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European Starling Essay writing Title of essay Please write a short paragraph why you write about the chosen topic. 5 citations (no annotation, yet) The European starling was first introduced to the United States in New York City, in 1890. Inspired by William Due date: in the week after Shakespeare's plays, Eugene Scheffland let loose one springbreak hundred starlings in Central Park. How invasives move/spread Cane toads in Australia Cane toads were deliberately introduced to Australia from Hawaii in 1935 in an attempt to stop French’s Stow-aways Cane Beetle and the Greyback Cane Commerce/Curiosity Beetle from destroying sugar cane crops in North Queensland. The Recreation Australian Bureau of Sugar Aesthetics Experimental Stations made the release of 101 cane toads at Biological control Gordonvale in Queensland in 1935. They were unsuccessful in controlling the cane beetles. Biological control = Introduction of predators to control a prey species Cane toads in Australia How do invasives move/spread Invasion and the evolution of speed in toads Benjamin L. Phillips 1 , Gregory P. Brown 1 , Jonathan K. Webb 1 and Richard Pattern of a “typical” invasion Shine 1 Cane Toads - Latent phase (small population size) An Unnatural Cane toads seem to have honed their dispersal ability to History devastating effect over the generations. (1987) Rapid population growth and spread Cane toads ( Bufo marinus ) are large anurans (weighing up to 2 kg) that were introduced to Australia 70 years ago to control insect pests in sugar-cane fields. But the result has been disastrous because the toads are toxic and highly invasive. Here we show that the annual rate of progress of the toad invasion front has increased about fivefold since the toads first arrived; we find that toads with longer legs can not only move faster and are the first to arrive in new areas, but also that those at the front have longer legs than toads in older (long-established) populations. The disaster looks set to turn into an ecological nightmare because of the negative effects invasive species can have on native ecosystems 1, 2 ; over many generations, rates of invasion will be accelerated owing to rapid adaptive change in the invader 3 , with continual 'spatial selection' at the expanding front favouring traits that increase the toads' dispersal 4, 5 .

Opuntia Effect of invasive species in South-Africa Predation Reconstructing 50 years of Opuntia stricta invasion in the Kruger National Park, South Africa: environmental determinants and propagule pressure Llewellyn C. Foxcroft, Mathieu Rouget, David M. Richardson and Sandra Mac Fadyen Diversity and Distributions, (2004) 10: 427–437 Introduction The brown tree snake Brown tree snake was first detected on ( Boiga irregularis ) Guam in the 1950s near on Guam the Naval Port (central Guam), but may not have become conspicuous away from the port area until the early 1960s. � By the mid 1960s, the snake had colonized over half of the island. � In 1968, the snake had reached the extreme northern end of the island and was present throughout the island, although its densities varied widely from region to region. Status of forest species on Guam Threat to other species

Eradication and Detection Other threats Effect of invasive species Predation Competition (native vs House geckos in the Pacific) http://www.fort.usgs.gov/Resources/Education/BTS/ Effect of invasive species Effect of invasive species Myrica faya on Hawaii Predation Predation Competition Competition Hybridization Hybridization Environmental engineering West slope cutthroat trout Dr. Donald E. Gardner, University of Hawaii, http://www.botany.hawaii.edu/faculty/gardner/biocontrol/myrica%20faya/myrica.htm

Habitat invaded by Myrica faya Effect of invasive species Myrica faya on Hawaii Predation Competition Hybridization Environmental engineering N-fixing root nodules Dr. Donald E. Gardner, University of Hawaii, Dr. Donald E. Gardner, University of Hawaii, http://www.botany.hawaii.edu/faculty/gardner/biocontrol/myrica%20faya/myrica.htm http://www.botany.hawaii.edu/faculty/gardner/biocontrol/myrica%20faya/myrica.htm Effects of invasive species Factors affecting invasion Predation Competition Basics Hybridization Factors affecting invasion Introduction history Environmental engineering Economic effects Invasive species is one of the major environmental issues of this century. The economic cost to the US of invasive species is at least $137B/year. (ESA 2000) Each year, ~ $23 billion nationwide is lost to the effects of invasive plants on agriculture, industry, recreation, and the environment. An estimated 1860 hectares (4600 acres) of land are invaded daily by invasive plants. (Federal Highway Administration 2000) Factors affecting invasion: Time since introduction Introduction history Correlation of area and introduction date Pathways of introduction Ballast water Propagule pressure counteract small population challenges (e.g. genetic effects) Opuntia invasion in South-Africa Time since introduction Demographic processes Adaptation

Factors affecting invasion: Factors affecting invasion species characteristics High dispersal rate Basics Persistence at low density and fast growth Factors affecting invasion � e.g. asexual reproduction Introduction history Species characteristics Good ecological match large native range (can adapt to different habitats) generalists Associate with humans An example of a predictive trait from Characteristics of invasive species the dayflower family • Australian Weed Risk Assessment Model: Predict what introduced species are likely to become invasive based on species traits. Jean Burns Is self-compatibility associated with Self-compatibility is associated with invasiveness? invasiveness. Self-compatible Invasive Murdannia nudiflora Murdannia simplex Self-incompatible Noninvasive invasive noninvasive Pollen grain Self-incompatible Self-compatible Pagel94: D = 3.60, P = 0.01

Self-compatibility is associated with Factors affecting invasion: community invasiveness. characteristics Self-compatible Invasive Self-incompatible Noninvasive Basics Predicting invasions Introduction history Species characteristics Characteristics of invasible ecosystems Pagel94: D = 3.60, P = 0.01 Characteristics of invasible ecosystems Disturbed/Early in succession good “Ecological Match” Characteristics of invasible Invasible ecosystems: Enemy ecosystems Release Hypothesis Native Range Introduced Range Disturbed/Early in succession good “Ecological Match” herbivory herbivory Predators few or absent (=enemy release hypothesis) plant abundance plant abundance

Invasible ecosystems: low Characteristics of invasible diversity? ecosystems Islands are more invasible than mainlands (Elton 1958) Disturbed/Early in succession Low diversity local communities are less invasible (Levine good “Ecological Match” 2000) Predators few or absent (=enemy release hypothesis) High diversity habitats are more invaded at large scales (Stohlgren et al. 2003) Low diversity? Observations from islands, small-scale experiments, and mathematical models have generally supported the paradigm that habitats of low plant diversity are more vulnerable to plant invasions than areas of high plant diversity. We summarize two independent data sets to show exactly the opposite pattern at multiple spatial scales. More significant, and alarming, is that hotspots of native plant diversity have been far more heavily invaded than areas of low plant diversity in most parts of the United States when considered at larger spatial scales. Our findings suggest that we cannot expect such hotspots to repel invasions, and that the threat of invasion is significant and predictably greatest in these areas. Invasible ecosystems: low Invasive species diversity? Basics Predicting invasions Introduction history Characteristics of invasive species Characteristics of invasible ecosystems Managing Invasives What to do about invasives? Invasives: reduce human impact Prevent entry reduce human impact

What to do about invasives? What to do about invasives? Biological Control Prevent entry reduce human impact public education Host Specificity border control (Australian Weed Risk Assessment) Agent effectiveness Removal of invasives by hand vs pesticides biological control Biological Control: host specificity Biological Control: host specificity (Soberón 2002) (Soberón 2002) Biological Control: host specificity Biological Control: agent effectiveness Opuntia spinosissima Opuntia triacantha Rare in native habitat lower chance of resistance in host Environment matching Using demographic models of evaluate effectiveness (remember PVAs?)

Biological Control: agent effectiveness • Scotch broom Ingrid Parker 2000, PVA 99.9% of seeds in prairies and 70% of seeds in urban populations need to be destroyed to stop invasion of scotch broom Biological Control: agent effectiveness Characteristics of invasible ecosystems PVA: Elasticity analysis of how to stop Scotch broom Invasion front (fastest growing population) Established population (slowest growing population Disturbed/Early in succession good “Ecological Match” Predators few or absent (=enemy release hypothesis) Low or High diversity? Fragmentation