1 ? 2 5 Basic types of species interactions XXXXXXXXXX Competition is important...just not as important as predation 2 1 ?

limited food habitat Competition ...common use of a limited resource What can be limiting....? food habitat

food habitat 2 dimension, but there are more.... FUNDAMENTAL REALIZED

Between and within species?? Intraspecific competition Interspecific competition

How do we see it or measure it? Population Abundance Time Individual Responses Behavior – feeding rate Physiology – growth rate Morphological – body size Population responses Abundance Distribution

3 types of competition?? Interference competition Exploitation competition Apparent competition

Interference competition - occurs directly between individuals via aggression etc. when the individuals interfere with foraging, survival, reproduction of others, or by directly preventing their physical establishment in a portion of the habitat. (-) A B (-)

Exploitation competition - occurs indirectly through a common, limiting resource, which acts as an intermediate. Ex. depletes the amount of food or fill up all the available space. (-) A B (-) + + - - R

Apparent competition - occurs indirectly between two species which are both preyed upon by the same predator. B A A B - - - - + + + P P

http://video.google.com/videoplay?docid=-6431936272692514162

Competition's role in ecology and evolution Resource partitioning Population Abundance Resource Gradient "species packing" Population Abundance Resource Gradient

Lake Malawi Lake Tanganyika Cichlids exhibit remarkable evolutionary convergence. Similar ecomorphs have evolved repeatedly within different cichlid assemblages. All of the cichlids in the left-hand column are from Lake Tanganyika. All of the cichlids in the right-hand column are from Lake Malawi, and are more closely related to one another than to any species within Lake Tanganyika. Note the similarities among color patterns and trophic morphologies.

Utilize resources along a gradient (See Wooton) Food particle size Temperature Habitat

Examples: Classic Werner and Hall Experiments Bluegill Green Sunfish Pumpkinseed

Examples: Ciscoes adaptive radiation (Lindsey 1981)

Modeling Competition Lotka-volterra model Competition coefficients The equations What the hell is an isocline, anyway? 4 graphs. See Molles Population Abundance Time

Exotics species that affect the ecology of native Wisconsin Fishes Pelagic planktivores - Alewife, Rainbow smelt, white perch Benthic insectivores – round goby, common carp Pelagic piscivores – Pacific salmon, brown trout Pelagic/benthic parasite – Sea lamprey Stream insectivores – brown trout, rainbow trout Pelagic filter-feeders – silver carp, bighead carp

Exotics fish utilize different habitats And a variety of food sources

How do they get here? People Ships ballast water Canals Aquaculture

Aquaculture Silver carp Bighead carp Ballast water Alewife white perch Round goby Intentional Stocking Pacific Salmon Brown trout Rainbow trout Common carp Rainbow smelt Canals Sea lamprey Rainbow smelt

LAKE SUPERIOR Species Earliest Record Unintentional or Intentional Transport or Release Mechanism(s) Alewife <1953 Unintentional Canals American eel 1970 Atlantic salmon 1972 Intentional Stocked Brown trout 1883 Brook silverside 2002 Unknown Chinook salmon 1967 Coho salmon 1966 Common carp 1897 Eurasian ruffe 1986 Ballast Water European flounder 1981 Fourspine stickleback Ballast Water or Live Bait Freshwater drum ? Stocked (assumed) Gizzard shad Live Bait or Aquaria Goldfish 1975 Kokanee salmon Pink salmon 1956 Intentional (unplanned) Rainbow smelt 1930 Rainbow trout 1895 Round Goby 1995 Sea lamprey 1938 Splake Threespine stickleback 1987 Tubenose goby 2000 White Perch LAKE SUPERIOR

3 aspects that make them so successful...? High fecundity – lots of eggs / individual Excellent competitors – better at gaining resources then native species Exploit a less well used resource

Detrimental to sport fisheries... round gobies to smallmouth bass nests http://people.cornell.edu/pages/gbs27/gbssmb.html

Detrimental to ....life as we know it on all lakes and rivers http://www.youtube.com/watch?v=2ChwJiKKBdA