Aquatic habitats

Aquatic habitats

Freshwater environments warmwater cool water cold water LOTIC benthic darters, dace, sculpin, darters sculpin stonerollers, bullhead water bluegill, esocids yellow perch trout, salmon column smallmouth bass, fallfish, channel cats LENTIC benthic dace sculpin, darters burbot, sculpin demersal bass, centrarchids yellow perch pelagic walleye clupeids 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

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 1m)

Depth (m) (euphotic) (disphotic) (aphotic)

saline, cold closed ~ 3.7 mya hot saline, cold

2.5°C 14°C 23°C 2.5°C

180 MYA 225 MYA 130 MYA 70 MYA

Barriers to marine dispersal continental drift – separated continental shelf areas continents – absolute barriers isthmus of Panama, Suez, closed ~ 3.7mya submerged geographic features – mountains, sills temperature – tropics vs. temperate, currents salinity barriers – polar regions

Freshwater fishes Paleozoic MYA Cambrian 570 Ordovician 505 first fishes Silurian 38 Devonian 408 placoderms; age of fishes Carboniferous 360 hagfishes and lampreys Permian 286 Mesozoic Triassic 245 Pangea convergence – paddlefish, sturgeon Jurassic 208 Pangea split bowfins, gars, lungishes Cretaceous 144 Esocidae, Umbridae, Salmonidae Cenozoic Tertiary Paleocene 65 Cyrpinidae, Percidae, Catasomidae Eocene 58 Centrarchidae, Ictaluridae, Oligocene 38 Miocene 24 Pliocene 5 Quaternary Pleistocene 1.8 period of glaciation Recent

Freshwater fishes 180 MYA 225 MYA 130 MYA 70 MYA

Holarctic no FW fishes 250 1500-3000 950spp 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

Aquatic habitats