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Higher Plants within Aquatic Ecosystems. ENV 311/EEB 320 Winter 2006. Bryophyta (mosses & liverworts). Sphagnum sp. (sphagnum mosses) feathery foliage, often growing in dense mats that readily absorb water acid indicator: bogs, acid wetlands
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Higher Plants within Aquatic Ecosystems ENV 311/EEB 320 Winter 2006
Bryophyta (mosses & liverworts) • Sphagnum sp. (sphagnum mosses) • feathery foliage, often growing in dense mats that readily absorb water • acid indicator: bogs, acid wetlands • responsible for bog formation, foliage grows on itself forming bog mats
Phylum BryophytaFamily Sphagnaceae • Sphagnum spp.
Tracheophyta (vascular plants) • General information on aquatic vascular plants • food and habitat for aquatic animals • reduced support structure as adaptation to battering potential of water movement (i.e. dissected leaves, ribbon form, thin) • rigid stem structure not necessary in water • tendency to reduce roots or lack roots and have leaves that anchor plants and serve as roots • indicators of environmental quality and of ecosystem
Submergent, Floating, & Emergent • Submergent • spend entire life cycle (expect flowering) beneath surface of water • anchored to substrate • vegetative part of plant does not reach surface or terminal end lies horizontally just beneath surface • many species have flowers borne above water • watercress [Rorippa] • milfoil [Myriophyllum] • pondweed [Potamogeton]
Submergent, Floating & Emergent • Floating • Attached: leaves float on water’s surface but roots anchored in substrate • water lilies [Nymphaceae] • Unattached: float with most of plant body above surface; roots, if present hang free; move with winds and currents; can be problem weeds • duckweed [Lemna]
Submergent, Floating, & Emergent • Emergent • roots and basal portion grow beneath surface of shallow water • leaves and stems borne primarily in the air • cattail [Typha] • leatherleaf [Chamaedaphne] • arum [Araceae]
Terrestrial • Woody plants • Heavily fortified stems and branches • Leaves with a lot of structure • Broadleaf • Needle • Scales • Various methods of reproduction • Spores • Cones • Flowers
Birds and Mammals in Aquatic Ecosystems ENV 311/ EEB 320 Winter 2006
Why Birds? • Important predators of invertebrates, fish, mammals, reptiles and amphibians in aquatic ecosystems • Major vectors for transport of plants and wingless invertebrates • Interesting and ubiquitous members of aquatic communities • Along with fish, enjoy fairly broad support from the public • Good way to generate interest in habitat preservation/restoration
Family GaviidaeGavia • Loons • Habitat: mainly northern lakes • Notes: • Divers: feed mainly on fish • Very distinctive vocalizations • Alarm call • Short hoot • 1 breeding sp. in MI: common loon (Gavia immer) University of Michigan Animal Diversity Web
Family Ardeidae • Bitterns, Herons, and Egrets • Habitat: Open wetlands, lakeshores, rivers • Notes: • Often seen stalking prey: feed mainly on fish, also amphibians and invertebrates • Egrets/herons often build nests in shrubs/trees and may be colonial breeders • Bitterns prefer dense emergent vegetation and tend to be solitary University of Michigan Animal Diversity Web
Family ArdeidaeBitterns • 2 spp. in Michigan • American bittern: • Call distinctive—like a piledriver in a puddle? • Secretive, often strikes vertical pose to blend in with vegetation
Family ArdeidaeHerons and Egrets • 6 spp regularly found in MI • Less secretive and more easily spotted than bitterns • Egrets are white, herons may be various colors University of Michigan Animal Diversity Web
Family Accipitridae University of Michigan Animal Diversity Web • Hawks and eagles • 2 spp. that are most often found in MI aquatic ecosystems are: • Bald eagle (above) • Northern harrier (below) • Bald eagle found along rivers/wetlands, often preys on fish • Making strong recovery from very low numbers for last half of 20th century • Northern harrier often hovers over open wetlands, preys on small mammals, amphibians and other birds
Family PandionidaePandion haliaetus University of Michigan Animal Diversity Web • Osprey (1 sp.) • Habitat: Mainly rivers and wooded edges of lakes • Notes: • Build enormous nests of sticks high off the ground, 3-5 ft in diameter • Feed mainly on fish but cannot swim—have been known to drown if they hook into too large a fish • As with many raptors, numbers have risen since elimination of DDT from the food web
Family Laridae • Gulls and terns • Ring-billed gull Common tern • Gulls tend to be thicker-billed and stouter; frequently walk • Facultative predator/scavenger • Terns are sleeker, designed for capturing fast prey • More predatory on small fish and invertebrates • May build nests on rocky shores, islands or floating mats of vegetation University of Michigan Animal Diversity Web
Family Anatidae • Ducks, geese and swans • Very diverse aquatic family • Habitats vary, from wooded wetlands and rivers (wood duck) to open water (greater scaup) • Notes: • Many feed by dabbling, i.e., sifting through mud for nutritious invertebrates, seeds, shoots, etc. • Others are active predators of fish (e.g. mergansers) • Many valued by hunters—benefit (?) from conservation efforts • Webbed feet for swimming University of Michigan Animal Diversity Web
Family AnatidaeDucks • Short-necked, often with colored primary feathers • Most species migratory • Most have sexually dimorphic coloration • Mallard (Anas platyrhyncos) very common and spreading in NA • Am. black duck (Anas rubipres) very closely related to mallard and disappearing due to interbreeding
Family AnatidaeGeese and Swans • Longer-necked and usually larger than ducks • Mainly migratory--most prefer more northerly breeding ranges than ducks • Canada goose (Branta canadensis) is very common near water/grass in MI
Family GruidaeGrus canadensis • Sandhill crane • Habitat: migratory; wetlands critical for breeding success; past population declines mirrored wetland loss • Notes: • Omnivorous, but notorious for eating waterfowl eggs during breeding season • Elaborate mating dance • Social, gregarious bird
Family AlcedinidaeCeryle alcyon • Belted kingfisher • Habitat: waterways and lakes with available perches and abundant food • Notes: • Nest in 1-2 meter long tunnels, often in riverbanks • Voracious predator of small fish • Call is rattling
Family Charadriidae • Sandpipers and phalaropes • Habitat: shores of lakes, wetlands, large rivers • Notes: • Speciose group (18 spp. commonly migrate through or reside in MI) • Size ranges from sparrow-sized to length of a small hawk • Many have very long legs/bills for wading and deep probing of the substrate for invertebrates
Mammals • Although most mammals will periodically visit aquatic ecosystems, only a few species are strongly associated with water in MI • Some are voracious predators of fish and mollusks • Others may construct large structures and significantly alter hydraulics of flowing waters • All have physiological adaptations, such as webbed feet and waterproof fur that allow them to thrive in aquatic ecosystems
Castor canadensis • American beaver • Notes: • Noted for its ability to construct wood/earth dams, altering flow to suit its needs • Uses large, gnawing teeth to fell trees • Consumes nutritious bark/buds • Uses wood for dam- building • Characterized by large size (may reach 35 kg) waterproof coat and large, paddle-like tail • Trapped to near dangerous levels in 19th century; now common in most of NA
Lutra canadensis • River otter • Notes: • Intelligent and very adaptable predator—one of the few natural predators of snapping turtles • Prefers deep, relatively isolated rivers with healthy fish populations • Highly adapted for speed in water: sleek, with fully webbed feet
Mustela vison • Mink • Notes: • Well-adapted for hunting on land and in water—can swim well and run fast • Feeds on small mammals, fish, amphibians, birds • As with other aquatic animals, may take up residence in old muskrat or beaver lodges
Ondatra zibethicus • Muskrat • Notes: • Looks most like a small beaver, but can be distinguished by its thick rat-like tail • Builds easily recognizable lodges in shallow wetlands • Mainly herbivorous but will take crustaceans and mollusks as well