Aspects of marine ecology of the Minas Basinrelevant to tidal power development.” In G.R.Daborn, ed., Fundy Tidal Power and theEnvironment. Acadia University Institute,Wolfville. (Publication No. 28). pp. 164–179.

H2.4Mud Flat

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H2.5 TIDAL MARSH

H2.5Tidal Marsh

Two types of tidal marsh occur in Nova Scotia: saltmarshes and coastal fresh marshes. Both are marineintertidal areas with soft substrate, colonized

predominantly by grasses. They occur only wherethere is regular flooding and nearby sources of finesediment.

Plate H2.5.1: Salt marsh showing Cord Grass (Spartina alterniflora), St. Marys River, Guysborough County (Unit 842). The surface water of the tidal estuaryis almost always fresh. Photo: D.S. Davis

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3. Relief: tidal marshes have low relief and are gen-erally flat with a gradual slope deeply cut bydrainage channels. In some areas, deep, straight-sided and permanent ponds, or pannes, are acommon feature.

4. Drainage: drainage in tidal marshes is generallypoor, due to the nature of the soil, which is atleast partly covered by each flood tide and bysurface runoff. There is often standing water indepressions. Salt marshes typically have net-works of channels that drain tidal water.

5. Physical regime: although they get their namefrom the twice-daily inundation of seawater, tidalmarshes are typically exposed to varying degreesof salinity. The higher parts of the marsh formthe most landward extreme of the marine envi-ronment, reached only by very high tides orstorm surges. Here, plants are exposed togroundwater and freshwater runoff and, typically,to low salinities. Seaward, the salinities of watercovering the marsh rarely reach full strength, buton an exposed marsh, the sediments’ salinity canreach ten times the salinity of the ocean as aresult of evaporation. Figure H2.1.1 comparesintertidal zonation of a salt marsh to a rocky anda sandy shore.

ECOSYSTEM

Salt marshes are among the most productive eco-systems in the world; however, Nova Scotia marshesare less productive than some of the extensive saltmarshes found along the Atlantic coast of the UnitedStates and into the Gulf of Mexico.3 Much of theproductivity of the Nova Scotia salt marshes leavesthe marsh as detritus from Cord Grasses (Spartinaspp.) and becomes a food source for marine foodchains. At the head of the Bay of Fundy (Unit 913),the marshes provide the principal food source formarine organisms, which support vertebrates, suchas fish and shorebirds.

Soils and seawater inundation provide limitednutrients for growth of salt-marsh plants. Nitrogencomes from nitrogen-fixing bacteria found in thesoils and from the films of blue-green algae growingon the surface of salt-marsh muds.

Small fish, birds (which includes the Great BlueHeron, various waterfowl, shorebirds and songbirds),and a variety of small mammals, insects and marineinvertebrates are found in salt marshes.

Coastal fresh marshes are also highly productivesystems with abundant nutrients. The primary pro-duction is largely carried out by grasses, sedges andrushes, and is either consumed or accumulates on

FORMATION

Salt marshes form on stable or emerging coastlineswhen sediment accumulates in sheltered intertidalareas in estuaries, behind spits, bars or islands, andin protected bays. Cord Grass colonization acceler-ates the accumulation of sediment and helps todevelop conditions suitable to further marsh devel-opment. In Nova Scotia, where coastlines are sub-merging at a slow rate, marshes form when the rateof sedimentation exceeds the rate of submergence.

Coastal fresh marshes form when the effect ofsalt water on the low-lying coast is moderated byfreshwater runoff. Where this occurs, the salt-toler-ant plants of the intertidal zone give way to non-tolerant species, even though there may be asemidiurnal tide (upper reaches of estuaries) or oc-casional tidal flooding (low-lying areas behind saltmarshes).

The upper limit of the tidal marsh is the highesthigh water, and the lower limit is mean sea level. Inthe Bay of Fundy (Units 912, 913), where the tidalrange is most extreme (about 15 m), the marsh veg-etation extends only to an elevation of about 4 mbelow high water.1

PHYSICAL ASPECTS

1. Bedrock: bedrock is not significant, as it is usu-ally deeply buried beneath the marsh soil; how-ever, soft bedrock in the general area (e.g.,sandstones in Bay of Fundy [District 620 andUnit 913] and Northumberland Strait [District530 and Unit 914]) may contribute to the sedi-ment supply necessary for marsh construction.On the Atlantic coast, most sediment is derivedfrom eroding till deposits (District 830). In coastalfresh marshes, mineral outcropping and softsedimentary rocks in the watershed contributeto soil development.

2. Soils: salt marsh develops its own soil of accu-mulated mud, roots and organic material fromthe decay and breakup of salt-marsh plants. Thehigh amount of organic debris in “salt marshpeat” leads to anaerobic, or oxygen-free, condi-tions around the roots. Spartina alterniflora, theprincipal low-marsh species, has air spaces inthe stem, which allow oxygen to reach down intothe sediment to supply the roots of the plant.2

Soils in coastal fresh marshes are generally allu-vial—fine material rich in organic materials andnutrients.

H2.5Tidal Marsh

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site, adding organic material to the soil. In estuar-ies, some of the production will be exported to lowerreaches or to the sea. Consumers on site includeinsects, waterfowl and small mammals.


The salt marsh is characteristically divided into highmarsh and low marsh, each with a distinct plantcommunity.

As a result of submergence, profiles of sedimentsin a salt marsh usually show layers correspondingto successive stages in marsh development. The low-est levels are freshwater peat, corresponding to theperiod when the area was above sea level, and suc-cessive levels follow the change to mud flat, lowmarsh and eventually high marsh (see FigureH2.5.14).

Low MarshCord Grass is the dominant plant, but occasionallyatypical algae, such as rockweed, can occur. Ondrier, bare patches, Glasswort, Sea-blite, SeasideSand Spurrey and Orach may be found.

Middle and High MarshMarsh Hay is the dominant plant; however, otherhalophytes, such as Sea-lavender, Arrow Grass, Sea-side Plantain, Milkwort, as well as various grasses,sedges and rushes, can also occur. The zone ofMarsh Hay is sometimes classed as “middle marsh”.4

In Atlantic Coastal marshes, the sedge Carexpaleacea is commonly the dominant high-marshspecies. In the Bay of Fundy, the high marsh is in-undated as frequently as once a month, in responseto tidal cycles and surges as the result of storms.

The coastal fresh marsh is between salt marshand freshwater fen. With rising sea level, freshwatermarshes will become more saline and eventually becolonized by halophytes. Along riverbanks, the mar-ginal estuarine species will give way to freshwaterspecies upstream. The drier edges will be colonizedby alder or willow.

SEASONAL CYCLE

In most of Nova Scotia, tidal marshes undergo adistinct seasonal cycle. Winter ice and wave actiondenude the lower exposed portions of the marsh,leaving a stubble field. The growth in spring forms abright-green lawn, which grows luxuriantly throughthe summer, but a second crop develops in sum-mer in some areas. No new leaves are produced

H2.5Tidal Marsh

A B

Figure H2.5.1:(A) Marsh map and (B) stratigraphy fromChezetcook Inlet. The freshwater sequence hasbeen radiocarbon-dated at 9600 years beforepresent, while salt marsh overlying it is dated at5000 years before present and represents a sealevel 11m lower than present. Modified afterWetlands of Canada. 4

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tion (e.g., Cord Grass) and succulent structures forwater retention (e.g., Glasswort).

Nova Scotia salt marshes are dominated by theCord Grass Spartina alterniflora in the low marshand Spartina patens at higher levels, but marshes inthe Bay of Fundy also include Seashore Salt-grassDistichlis spicata at higher levels. (Figure H2.5.2shows the distribution of Spartina spp. at differentlocations in the province.)

Eel Grass frequently occurs in the lower inter-tidal and subtidal zones adjacent to Nova Scotiasalt marshes, but is found infrequently in the Bay ofFundy (e.g., Five Islands Provincial Park [Unit 710]).In contrast to the salt-marsh vegetation, Eel Grassis found only below low-tide level.

Various marine fungi may be associated with andresult in the decomposition of Spartina.7

Pannes frequently contain Sea Lettuce,filamentous algae and aquatic angiosperms

H2.5Tidal Marsh

after early August.5 Fall frosts turn the marshes arusty brown. The scraping in winter and sloughingoff of leaves during the summer is key to the role oftidal marshes in marine communities, because thematerial becomes food for marine organisms.

Bay of Fundy low marshes have a limited growingseason—from May to October—and all vegetationdies in the fall. Frequent and energetic tidal flooding,coupled with the low marshes’ relatively exposed po-sition, results in a substantial removal of vegeta-tion through the year. Low marshes are also sub-ject to destructive action of sea ice every winter.6

PLANTS

Salt marsh PlantsPlant life in the salt marsh is salt-tolerant andincludes flowering plants (angiosperms), algae andmicroscopic fungi. Adaptations include salt excre-

Figure H2.5.2:Distribution ofSpartina spp. andother salt-tolerantspecies at differentlocations in theprovince.Percentages refer tosurface areacovered by eachspecies. Modifiedafter Wetlands ofCanada. 4

(More over page)

Distance along transect (m)

150

100

50

0

-50

Elevationabovesea level (cm)

Head of Chezzetcook Inlet, (unit 833)

Spartina alterniflora100%

Jincus gerardii (80%)Cyperaceae (15%)

Solidago sempervirens (<5%)

180 170 160 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 0

Distance along transect (m)

200

100

50

0-50

Elevationabovesea level (cm)

Mouth of Chezzetcook Inlet, (Unit 833)Spartina alterniflora100%

Cyperaceae (60-100%)

120 110 100 90 80 70 60 50 40 30 20 10 0

Spartina pectinata (100%)Spartina alterniflora (70%)Spartina patens (30%)

Spartina patens (70%)Spartina alterniflora (30%)

Spartina patens (100%)

150

Distance along transect

Elevationabove base ofSpartinaalterniflora (cm)

Spartina alterniflora(10-100%)

200

150

100

50

0

-500100200200300400

Spartina patens (90%)Spartina alterniflora (10%)

Distichilis sp (50%)Spartina patens (50%)

Spartina patens (100%),occasional

Spartina alterniflora

Spartina patens (50%),Spartina alterniflora (50%)

Kingsport Marsh, (District 610)

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(particularly Widgeon Grass). Pannes in low marshesmay contain Eel Grass; in high-marsh areas, theycontain Ditch-grass and Horned Pondweed.

Coastal Fresh-marsh PlantsThe plant life present in coastal fresh marshes willvary according to local conditions, but is dominatedby conspicuous grasses, rushes and sedges.

At the upper edges of the marsh, where the freshwater from the water table is near the surface, bul-rushes, cattails and sedges occur. Spartina pectinatais a common species. Reed Grass is common insome places in the Annapolis Basin, Minas Basin(District 610) and Chignecto Bay (Unit 533).

In sandy soil, the nutrient condition may be rela-tively poor, resulting in patches of vegetation simi-lar to that of bogs. Sphagnum spp., rushes and cran-berry, together with Sundew, Pitcher Plant, SeasideButtercup, Marsh Cinquefoil and Silverweed com-monly occur. This community is mainly foundwhere sand dunes intergrade with tidal marshes.

Bulrush marsh may be extensively developedaround shallow lakes, which also have abundantgrowths of pondweed (Potamogeton) and Ditch-grass, depending upon the salinity.

ANIMALS

Salt marshes are inhabited by a range of lower andhigher animals. Invertebrates include both marineforms living on the sediments and terrestrial arthro-pods, such as insects and spiders, that invade thestands of Spartina during the growing season. Themarine species are tolerant of a wide range of salinityand temperature, and of the high levels of suspendedsediment which are characteristic of the marsh. Spe-cies may include amphipods (Gammarus spp.) andisopods (Idotea spp.); various bivalve molluscs (theSoft-shell Clam, Fingernail Clam, the Blue Mussel andRibbed Mussel); and several gastropod species, includ-ing periwinkles, Spire Snail, and the Eastern Mud Snail.

In pannes, common species include the Spire

H2.5Tidal Marsh

Figure H2.5.2 (Continued): Distribution of Spartina spp. at different locations in the province. Modified after Wetlands of Canada. 4

Distance along transect (approximately 55 m)


Wallace Harbour, (sub-Unit 521a)

Mudflat

200

150

100

50

0

Spartina alterniflora (100%)

Spartina alterniflora (50%)Spartina patens (50%) Spartina patens (50%)

Potentilla sp.,Solidago sp., (50%)

Spartina pectinata,Juncus gerardii

-50

Spartina patens (99%)Atriplex (1%)

Juncus gardii (100%)

Distance along transect (approximately 100 m)


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Spartina alterniflora (100%)300

250

200

150

100

50

0

Spartina alterniflora (70%)Spartina patens (30%)



Cyperaceae (90%)Spartina patens (10%)

Cyperaceae(100%)

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SPECIAL FEATURES

• Pannes are shallow ponds which developinitially in poorly drained low-marsh areas, butwhich may persist for long periods of time. Oldpannes may be found in high-marsh areas.Pannes may also form in the high-marsh areasby destruction of marsh sod by ice action. Theextreme salinities and temperatures of pannesprevent colonization by surrounding grasses.

• Rising sea level: The character of salt marshesin Nova Scotia is linked to rising sea level.Around the edges of marshes, dead sprucetrees demonstrate the slow marine transgres-sion of the land (0.3 m per 100 years).

• Halophytic (salt-tolerant) plants: Angiospermscapable of excreting salt and storing water arethe characteristic plants of the tidal marshes.

• Elephant Grass (Common Reed): The smallbeds of Phragmites australis that occur incoastal fresh marshes around the Annapolisarea (District 610), Minas Basin (District 620and sub-Unit 913a) and Tantramar Marshes(Units 523, 913b) are notable because of the 2-to 3-m height of the full-grown plant. Thespecies occurs in many old dyked areas andmay have been introduced by the Acadians as athatching material.

• Ecological significance: Salt marshes areprobably the major source of food material forthe marine ecosystem in the Bay of Fundy andmake an important contribution to marinesystems in other areas.

• Migratory waterfowl: Tidal marshes, particu-larly coastal fresh marshes, are importantmigratory-waterfowl feeding areas in fall andearly winter. They are also important breedingareas for some species of ducks.

• Cultural associations: Traditional Mi’kmaqcustom and decorative work uses Sweet-grass,which occurs at the upper edge of many saltmarshes. Some of the salt-marsh plants areedible (Glasswort, Orach).

Salt marshes were used by early settlers, andare used to this day, as a rich source of hay. Anearly practice involved storing hay in stacks onplatforms (staddles) in the marsh. The promiseof the rich lands led early Acadian colonists tothe area to construct dyke systems for reclaim-ing the land. As a result, much of the original Bayof Fundy salt marsh has been converted to per-manent cropland (see T12.7).

H2.5Tidal Marsh

Snail and periwinkles. Bay of Fundy marshes andparts of the Atlantic coast have large populationsof the anemone Nematostella; the sea slug Elysiachlorotica, which has photosynthetic algae embed-ded in its skin, occurs occasionally.

Killifish, sticklebacks, silversides and eels are of-ten common in pannes, and many of these species,as well as juveniles of local fish species, includingflounder, can be found in waters of the salt marsh.

Salt marshes are important feeding, over-wintering and breeding habitats for waterfowl. Vari-ous species of ducks, herons, and shorebirds usethe marshes or rely indirectly on food organismsnourished by salt-marsh production. The Sharp-tailed Sparrow uses the salt marshes for breeding.

Coastal Fresh-marsh AnimalsThe aquatic fauna in coastal fresh marshes is gen-erally poor, being restricted to insects and theirlarvae—water boatmen (Corixidae), flies and mos-quitos and succineid snails. Freshwater molluscsand other invertebrates may be introduced by mi-gratory ducks and geese to more stable bodies ofwater. The bird and mammal life is important, par-ticularly waterfowl, Muskrat, raccoon, mink andsmall mammals. The Northern Harrier nests onthe ground in this habitat.

YTNUOC HGIHHSRAMTLAS

WOLHSRAMTLAS

silopannA 221 301

hsinogitnA 16 822

noterBepaC 69 891

retsehcloC 327 364

dnalrebmuC 7831 8901

ybgiD 862 083

hguorobsyuG 77 87

xafilaH 371 407

stnaH 298 296

ssenrevnI 811 842

sgniK 716 238

grubnenuL 111 841

uotciP 14 572

sneeuQ 441 811

dnomhciR 58 671

enrublehS 784 317

airotciV 19 861

htuomraY 0561 8051

Table H2.5.1: Distribution of salt marshes in Nova Scotia, by county(areas in hectares). From the Nova Scotia Department of Development,1984.

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Nova Scotia tidal marshes are part of a band of saltmarshes which extends from southern Labrador tothe Gulf of Mexico. Tidal marshes are found insheltered locations all around the coast of Nova Scotia(their distribution is shown in Table H2.5.1 and Fig-ure H2.5.3).8

The most extensive tidal marshes are the highand low marshes of the Inner Bay of Fundy, MinasBasin (District 610 and Unit 913) and Chignecto Bay(Units 533, 913). Large areas of these marshes, how-ever, have been converted to dykeland. In theAmherst area at the head of Cumberland Basin, theTantramar Marshes dominate the landscape (Unit523). Marshes along the Northumberland Strait andAtlantic Coast are often well developed (e.g.,Chezzetcook Inlet, Halifax County; and Chebogue,Yarmouth County [District 830]), but many small ar-eas in bays and estuaries are also found here. Thesemarshes are more productive than those of the Bayof Fundy. Marginal salt marsh vegetation occurs inthe Bras d’Or lakes (Unit 916) due to the negligibletidal range in the area.

Coastal fresh marshes are widely distributed insmall areas all around the province, especially inassociation with salt marshes. The best develop-ment occurs in the upper reaches of the Bay ofFundy, in Cobequid Bay (District 620 and sub-Unit913b) and Chignecto Bay (Unit 523).

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H2.5Tidal Marsh

Associated TopicsT4 Colonization, T7 The Coast, T10 Plants, T11.5Freshwater Wetland Birds and Waterfowl, T11.6Shorebirds and other Birds of Coastal Wetlands,T11.17 Marine Invertebrates, T12.7 The Coast andResources

Associated HabitatsH1 Offshore, H2 Coastal, H2.6 Dune System, H6.3Mixedwood Forest

References1 Scott, D.B. and F.S. Medioli (1980) Quantitative

Studies of Marsh Foraminiferal Distributions inNova Scotia: Implications for Sea Level Studies.Cushman Foundation for ForminiferalResearch. (Special Publication No. 17).

2 Hatcher, A., D.G. Patriquin, Y.F. Fern, A.J.Hanson and J. Reade eds. (1981), Salt Marshesin Nova Scotia: A Status Report of the Salt MarshWorking Group. Dalhousie University Institutefor Resource and Environmental Studies,Halifax.

3 Steever, Z.E., R.S. Warren and W.A. Niering(1976) “Tidal energy subsidy and standing cropproduction of Spartina alterniflora.” Estuar.Coast. Mar. Sci. 4.

4 National Wetlands Working Group (1988)Wetlands of Canada. Sustainable DevelopmentBranch, Environment Canada, Ottawa andPolyscience Publications Inc., Montreal.(Ecological Land Classification Series, No. 24).

5 Cranford, P.J., D.C. Gordon and C.M.Jarvis (1989) “Measurement ofcordgrass, Spartina alterniflora,production in a macrotidal estuary,Bay of Fundy.” Estuaries, 12.

6 Gordon, D.C., Jr., and C. Desplanque(1983) “Dynamics and environmentaleffects of ice in the CumberlandBasin of the Bay of Fundy.” Can. J.Fish. Aquat. Sci. 40.

7 Boland, G.J. and D.W. Grund (1979)“Fungi from the salt marshes ofMinas Basin, Nova Scotia.” Proc. N.S.Inst. Sci. 29.

Additional Reading• Erskine, J. (1958), “Along the dikes.” J.

Educ. (Halifax, N.S.).Figure H2.5.3:Location of tidalmarshes inNova Scotia.

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H2.6 DUNE SYSTEM

H2.6Dune System

Dune habitats are exposed shoreline systems of oneor more sand ridges derived from wind- and wave-transported material.

Plate H2.6.1: Dune system at Dominion Beach, Cape Breton County (Unit 531). Photo: R. Merrick

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Sandy Shore Colonizing Zone Yellow Dune GrasslandGrey Dune

Beach Grass • SeaRocket • Sandwort •Orach

Beach Grass •Poison Ivy, Carexsilicea

Poison Ivy • Beach Grass •Bayberry • False Solomon’ sSeal • Grasses • Lichens •Mosses

FORMATION

In Nova Scotia, this is a coastal habitat resultingfrom the deposition of sand on beaches in areaswith sufficient sediment supply. Sand is depositedon the upper levels of the beach by both wave andwind action and becomes stablized by the growthof American Beach Grass (Marram Grass). New duneridges are developed successively on the seawardside. The extent to which a coastal dune system willdevelop in Nova Scotia depends upon the sedimentsupply and the erosional/depositional environment,particularly the rate of sea-level rise.

PHYSICAL ASPECTS

1. Soil: wave- and wind-deposited sand is con-stantly shifting and has low nutrient levels.

2. Relief: topographically, the dunes are a succes-sion of parallel ridges (dunes) and depressions(slacks). Ridges become lower and wider withage, due to compaction and spreading.

3. Drainage: ridges are well drained, but the leach-ing of material from the sand results in the even-tual formation of hard pans and interrupteddrainage in the slacks.

4. Exposure: dunes are subject to a high degree ofexposure resulting from wind, blowing sand andsalt spray

ECOSYSTEM

This is a natural ecosystem with low species diver-sity in the early stages of succession. Primary pro-duction is low, due to low nutrient levels and expo-sure. Diversity of consumers increases during thecourse of succession. The initial grassland systemchanges to a forest system over time.

H2.6Dune System

Figure H2.6.1: A diagrammatic cross section of a prograding dune sytstem, showing the main features of succession. Based upon information fromPomquet Beach (sub-Unit 521b). Not drawn to scale. (Continued on next page).


On a prograding dune system, bare, loose sand ofthe beach is colonized and stabilized by AmericanBeach Grass. As the stable soil increases organic(humus) content and water-retaining capability, theBeach Grass community is replaced by an increas-ing variety of plant species, including heath plants,before giving way to coastal spruce, fir forest. Theseral stages are usually represented by dune ridgesof different ages, with distinct plant communities.The details and extent of the successional sequencewill depend upon local conditions. The destructionof the vegetation cover in the dune system can causedamage to the system by wind erosion (blowouts).Sand dunes often provide the shelter required forsalt-marsh development.

PLANTS

There are distinct plant communities associatedwith the seral stages of dune succession. These aresummarized on the diagram of the Pomquet dunesystem shown in Figure H2.6.1.

The most important species that dominates thepioneer-plant association is American Beach Grass.Colonization of new sand may be by seed or runnersfrom the established plants on the primary (“Yel-low”) dune ridge. The pioneer-plant association in-cludes typical beach plants: Sea-rocket, Sandwortand Orach.

The “Yellow dune” is also dominated by AmericanBeach Grass but the diversity of plant species is in-creased to include Poison Ivy and the sedge Carexsilicea. Beach Pea is another species of this community.

The “Grey dune” community, in which activedeposition of sand has ceased, continues the basicassociation of “Yellow dune”, but the Beach Grass

Blue Grass • Hair Grass •Tickle Grass • Poison Ivy •Lichens

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P A G E

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is beginning to give way to a variety of other plants,including grasses, Scouring Rush, Bayberry and li-chens. Lichens, particularly species of Cladonia, maybe the dominant vegetation in fairly extensivepatches.

The “Grassland” community shows the final re-placement of the Beach Grass by other grass spe-cies and the last stage before the “Heath and Scrub”ecotone that borders the White Spruce/fir, maple,birch forest association (H6.3). This communitycommonly includes Wild Rose and various heathplants, as well as individuals of the pioneer coni-fers.

In the depressions between beach ridges, knownas “slacks”, poor drainage and low nutrients sup-port a plant association of a “bog” character, withMyrica gale and Cranberry. In later stages of suc-cession, these may become alder swamp or pondhabitat.

ANIMALS

The development of fauna relates to the stage of suc-cession. Improved, stable soil and plant-species di-versity support more diversified fauna. The uppersand, beach community of amphipods (Talorchestia),tiger beetles, flies and spiders (see H2.3) extends intothe colonizing zone of the Beach Grass. At later seralstages, the diversity of insects increases and othergroups of soil organisms, such as snails and slugs,become established. Vertebrates include snakes,small mammals and birds (Savannah Sparrow [Ips-wich Sparrow on Sable Island] and Snow-buntingsin winter).

H2.6Dune System

SPECIAL FEATURES

• Pioneering role and adaptation of AmericanBeach Grass

• Classic features of sand-dune succession• Fragility of the system• Special case of Sable Island–Ipswich Sparrow• Dune-restoration programs in Nova Scotia

include using discarded Christmas trees tostabilize the mobile sand prior to the BeachGrass establishment.


Sand-dune systems occur in exposed coastal areaswhere there is adequate sediment supply. TheNorthumberland Strait (District 520), Cape Breton(Districts 530 and 550), and the Atlantic Coast (Dis-tricts 830, 840 and 890) have the best examples.Pomquet Beach, Antigonish County, is the best pro-vincial example of a prograding dune system. Man-agement of sand dunes is an essential part of rec-reation-beach development. There are only a fewsand dunes in the Bay of Fundy (for example, Ap-ple River [Unit 532]).

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Associated TopicsT7.1 Modifying Forces, T7.3 Coastal Landforms,T10.2 Successional Trends in Vegetation, T10.5Seed-bearing Plants, T10.11 Lichens, T12.7 TheCoast and Resources

Associated HabitatsH2.3 Sandy Shore, H2.5 Tidal Marsh, H6.3Mixedwood Forest

Cattail • Bulrush• Aspen

White Pine • WhiteSpruce • Red Oak •Maple

AlderWhite Spruce • RedOak • Swamp Maple •Striped Maple • SugarMaple • Aspen

Sweet Gale• Cranberry

Crowberry • Foxberry •Blueberry • Bearberry •Juniper • Wild Rose •Bayberry • Aspen • Red Oak •Hawthorn • Birch • Wild Pea •Gooseberry • BastardToadflax • Lichens

Bog Forest Forest SlackSwampHeath and Scrub Forest

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P A G E

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Additional Reading• Hales, W. (1992) Sand Dunes of Nova Scotia.

M.Sc. thesis, McMaster University, Hamilton,Ont.

• Institute for Environmental Studies (c. 1976)Maintenance of Beaches: Technical Report.Dalhousie University, Halifax.

• Taylor, R.B. and D. Frobel (1990) “Approachesand results of a coastal dune restoration pro-gram on Sable Island, Nova Scotia.”Proceedings Canadian Symposium on CoastalSand Dunes 1990. Atlantic Geoscience Centre,Geological Survey of Canada, Dartmouth.

Plate H2.6.2: Freshwater Cattail marsh in a slack between wooded dune ridges inland from Pomquet Beach, Antigonish County (sub-Unit 521b).The photograph corresponds to the cross section at the far right of Figure H2.6.1. Photo: D. Davis

H2.6Dune System

Documents

H2.1 ROCKY SHORE - Dalhousie University