• The exotic invasive candle bush Senna alata (L.) Roxb. in Baja California Peninsula, México, a new threat for relictual oasis

      Navarro, José; Rodríguez-Estrella, Ricardo; Univ Arizona, Sch Nat Resources & Environm (REGIONAL EURO-ASIAN BIOLOGICAL INVASIONS CENTRE-REABIC, 2019-12-11)
      We recorded the invasive candle bush (Senna alata) for the first time in oases of southern Baja California peninsula in October 2013 and February 2015. Candle bush is likely an escape from residential plantings in this region. Data on density, plant cover, number of pods per plant, and seeds per pod are presented. In the oasis of Santiago, candle bush plant density was low and contained mainly mature plants, which made up 90% of the total population. In the oasis of San Jose del Cabo, population density was higher, but individuals were mostly shorter than 10 centimeters in height, and 60% of the population consisted of seedlings and young plants. Mature plants were seen mainly in full bloom and early fruiting stages. Candle Bush is invading very dry climates in oasis systems, this is the first documented record of the species invading this kind of wetlands and even starting to invade tropical deciduous forest around arroyos. The introduction pathways and time since the introduction of candle bush into the peninsula are unknown, but no records existed before 2013 when we found the population. We strongly recommend eradicating this invasive species from Baja California oases now, while it is in the early stages of invasion.
    • Public risk perceptions associated with Asian carp introduction and corresponding response actions

      Kahler, Jessica; Liu, Rain; Newcomb, Tammy; Herbst, Seth; Gore, Meredith; Univ Arizona, Dept Commun (REGIONAL EURO-ASIAN BIOLOGICAL INVASIONS CENTRE-REABIC, 2020)
      Biological invasion pathways are strongly influenced by human behavior. This research aimed to build new understanding about public perceptions and expectations for possible management responses that might be used after detection of Asian carp in the Laurentian Great Lakes. Although the species are as yet unestablished, our research worked to inform communication that could be publicly responsive in the event of an invasion. Our objectives were to: 1) determine public risk perceptions associated with Asian carp; 2) determine public risk perceptions associated with different types of management responses to an Asian carp invasion; and 3) identify types of risk-related information and communication that would influence community support for different types of eradication or control approaches. Objectives were achieved by using a two-phase approach. Phase one utilized an online, voluntary, self-administered survey with 2788 responses received from a convenience sample of Laurentian Great Lakes Basin residents. Phase two included three "Thinkshops" of fishing and boating stakeholders in southern Michigan. Across all hypothetical Asian carp invasion scenarios, the application of rotenone to a large area was the most frequently selected management response. When impacts from Asian carp and their management were discussed, study participants supported framing risks in terms of environment and economy. Insights herein provide new evidence that can help narrow the gap between how invasion risks are perceived and responded to by natural resource managers to reduce social conflicts over, and potentially address, invasive species threats more rapidly.