Aquatic habitats Freshwater environments warmwater cool water cold
Aquatic habitats
Freshwater environments warmwater cool water cold water darters, dace, stonerollers, bullhead sculpin, darters sculpin bluegill, esocids smallmouth bass, fallfish, channel cats yellow perch trout, salmon dace sculpin, darters burbot, sculpin demersal bass, centrarchids yellow perch pelagic walleye clupeids LOTIC benthic water column LENTIC benthic salmonids, coregonids, lamprey
Estuarine environments
Estuarine environment - challenging 1. Freshwater; usually temporary residents 2. Diadromous a. Found in large numbers as they travel through estuary b. Staging area (before moving upstream) e. g. salmon c. Nursery (e. g. shad) 3. True residents (entire life cycle in estuary) Few species in this category, e. g. white perch 4. Non-dependent marine Commonly found in lower reaches of estuary e. g. sculpins, flounders, surfperch 5. Dependent marine (a least 1 life-cycle stage) Spawning grounds or nurseries or feeding grounds for adults
Intertidal environment – very harsh Crashing surf Strong currents/tides Daily exposure to air But, great spatial heterogeneity, abundance of food
Intertidal (littoral) environment Residential status of the ichthyofauna: 1. True residents: (dominant) e. g. sculpins, blennies, clingfishes, gobies, gunnels 2. Partial residents (juveniles): (dominant) e. g. blennies, surfperches, labrids, some cottids, pholids 3. Tidal (= feeders) many species 4. Seasonal (= spawners) few species
Neritic zone (to ~200 m)
Neritic zone terratogenic sources of nutrients within the photic zone, highly productive energy from waves, tides, for mixing coral reefs, kelp forests highly complex physical habitat, diverse physical niches highly speciose - about 40% of fish fauna - 6000 -8000 spp many species, few members, mostly small many specialized adaptations, particularly for feeding continental shelf area out to 200 m deep - average 700 km wide mud/silt substrate, not complex, little structural complexity mostly ground feeders - gadids, pleuronectids few species, very abundant, mostly large (up to 1 m)
Depth (m) (euphotic) (disphotic) (aphotic)
saline, cold closed ~ 3. 7 mya hot saline, cold
2. 5°C 14°C 23°C 2. 5°C
225 MYA 130 MYA 180 MYA 70 MYA
Barriers to marine dispersal continental drift – separated continental shelf areas continents – absolute barriers isthmus of Panama, Suez, closed ~ 3. 7 mya submerged geographic features – mountains, sills temperature – tropics vs. temperate, currents salinity barriers – polar regions
Freshwater fishes Paleozoic Cambrian Ordovician Silurian Devonian Carboniferous Permian MYA 570 505 38 408 360 286 Triassic Jurassic Cretaceous 245 208 144 Pangea convergence – paddlefish, sturgeon Pangea split bowfins, gars, lungishes Esocidae, Umbridae, Salmonidae 65 58 38 24 5 Cyrpinidae, Percidae, Catasomidae Centrarchidae, Ictaluridae, first fishes placoderms; age of fishes hagfishes and lampreys Mesozoic Cenozoic Tertiary Paleocene Eocene Oligocene Miocene Pliocene Quaternary Pleistocene Recent 1. 8 period of glaciation
Freshwater fishes 225 MYA 130 MYA 180 MYA 70 MYA
Holarctic no FW fishes 250 1500 -3000 950 spp Ethiopian 1800 2200 230
Native ichthyofauna: Atlantic salmon European eel Sea lamprey Brown trout Sturgeon Shad
Six ichthyofaunal groups based on origin (Gilbert, 1976): Eurasian Esocidae, Umbridae, Cyprinidae, Catostomidae, Percidae North American (endemics) Ictaluridae, Centrarchidae, Goodeidae, Amblyopsidae, Hiodontidae, Percopsidae, Aphredoderidae Marine origin Cottidae, Sciaenidae, Atherinidae, Cyprinodontidae, Petromyzontidae, Anguillidae Central American Poeciliidae South American Characidae, Pimelodidae, Cichlidae Archaic Old-World (Laurasian) Amiidae, Lepisosteidae, Polyodontidae, Acipenseridae
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