Outline. Quiz Assignment: Peer review due after Spring Break Lecture: Invasive species and communities Break Second half of WI Fishes (ID’s). Invasive species and communities. A prelim exam question….
Assignment: Peer review due after Spring Break
Lecture: Invasive species and communities
Second half of WI Fishes (ID’s)
“Are invasive species more likely to have large impacts on native communities via predation or via competition?”
Competition is important...just not as important as predation
5 Basic types of species interactions
Competition ...common use of a limited resource
What can be limiting....?
TimeHow do we see it or measure it?
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.
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.
Apparent competition - occurs indirectly between two species which are both preyed upon by the same predator.
Resource GradientCompetition's role in ecology and evolution
Evolution to minimize competition
Difficult (or impossible) to prove
Warmer Temps Cooler Temps
Lake Tanganyika Temps
M.J. Vander Zanden. 2005. The Success of Animal Invaders, PNAS 102: 7055-7056
-Leading cause of global biodiversity loss
-Particularly severe in freshwater ecosystems
- Contributing factor in 68% of fish extinctions in US and Mexico
- Cost $137 billion/year in US alone
- Numbers are increasing
Pelagic planktivores - Alewife, Rainbow smelt, white perch, bythotrephes
Benthic omnivores - round goby, rusty crayfish, common carp
Pelagic piscivores – Pacific salmon, brown trout, rainbow trout
Pelagic/benthic parasite – Sea lamprey
Stream insectivores – brown trout, rainbow trout
Pelagic filter-feeders – silver carp, bighead carp
Benthic filter-feeders – zebra mussel, quagga mussel
Establishment and Integration
Adapted From Vander Zanden et al. 2004
Mercado-Silva, N., J.D. Olden, J.T. Maxted, T.R. Hrabik, M.J. Vander Zanden. 2006. Forecasting the spread of invasive rainbow smelt in the Laurentian Great Lakes region of North America. Conservation Biology 20: 1740-1749.
More predictions… Fishes
42% (1,369 km) identified as suitable
(7% of state)
44% (8,878 km) identified as suitable
Kornis, M.S., and Vander Zanden, M.J. 2010. Forecasting the distribution of the invasive round goby (Neogobisu melanostomus) in Wisconsin tributaries to Lake Michigan. Can. J. Fish. Aquat. Sci. 67: 553-562.